SSLMate Certificate Search API (Cert Spotter)
FreemiumLiveLast verified 29 Sept 2026
Lists publicly trusted SSL/TLS certificates issued for a domain, with issuer, expiry and revocation status.
Example request
curl -s 'https://api.certspotter.com/v1/issuances?domain=example.com&expand=dns_names' -H 'Authorization: Bearer $API_KEY'
Free tier, in plain English
A few keyless lookups an hour are allowed for testing. A free account raises that to 100 hostname queries an hour, with paid plans from $50/month.
Alternatives in Website Security
Mozilla http scannerScans a website's HTTP response headers (CSP, HSTS, etc.) and returns a security grade and score.FreeMozilla TLS ObservatoryScans a domain's TLS setup and X.509 certificate chain and grades it against Mozilla's guidelines.FreeSSL LabsRuns a deep SSL/TLS configuration test on any public HTTPS server and returns an A+ to F grade.Free
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