Alternatives to crt.sh

A free web search engine for certificates recorded in public Certificate Transparency logs. The listings below can replace it for an important use case. Each note says what changes if you switch.

  • crt.sh

    A free web search engine for certificates recorded in public Certificate Transparency logs.

    FreeProprietaryWeb

Replacements

Listings that take over the same core job as crt.sh.

  • Cert Spotter

    A hosted Certificate Transparency monitor that alerts on unauthorized, expiring and invalid SSL certificates for your domains.

    PaidProprietaryWeb

    Cert Spotter is a paid hosted service that watches Certificate Transparency logs and alerts you on new or broken certificates, instead of manual searches.

  • Hardenize

    A web site configuration tester and monitoring service for network, certificate and security settings.

    FreemiumProprietaryWeb

    Hardenize offers continuous certificate monitoring for organisations plus free public configuration reports, rather than a free log search.

Similar software

Related functionality, not a direct replacement.

  • CAA Test

    A web tool that checks the DNS CAA records published for a domain.

    FreeProprietaryWeb

  • SSL Labs Server Test

    A Qualys web service that analyses the TLS/SSL configuration of a public web server.

    FreeProprietaryWeb

  • TrackSSL

    A hosted service that monitors SSL/TLS certificates and sends alerts before they expire or change.

    FreemiumProprietaryWeb

  • DNSDumpster

    A web tool that discovers DNS records and hosts related to a domain for security research.

    FreeProprietaryWeb

  • SSL Shopper SSL Checker

    An online checker that verifies a server's SSL certificate installation, chain, hostname and expiry.

    FreeProprietaryWeb

  • Who.is

    A web lookup for WHOIS, RDAP, DNS records, nameservers and IP ownership of any domain.

    FreemiumProprietaryWeb