IPv4 Subnets

I've gotten tired of doing binary math to calculate IPv4 subnets in my head, so I created the following two reference tables. The first table is small and can be used to easily slide horizontally to look up information for a subnet within an octet. Where as the second larger table can be used to slide vertically to look up information for any possible 32 bit subnet.

Bits
The number of bits in the netmask, counting from the left (MSB) to the right (LSB).
Netmask
The doted quad netmask in decimal notation.
Hexmask
The doted quad netmask in hexadecimal notation.
Wildcard
The wildcard is a Cisco nomenclature that is a binary inversion of the netmask.
Sub Networks
The number of sub networks for the given netmask.
Host IPs
The number of usable host IPs for the given netmask. - Remember that you loose two usable IPs to network and broadcast addresses.
Binary
The decimal value of the given bit.
Bits 0 1 2 3 4 5 6 7 8
Netmask 0 128 192 224 240 248 252 254 255
Hexmask 0 80 C0 E0 F0 F8 FC FE FF
Wildcard 255 127 63 31 15 7 3 1 0
Sub Networks 0 2 4 8 16 32 64 128 256
Host IPs 254 126 62 30 14 6 2 0 0
Binary 256 128 64 32 16 8 4 2 1

Bits Netmask Hexmask Wildcard Sub Networks Host IPs Binary
0 0.0.0.0 0.0.0.0 255.255.255.255 0 4,294,967,294 4,294,967,296
Bits Netmask Hexmask Wildcard Sub Networks Host IPs Binary
1 128.0.0.0 80.0.0.0 127.255.255.255 2 2,147,483,646 2,147,483,648
2 192.0.0.0 C0.0.0.0 63.255.255.255 4 1,073,741,822 1,073,741,824
3 224.0.0.0 E0.0.0.0 31.255.255.255 8 536,870,910 536,870,912
4 240.0.0.0 F0.0.0.0 15.255.255.255 16 268,435,454 268,435,456
5 248.0.0.0 F8.0.0.0 7.255.255.255 32 134,217,726 134,217,728
6 252.0.0.0 FC.0.0.0 3.255.255.255 64 67,108,862 67,108,864
7 254.0.0.0 FE.0.0.0 1.255.255.255 128 33,554,430 33,554,432
8 255.0.0.0 FF.0.0.0 0.255.255.255 256 16,777,214 16,777,216
Bits Netmask Hexmask Wildcard Sub Networks Host IPs Binary
9 255.128.0.0 FF.80.0.0 0.127.255.255 512 8,388,606 8,388,608
10 255.192.0.0 FF.C0.0.0 0.63.255.255 1,024 4,194,302 4,194,304
11 255.224.0.0 FF.E0.0.0 0.31.255.255 2,048 2,097,150 2,097,152
12 255.240.0.0 FF.F0.0.0 0.15.255.255 4,096 1,048,574 1,048,576
13 255.248.0.0 FF.F8.0.0 0.7.255.255 8,192 524,286 524,288
14 255.252.0.0 FF.FC.0.0 0.3.255.255 16,384 262,142 262,144
15 255.254.0.0 FF.FE.0.0 0.1.255.255 32,768 131,070 131,072
16 255.255.0.0 FF.FF.0.0 0.0.255.255 65,536 65,534 65,536
Bits Netmask Hexmask Wildcard Sub Networks Host IPs Binary
17 255.255.128.0 FF.FF.80.0 0.0.127.255 131,072 32,766 32,768
18 255.255.192.0 FF.FF.C0.0 0.0.63.255 262,144 16,382 16,384
19 255.255.224.0 FF.FF.E0.0 0.0.31.255 524,288 8,190 8,192
20 255.255.240.0 FF.FF.F0.0 0.0.15.255 1,048,576 4,094 4,096
21 255.255.248.0 FF.FF.F8.0 0.0.7.255 2,097,152 2,046 2,048
22 255.255.252.0 FF.FF.FC.0 0.0.3.255 4,194,304 1,022 1,024
23 255.255.254.0 FF.FF.FE.0 0.0.1.255 8,388,608 510 512
24 255.255.255.0 FF.FF.FF.0 0.0.0.255 16,777,216 254 256
Bits Netmask Hexmask Wildcard Sub Networks Host IPs Binary
25 255.255.255.128 FF.FF.FF.80 0.0.0.127 33,554,432 126 128
26 255.255.255.192 FF.FF.FF.C0 0.0.0.63 67,108,864 62 64
27 255.255.255.224 FF.FF.FF.E0 0.0.0.31 134,217,728 30 32
28 255.255.255.240 FF.FF.FF.F0 0.0.0.15 268,435,456 14 16
29 255.255.255.248 FF.FF.FF.F8 0.0.0.7 536,870,912 6 8
30 255.255.255.252 FF.FF.FF.FC 0.0.0.3 1,073,741,824 2 4
31 255.255.255.254 FF.FF.FF.FE 0.0.0.1 2
32 255.255.255.255 FF.FF.FF.FF 0.0.0.0 1
Bits Netmask Hexmask Wildcard Sub Networks Host IPs Binary