Is Basic Auth encryption? Is it safe to use?

No — Base64 is a reversible encoding, not encryption. Anyone who sees the header can decode the username and password instantly, with no key required. Basic Auth is only safe over HTTPS, where the transport layer (not the header itself) protects it in transit; for anything sensitive, prefer a real auth scheme such as OAuth or a signed token.

Why split the decoded value on the first colon only?

A username in HTTP Basic Auth cannot contain a colon, but a password can. Splitting on the first ':' and keeping everything after it as the password is the only split that can't cut a password in half.

What does the "Basic " prefix mean?

It names the authentication scheme in the HTTP Authorization header — Authorization: . "Basic" tells the server to expect Base64-encoded user:pass credentials, as opposed to "Bearer" (a token) or other schemes.

Basic Auth Header Encoder / Decoder

How it works

A Basic Auth header is Basic followed by the Base64 encoding of username:password. Encoding here joins your username and password with a colon and Base64-encodes the result with full Unicode support; decoding reverses that, splitting on the first colon so a password containing one is preserved intact.

Basic Auth Header Encoder / Decoder

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