SSL Server Test
Qualys SSL Labs provides the best free tool to test and grade your SSL/TLS configuration.
Whenever you set up SSL/TLS on a server, always validate your configuration with Qualys SSL Labs.
It grades your certificate setup, checks for vulnerabilities (BEAST, POODLE, Heartbleed), validates your certificate chain, and tests protocol support. Aim for an A+ rating.
Free, fast, and the industry standard for SSL testing.