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Encoding tools

Base64 Decode

Decode Base64 into UTF-8 text. Tool input is processed locally, without uploading it.

Runs locally

Drop a Base64 file here, or choose Open file. Up to 50 MB. Files stay in your browser.

Local history
Send to

Input: up to 50 MB. Above 1 MB, choose an action to start. Output: up to 75 MB. Large documents show a read-only preview; Download keeps the full result.

Guide

Recover readable text from a Base64 string. This tool interprets the decoded bytes as text and reports an error if the input is malformed or the bytes cannot be read as supported text.

  1. Add your text

    Paste into Input, try Example text or Example Unicode, or use Open file. You can also drop a UTF-8 text file.

  2. Decode the text

    Up to 1 MB updates automatically. For larger input, choose Decode to start and Cancel to stop.

  3. Check the result

    Output must be valid UTF-8 text. An error may mean the source is binary data or uses a different alphabet.

  4. Keep or share it

    Download keeps the full result, even when only a preview is shown. Copy supports up to 2 MB. Share input is available for small input.

On mobile, choose Output to read the result. Clear removes both fields.

Decoding

  • The result must be valid UTF-8 (Unicode Transformation Format, 8-bit) text. This tool does not export arbitrary binary files.
Shortcuts
  • Ctrl / Cmd + Enter — Run selected action
  • Ctrl / Cmd + Shift + C — Copy output
  • Ctrl / Cmd + S — Download output
  • ? — Show shortcuts outside text fields

Shortcuts work while focus is in the workspace. Copy and download need valid output.

Common questions
How do large files work?
Input can be up to 50 MB and output up to 75 MB. Large documents show a read-only preview. Processing has a five-second limit; try a smaller file if it times out.
Is Base64 encryption?
No. It is a reversible representation of bytes, with no password or secret key.
Does it support emoji and Danish letters?
Yes. Text uses UTF-8, including emoji and characters such as æ, ø and å. Invalid UTF-8 bytes are rejected.
Can I decode an image or URL-safe token?
This preview supports standard Base64 that contains UTF-8 text. Binary images, data-URI prefixes and URL-safe alphabets are not supported.
Is my text uploaded?
No. Processing and file reading happen locally in this browser. Only inputs you explicitly save in Local history are kept between visits.
What does Share input include?
The link contains your input. Nothing is uploaded by this tool, but anyone you give the link to can read it. Do not share secrets.

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Only your rating and optional feedback are sent. Your tool input and output are never included.