About the Base64 Decode
This tool decodes Base64 to text, interpreting the bytes as UTF-8 so that encoded accented characters and emoji come back intact. It accepts both alphabets: standard (+, /) and URL-safe (-, _), with or without padding, and it strips whitespace and newlines automatically, so MIME-wrapped input works too. A data:...;base64, prefix is recognised and removed.
If the decoded bytes are not valid UTF-8 text, for example because the Base64 held an image or a zip file, the tool tells you and offers the raw bytes for download rather than showing garbled characters. Invalid Base64, such as an odd length or a stray character, produces a clear message instead of a cryptic exception.
Everything runs in your browser, so decoding a token or a payload that contains personal data is safe. Use JWT Decoder for tokens, since it splits and decodes all three parts, and Base64 to Image for image data.
How to use
- Paste the Base64 string, in either alphabet.
- Read the decoded text on the right.
- If it is binary, use Download to save the bytes.
Common questions
- It says the input is not valid Base64. Why?
- Base64 uses only A-Z, a-z, 0-9 and two extra characters. A stray space in the middle, a missing character, or wrong padding triggers the message. This tool already ignores line breaks.
- The output looks like garbage. What happened?
- The data was probably a binary file, not text. Use the Download button to save it, or the Base64 to Image tool if it is a picture.
- Can it decode a JWT?
- It decodes one Base64 part. For a full token with header, payload and signature, use the JWT Decoder.