Domain Expiry Checker
Look up a domain’s expiry date, registrar, status and name servers via RDAP.
SSL Certificate Expiry Checker
Enter a hostname to see who issued its certificate, when it expires and which names it covers. An expired certificate breaks browsers, APIs and webhooks at the same time.
- Free
- No sign-up
- Checked from our server
Certificate
Hostnames it covers
How to use the SSL Certificate Checker
- Enter a hostname such as example.com: there’s no need for https://.
- Click Check certificate.
- Review the expiry date, days remaining and covered names.
- Set up expiry alerts so a renewal never slips.
Never miss an expiry again
SensaCat watches SSL certificates, domain registrations and credentials, and reminds your team well before anything expires.
Frequently asked questions
Browsers show a full-page security warning, and API clients, mobile apps and webhook senders refuse to connect. For most sites that means an outage until the certificate is renewed.
Common causes are a renewal cron job or timer that stopped running, an HTTP challenge blocked by a redirect or firewall, DNS changes, or a server that renewed the certificate file but was never reloaded. Monitor both the renewal job and the live certificate.
It reports the certificate the server presents for the hostname. It doesn’t validate the chain, so use it alongside a browser or a dedicated TLS test when you’re debugging trust errors.
Port 443, using the hostname you enter for SNI.
Related tools
HTTP Headers Checker
Follow a URL’s redirects, list its response headers and grade its security headers.
DNS Lookup
Query A, AAAA, CNAME, MX, TXT, NS, CAA and SOA records over DNS-over-HTTPS.