Check if my SSL Certificate is SHA1 or SHA2

Question

Use the Linux Command Line

Use the command line, as described in this related question: How do I check if my SSL Certificate is SHA1 or SHA2 on the commandline.

Here’s the command. Replace www.yoursite.com:443 to fit your needs. Default SSL port is 443:

openssl s_client -connect www.yoursite.com:443 < /dev/null 2>/dev/null \
    | openssl x509 -text -in /dev/stdin | grep "Signature Algorithm"

This should return something like this for the sha1:

Signature Algorithm: sha1WithRSAEncryption

or this for the newer version:

Signature Algorithm: sha256WithRSAEncryption

The article Why Google is Hurrying the Web to Kill SHA-1 describes exactly what you would expect and has a pretty graphic, too.