Quick way to confirm whether the private key matches that of X509 certificate using Openssl

Typically, the modulus of the private and public keys should match and a hash of their values would make for easy comparison

https://kb.wisc.edu/middleware/page.php?id=4064

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$ openssl x509 -noout -modulus -in server.crt | openssl md5
$ openssl rsa -noout -modulus -in server.key | openssl md5
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