Alternatives to Decoder.link SSL Checker
An online SSL checker that validates a server's certificate installation, with SNI and STARTTLS support. The listings below can replace it for an important use case. Each note says what changes if you switch.
The original
Decoder.link SSL Checker
An online SSL checker that validates a server's certificate installation, with SNI and STARTTLS support.
Replacements
Listings that take over the same core job as Decoder.link SSL Checker.
SSL Shopper SSL Checker
An online checker that verifies a server's SSL certificate installation, chain, hostname and expiry.
SSL Shopper SSL Checker verifies chain, hostname and expiry with optional expiry reminders, but checks public hostnames only and results may be cached for a day.
DigiCert SSL Installation Checker
A DigiCert web tool that diagnoses TLS/SSL certificate installation problems on a server.
DigiCert SSL Installation Checker diagnoses installation and chain problems with guides for common errors, from a certificate vendor's site.
SSL Labs Server Test
A Qualys web service that analyses the TLS/SSL configuration of a public web server.
SSL Labs Server Test runs a full protocol, cipher and vulnerability audit with a letter grade, though a full test takes a while and covers public web servers.
ImmuniWeb SSL Security Test
A free online test of the SSL/TLS setup of a web or email server.
ImmuniWeb SSL Security Test covers web and email servers with compliance checks and PDF export, going beyond certificate installation to the full TLS setup.
CheckTLS
A web tool that tests whether a recipient's mail server accepts secure TLS connections for email.
CheckTLS focuses on mail server TLS, showing the full SMTP conversation, with advanced features behind a subscription.
testssl.sh
A free command-line tool that checks a server's TLS/SSL ciphers, protocols and cryptographic flaws.
testssl.sh is an open-source command-line script that tests any port and checks ciphers and flaws beyond certificate installation.
Similar software
Related functionality, not a direct replacement.
TrackSSL
A hosted service that monitors SSL/TLS certificates and sends alerts before they expire or change.
Cert Spotter
A hosted Certificate Transparency monitor that alerts on unauthorized, expiring and invalid SSL certificates for your domains.
CAA Test
A web tool that checks the DNS CAA records published for a domain.
CryptCheck
A web tool that checks the TLS configuration of HTTPS, SMTP and XMPP servers.
Hardenize
A web site configuration tester and monitoring service for network, certificate and security settings.
crt.sh
A free web search engine for certificates recorded in public Certificate Transparency logs.
