Apps similar to Cloudflare Turnstile include Cap Captcha, which is free and open source. Other options are Anubis, reCAPTCHA, Private Captcha and ALTCHA. Anti-Spam Tools like Cloudflare Turnstile are a crowded field, with more than 25 alternatives for the web and self-hosting.
Anti-Spam Features. CleanTalk protects your website from spam bots and spam in Comments, Orders, Widgets, Registrations, Bookings, And any custom web form, Contact Emails, Subscriptions, Checks the existing comments and users for spam.
United States
Forum Fortress protects online forums from spam registrations, posts, profiles and signatures without forcing genuine users through CAPTCHA.
United Kingdom
reCaptcha plugin is an effective security solution that protects your WordPress website forms from spam entries while letting real people pass through with ease. It can be used for login, registration, password recovery, comments, popular contact forms, and others.
Ukraine
A zero database architecture, powered by a proprietary hybrid in-memory indexing engine algorithm, that enables CAPTCHA authentication to be performed using minimal data bits against server memory.
Privacy-first, self-hosted CAPTCHA for the modern web. No Google. No telemetry. No visual puzzles. Protect your software from bots without handing over your users' data to a third party.
Mexico
conCaptcha is a self-hosted captcha which is faster, more user-friendly and more customizable than other captchas - available for PHP and ASP.NET websites. Users no longer have to read any annoying text images, solve difficult math equations or play any puzzle games.
The visitor's browser silently solves a small proof-of-work challenge in a few milliseconds. Humans never see a CAPTCHA, while spam bots either fail or have to pay in computing power.
Germany
EU
Stop bots and fraudsters with invisible protection. Barrier-free bot protection without CAPTCHAs, GDPR-compliant and made in Germany.
GermanyEU
Protect your business from bots and spam while ensuring 100% data privacy compliance. No puzzles, no tracking – just invisible security that works.
NoBot CAPTCHA API is a developer-friendly alternative to Google reCAPTCHA that helps prevent automated bot traffic without compromising user privacy.
Austria
