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Base64 Encoder and Decoder

The Base64 tool converts text to Base64 and back. It handles the full Unicode range correctly, supports the URL-safe alphabet used in JWTs and query strings, and tolerates missing padding when decoding.

Options
Input 0 characters
Result

Your result will appear here.

Not sure where to start? Use Load example.

Results update automatically and are calculated on your device. Nothing you type is sent to a server.

Runs in your browser. Processing happens entirely in your browser. Nothing you enter is sent to Delimiter.live.

How to use the Base64 Encoder and Decoder

  1. Choose whether you are encoding or decoding.
  2. Paste your text or your Base64 string.
  3. Turn on the URL-safe option if the value belongs in a URL, a JWT or a filename.
  4. Copy the result.

Example

Input
Hello, world
Output
SGVsbG8sIHdvcmxk

Common use cases

  • Embedding a small image or font in a data URI.
  • Decoding a Base64 value found in a configuration file or an API response.
  • Encoding credentials for an HTTP Basic Authorization header.
  • Reading the payload of a JWT, which uses the URL-safe alphabet.

Limitations and things to watch for

  • Base64 is an encoding, not encryption. Anyone can decode it instantly, so it provides no confidentiality whatsoever.
  • Encoding increases size by roughly a third, which is the cost of representing binary data in text.
  • Text is encoded as UTF-8 before conversion, so non-ASCII characters round-trip correctly — something naive implementations often get wrong.
  • Decoding accepts both alphabets and tolerates missing padding, because many systems strip it.

Frequently asked questions

Is Base64 encryption?
No. It is a reversible encoding designed to carry binary data through text-only channels. Anyone can decode it in a second, so never use it to protect anything.
What is URL-safe Base64?
A variant that uses - and _ instead of + and /, because those two characters have special meaning in URLs. JWTs use it, and padding is usually stripped.
Why does my decoded text look wrong?
Usually because the original data was binary rather than text, or because it was encoded with a different character encoding. This tool decodes as UTF-8, which is correct for almost all modern data.
Does it work with emoji and accented characters?
Yes. The text is converted to UTF-8 bytes before encoding, so any Unicode character round-trips correctly.

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