Is Stack Overflow SSL down right now?
This page answers whether Stack Overflow SSL is down by checking the certificate stackoverflow.com serves, live and from outside, rechecked every hour. Most "is it down" pages ping the homepage; a broken or expired certificate is a different failure, and it is the one this page watches.
Last checked 2026-09-20 07:44 UTC. CertPost is not affiliated with Stack Overflow.
Common questions
Is Stack Overflow SSL down right now?
No. At the last check the certificate stackoverflow.com serves was valid, and it expires on 2026-11-13. Stack Overflow SSL is up.
How does this page know if Stack Overflow SSL is down?
A CertPost probe opens a real TLS connection to stackoverflow.com on port 443, the same way a browser does, and reads the certificate. The result is cached and rechecked every hour, so this reflects the healthy state seen at the last check, not a guess.
Is this the same as Stack Overflow being down?
Not always. A site can be reachable while its certificate is broken, or down for reasons unrelated to SSL. This page measures only the certificate stackoverflow.com serves. For the full certificate detail, see the Stack Overflow certificate status page.
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