Independently tested ranking
Best A/B Testing Tools in 2026
We compared 10 of the best A/B testing tools on test types, statistics, ease of use, privacy and pricing, from free open-source options to enterprise platforms.
- Tools compared
- 10
- With a free plan
- 5 of 10
- Median entry price
- $24/mo
- Average rating
- 4.5
On this page
Which A/B testing tool is best?
The best A/B testing tools in 2026 are Optimizely for enterprise web and feature experimentation, AB Tasty for ecommerce testing and personalization, Convert for privacy-focused teams and CRO agencies, VWO for pairing tests with heatmaps and recordings, and GrowthBook for a free, open-source option. GrowthBook, PostHog and Statsig all have free plans, GrowthBook Pro costs $20 per user a month, and Unbounce includes A/B testing from $149 a month.
Our top picks
Best overall
Optimizely
Covers marketing page tests and engineering feature tests in one platform, with a trusted sequential stats engine built for large programs.
Paid plans from Custom (annual)
See why we picked itBest for ecommerce and personalization
AB Tasty
A friendly visual editor, ready-made widgets and personalization let ecommerce marketers test and roll out winners without developers.
Paid plans from Custom (annual)
See why we picked itBest free A/B testing tool
GrowthBook
Open source, free to self-host or start in the cloud, and analyzes tests on your own warehouse data.
Paid plans from $20/user/mo
See why we picked itKey takeaways
- Optimizely, AB Tasty and Kameleoon lead for enterprise programs, but none publish prices or offer a free plan. If budget rules them out, Convert and GrowthBook are practical Optimizely alternatives.
- GrowthBook, PostHog and Statsig have free plans, making them the best free A/B testing tools for startups and product teams with developers.
- Marketers who want a visual editor should look at AB Tasty, Convert or Optimizely; developer tools like Statsig and LaunchDarkly have no page editor.
- Client-side tests can flicker. Convert and Kameleoon are built for flicker-free delivery, which protects both user experience and your results.
- Traffic matters more than the tool. Low-traffic sites rarely reach significance, so test big changes, or use Unbounce Smart Traffic on landing pages.
What is an A/B testing tool?
The best A/B testing tools are split testing tools that divide your visitors or users between two or more versions of a page, feature or message and measure which version performs better on a goal such as signups, purchases or retention. Good A/B testing software also handles targeting, statistics and reporting, so you can trust that a winner is real and not random noise.
There are two broad types. Website A/B testing tools such as Optimizely Web, AB Tasty, Convert and Kameleoon change pages in the browser with a visual editor, which suits marketers and CRO teams. Experimentation platforms such as GrowthBook, Statsig, PostHog and LaunchDarkly run server-side A/B testing on feature flags, which suits product and engineering teams. Most tools in both groups also work as multivariate testing tools, comparing several changes at once. Many companies, and some tools, cover both.
Best A/B testing tools compared
| # | Tool | Best for | Free plan | Paid plans from | Our rating |
|---|---|---|---|---|---|
| 1 | Optimizely |
Enterprise web and feature tests | No | Custom (annual) | ★4.4 |
| 2 | AB Tasty |
Ecommerce tests and personalization | No | Custom (annual) | ★4.3 |
| 3 |  Convert |
Privacy-first, flicker-free tests | No (free trial) | By tested users/mo | ★4.5 |
| 4 |  VWO |
Tests plus heatmaps and recordings | Free trial | By tracked users (annual) | ★4.3 |
| 5 | Kameleoon | AI tests and strict compliance | No | Custom (annual) | Not yet reviewed |
| 6 | GrowthBook |
Free, open-source experimentation | Yes (Starter + self-host) | $20/user/mo | ★4.7 |
| 7 |  PostHog |
Tests plus analytics and replay | Yes (1M events/mo) | Usage-based | ★4.6 |
| 8 |  Statsig |
Product experiments at scale | Yes (Developer plan) | Pro by event volume | ★4.6 |
| 9 |  Unbounce |
Landing page tests for paid ads | No (14-day trial) | $29/mo (tests from $149/mo) | ★4.4 |
| 10 | LaunchDarkly | Feature flags with experiments | Yes (Developer plan) | Usage-based | Not yet reviewed |
Our rating comes from MakeSuccessOnline's hands-on reviews. Prices are the cheapest paid plan, billed monthly unless marked annual, checked November 2026.
The 10 best A/B testing tools in 2026
Website testing tools for marketers and experimentation platforms for product teams solve different problems. We ranked both, and each tool below leads a specific job.
#1Best overall for enterprise experimentation programs
Optimizely
An enterprise experimentation platform that runs A/B, multivariate and feature tests across websites and apps.
