A Private Captcha alternative with a free plan
Updated
Both stop bots on web forms. The differences are in what the visitor sees, what runs on your page, what the free plan includes, and where the data is stored.
Where Private Captcha is better
Private Captcha is close to Bot403: a proof of work, a small company in the EU, and a real person who answers email. It does more in some areas. It has plugins for WordPress, Magento 2 and TYPO3, a widget in 13 languages, a self-hosted edition, and a compute- and memory-hard proof of work. If you want these plugins, or want to run it on your own server, Private Captcha is the better pick.
Where Bot403 is better
Bot403 has a free plan: 5,000 checks a month on 2 sites, with no time limit and no card. Private Captcha has a 14-day trial. The Bot403 Starter plan costs €3 a month for 50,000 checks, VAT included. At Private Captcha, 50,000 requests cost €109 a month, or €89 a month billed yearly, before VAT. The Bot403 script is always invisible.
Side by side
The facts come from the public pages of Private Captcha (https://privatecaptcha.com/pricing/pricing.md, https://privatecaptcha.com/, https://privatecaptcha.com/faq/, https://privatecaptcha.com/about/, https://docs.privatecaptcha.com/docs/reference/widget-options/, https://github.com/PrivateCaptcha/PrivateCaptcha), checked on 2026-10-23. "Not stated" means the page does not say. If something changed, email me. Then I will correct it.
| Capability | Bot403 | Private Captcha |
|---|---|---|
| Method | proof of work | proof of work |
| Company | one person in the EU | Intmaker OÜ, Estonia |
| Free plan | 5,000 checks, 2 sites, no card | a 14-day trial, no card |
| First paid plan | €3 a month for 50,000 on 10 sites, VAT included | €6 a month for 1,000 (€5 billed yearly), plus VAT |
| 5,000 a month | free | €11 a month (€9 billed yearly), plus VAT |
| 50,000 a month | €3 a month, VAT included | €109 a month (€89 billed yearly), plus VAT |
| What visitors see | nothing | a widget by default, also popup and hidden modes |
| Self-hosting | no | yes, free for non-commercial use (PolyForm Noncommercial) |
| Plugins | none | WordPress, Magento 2, TYPO3 |
| Cookies | none | none, except a signed cookie for its scraping protection |
Switch in 10 minutes
Remove the Private Captcha script and widget from the page. Add one script tag with your public key. On the server, replace the Private Captcha verify call with a POST to /api/v1/verify. The verify page has the request for Node.js, Bun, Deno, Hono, Next.js, Cloudflare Workers, PHP, Python, Go and Ruby. The form fields stay as they are.