Paste your JSON, get it nicely formatted or minified and see any errors. Your data never leaves this computer.
Only the contents of the JWT are read. The signature is not verified, so this tool does not prove that a token is genuine.
Enter Unix seconds or milliseconds, ISO 8601, or a date like "2026-09-30 14:30".
Type text or choose a file. SHA-1, SHA-256, SHA-384 and SHA-512 are computed. The file never leaves your computer.
An error message is shown, with the line and column of the problem when available. The result box stays empty.
JavaScript cannot store integers longer than 16 digits exactly. If we see such a number we add a warning next to the result.
No. Everything happens in your browser and your JSON is never uploaded.