AscendLab
Tool guide

Base64 Encoder & Decoder Guide

Reference for encoding and decoding Base64 text, handling UTF-8, padding, Base64URL differences, and token debugging limits.

Quick answer

Use the Base64 Encoder & Decoder to encode UTF-8 text into Base64 or decode Base64 back into readable text.

What this tool does

The tool is useful for inspecting API samples, token fragments, encoded JSON snippets, and transport-safe text values. Base64 is encoding, not encryption.

Supported input

  • Plain UTF-8 text for encoding
  • Base64 text for decoding
  • Common padding forms
  • Copy-ready encoded or decoded output

Data handling and processing behavior

Processing is handled in the browser for this tool based on the current public implementation. Avoid entering sensitive credentials or tokens unless you have reviewed the implementation and your own data handling requirements.

Step-by-step use

  1. Choose encode or decode
  2. Paste the text value
  3. Review validation messages
  4. Copy the output
  5. Format decoded JSON separately when needed

Common errors

Treating Base64 as encryption. Encoded text can be decoded by anyone with the value.

Mixing Base64 and Base64URL. Token segments often use URL-safe characters and padding rules.

Ignoring UTF-8. Non-Latin characters need consistent character encoding.

Limits

The tool does not decrypt content, verify JWT signatures, or decide whether a token is trusted.

Next steps

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