Base64 Decoder
Decode Base64 strings back to readable text.
How to use Base64 Decoder
- Paste the Base64 text into the box.
- The decoded text appears immediately.
- Click Copy to copy it. If the input is invalid, an error explains why.
About Base64 Decoder
The Base64 Decoder turns Base64 back into readable text. Use it to inspect data from APIs, email headers, tokens or config files.
It accepts both standard and URL-safe Base64, ignores spaces and line breaks, and works even when the = padding is missing. It decodes to text only. If the data is a binary file such as an image, the tool tells you it is not readable text. Everything runs in your browser and nothing is sent to a server.
Features
- Standard and URL-safe Base64
- Tolerates whitespace and missing padding
- Decodes UTF-8 text in any language
- Clear errors for invalid or binary data
Frequently asked questions
Why does it say the data is not readable text?
The Base64 is valid, but the decoded bytes are not UTF-8 text. That usually means the original data was a file, such as an image or a compressed archive.
Why does it say my Base64 is invalid?
Base64 uses only letters, numbers, +, / (or - and _), and = at the end. Other characters, or a string cut off partway, will be rejected.
Can I decode a JWT with this?
You can decode each dot-separated part of a JWT as URL-safe Base64 to read its contents. Decoding does not verify the signature.