Lightweight, modern open-source CAPTCHA alternative designed using SHA-256 proof-of-work.



Synthient is described as 'Offers cutting edge bot and fraud protection while also giving you deep insights into your visitors. Track repeat visitors, device details, and the potential risk to your platform' and is an website. There are more than 10 alternatives to Synthient, not only websites but also apps for a variety of platforms, including SaaS, Self-Hosted, Docker and Go (Programming Language) apps. The best Synthient alternative is Cap Captcha, which is both free and Open Source. Other great sites and apps similar to Synthient are Anubis, hCaptcha, mCaptcha and IronWall.
Lightweight, modern open-source CAPTCHA alternative designed using SHA-256 proof-of-work.



Applies sha256 proof-of-work challenges to incoming HTTP requests, targeting AI crawlers, bots that ignore robots.txt, and automated scrapers, protecting server resources and preventing unwanted search engine indexing for privacy-focused sites.

hCaptcha is designed to solve the most labor intensive problem in machine learning: labeling massive amounts of data in a timely, affordable, and reliable way.



Anti-Fraud Solutions and top-tier IP Intelligence including Bot Detection, Chargeback Prevention, Click Fraud Monitoring, User Reputation Scoring, Transaction Scoring, and Email Validation.


DataDome is the only bot protection solution delivered as-a-service. Unlike competing products, it requires no architecture changes or DNS rerouting, and will never be a single point of failure.


SaaS software with APIs that allows you to get to understand your users and prevent unwanted behavior. Block scraping, adblocks, bots, VPN users and enable building analytics tools with our APIs.



OverpoweredJS is a browser fingerprinting API designed to identify and track browser instances. It helps website operators distinguish unique users, detect potential bots and enhance website security. Supports all modern browsers, including Chromium-based browsers (Google...
Fraud detection and prevention using browser fingerprinting with 99.5% accuracy. Stops account sharing, payment processing fraud and gaming.

Trueguard identifies suspicious and fake emails at signup. So you can focus on onboarding real users. Detect email quality and checking against our domain database. Analyse the user's IP address to determine if they originate from suspicious sources like a VPN or proxy.