- Paid plans from
- Custom (annual)
- Free plan
- No
- Best for
- Mid-market and enterprise marketing, product and engineering teams
- Works on
- Web (SaaS), SDKs for web, mobile and server-side languages
Optimizely is one of the most mature A/B testing platforms and the default shortlist pick for large experimentation programs. Marketers use Web Experimentation to build client-side A/B, multivariate and multi-page tests in a visual editor or with custom code, while product teams use Feature Experimentation to test new features behind flags.
Its biggest strength is trust in the results. Stats Engine uses sequential statistics with false discovery rate control, so teams can watch tests without the peeking problems that trip up simpler tools. Add personalization, multi-armed bandits, warehouse-native analytics and program management, and you have a platform built for companies running many tests at once across teams.
Key features
- Web ExperimentationBuilds client-side A/B, multivariate and multi-page tests with a visual editor or custom code, so marketers can test pages without waiting on a developer sprint.
- Feature ExperimentationUses feature flags and SDKs to run server-side and mobile experiments and roll out features gradually, which lets product teams test pricing logic, onboarding and algorithms.
- Stats EngineApplies sequential statistics with false discovery rate control, so you can check results at any time without inflating false positives.
- Multi-armed banditsShifts traffic toward better-performing variations during a test, useful for short campaigns where you care more about conversions than learning.
- Program managementPlans, prioritizes and documents your testing roadmap and results in one place, so learnings are not lost when people change roles.
Pricing
| Plan | Price | What you get |
|---|---|---|
| Web Experimentation | Custom (annual) | Visual editor, A/B and multivariate tests, Stats Engine, personalization add-ons; priced by traffic |
| Feature Experimentation | Custom (annual) | Feature flags, server-side and mobile experiments, SDKs; priced by monthly active users |
| Analytics and other DXP products | Custom | Warehouse-native analytics, CMS, commerce and content marketing products |
Optimizely does not publish prices; all products are quoted annually based on traffic or monthly active users. Plans change often, so check the vendor's pricing page before you buy.
Pros and cons
Pros
- Covers marketing-led and engineering-led testing in one vendor
- Trusted sequential statistics engine
- Strong enterprise security and support
- Part of a wider suite with CMS, commerce and analytics
Cons
- No public pricing, and costs are high
- No free plan or self-serve entry tier
- Complex to set up and govern, and some products are separate licenses
Is it right for you?
Choose Optimizely ifYou run a large experimentation program across web and product teams and need statistics, governance and support that hold up at enterprise scale.
Look elsewhere ifYou are a small business or low-traffic site, or you want transparent self-serve pricing for occasional tests.
#2Best for ecommerce testing and personalization
AB Tasty
A platform for running A/B tests, personalization campaigns and feature experiments on websites and apps.
- Paid plans from
- Custom (annual)
- Free plan
- No
- Best for
- Mid-market and enterprise marketing, ecommerce and product teams
- Works on
- Web (SaaS), SDKs for server-side and mobile
AB Tasty is an experimentation and personalization platform with a strong ecommerce focus, which makes it one of the better A/B testing tools for ecommerce marketing teams. You build variations by pointing and clicking on the page, add banners, countdowns or pop-ins from a widget library, and run A/B, split URL and multivariate tests without writing code. Developers still get a code editor when a test needs it.
It stands out when testing and personalization go together. Once a variation wins, you can target it to segments based on behavior, geography or traffic source. A separate Feature Experimentation and Rollouts product adds flags and server-side tests, so product teams can work in the same platform as the marketing team.
Key features
- Visual editorBuilds test variations by pointing and clicking on the page, with a code editor for developers, so marketers can launch most tests themselves.
- A/B, split and multivariate testsSupports the main client-side test types, from a simple headline test to a full redesign on a separate URL.
- Widget libraryAdds ready-made banners, countdowns and pop-ins without coding, which is handy for testing promotions and urgency messages.
- PersonalizationShows targeted experiences to segments based on behavior, geography, traffic source and other criteria, so winning ideas can be rolled out to the right visitors.
- Bayesian statisticsReports results as probabilities and gain ranges, which makes it easier to explain a result to stakeholders who are not statisticians.
Pricing
| Plan | Price | What you get |
|---|---|---|
| Web Experimentation & Personalization | Custom (annual) | Visual editor, A/B, split and multivariate tests, personalization and widgets; priced by monthly traffic |
| Feature Experimentation & Rollouts | Custom (annual) | Feature flags, server-side and mobile experiments, progressive rollouts |
AB Tasty prices are quoted on request and based on monthly traffic. Plans change often, so check the vendor's pricing page before you buy.
Pros and cons
Pros
- Marketer-friendly visual editor and widgets
- Testing, personalization and feature flags in one platform
- Strong ecommerce focus
- Easy-to-read Bayesian reporting
Cons
- No public pricing or free plan
- Costs suit mid-market and enterprise budgets
- Client-side tests can flicker if not configured well
Is it right for you?
