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Base64 encoder / decoder

Encode Unicode text or decode Base64 without uploading it.

Base64 is an encoding, not encryption. Text input and decoded output use UTF-8.
Your input stays on this device. Only the utility name is counted for usage; the contents are never sent to our server.

How to use this tool

Turn text into Base64 for a text-based payload, or inspect an encoded value while debugging. Unicode characters are converted to UTF-8 bytes before encoding.

  1. Choose Encode text or Decode Base64 from the transformation menu.
  2. Paste your text or open a text file, then select Run utility.
  3. Review the output before copying or downloading it. Switch modes to reverse the conversion.

A small example

Encode text

Input

Hello

Output

SGVsbG8=

What to check before using the result

  • Base64 does not conceal data. Anyone with the encoded string can decode it.
  • This tool handles UTF-8 text, not arbitrary binary files or image previews. Invalid UTF-8 is rejected.
  • The standalone decoder accepts the standard Base64 alphabet. For Base64url segments in a token, use the JWT decoder. Inputs are limited to 1 MB.

Base64 format reference: RFC 4648

Continue your task

  • JWT decoder — Inspect the header and claims of a three-part token.
  • URL tools — Percent-encode text for a URL instead of using Base64.