Base64 Decode
Turn a Base64 string back into readable text.
Free No signup Runs in your browser — nothing uploaded
Result
What it does
Base64 Decode applies the encoding exactly as specified, including the edge cases that hand-rolled versions get wrong: Unicode beyond ASCII, padding, reserved characters, and the difference between encoding a whole URL and encoding one component of it.
When you need it
Embedding data somewhere that only accepts plain text — a query string, a header, a data URI, a config value — or reading back a string that arrived already encoded and needs to be legible.
Limits and caveats
Encoding is not encryption and offers no protection whatsoever: anyone can decode it in a second. Do not use it to hide credentials or anything else that matters. Everything happens in your browser, so the file never leaves your device.
How to use the Base64 Decode
- Paste your content, or load a file.
- The result appears as you type.
- Copy or download the output.
Frequently asked questions
- Why does it say invalid?
- Base64 only allows A-Z, a-z, 0-9, + and /. Stray characters break it.
- Do my files get uploaded?
- No. This tool runs entirely in your browser, so the file never leaves your device.