What does this tool do?
| Direct answer | Base64 Decode converts Base64 alphabet characters back into the original UTF-8 bytes. |
| Key fact | Invalid characters or wrong padding make a Base64 string undecodable — the decoder reports the error. |
| Processing | Runs locally in your browser; no data is sent to a server. |
How to use
- Paste a Base64 string into the input.
- Click Decode from Base64.
- Copy the decoded text.
Example
Input
SGVsbG8sIHdvcmxkIQ==
Output
Hello, world!
Who is this for?
This tool was built for people who need a fast answer in the browser — no install, no account, no data leaving the device.
Developers verifying file checksums, DevOps engineers generating secrets, and security students learning encoding basics — all without uploading data to a server.
Frequently asked questions
Can I decode a data URI?
Paste the part after the comma; the prefix (data:image/png;base64,) is metadata, not payload.
Why do I get garbled text?
The input may not be valid Base64 or may use a different encoding (e.g. Latin-1) than UTF-8.
Does it decode Base64URL (- and _)?
Standard Base64 is expected; Base64URL variants need -/_ converted to +/ first.