Encode and decode Base64URL online
Encode and decode Base64URL (URL-safe variant used in JWT), in your browser.
Base64URL replaces + with -, / with _ and drops the “=” padding (RFC 4648 §5).
🔒 100% client-side — no data sent
Encode or decode text to Base64URL, the URL-safe variant used notably in JWTs. Everything runs 100% in your browser, so your tokens and sensitive data are never sent online. Unlike standard Base64, this version replaces characters that break in URLs.
What is it for?
- ▸ Decode a JWT payload to inspect its contents
- ▸ Encode a value to pass safely inside a URL
- ▸ Generate a URL-safe identifier from binary data
- ▸ Debug an OAuth token or a Base64URL-encoded signature
FAQ
What is the difference between Base64 and Base64URL?
Base64URL replaces the + and / characters with - and _, and usually drops the = padding, so it can be used in a URL without escaping. It's the variant used by JWTs and many web tokens.
How do I decode a JWT?
A JWT is made of three dot-separated parts, each Base64URL-encoded. Paste the header or payload part into the tool to decode it and read the corresponding JSON.
Is decoding a JWT safe with this tool?
Yes, because everything happens locally in your browser and no token is sent to a server. Your data stays private, which is essential when handling tokens.