Base64 both ways
Encode text or a file as Base64, or decode Base64 back to text or bytes. Pick the standard or URL-safe alphabet and whether to pad; decoding reads either. When the decoded text is a JSON Web Token or JSON, the page says so and links the tool that reads it.
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How to use
Choose Encode or Decode. To encode a file, drop it on the box or press Open file: its bytes are encoded as they are, so an image or a PDF works too. When decoded bytes are not text, the page shows the first 512 of them in hex, names the file type when it knows the first bytes, and Download saves them all.