Free developer tools and APIs. No signup, no tracking, no ads. Pay with Lightning if you want more.
Scan any website for security issues. SSL, headers, DNS, speed — get a letter grade A through F.
NEWCompare two JSON objects side by side. See additions, deletions, and changes highlighted.
NEWConvert USD to Bitcoin satoshis and back. Real-time BTC price.
Interactive tools: JSON formatter, Base64, URL encoder, hash generator, regex tester, and more.
Live pattern matching with capture groups and common pattern library.
NEWPaste a cron expression, get plain English + next 5 run times.
NEWDecode JSON Web Tokens instantly. See header, payload, expiration. Client-side only.
NEWHow long to crack your password? Entropy analysis, attack scenarios, improvement tips. 100% client-side.
NEWCheck if any website is down for everyone or just you. Response time, SSL status, HTTP headers.
NEWWhat do websites know about you? Browser fingerprint, IP, screen, fonts, WebRTC leaks. Eye-opening.
NEW · VIRALInstantly see your public IP address, location, ISP, and privacy exposure score. No tracking.
NEWSee every HTTP header your browser sends. User-Agent, cookies, referrer — with risk ratings.
NEW6 tests in 30 seconds: DNS leaks, IP exposure, browser fingerprint, WebRTC, headers, connection security. Get your privacy score.
HOT · NEWCheck if your VPN is leaking DNS queries to your ISP. Instant results with fix recommendations.
POPULARCurated list of free public APIs that need no API key. With curl examples.
30 REST endpoints: SSL, DNS, email, hash, UUID, QR, crypto, base64, JWT, cron, site-check, and more.
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