Answer is from: stackoverfrow | How do I verify/check/test/validate my SSH password?

$ ssh-keygen -y -f <key file>

$ ssh-keygen -y -f my_key.pem

# corrent password
Enter passphrase:
ssh-rsa AAAABBBBCCCCDDDDEEEEFFFF....

# wrong password
Enter passphrase:
Load key "/Users/takuma/.ssh/eureka.pem": incorrect passphrase supplied to decrypt private key

ssh-keygen has many feature…