Base64 decoder

Paste a Base64 string and recover the original file—PDF, image, Office document, zip, or plain text—with automatic format detection.

How it works

  1. Paste standard or URL-safe Base64 from logs or APIs.
  2. Tick URL-safe mode when the string uses - and _ instead of + and /.
  3. Decode bytes and sniff MIME type from file signatures.
  4. Download the rebuilt file with a sensible extension.

Important notes

  • ✓ Malformed Base64 cannot be recovered—check for line breaks.
  • ✓ Guessed extensions depend on decoded content, not filenames.
  • ✓ Only decode data you trust; downloads can contain anything.