Free SSL certificate checker: Check any SSL certificate
See whether a site’s certificate is valid, when it expires, who issued it, which names it covers and the full chain, checked from Stockholm.
Checked from Stockholm, Sweden · Free, no sign-up
- Try
Questions
How long is an SSL certificate valid?
Public certificates issued since March 15, 2026 are valid for at most 200 days, and the limit keeps falling: 100 days from March 2027 and 47 days from March 2029. Free certificates from Let’s Encrypt last 90 days and are renewed automatically, when the renewal works.
Why does a browser say the certificate isn’t trusted?
Usually one of four reasons: it has expired, it was issued for a different name, it’s self-signed, or the server doesn’t send the intermediate certificate that links it to a trusted authority. The result above names which one.
What is the certificate chain?
The server’s certificate is signed by an intermediate authority, which is signed by a root that browsers trust. The server must send its own certificate and the intermediates; the root is already in the browser.
How do I get warned before a certificate expires?
A website monitor on Uptimecheck reads the certificate on every check and reminds you 30, 14, 7 and 1 days before it expires, and on the day itself.
Let Uptimecheck keep watching
This free tool answers one question at a time. In Uptimecheck, the same work runs on its own and alerts you when something needs attention.
More free tools
All tools- Is it down? Check whether a website answers, how fast, and when its certificate expires. Open tool
- Domain expiry checker Look up a domain’s expiry date, registrar and age from the registry’s own records (RDAP, or WHOIS where there is none). Open tool
- DNS lookup Ask for any record type and see every answer with its TTL, straight from a resolver, without a cache in between. Open tool
Downtime is obsolete.
Set up your first monitor in under a minute, or look around the live demo first.
14-day free trial · Then free on 5 monitors · No credit card