RiskCaptcha provides math and image-based CAPTCHA verification through a simple API. Protect your forms, login pages, and APIs from bots with zero configuration.
Built for developers who need simple, reliable bot protection without the complexity.
Dynamic arithmetic problems that are easy for humans but difficult for bots. Fully randomized with multiple operators.
Blurred, distorted text rendered as SVG images. Includes noise and visual distortion to defeat OCR bots.
Built-in session tokens that persist for 1 hour after verification. Validate sessions with a single API call.
Deployed on Cloudflare Workers for sub-50ms response times. Auto-scaling, no infrastructure to manage.
Full CORS support for cross-origin requests. Use from any frontend, mobile app, or backend service.
Tokens expire after 5 minutes. One-time use verification. Session tokens with automatic cleanup.
Simple REST endpoints for CAPTCHA generation and verification.
Generate a math CAPTCHA with a random arithmetic problem.
Generate an image CAPTCHA with blurred, distorted text.
Verify a CAPTCHA answer and receive a session token.
Validate an existing session token.
Test the CAPTCHA service right here. No setup required.
/captcha/validate-session to check if a session is still valid.