What is Base64?
Base64 is an encoding that turns binary data into ASCII text using 64 printable
characters (A–Z, a–z, 0–9, plus + and /). It's used
to safely embed binary content (images, signatures, file uploads) in places
that only accept plain text — like JSON payloads, HTML data: URIs,
email attachments (MIME), and JWT tokens.
How to use this tool
- Pick Encode to turn text into Base64, or Decode to go the other way.
- Paste your input. The output updates as you type — no submit button needed.
- Click Copy to grab the result.
Is my data private?
Yes. Encoding and decoding happen entirely in your browser using the built-in
btoa / atob primitives with a UTF-8 layer for
non-ASCII text. Nothing is sent to a server. You can verify by opening DevTools
→ Network tab.
Common use cases
- Decoding the payload of a JWT (the middle segment is Base64-URL encoded).
- Embedding a small image as a
data:URI in CSS or HTML. - Inspecting API responses where binary blobs are encoded as Base64.
- Encoding HTTP Basic Auth credentials (
username:password).