Base64 Encoder/Decoder
Convert any text to Base64 or decode Base64 back to readable text, correctly handling Unicode characters via UTF-8 byte encoding — never the Latin1-only limitation of a plain btoa/atob call. Processed entirely in your browser.
The text is processed entirely on your device and is never sent to any server.
Result
The result will appear here
What this tool does
Encodes text to Base64 or decodes it back. Base64 represents data using characters that are safe to carry anywhere only plain text is allowed.
When to use it
- Inspecting a Base64-encoded token or header to read what it contains.
- Embedding data in a URL or a config file that accepts text only.
- Testing an integration that exchanges encoded data.
- Decoding part of an access token to understand its structure.
How to use it
- Choose the direction: encode or decode.
- Paste your text into the field.
- Copy the result.
A practical example
Input
A short piece of plain text, encoding.
Output
A Base64 string representing the same text, about a third longer because the encoding expands the data.
Limitations
- Base64 is an encoding, not encryption: anyone can decode it instantly with no key. Never use it to conceal anything sensitive.
- Encoding increases the size by roughly a third.
- Malformed or truncated encoded text decodes to nonsense.
- To turn an image into Base64, use the dedicated Image to Base64 tool.
Privacy and processing
The text is processed entirely on your device and is never sent to a server — which matters, because what gets decoded here is often an access token or an authentication header.
Technical notes
- Encoding and decoding use the browser's built-in functions, so the result matches what any standard tool produces.