Utilities for developers and technical users.
Format, minify, and validate JSON instantly in your browser, with clear line-and-column error messages when something is invalid.
Convert a Unix timestamp to a human-readable date, or a date to a Unix timestamp, in seconds or milliseconds, with UTC, local time, and relative time shown together.
Generate one or many random v4 UUIDs (GUIDs) instantly in your browser, using the same cryptographically secure randomness browsers use for everything else.
Test a regular expression against sample text and see every match, capture group, and index update live as you type, with clear error messages for invalid patterns.
Encode text to Base64 or decode Base64 back to text instantly in your browser, with correct handling of Unicode characters and emoji.
Decode a JSON Web Token's header and payload instantly, and check whether it has expired — entirely in your browser, without verifying or transmitting the signature.
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