Open Source Alternatives to reCAPTCHA

A web security service that protects sites from spam and abuse by analyzing user interactions and distinguishing humans from bots using risk analysis techniques.

Whether you want to cut software costs or escape vendor lock-in, these open source alternatives to reCAPTCHA give you an option you fully own. You can self-host them, so your data stays on infrastructure you control. This page lists 2 open source alternatives to reCAPTCHA. The most popular are Cap and ALTCHA. Most use the Apache-2.0 or MIT license, and 2 offer an official Docker image.