JWT token How to split claim and signature

Question

In JWT token authentication, it is mentioned the "." is used for splitting the 3 parts of token (header, claim, signature). But in-case if my signature or encoded claim contains the "." it would be difficult the exact content of 3 section. Anybosy came across this situation or what is the way to handle it?

I generated signature using HMACSHA256(encoded json claim), but I'm getting "." in middle of the signature data. when i concatenate all the 3 parts, i'm getting one extra "."

Answer 1

The three parts of the JWT token are all base64 encoded and therefore will never contain a dot character.

Even if your claim or signature contains that character, after base64 encoding that part the dot will no longer appear in the output.