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Q&A > CGI programming > How can I delete a cookie? - Answer contributed by Ovid

See How can I maintain a session cookie for more information.

If you don't set an expiration date on a cookie that you've created, it will be deleted when the browser is closed.

If the user wants to delete a cookie created in a previous session, you can set the expiration date of the cookie in the past (or possibly set it to "", I haven't tried this).

If you'd like to learn more, you can read Netscape's Preliminary Specification for cookies.