Base64 Decode
Paste a Base64 string to decode it back into readable text. Handles UTF-8 and emoji correctly, accepts base64url, and never uploads your data.
How to decode Base64
- Paste your Base64 or base64url string into the box.
- Read the decoded text in the output area as you type.
- Copy the result or download it as a text file.
Examples
Decode a greeting
aGVsbG8=
hello
Frequently asked questions
How does Base64 decoding work?
Base64 packs three bytes into four text characters from a 64-symbol alphabet. Decoding reverses that, rebuilding the original bytes and reading them as UTF-8 text.
What if decoding fails?
If the input has characters outside the Base64 alphabet or an invalid length, the tool shows an error. Check for stray characters and that the string was encoded as Base64.
Does it support base64url?
Yes. The base64url variant uses '-' and '_' in place of '+' and '/' and often drops padding. This tool converts it back and re-pads automatically before decoding.
Is Base64 secure or encrypted?
No. Base64 is an encoding, not encryption. Anyone can decode it, so never treat a Base64 string as a way to hide passwords or secrets.
Does it handle emoji and accented characters?
Yes. Multi-byte UTF-8 characters such as accents and emoji decode correctly because the bytes are read with a proper UTF-8 decoder.
Is my data private?
Yes. Decoding runs entirely in your browser and nothing is sent to a server.
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