Choose AB Tasty ifYou run an ecommerce or marketing team that wants to test and personalize pages without relying on developers for every change.
Look elsewhere ifYou have a low-traffic site, want transparent self-serve pricing, or prefer open-source developer tooling.
#3Best for privacy-focused teams and CRO agencies
Convert
A privacy-focused A/B testing and personalization tool for websites, known for flicker-free tests and transparent plans.
- Paid plans from
- By tested users/mo
- Free plan
- No (free trial)
- Best for
- Agencies, CRO specialists and mid-sized ecommerce and SaaS companies
- Works on
- Web (SaaS)
Convert is a website A/B testing tool for teams that want serious testing features without an enterprise contract. You can build variations visually or with HTML, CSS and JavaScript, run A/B, split URL, multivariate and multi-page tests, and target them by location, device, cookies, behavior, data layer values or custom JavaScript conditions.
Two things set it apart. Its script is built to avoid the flash of original content that can bias client-side tests, and it is designed for GDPR and CCPA, with options such as no third-party cookies and data stored in the EU or US. That combination makes it a strong fit for EU companies and for CRO agencies managing many client sites.
Key features
- Flicker-free loadingThe tracking script is built to avoid the flash of original content, which protects both user experience and the accuracy of your results.
- A/B, split URL and multivariate testingRuns the standard test types on any website, including multi-page tests across a checkout or signup flow.
- Advanced targetingTargets tests by location, device, cookies, behavior, data layer values and custom JavaScript, so you can test on exactly the right audience.
- Frequentist and Bayesian statisticsLets you choose the statistical approach and settings that fit your testing program instead of forcing one method.
- Privacy complianceDesigned for GDPR and CCPA, with options such as no third-party cookies and EU or US data storage.
Pricing
| Plan | Price | What you get |
|---|---|---|
| Growth | Higher | A/B, split URL and multivariate tests, visual editor, integrations; monthly or annual billing |
| Pro | Higher | Advanced targeting, more projects, multi-armed bandits, advanced reporting |
| Enterprise | Custom | High traffic volumes, SSO, dedicated support |
Convert prices plans by tested users per month, with monthly or annual billing. Free trial, no credit card required. Plans change often, so check the vendor's pricing page before you buy.
Pros and cons
Pros
- Flicker-free testing
- Strong privacy and compliance stance
- More transparent pricing than enterprise rivals
- Flexible targeting and statistics options
Cons
- No free plan
- Entry price is still high for small sites
- Fewer built-in AI and personalization features than enterprise suites
Is it right for you?
Choose Convert ifYou are a CRO agency or privacy-conscious mid-sized business that wants enterprise-grade web testing on self-serve plans.
Look elsewhere ifYou need full feature flagging for product teams, or your site has too little traffic for regular tests.
#4Best for pairing A/B tests with behavior research
VWO
An experimentation platform whose Insights product adds heatmaps, session recordings, form analytics, funnels and on-page surveys to VWO Testing.
- Paid plans from
- By tracked users (annual)
- Free plan
- Free trial
- Best for
- Marketing, CRO and product teams, from mid-sized businesses to enterprise
- Works on
- Websites and mobile apps
VWO, from Wingify, offers conversion rate optimization tools as separate products. VWO Testing runs the experiments, while VWO Insights handles the research: click, scroll and dynamic heatmaps, session recordings, form analytics, funnels and on-page surveys. Together they cover the full loop of finding a problem, forming a hypothesis and testing a fix.
That loop suits CRO teams. Instead of guessing what to test, you watch recordings of visitors dropping off a form or checkout step, ask them why with a survey, and send the idea to VWO Testing. It suits mid-sized and enterprise sites running an ongoing optimization program across web and mobile.
Key features
- Link to VWO TestingFindings from Insights can be turned into experiments in VWO Testing, VWO's A/B testing product, so research and tests live in one platform.
- HeatmapsClick, scroll and dynamic heatmaps show how visitors interact with each page, which helps you spot what to test first.
- Session recordingsReplays real visits with filters, so you can see exactly where people struggle before and after a test.
- Funnels and form analyticsTracks drop-off between journey steps and at individual form fields, pointing you to the leaks worth testing.
- On-page surveysAsks visitors questions on the page to learn why they behave as they do, which turns guesses into stronger hypotheses.
Pricing
| Plan | Price | What you get |
|---|---|---|
| Entry tier | Higher (annual) | Heatmaps and session recordings; priced by monthly tracked users |
| Higher tiers | Higher (annual) | Funnels, form analytics, surveys and more |
| Enterprise | Custom | Advanced features, security and support |
VWO Insights is priced on annual plans based on monthly tracked users, VWO Testing is sold as a separate product, and a free trial is available. Plans change often, so check the vendor's pricing page before you buy.
