Skip to content

Instantly share code, notes, and snippets.

@miztiik
Last active April 7, 2019 18:12
Show Gist options
  • Save miztiik/baecbaa67b1f10e38186d70e51c13a6c to your computer and use it in GitHub Desktop.
Save miztiik/baecbaa67b1f10e38186d70e51c13a6c to your computer and use it in GitHub Desktop.
See in comments
@miztiik
Copy link
Author

miztiik commented Jul 20, 2016

CIDR Prefix Subnet Mask Total IP's Usable IP's Relative size to other block sizes
a.b.c.d**/32** 255.255.255.255 1 1 1/256 C
a.b.c.d**/31** 255.255.255.254 2 0 1/128 C
a.b.c.d**/30** 255.255.255.252 4 2 1/64 C
a.b.c.d**/29** 255.255.255.248 8 6 1/32 C
a.b.c.d**/28** 255.255.255.240 16 14 1/16 C
a.b.c.d**/27** 255.255.255.224 32 30 1/8 C
a.b.c.d**/26** 255.255.255.192 64 62 ¼ C
a.b.c.d**/25** 255.255.255.128 128 126 ½ C
a.b.c.0**/24** 255.255.255.0 256 254 1 C
a.b.c.0**/23** 255.255.254.0 512 510 2 C
a.b.c.0**/22** 255.255.252.0 1024 1022 4 C
a.b.c.0**/21** 255.255.248.0 2048 2046 8 C
a.b.c.0**/20** 255.255.240.0 4096 4094 16 C
a.b.c.0**/19** 255.255.224.0 8192 8190 32 C
a.b.c.0**/18** 255.255.192.0 16,384 16,382 64 C
a.b.c.0**/17** 255.255.128.0 32,768 32,766 128 C
a.b.0.0**/16** 255.255.0.0 65,536 65,534 256 C = 1 B
a.b.0.0**/15** 255.254.0.0 131,072 131,070 2 B
a.b.0.0**/14** 255.252.0.0 262,144 262,142 4 B
a.b.0.0**/13** 255.248.0.0 524,288 524,286 8 B
a.b.0.0**/12** 255.240.0.0 1,048,576 1,048,574 16 B
a.b.0.0**/11** 255.224.0.0 2,097,152 2,097,150 32 B
a.b.0.0**/10** 255.192.0.0 4,194,304 4,194,302 64 B
a.b.0.0**/9** 255.128.0.0 8,388,608 8,388,606 128 B
a.0.0.0**/8** 255.0.0.0 16,777,216 16,777,214 256 B = 1 A
a.0.0.0**/7** 254.0.0.0 33,554,432 33,554,430 2 A
a.0.0.0**/6** 252.0.0.0 67,108,864 67,108,862 4 A
a.0.0.0**/5** 248.0.0.0 134,217,728 134,217,726 8 A
a.0.0.0**/4** 240.0.0.0 268,435,456 268,435,454 16 A
a.0.0.0**/3** 224.0.0.0 536,870,912 536,870,910 32 A
a.0.0.0**/2** 192.0.0.0 1,073,741,824 1,073,741,822 64 A
a.0.0.0**/1** 128.0.0.0 2,147,483,648 2,147,483,646 128 A
0.0.0.0**/0** 0.0.0.0 4,294,967,296 4,294,967,294 256 A

@miztiik
Copy link
Author

miztiik commented Jul 21, 2016

Reserved Network Numbers

Class Start End # Hosts Comment
  A   10.0.0.0   10.255.255.255 16,777,216   a single Class A network number
  B   172.16.0.0   172.31.255.255 1,048,544   16 contiguous Class B network numbers
  C   192.168.0.0     192.168.255.255   65,534   256 contiguous Class C network numbers 

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment