SecureKit — Security & Identity Tools
Generate cryptographically strong passwords and UUIDs, and inspect JWT tokens — all locally, powered by your browser’s built-in crypto.
100% client-side Free forever No sign-up
Runs 100% in your browser — nothing is ever uploaded.
All SecureKit tools
Password Generator Create cryptographically secure passwords with your rules — length, symbols, digits, upper/lowercase — plus a live strength meter. Generated on your device, never transmitted. UUID Generator Generate one or hundreds of RFC-4122 UUID v4 identifiers with formatting options. Uses your browser’s native crypto — instant and offline-capable. JWT Decoder Paste a JSON Web Token to inspect its header and payload, check expiry with readable timestamps, and verify structure — entirely on your device. JWT generator Build and sign test JWTs locally — secrets never leave your device. Unit Converter Length, weight, temperature, area, volume, speed. PX to EM Pixel values to em, rem and % from any base size. Keyboard Tester Press any key — see code, key and modifiers live. JSON Schema Generator Infer a complete JSON Schema from sample data. Sample Data Generator Fake but realistic rows for testing, JSON or CSV. Cookie Banner Generator GDPR banner snippet — HTML, CSS and JS in one copy. Pomodoro Timer Work/break cycles with notifications. SemVer Calculator Compare versions and test npm ranges.
Frequently asked questions
Is it safe to generate passwords in a browser?
Yes — we use the Web Crypto API (crypto.getRandomValues), the same cryptographically secure randomness source used by password managers. Generation happens on your device and nothing is transmitted or stored.
Do you see the JWT tokens I decode?
No. Decoding is pure client-side Base64 parsing — the token never leaves your browser. Still, avoid pasting production secrets anywhere as a general habit.
Are the UUIDs really unique?
UUID v4 has 122 random bits — the collision probability is so small it is negligible for any real-world system. We use the native crypto.randomUUID() implementation.