Pros and cons
Pros
- Research and testing in one platform
- Broad behavior toolset for finding test ideas
- Supports web and mobile
- Built for ongoing CRO programs
Cons
- Testing and Insights are separate products to buy
- Pricing rises with traffic and can be expensive at scale
- More complex than a simple heatmap or testing tool
Is it right for you?
Choose VWO ifYou run a CRO program and want heatmaps, recordings, surveys and A/B tests from one vendor so every test starts from real visitor data.
Look elsewhere ifYou only need a quick, cheap A/B test or a free heatmap tool for a small site.
#5Best for AI-assisted testing in regulated industries
Kameleoon
An experimentation platform for web, feature and AI-assisted tests and personalization for marketing and product teams.
- Paid plans from
- Custom (annual)
- Free plan
- No
- Best for
- Mid-market and enterprise marketing, product and engineering teams
- Works on
- Web (SaaS), SDKs for server-side and mobile
Kameleoon is an experimentation and personalization platform that lets marketing and product teams test in the same place. Web Experimentation covers client-side A/B and multivariate tests with a visual or code editor, and Feature Experimentation adds flags and SDKs for server-side, mobile and full-stack tests and rollouts, so engineers can test features without a separate vendor.
Its AI features are the main draw. Prompt-based experimentation lets a marketer describe a change in plain language and have AI build the variation, and AI-driven personalization targets visitors by their predicted likelihood to convert. With flicker-free delivery, several statistical methods and GDPR-focused data residency, it suits regulated companies that cannot compromise on privacy.
Key features
- Prompt-based experimentationLets marketers describe a variation in plain language and have AI build it on the page, which cuts the time from idea to live test.
- Hybrid experimentationMarketing and product teams work in one platform with shared data and reporting, so results are comparable across teams.
- Flicker-free deliveryLoads tests in a way designed to stop the original page flashing before the variation appears.
- Statistics optionsOffers frequentist, Bayesian and sequential testing, so you can match the method to the decision you are making.
- Privacy and complianceBuilt for GDPR compliance with data residency options, a key requirement for finance and healthcare companies.
Pricing
| Plan | Price | What you get |
|---|---|---|
| Web Experimentation | Custom (annual) | Visual editor, A/B and multivariate tests, targeting; priced by monthly unique users |
| Feature Experimentation | Custom (annual) | Feature flags, server-side and mobile experiments, SDKs |
| AI Personalization | Custom | AI-driven targeting and predictive personalization |
Kameleoon quotes all products on request, based on monthly unique users. Plans change often, so check the vendor's pricing page before you buy.
Pros and cons
Pros
- One platform for marketing and product experimentation
- AI helps build variations and personalize
- Strong privacy and data residency options
- Flexible statistical methods
Cons
- No public pricing or free plan
- Enterprise-level cost
- Learning curve for advanced features
Is it right for you?
Choose Kameleoon ifYou work in a regulated industry or larger company and want marketers and engineers testing on one platform with AI help.
Look elsewhere ifYou run simple, occasional tests on a small budget or want self-serve monthly plans.
#6Best open-source and warehouse-native option
GrowthBook
An open-source, warehouse-native platform for feature flags and A/B testing that you can self-host or use in the cloud.
- Paid plans from
- $20/user/mo
- Free plan
- Yes (Starter + self-host)
- Best for
- Product and engineering teams, data teams and startups
- Works on
- Web (cloud or self-hosted), SDKs for JavaScript, React, Python, Go, Ruby, PHP, Java, Kotlin, Swift and more
GrowthBook is an open-source A/B testing and feature flag platform that analyzes experiments using the data in your own warehouse, such as Snowflake, BigQuery, Databricks, Redshift or Postgres. You define metrics once in SQL, run tests through lightweight SDKs, and keep full control of your data, especially if you self-host.
It is the best free A/B testing tool for technical teams. Statistics are strong for the price, with Bayesian or frequentist engines, sequential testing and CUPED variance reduction to reach results faster. Automatic health checks catch problems like sample ratio mismatch, and the Pro plan adds a visual editor so non-developers can create front-end tests.
Key features
- Warehouse-native experimentationAnalyzes experiments using data already in your warehouse, so there is no separate event pipeline and your numbers match your other reporting.
- Open source and self-hostingThe core platform is open source and can run on your own infrastructure, which gives you full data control at no license cost.
- Bayesian and frequentist statisticsChoose your stats engine, with sequential testing and CUPED variance reduction to reach confident results with less traffic.
- Experiment health checksFlags issues such as sample ratio mismatch and multiple exposures automatically, so you do not ship a decision based on a broken test.
- Feature flagsTurn features on or off and roll them out to segments or percentages without redeploying, then run experiments on the same flags.
