head to head · open source
GrowthBook vs Cap
GrowthBook has 8,558 GitHub stars, 890 forks, 793 open issues and last shipped yesterday. Cap has 8,236 stars, 637 forks, 10 open issues and last shipped 5 days ago. GrowthBook leads on adoption by 4% (8,558 vs 8,236 stars). GrowthBook is written in TypeScript under a custom or non-standard licence; Cap is written in JavaScript under a custom or non-standard licence. GrowthBook has attracted 10% as many forks as stars, Cap 8%. GrowthBook was the more recently maintained of the two, and both are self-hostable with no licence fee.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| GrowthBook | Cap | |
|---|---|---|
| GitHub stars | ★ 8.6K | ★ 8.2K |
| License | Custom / other | Custom / other |
| Written in | TypeScript | JavaScript |
| Last push | 2026-11-02 | 2026-10-29 |
| Forks | ⑂ 890 | ⑂ 637 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick GrowthBook if
- You weight community size — 8.6K stars and counting
- You want the Custom / other license terms
- Your stack matches TypeScript
- You value the larger contributor base for long-term maintenance
pick Cap if
- You want the Cap feature set and don't need the biggest community
- You prefer the Custom / other license terms
- Your stack matches JavaScript
- You evaluated both and Cap fits your workflow better
About GrowthBook
Open Source Feature Flags, Experimentation, and Product Analytics Create a free GrowthBook Cloud account to get started quickly. Or run it yourself with: Then visit View the full Self Hosting Instructions for more details. This pulls our prebuilt public Docker image and needs no registry credentials. If you instead build the image from the Dockerfile in this repo, its hardened base images come from Docker's dhi.io registry, which requires a one time docker login dhi.io with any free Docker account — see Building from source. Our Philosophy The top 1% of companies spend thousands of hours building their own in…
read the full GrowthBook overview →
About Cap
Cap Cap is a lightweight, modern open source CAPTCHA alternative using proof of work and instrumentation challenges . It's fast, private, and extremely simple to integrate. Documentation Read the docs , try the demo or deploy on Railway What is Cap? Cap replaces visual captchas with modern, accessible and privacy preserving challenges. No images, no tracking, no dependencies, works everywhere. The default way to use Cap is with the Standalone Docker container. Learn more about how Cap works Why Cap? 250x smaller than hCaptcha 20kb, zero dependencies, loads in milliseconds Privacy first Cap doesn't send any…
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Frequently asked questions
Is GrowthBook or Cap more popular?
GrowthBook has 8,558 GitHub stars and Cap has 8,236. GrowthBook has the larger community by that measure.
Are GrowthBook and Cap free?
Neither GrowthBook nor Cap declares a licence in this registry, so check each project's own repository before relying on either for a commercial use. Both are free to self-host.
What is the difference between GrowthBook and Cap?
GrowthBook is written in TypeScript and Cap in JavaScript. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, GrowthBook or Cap?
Choose GrowthBook if you want the larger community (8,558 stars) or its Custom / other licence terms. Choose Cap if its feature set, stack or Custom / other licence fits better. Both are self-hostable.