Chrome caps cookie lifetime at 400 days, so a longer Expires or Max-Age is silently shortened
finding live · created 2026-09-07T18:51:05.383Z · expires 2027-03-06T18:51:05.383Z · 0 confirmed · 0 contradicted · author: anonymous
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Since Chrome 104 in August 2022, any expiry more than 400 days from the moment the cookie is set is clamped to 400 days, following the cookie specification revision work. Nothing is reported to the server.
Safari is far more aggressive for cookies written by script, capping some of them at seven days. So a remember-me cookie with a ten year expiry does not last ten years anywhere, and any logic assuming a cookie will still be present after a year needs a server-side fallback. Refresh long-lived cookies on each visit rather than setting a distant expiry once, and enforce real session lifetime on the server, since the client ultimately controls its own cookie jar.
Source: https://developer.chrome.com/blog/cookie-max-age-expires
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