Pricing
| Plan | Price | What you get |
|---|---|---|
| Starter | $0 | Unlimited feature flags and experiments, core SDKs and warehouse connections for small teams; self-hosted open source is also free |
| Pro | $20/user/mo | Visual editor, advanced experimentation features, more users and support |
| Enterprise | Custom | SSO/SCIM, advanced permissions, audit logs, dedicated support |
List prices as of November 2026; plans change often, so check the vendor's pricing page before you buy. Free trial of Pro available.
Pros and cons
Pros
- Free open-source option with self-hosting
- Transparent per-seat pricing
- Keeps experiment data in your own warehouse
- Strong statistics and automatic health checks
Cons
- Needs a data warehouse and technical skill to get the most from it
- Less suited to marketers wanting a pure no-code tool
- Self-hosting adds maintenance work
Is it right for you?
Choose GrowthBook ifYou are a startup or data-savvy product team that wants free or low-cost experimentation on top of your own warehouse.
Look elsewhere ifYou are a marketing team without engineering or data support that wants a polished no-code testing suite.
#7Best for A/B testing inside product analytics
PostHog
An all-in-one, open-source platform for product analytics, session replay, feature flags, A/B testing and surveys.
- Paid plans from
- Usage-based
- Free plan
- Yes (1M events/mo)
- Best for
- Engineers, product teams and technical founders at startups and SaaS companies
- Works on
- Web app (US or EU cloud), SDKs for web, iOS, Android, React Native, Flutter and server languages, self-hosted option
PostHog is a product analytics platform with A/B and multivariate experiments built in. Instead of adding a separate testing tool, you run experiments alongside feature flags and measure results with the same trends, funnels and retention charts your product team already uses, then open session replays to see how people behaved in each variant.
For startups it is hard to beat on price. Every month includes 1M events, 5K recordings, 1M feature flag requests and 1,500 survey responses free, and you pay per unit only beyond that, with billing limits per product. Cloud hosting in the US or EU and an open-source self-hosted option help with data residency.
Key features
- ExperimentsRuns A/B and multivariate tests with results measured on PostHog analytics, so test metrics match your product dashboards.
- Feature flagsRolls features out to a percentage or segment of users and switches them off instantly, giving you control over who sees each variant.
- Session replayRecords real user sessions with console and network logs, so you can see why a variant won or lost.
- HeatmapsClick, scroll and rage-click heatmaps on your pages help you find what to test next.
- SurveysIn-app or on-site surveys link answers to user behavior, adding the why behind your test results.
Pricing
| Plan | Price | What you get |
|---|---|---|
| Free | $0 | Monthly allowance of 1M events, 5K recordings, 1M feature flag requests and 1,500 survey responses |
| Pay-as-you-go | Usage-based | Per-unit pricing beyond the free allowance, longer data retention, billing limits per product |
| Platform add-ons | Higher | Extra platform, security and support features for larger teams |
PostHog charges per unit only above its free monthly allowance, and you can set billing limits per product. Plans change often, so check the vendor's pricing page before you buy.
Pros and cons
Pros
- Experiments, analytics, replay and flags in one tool
- Large free allowance each month
- Transparent, usage-based public pricing
- US or EU hosting and an open-source option
Cons
- Costs are harder to predict as usage grows
- Needs technical setup to get the most from it
- Busy interface for marketers who just want a page test
Is it right for you?
Choose PostHog ifYou are an engineering-led startup or SaaS team that wants A/B testing, analytics and session replay without paying several vendors.
Look elsewhere ifYou are a non-technical marketer who wants a visual editor for landing page tests and a fixed monthly bill.
#8Best for high-volume product experimentation
Statsig
A product development platform for A/B testing, feature flags, product analytics and session replay on one data set.
- Paid plans from
- Pro by event volume
- Free plan
- Yes (Developer plan)
- Best for
- Engineering, product and data teams that run frequent experiments
- Works on
- Web console, SDKs for web, iOS, Android, React Native and server languages, warehouse-native option
Statsig is an experimentation platform for product and engineering teams. Feature gates control who sees a feature, experiments measure its impact, and product analytics and session replay sit on the same events, so there is one source of truth for every launch decision. It suits teams that ship and test new features every week.
The statistics are its strongest point. CUPED variance reduction and sequential testing help you reach reliable results faster, a shared metrics catalog keeps definitions consistent, and the Warehouse Native option runs analysis on your own data. OpenAI acquired Statsig in September 2025, and the product continues to operate and serve customers.
Key features
- ExperimentsA/B and multivariate tests with a stats engine that includes CUPED variance reduction and sequential testing, for faster and more reliable results.
- Feature flagsGate features by user, segment or percentage and roll back instantly, so every release can double as a test.
- Product analyticsFunnels, retention, user journeys and dashboards built on the same events as experiments, so results line up with product reporting.
- Warehouse NativeRuns experiment analysis directly on data in your own warehouse, which suits companies that keep metrics in Snowflake or BigQuery.
- Metrics catalogDefines shared metrics once and reuses them across experiments and dashboards, which avoids arguments over what a number means.
