Checking a SSL certificate’s expiry date with Python

Before I found the --keep-until-expiring option in the Let’s Encrypt command line client, I was thinking I’d have to parse the cert, extract the expiry date, then check it against the current date before returning True or False.

Thankfully I found the much easier option, but I decided to post the code I wrote to read the date just in case I need something like it in the future.
from datetime import datetime
from OpenSSL import crypto as c
cert = c.load_certificate(c.FILETYPE_PEM, file(‘/etc/letsencrypt/live/<domain>/cert.pem’).read())


  1. #1 by Thomas on July 13, 2016 - 7:57 pm

    Thanks a lot ! 🙂

  2. #2 by Denis on July 28, 2017 - 5:47 am

    Thank you very much !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

  3. #3 by Luis on October 3, 2019 - 1:52 pm

    yep, this is exactly what i was looking for. thanks!

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