🔑 Basic Auth Header Generator
Generate and decode HTTP Basic Authorization headers locally in your browser.
Last updated: May 18, 2026 · By Λ
By Λ · Updated May 18, 2026 · ~3 min read
Why I needed this tool offline
I do a lot of API integration work and an alarming amount of it still uses HTTP Basic auth on internal endpoints. Most of the existing online Basic-auth tools want you to paste your username and password into a form on someone else's server, which is exactly what you should never do with real credentials. So I wrote this one for myself. The whole encode-and-decode flow is JavaScript running in your browser. The Network tab will confirm: no outbound request gets made for the credentials you type.
For testing endpoints with curl, Postman, or a script, the workflow is: paste username and password, copy the Authorization: Basic <token> line, paste into your client. The token is just username:password Base64-encoded, but doing it by hand with special characters in the password is the kind of thing that will eat an afternoon of debugging.
The decode side is for the other direction: you captured an Authorization header in a request log and want to know what credentials were used. Paste either the full header or the raw token, hit Decode, and you get the parsed pair back. Again, all of this is local. The page does not phone home with anything you paste.
How to Use This Tool
- Enter a username and password in the generator fields.
- Click Generate or use live updates while typing.
- Copy the Base64 token or the full Authorization header.
- Paste a header or token into the decode box when needed.
- Click Decode to view parsed username and password values.
Key Features
- Generates Basic auth token and full Authorization header.
- Handles Unicode credentials with UTF-8 encoding.
- Decodes full headers or raw Base64 tokens.
- Copy buttons for fast API testing workflows.
- Both directions, encode and decode, execute as in-page JavaScript, so the credentials you enter stay on this device.
Frequently Asked Questions
Is Basic auth secure?
Basic auth is only safe over HTTPS. Without TLS, credentials can be intercepted. Always use HTTPS in production.
Does Base64 encrypt credentials?
No. Base64 is an encoding format, not encryption. Anyone with the token can decode it back to plaintext username and password.
When should I use Bearer tokens instead?
Bearer tokens are common for modern OAuth and JWT flows. Basic auth is usually best for simple service integrations or legacy endpoints.
Does this tool store my credentials?
No. Input and output are processed in-page and not uploaded by this tool logic.