Pricing
| Plan | Price | What you get |
|---|---|---|
| Developer | $0 | Unlimited feature flags, experiments, product analytics and session replay within a free monthly event allowance |
| Pro | Higher | More events and replays, plus more features for teams; priced by event volume |
| Enterprise | Custom | Warehouse-native option, advanced controls and support |
Statsig prices paid plans by event volume. Plans change often, so check the vendor's pricing page before you buy.
Pros and cons
Pros
- Strong experimentation statistics
- Generous free Developer plan
- Flags, tests, analytics and replay in one tool
- Warehouse-native option for data teams
Cons
- Built for technical teams, less friendly to marketers
- No visual web editor for landing page tests
- OpenAI ownership raises roadmap and data questions for some buyers
Is it right for you?
Choose Statsig ifYour engineering and product teams run many feature experiments and want rigorous statistics with a free way to start.
Look elsewhere ifYou are a marketer who wants to test headlines and layouts in a no-code page editor.
#9Best for landing page A/B testing
Unbounce
A landing page builder for paid campaigns, with AI page generation, A/B testing, Smart Traffic, popups and sticky bars.
- Paid plans from
- $29/mo (tests from $149/mo)
- Free plan
- No (14-day trial)
- Best for
- Marketers, SaaS teams, ecommerce brands and agencies running paid ad campaigns
- Works on
- Web (hosted pages), WordPress plugin
Unbounce is a landing page builder for paid campaigns that includes A/B testing, so PPC marketers can build a page, create variants and split traffic without adding a separate testing tool. A hybrid builder generates a page from a prompt and lets you fine-tune it with drag and drop, which speeds up building test variants.
Testing starts on the Experiment plan, which adds unlimited A/B tests with manual traffic splits and confidence intervals, plus dynamic text replacement to match the ad a visitor clicked. The Optimize plan adds Smart Traffic, which routes each visitor to the variant most likely to convert and starts working after a small number of visits.
Key features
- A/B testingRuns unlimited tests and variants with manual traffic splits and confidence intervals, so you can prove which headline or offer wins before scaling ad spend (Experiment plan and up).
- Smart TrafficUses AI to route each visitor to the variant most likely to convert for someone like them, and starts working after a small number of visits (Optimize plan and up).
- Dynamic text replacementSwaps words on the page to match the keyword or ad a visitor clicked, keeping ad and page aligned.
- Hybrid builderGenerates a page from a prompt, then lets you fine-tune with drag and drop or revise a single block with AI, which speeds up building variants.
- Popups and sticky barsShows targeted offers or lead forms with exit-intent, scroll or delay triggers and URL or UTM targeting.
Pricing
| Plan | Price | What you get |
|---|---|---|
| Starter | $29/mo | 1 domain, 500 visitors/mo, up to 5 pages, AI copywriting and lead forms (no A/B testing) |
| Build | $99/mo | 20,000 visitors/mo, unlimited pages, custom code and scripts |
| Experiment | $149/mo | Unlimited A/B testing and dynamic text replacement, 3 users, 2 domains |
| Optimize | $249/mo | 50,000 visitors/mo, Smart Traffic, page scheduling and advanced triggers |
| Concierge | Custom | 100,000+ visitors/mo, implementation services and a dedicated success manager |
List prices billed monthly as of November 2026; plans change often, so check the vendor's pricing page before you buy. 14-day free trial, no card required.
Pros and cons
Pros
- Build and test landing pages in one tool
- Smart Traffic helps even at low traffic
- Dynamic text replacement for paid search
- Unlimited conversions on every plan
Cons
- A/B testing starts on the third plan at $149/mo
- Tests are built for Unbounce-hosted pages, not your main site
- Starter is very limited, with 5 pages and 500 visitors
Is it right for you?
Choose Unbounce ifYou run paid campaigns and want to build and A/B test landing pages yourself without a developer or a separate testing tool.
Look elsewhere ifYou need to test pages on your main website, app or Shopify store theme.
#10Best for engineering teams testing on feature flags
LaunchDarkly
A feature flag platform for releasing, targeting and rolling back features, with an experimentation add-on for A/B tests on flags.
- Paid plans from
- Usage-based
- Free plan
- Yes (Developer plan)
- Best for
- Software engineering and product teams at SaaS and enterprise companies
- Works on
- Web dashboard, SDKs for server, client and mobile, API
LaunchDarkly is a feature management platform first and an A/B testing tool second. Engineers wrap new code in feature flags, then target, roll out and roll back features without redeploying. Experimentation, sold as an add-on, lets the same flags power A/B and multivariate tests that measure a feature's effect on your metrics.
It makes sense for teams that already release through flags and want to measure impact without adding another vendor. Percentage rollouts limit the risk of a bad release, a kill switch turns off a broken feature instantly, and audit logs and approvals suit regulated teams. It is not built for marketers testing headlines or landing pages.
