Lightweight, modern open-source CAPTCHA alternative designed using SHA-256 proof-of-work and JS instrumentation
Cost / License
- Free
- Open Source
Application type
Platforms
- Self-Hosted
- Docker
Portugal
EU
Private Captcha AlternativesAnti-Spam Tools and other similar apps like Private Captcha
Apps similar to Private Captcha include Cap Captcha, which is free and open source. Other options are Anubis, reCAPTCHA, ALTCHA and Procaptcha. Anti-Spam Tools like Private Captcha are a crowded field, with more than 25 alternatives for the web, self-hosting, Windows and Linux.
Alternatives list
58 Anubis alternativesApplies sha256 proof-of-work challenges to incoming HTTP requests, targeting AI crawlers, bots that ignore robots.txt, and automated scrapers, protecting server resources and preventing unwanted search engine indexing for privacy-focused sites.
Cost / License
- Free Personal
- Open Source (MIT)
Application typeApplication types
Platforms
- Self-Hosted
- Go (Programming Language)
- Docker
Canada
35 reCAPTCHA alternativesreCAPTCHA is a free service that protects your site from spam and abuse, using risk analysis techniques to tell humans and bots apart.
Cost / License
- Freemium
- Proprietary
Application type
Platforms
- Online
United States
26 ALTCHA alternativesALTCHA is a privacy-first solution built to help developers and website owners stop bots, spam, and automated abuse — without making things harder for real users. It replaces traditional CAPTCHA systems with a smarter, quieter approach to verification and threat detection.
Czechia- EU
Prosopo Procaptcha redefines user verification with a unique approach that emphasizes privacy and security. It's a pioneering solution designed to offer an alternative to conventional CAPTCHA systems that often compromise user privacy.
Cost / License
- Freemium
- Open Source (Apache-2.0)
Application typeApplication types
Platforms
- Online
- Software as a Service (SaaS)
- Wordpress
United Kingdom
+3
Cost / License
- Freemium
- Proprietary
Platforms
- Online
- Software as a Service (SaaS)
South Korea
+4
A lightweight (~217 bytes vanila JS at frontend) and privacy-friendly plugin to prevent spam comment in the default commenting system of WordPress. Works instantly. No settings required. No captcha.
DataDome is the only bot protection solution delivered as-a-service. Unlike competing products, it requires no architecture changes or DNS rerouting, and will never be a single point of failure.
Cost / License
- Paid
- Proprietary
Application type
Platforms
- Windows
- Linux
- Software as a Service (SaaS)
France- EU
Turnstile is Cloudflare's smart CAPTCHA alternative. It automatically chooses from a rotating suite of non-intrusive browser challenges based on telemetry and client behavior exhibited during a session.
Cost / License
- Free
- Proprietary
Platforms
- Online
- JavaScript
- Software as a Service (SaaS)
The Arkose Labs platform undermines the economic drivers behind fraud until perpetrators are compelled to abandon attacks. Real-time risk classification of traffic with interactive enforcement challenges, the solution defeats automated attacks...
Cost / License
- Paid
- Proprietary
Platforms
- Software as a Service (SaaS)
- United States
