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crt.sh vs Cert Spotter: catalog facts
crt.sh	Cert Spotter
Free Free to use.	Paid Paid monitoring service with a 30-day free trial.
Web	Web
Search by domain, organization or fingerprint Shows certificates from public CT logs	Alerts on any newly issued certificate for your domains via Certificate Transparency logs Catches expired, revoked and misinstalled certificates
Minimal interface aimed at technical users Only covers certificates that were logged	Paid after the 30-day trial Hosted service only
Web application	Web application, Hosted service
Closed source	Closed source
License not stated	License not stated
No account needed	Account needed
Needs internet	Needs internet
Official website Full listing and sources Checked September 23, 2026	Official website Full listing and sources Checked September 23, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.