Key features
- ExperimentationRuns A/B and multivariate experiments on flag variations and measures the effect on metrics, sold as an add-on rather than in every plan.
- Targeting rulesServes a flag variation to specific users, segments or attributes, which makes beta programs and targeted tests easy.
- Percentage rolloutsReleases a feature to a percentage of users and raises it step by step, limiting the impact of a bad release.
- Kill switch and rollbackTurns off a misbehaving feature instantly from the dashboard instead of waiting for a hotfix deploy.
- Audit log and approvalsTracks every flag change and can require approvals in sensitive environments, which suits regulated teams.
Pricing
| Plan | Price | What you get |
|---|---|---|
| Developer | $0 | Feature flags and SDKs for small projects, with limited usage |
| Foundation | Higher (usage-based) | Core feature management for teams; priced by service connections and client-side MAU |
| Enterprise | Custom | Advanced governance, approvals, SSO and scale |
| Guardian | Custom | Release monitoring and automatic rollback on top of Enterprise |
LaunchDarkly uses usage-based pricing, and experimentation is a paid add-on. A free trial is available. Plans change often, so check the vendor's pricing page before you buy.
Pros and cons
Pros
- Mature, market-leading feature flag platform
- Experiments run on the same flags used for releases
- Wide SDK coverage across languages and mobile
- Strong governance for large engineering teams
Cons
- Experimentation is a paid add-on
- Usage-based pricing can be hard to predict
- No visual editor for page-level A/B tests
Is it right for you?
Choose LaunchDarkly ifYour engineering team already ships through feature flags and wants to measure the impact of each release with experiments.
Look elsewhere ifYou are a marketer testing headlines, landing pages or checkout copy.
Best A/B testing tool by need
- Enterprise experimentation programsOptimizely
- Ecommerce testing and personalizationAB Tasty
- CRO agencies and privacy-first teamsConvert
- Tests backed by heatmaps and recordingsVWO
- Regulated industries and AI-built variationsKameleoon
- Free, open source A/B testingGrowthBook
- Startups wanting analytics plus testsPostHog
- High-volume product experimentsStatsig
- Landing page tests for paid adsUnbounce
What to look for in an A/B testing tool
- Visual editor or SDKsMarketers need a point-and-click editor to change copy and layouts. Product teams need SDKs and feature flags for server-side and mobile tests. Pick the tool that matches who will build the tests.
- Trustworthy statisticsLook for sequential testing, Bayesian reporting or CUPED variance reduction. These let you check results early or reach significance with less traffic without inflating false positives.
- Flicker-free deliveryClient-side tests can briefly show the original page before the variation loads. That flicker hurts user experience and can bias results, so check how each tool prevents it.
- Targeting and personalizationGood targeting lets you test on the right audience, such as mobile visitors or paid traffic, and then roll winners out to specific segments.
- Privacy and data controlCheck cookie use, EU or US data storage and whether results can be analyzed in your own warehouse. This matters for GDPR and regulated industries.
- Pricing modelTools charge by traffic, tracked users, events or seats. Model your real monthly traffic before you sign, because costs rise fast on traffic-based plans.
How much do A/B testing tools cost in 2026?
A/B testing tools range from free open-source software to enterprise contracts quoted by traffic. Most website testing tools charge by monthly visitors or tested users, while product experimentation platforms charge by events, seats or monthly active users.
| Tier | Typical price | Tools at this level | Who it suits |
|---|---|---|---|
| Free | $0 | GrowthBook Starter and self-hosted, PostHog, Statsig Developer, LaunchDarkly Developer | Startups and product teams with developers |
| Self-serve paid | $20/user/mo to $249/mo | GrowthBook Pro, Unbounce Experiment and Optimize | Small teams, startups and paid-ads marketers |
| Usage-based and mid-market | Priced by events, tested users or traffic | PostHog and Statsig paid plans, LaunchDarkly Foundation, Convert, VWO | Growing product teams, CRO agencies and mid-sized ecommerce and SaaS teams |
| Enterprise | Custom annual contract | Optimizely, AB Tasty, Kameleoon, LaunchDarkly Enterprise | Large companies running testing programs across teams |
Entry prices and pricing models from vendor plan information, November 2026.
Before you compare A/B testing tool pricing, check your traffic. A test needs enough visitors and conversions per variation to reach a reliable result, so a low-traffic site paying for an enterprise license gets little value. Start free with GrowthBook, PostHog or Statsig if you have developers, or use Unbounce for landing pages, and move to a traffic-based contract only when you are running tests every month.
How we chose the best A/B testing tools
We started with the A/B testing and experimentation tools in the MakeSuccessOnline directory and added well-known platforms we have not yet reviewed, such as Kameleoon and LaunchDarkly. We assessed each tool from hands-on reviews where available, vendor documentation and current plan information, scoring them on the criteria below for both marketing-led and product-led testing. Pricing and plans were checked in November 2026.
