You don’t need ten tools to start CRO. You need to see what visitors do, measure what happens, and test your best ideas.
Here’s the short list we’d actually recommend, what each tool is good at, and which ones are free. Prices and plans change often, so we date every check.
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The quick comparison
| Tool | Type | Best for | Free option |
|---|---|---|---|
| Microsoft Clarity | Heatmaps and recordings | Everyone, especially on a budget | Free forever |
| Google Analytics 4 | Analytics | Default website analytics | Free |
| Google Tag Manager | Tag management | Managing tracking and test tags | Free |
| Hotjar | Heatmaps, recordings, surveys | Marketers and designers | Free plan |
| Mida | A/B testing | Small teams starting to test | Free plan |
| GrowthBook | A/B testing and feature flags | Product and engineering teams | Free plan |
| PostHog | Product analytics, replay, experiments | SaaS teams | Free monthly allowance |
| Convert | A/B testing | Dedicated testing programs | Free trial |
| VWO by Wingify | Testing, insights, personalization | Growing teams wanting a suite | Free trial |
| Optimizely | Enterprise experimentation | Large organisations | On request |
| Usermaven | Privacy-friendly analytics | Simple website and product analytics | Paid plans |
Which should I pick?
Just starting? Install Google Analytics 4 through Google Tag Manager, add Microsoft Clarity, and watch 20 recordings of your most important page this week. That costs nothing and teaches you more than any paid tool on day one.
Ready for your first A/B test? Check your traffic with the sample size calculator first. If the numbers work, a free-plan tool like Mida, GrowthBook or PostHog is plenty for the first tests.
Testing every month? Move to a dedicated tool like Convert or VWO when you need better targeting, more tests at once, stronger support or more seats.
Enterprise? Optimizely, or server-side testing with feature flags (GrowthBook, PostHog), fits governance-heavy teams.
Summary: start free with GA4, Tag Manager and Clarity; add a testing tool once you have ideas worth testing and enough traffic to test them.
A/B testing and experimentation
Run experiments on your site or app. Pick by your traffic, your team’s skills and whether you test in the browser or in code.
Convert
Free trialBest for: Teams that want a dedicated, privacy-focused A/B testing tool with strong support.
- Visual and code editors
- A/B, split URL and multivariate tests
- Privacy-first approach
From $299/month billed annually ($399 monthly). Free trial available. Checked 4 November 2026.
Mida
Free planBest for: Small teams and startups that want to start testing for free.
- Lightweight script
- AI-assisted variation building
- Free plan to get started
Free plan available; paid plans scale with monthly tracked users. Checked 4 November 2026.
VWO by Wingify
Free trialBest for: Growing teams that want testing, behaviour insights and personalization in one suite.
- Testing, insights and personalization
- Visual editor plus server-side options
- Large knowledge base
Custom pricing based on your needs. Free trial available. Checked 4 November 2026.
GrowthBook
Free planBest for: Product and engineering teams that test in code with feature flags.
- Open source, can be self-hosted
- Feature flags plus experiment analysis
- Works with your data warehouse
Free cloud plan (no credit card); paid plans from $40 per seat per month. Checked 4 November 2026.
PostHog
Free planBest for: SaaS teams that want analytics, recordings, feature flags and experiments in one place.
- Experiments and feature flags
- Product analytics and session replay
- Generous free monthly allowance
Free monthly allowance (no credit card); usage-based pricing above it. Checked 4 November 2026.
Optimizely
PaidBest for: Large organisations running experimentation at enterprise scale.
- Web and feature experimentation
- Enterprise governance
- Part of a wider digital experience platform
Enterprise pricing on request. Checked 4 November 2026.
Heatmaps and session recordings
See what visitors actually do: where they click, scroll, hesitate and rage-click.
Microsoft Clarity
Free planBest for: Anyone who wants heatmaps and recordings without paying a cent.
- Heatmaps and session recordings
- Rage-click and dead-click detection
- Free forever, no traffic limits
Free forever, no traffic limits. Checked 4 November 2026.
Hotjar (Contentsquare)
Free planBest for: Marketers and designers who want recordings, heatmaps and on-site surveys together.
- Recordings and heatmaps
- Surveys and feedback widgets
- Funnels and integrations
Free plan available; paid plans add more sessions and features. Checked 4 November 2026.
Analytics and tag management
Measure what happens, and manage your tracking without a developer for every change.
Google Analytics 4
Free planBest for: The default free analytics tool for most websites.
- Event-based tracking
- Funnel and path explorations
- Connects to Google Ads and BigQuery
Free. Checked 4 November 2026.
Google Tag Manager
Free planBest for: Managing all your tracking and testing tags in one place.
- Add and change tags without code releases
- Consent Mode support
- Preview and debug before publishing
Free. Checked 4 November 2026.
Usermaven
PaidBest for: Teams that want simple, privacy-friendly website and product analytics.
- Website and product analytics together
- Attribution reporting
- Keeps tracking when common ad blockers are on
Paid plans; see their site for current options. Checked 4 November 2026.
How we chose
We picked tools that cover the CRO workflow from research to testing, at different budgets. Plans and prices were read from each vendor’s own site on 4 November 2026; always check the current offer before you buy. We don’t rank tools by score, because the right tool depends on your traffic, team and stack.