CIDR IPv4 Subnet Cheat Sheet

For number of addresses, I always used this formula:
32 – (cidr) = X
then 2^x = number of addresses
To get the number of hosts, subtract with 2 (network and subnet mask)

Example: (to get # of addresses and hosts of /24)
32 – 24 = 8
2^8 = 256 (total number of addresses)
256 -2 = 254 (total number of hosts)

CIDRAddressesNetmaskWildcard
/321255.255.255.2550.0.0.0
/312255.255.255.2540.0.0.1
/304255.255.255.2520.0.0.3
/298255.255.255.2480.0.0.7
/2816255.255.255.2400.0.0.15
/2732255.255.255.2240.0.0.31
/2664255.255.255.1920.0.0.63
/25128255.255.255.1280.0.0.127
/24256255.255.255.00.0.0.255
/23512255.255.254.00.0.1.255
/221,024255.255.252.00.0.3.255
/212,048255.255.248.00.0.7.255
/204,096255.255.240.00.0.15.255
/198,192255.255.224.00.0.31.255
/1816,384255.255.192.00.0.63.255
/1732,768255.255.128.00.0.127.255
/1665,536255.255.0.00.0.255.255
/15131,072255.254.0.00.1.255.255
/14262,144255.252.0.00.3.255.255
/13524,288255.248.0.00.7.255.255
/121,048,576255.240.0.00.15.255.255
/112,097,152255.224.0.00.31.255.255
/104,194,304255.192.0.00.63.255.255
/98,388,608255.128.0.00.127.255.255
/816,777,216255.0.0.00.255.255.255
/733,554,432254.0.0.01.255.255.255
/667,108,864252.0.0.03.255.255.255
/5134,217,728248.0.0.07.255.255.255
/4268,435,456240.0.0.015.255.255.255
/3536,870,912224.0.0.031.255.255.255
/21,073,741,824192.0.0.063.255.255.255
/12,147,483,648128.0.0.0127.255.255.255
/04,294,967,2960.0.0.0255.255.255.255

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