Quickly find unused CIDR blocks in your AWS VPC

Finding new CIDR blocks in a VPC can get increasingly time consuming as you grow. I found a nice little tool which will quickly output to STDOUT the available ranges. You can find that here.

You can install it with: pip install aws-cidr-finder

Run with: aws-cidr-finder --profile aws-profile-name

Output looks like this:

CIDR               IP Count
---------------  ----------
172.31.96.0/19         8192
172.31.128.0/17       32768
Total                 40960
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