Diff two certificate files with certdiff

If you’ve ever had to handle certificates, it can sometimes – especially when renewing them – become confusing to know which certificate is which. Enter certdiff, a handy diff tool for certificates, by Mattias Geniar:

$ ./certdiff cronweekly.com/cert.pem sysca.st/cert.pem
subject= /CN=cronweekly.com                               |  subject= /CN=sysca.st
issuer= /C=US/O=Let's Encrypt/CN=Let's Encrypt Authority     issuer= /C=US/O=Let's Encrypt/CN=Let's Encrypt Authority
notBefore=Feb 15 08:48:00 2016 GMT                        |  notBefore=Feb 15 09:11:00 2016 GMT
notAfter=May 15 08:48:00 2016 GMT                         |  notAfter=May 15 09:11:00 2016 GMT

Differences are highlighted using the diff -y output (side-by-side diff), output with the | character in between indicates differences between the files.

certdiff (GitHub) →
certdiff (Introductory Blogpost) →

Published by Bramus!

Bramus is a frontend web developer from Belgium, working as a Chrome Developer Relations Engineer at Google. From the moment he discovered view-source at the age of 14 (way back in 1997), he fell in love with the web and has been tinkering with it ever since (more …)

Leave a comment

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.