Cookie attribute

Meaning

A cookie attribute is an option written after the first semicolon of a Set-Cookie header, such as Path, Max-Age, Secure or SameSite. Attributes control a cookie's scope, lifetime and protection, but they are used only by the browser; they are never sent back to the server. Most take a value, like Path=/ or Max-Age=3600, while Secure, HttpOnly and Partitioned are bare words. Setting them deliberately on every cookie avoids relying on browser defaults, which differ for scope and for SameSite. See also: Domain, Path, Secure, SameSite, the guide "Domain, Path, Expires and Max-Age Explained".