Introduction

Note: A variation of the original CAPTCHA technology by one of the original developers can also be found at recaptcha.net. This is not affiliated with NAR/CRT.

The reCaptcha project is a reimplementation of CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) technology that can be one piece of a broader anti-screen scraping strategy. Distorted dictionary words are presented to those who access your website. If they can successfully enter the word, they are probably human. Special Tags are placed in static HTML files used to allow customization of the tests.

The project is a reimplementation of a visual CAPTCHA based on the research work published through the Carnegie Mellon School of Computer Science CAPTCHA Project. This technology provides an excellent and accurate ability to detect scripts and other programs that attempt to access your site.

Features

• Easy to integrate into existing sites.
• Customizable presentation layout.
• Customizable dictionary.
• Horizontal and Vertical distortion.
• Non-dictionary word created from real dictionary words.
• Random color variations for each character.
• Random font variations words.
• Random image backgrounds.
• Cross platform. Runs on Microsoft Windows, Linux, Unix, Mac OS X, and anywhere else a 1.4 version of Java is available.
• Minimal external installation requirements. Standalone or Servlet versions are available.

News

• 17 jun 2004: Version 1.0 Beta released.
• 28 jun 2004: Version 1.0 Beta 2 released.
• 29 sep 2004: Version 1.0 Beta 3 released.