Betafish.js

Betafish.js brings a strong chess artificial intelligence to your browser, letting you play matches against a capable opponent instantly. The interactive board supports standard chess rules and includes practical game controls for resetting, undoing moves, and flipping the board orientation.

Highlights

• Adjustable AI thinking time with four preset difficulty levels
• FEN notation support for analyzing and replaying positions
• Clean, web-based interface requiring no installation or downloads
• Open-source code available for review and contribution
• Runs entirely in the browser with no account or signup needed

Whether you're learning the fundamentals or looking to sharpen your tactics, Betafish.js offers a free, accessible way to improve your chess game. The flexible thinking-time settings mean you can calibrate matches to your skill level, making it suitable for beginners exploring strategy and experienced players seeking a quick sparring partner.