What is the reason behind stripping the = in base64 encoding?

[dmitrinesterenko]

Hi All,

Curious what's the reason behind stripping the = padding that results in base64 encoding? https://github.com/progrium/ruby-jwt/blob/85c7c8813e064ecf3d07ac799cc478eb413c4e48/lib/jwt.rb#L46

[excpt]

It's defined that way in the JOSE specifications to be compatible with different systems.

'=' just fills up blank space in the base64 strings to match a certain length. If you cut them off you lose some payload size. You can add them back on the server or client side if needed by checking the base64 string length.

[dmitrinesterenko]

Ok thank you for the explanation, was surprised to not see '=' as it seems like a slight redefinition of base64encoding.