- Testing capabilityTest types, visual editor, server-side and mobile support, and targeting.25%
- Statistical rigorSequential, Bayesian or CUPED methods and automatic health checks.20%
- Ease of useHow quickly a marketer or developer can launch a valid test.20%
- Pricing and valueFree plans, transparency and cost at realistic traffic levels.15%
- Performance and privacyFlicker-free delivery, data residency and GDPR options.10%
- Integrations and dataAnalytics, warehouse and CMS connections for reporting results.10%
How to choose an A/B testing tool
- Decide who builds the testsIf marketers will run tests, prioritize a visual editor. If engineers will, prioritize SDKs, feature flags and server-side testing.
- Check your trafficEstimate visitors and conversions per month on the pages you want to test. Low traffic means fewer, bolder tests and a cheaper tool.
- Match the pricing model to your growthTraffic, tracked users, events and seats scale differently. Model next year's traffic, not just this month's.
- Test for flicker and speedRun a trial test on a real page and watch for the original content flashing before the variation loads.
- Review the statisticsMake sure you understand how the tool declares a winner and whether you can check results early without false positives.
- Plan where results liveConnect the tool to your analytics or warehouse so test results match the numbers your team already trusts.
Check during the free trial
- Can a marketer launch a test without a developer?
- Does the page flicker before the variation loads?
- How does the tool decide a winner, and can you check early?
- What will it cost at your real monthly traffic?
- Can results be sent to your analytics or warehouse?
Red flags
- Declares winners after a few dozen conversions
- No explanation of its statistical method
- Visible flicker on your pages during the trial
- Pricing that jumps sharply with a small traffic increase
- No way to export raw experiment data
A/B testing tools FAQ
What are the best A/B testing tools?
The best A/B testing tools in 2026 are Optimizely for enterprise programs, AB Tasty for ecommerce testing and personalization, Convert for privacy-focused teams and agencies, VWO for pairing tests with behavior research, and GrowthBook for a free open-source option. Product teams should also look at PostHog and Statsig, and paid-ads marketers at Unbounce.
What is the best free A/B testing tool?
GrowthBook is the best free A/B testing tool for most technical teams, because its open-source core is free to self-host and the cloud Starter plan costs nothing. PostHog includes experiments in a free monthly allowance of 1M events, and Statsig's free Developer plan includes unlimited flags and experiments within its event limit. All three need developer help to set up.
What is the best Google Optimize alternative?
Google Optimize shut down in 2023, so former users need a new tool. Among Google Optimize alternatives with a visual editor for marketers, Convert suits mid-sized sites, while AB Tasty and Optimizely suit larger budgets. VWO is worth a look if you also want heatmaps and session recordings. If you have developers and want a free option, GrowthBook and PostHog are the strongest replacements.
VWO vs Optimizely: which is better?
Optimizely is better for large companies that need web and feature experimentation, enterprise governance and a sequential stats engine in one platform. VWO is better for CRO teams that want heatmaps, session recordings, funnels and surveys alongside their tests, so each experiment starts from real visitor behavior. Both quote prices based on traffic.
How much do A/B testing tools cost?
A/B testing tools cost anything from $0 to large enterprise contracts. GrowthBook, PostHog and Statsig have free plans, GrowthBook Pro is $20 per user a month, and Unbounce includes A/B testing from $149 a month. Convert and VWO price by tested or tracked users, while Optimizely, AB Tasty and Kameleoon are quoted annually.
How do I choose an A/B testing tool?
To choose an A/B testing tool, start with who will build tests. Marketers need a visual editor, while engineers need SDKs and feature flags. Then check your traffic, since low-traffic sites rarely reach significance, and compare pricing at your real monthly volume. Finally, trial the tool on a real page to check for flicker and to see how clearly it reports results.
How long should an A/B test run?
Run an A/B test until it reaches the sample size your tool recommends and for at least one full week, ideally two, so you capture weekday and weekend behavior. Stopping as soon as a result looks significant leads to false winners, unless your tool uses sequential statistics designed for early checks, as Optimizely, Statsig and GrowthBook do.
What is the difference between client-side and server-side A/B testing?
Client-side testing changes the page in the visitor's browser, usually with a visual editor, which suits marketers testing copy and layouts. Server-side testing decides the variation in your code before the page loads, usually with feature flags, which suits product teams testing features, pricing or algorithms. Server-side tests avoid flicker but need developer time.
About the reviewer
Editor & Reviewer, MakeSuccessOnline
William Harrison is an editor and reviewer at MakeSuccessOnline. He reviews each tools ranking before it goes live, checking plans, prices, free tiers and features against the tool's own documentation, and keeps rankings current as tools change.