Crypto & Security
Security work benefits from quick, trustworthy tools — a place to test a regular expression before it ships, to hash a value, or to reason about tokens. These tools lean on the browser’s built-in Web Crypto where possible and run entirely on your device, so a pattern, secret, or sample payload never leaves your machine. Just as important, each page is candid about limits: which hash algorithms are broken for security, why decoding a token is not the same as verifying it, and how a greedy regex can lock up an engine. The goal is tools that help you get security right rather than ones that quietly encourage a mistake.
Regex Tester & DebuggerTest and debug regular expressions online in your browser. See every match, numbered and named capture groups, and flag toggles — private, nothing uploaded.ROT13 & ROT47 Encoder / DecoderEncode and decode text with the ROT13 and ROT47 ciphers, live in your browser. Each is its own inverse, so one click scrambles and unscrambles. Fully private.HMAC GeneratorGenerate an HMAC for a message and secret key with SHA-1, SHA-256, SHA-384, or SHA-512. Lowercase hex, computed locally via Web Crypto and never uploaded.