GoCaptcha

Arkose MatchKey challenges provide a unique user experience, performance improvements, and powerful styling features. Traditional CAPTCHAs don’t work because bots get around them. But Arkose MatchKey challenges are designed to meet modern threats head-on by providing the best of defensibility, usability, and accessibility in one product. In fact, Arkose MatchKey is the strongest CAPTCHA ever made. Arkose MatchKey is a state-of-the-art series of challenges with industry-leading security. An unparalleled variety of 3D imagery. Our strongest challenges may produce more than 1,250 variations of a problem to solve. All are incredibly easy for legitimate users, but the variety makes it incredibly difficult to solve with automation. We use a key image to solve the largest problem with challenge design: Conveying instructions that are universally understandable across all languages and cultures. Large, aesthetically pleasing images are easy to see.

The TextCaptcha service provides access to textual CAPTCHA challenges via a simple JSON or XML API over HTTP. The question is the textual challenge that should be presented to the user. The answers are the MD5 hashes of correct lower cased answers: you should be able to check responses from real users you challenge with the question against these checksums. A text CAPTCHA is more accessible to visually impaired users than their image-based alternatives like ReCAPTCHA. Using text is also more flexible if for example you need to present the challenge over a text-only channel like SMS or IRC. The problem with text CAPTCHAs is that they provide inherently more information than a distorted image. They are parseable, under the right conditions solveable. With the advent of contextual parsing tools such as Wolfram Alpha, such simple logic puzzles have become easier to solve programatically.