URL Codec

Validate, pretty-print or minify JSON with error line:col reporting

Convert Unix timestamps to dates, auto-detect seconds/milliseconds

Convert text to/from Base64, handles Unicode correctly, URL-safe mode

Online regex tester with group highlighting and match details

Batch generate UUID v4 unique IDs using cryptographic random

Convert between Chinese and Unicode escape sequences for config files

Decode JWT tokens to view header, payload, signature, and expiry

Convert text to/from hexadecimal UTF-8 byte representation