Base64 Encoder / Decoder
Type or paste text below to automatically encode it to Base64. Switch to "Decode" to convert a Base64 string back to text. Need to format JSON instead? Try the JSON Formatter. For converting query parameters, check out the URL Encoder/Decoder.
🔒 Runs in your browser · Your data is never sent to a server
Notes
- Base64 is not encryption. Anyone can decode it, so it cannot protect passwords or other secrets.
- Text is handled as UTF-8 bytes, so Japanese characters and emoji work. Decoding Base64 that was created from another encoding (such as Shift_JIS) may fail with an error.
- Base64 output is about 1.33 times (4/3) larger than the original data.
Glossary
Base64
An encoding scheme that converts binary data into a string using only letters, digits, and a few symbols (A-Z, a-z, 0-9, +, /, =). Commonly used to embed binary data, such as images, in text-only formats like email or JSON.
Encode / Decode
Encoding converts data into another format; decoding reverses that conversion. Base64 encoding is not encryption — anyone can decode it back to the original data, so it does not protect sensitive information.
FAQ
Is Base64 encryption? Can it hide sensitive data?
No. Base64 is an encoding, not encryption. Anyone can decode it instantly, so it must not be used to protect passwords or other secrets.
Does it work with non-ASCII text such as Japanese or emoji?
Yes. Text is treated as UTF-8 bytes before encoding, so multibyte characters like Japanese and emoji are encoded and decoded correctly.
Why does decoding show an error?
The input is not valid Base64, or the decoded bytes are not valid UTF-8 text. Common causes are stray characters in the string, Base64URL input (containing - or _), a truncated copy, or data that is not valid UTF-8 text (such as Shift_JIS text or binary files like images). Check the original string.
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