captcha
Privacy-first, GDPR-compliant Captcha that just works. Block bots, not people.
Protect your forms and APIs with CAPTCHA that doesn't get in the way of your users or your legal team.
Private Captcha is an independent, privacy-first, self-hostable Proof-of-Work CAPTCHA service made in EU.
the modern spam protection
mosparo is the modern spam protection system for your forms. mosparo will catch the spam messages before they get sent to your inbox. It is usable by everybody – except robots – and is open source and free to use.
Cap is a lightweight, modern open-source CAPTCHA alternative designed using SHA-256 proof-of-work.
mCaptcha is proof-of-work based captcha system that is privacy focused and fully automated. A no-nonsense CAPTCHA system with seamless UX.
mCaptcha is a privacy respecting, free CAPTCHA system with a kickass UX. Your users no longer have to interact with ridiculous image-based CAPTCHA system, wasting precious mental bandwidth. Instead, your computer will do the work for you, see for yourself!
Stop more bots. Start protecting user privacy. The #1 privacy-first CAPTCHA for web, mobile, and more.
Captcha solver extension for humans. Buster is a browser extension which helps you to solve difficult captchas by completing reCAPTCHA audio challenges using speech recognition. Challenges are solved by clicking on the extension button at the bottom of the reCAPTCHA widget.
A configurable captcha solution, focusing on accessibility & simplicity whilst maintaining security.
CAPTCHA is a way how to verify that web application user is human. Using of CAPTCHA is a need in many web applications. Today it is commonly used by types based on the recognition of alphanumeric characters. The problem is that these tests are becoming more and more complicated for people, but, on the other hand, they are becoming even easier for bots. Therefore, I decided to create a concept to be based on a completely different principle. The result of my endeavour was the 3D captcha technology.
CAPTCHA validation using math operations
MotionCAPTCHA is a jQuery CAPTCHA plugin, based on the HTML5 Canvas Harmony procedural drawing tool by Mr Doob and the $1 Unistroke Gesture Regonizer algorithm (and the more recent Protractor algorithm improvement), requiring users to sketch the shape they see in the canvas in order to submit a form.
To use custom template image I have to inherit image-based bot detector and override GetTemplateImage method. Within the method I am fetching an image from Google search results based on predefined search keyword. For example, I want to get images for the theme "Landscapes". I select keywords that match this theme: "forest", "mountains", "waterfall", "falls", "hills", "lake".
Confident CAPTCHA™ is an easy to use, clickable, picture CAPTCHA that stops spam and bots on websites by asking visitors to verify they are human by clicking on specific images.
Are you dead tired of all those lame captcha verifiers? Well,.. in a real 'eureka' moment we had the idea to create an alternative. 'Fartcha'. You hear a Fart and you just have to type down what you think you just heard. You can always use the spell fart feature. (Your fart entry needs to be matched for 60% to pass. (% can be changed))
Professional free CAPTCHA for your site Even if you are Google
Asirra is a human interactive proof that asks users to identify photos of cats and dogs. It's powered by over three million photos from our unique partnership with Petfinder.com. Protect your web site with Asirra � free!