VouchSafe - The Easy, Effective Replacement for CAPTCHAs.
VouchSafe is an easy, effective replacement for traditional CAPTCHAs. Like CAPTCHAs, VouchSafe is a simple test designed to separate human users from bots, to help prevent spam and some kinds of online fraud. VouchSafe is the first image-based Human Interactive Proof that uses an Adaptive AI to generate challenges based on the way humans think. As more people make use of VouchSafe, the AI that drives it learns from their responses and adapts to the choices they make.
To complete a VouchSafe challenge, users simply use their mouse to draw a line to match two objects that are related, or to circle an object that doesn't belong.
VouchSafe also provides keyboard accessible audio challenges for the visually or motor impaired.
VouchSafe is completely free. To get VouchSafe for your website, simply click on the "Get Vouchsafe" button above.