Cookie Decoder

Decode a Set-Cookie or Cookie header into name, value and every attribute, with Max-Age and Expires resolved to an exact date, and flags a missing Secure or HttpOnly, a SameSite=None without Secure, and a Domain wide enough to leak to subdomains.

SecurityCookiesSet-CookieSamesiteHeaders
Cookie Decoder screenshot

Paste a Set-Cookie or Cookie header and get the name, the value and every attribute decoded, with Max-Age and Expires resolved to an exact date and a plain duration. Flags a missing Secure or HttpOnly, a SameSite=None that modern browsers reject outright, and a Domain wide enough to leak the cookie to subdomains. ATTRIBUTES EXPIRY FLAGS

Name and value
Attributes
Lifetime
Security flags

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