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K-ToolsBrowser utility

Free Base64 Encode/Decode Tool (UTF-8 + Data URLs)

Encode or decode Base64 strings in your browser, including UTF-8 text and full data URLs, with optional byte downloads.

Privacy shape
No account
Runs in browser
Copy output fast
Text / binary input
Output
Enter text to encode.
Supports plain Base64 and full data:*;base64, input.

Base64 decoding help

If a pasted value does not decode cleanly, these guides cover the two most common failure modes: invalid characters and full data URL prefixes.

Fix Base64 invalid character errorsRepair browser InvalidCharacterError, Base64URL characters, missing padding, data URL prefixes, and whitespace.Decode Base64 data URLs safelyIdentify the MIME type, strip the data:*;base64, prefix, and download binary output without corruption.

Base64 to UTF-8 FAQ

How do I decode Base64 to UTF-8 text?

Choose Decode, paste the Base64 value, then copy the UTF-8 text output. Full data:*;base64, URLs work too.

Can I decode a Base64 data URL?

Yes. In Decode mode, paste the complete data URL. The tool removes its prefix, decodes the bytes, and offers a byte download when appropriate.

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