Hash Generator
Hash text or a file with MD5, SHA-1, SHA-256 and SHA-512. SHA family uses the Web Crypto API; MD5 runs locally too.
MD5, SHA-1, SHA-256, SHA-512
Utilities
Security tools
A small, growing set of utilities I reach for often. Pick one — they all run entirely in your browser.
Encoder / Decoder
Encode and decode Base64, URL percent-encoding, HTML entities and hexadecimal, both directions.
Base64 · URL · HTML · Hex
JWT Decoder
Decode a JSON Web Token to inspect its header and claims. Decode only — signatures are never verified and nothing is stored.
Decode header & payload
Password Tools
Generate strong random passwords with the Web Crypto API and estimate strength (entropy and crack-time) as you type.
Generate & check strength
CIDR / Subnet Calculator
Work out network and broadcast addresses, usable host range, mask and host count from any IPv4 CIDR.
IPv4 network math
Regex Tester
Test JavaScript regular expressions against sample text with live match highlighting and capture groups.
Test & highlight matches