Here are some basic tools and quick references to save time when you're NetOp'n.
Send me an email to [email protected] and let me know if you would like any additions to this page.
| Subnet Mask | Binary Mask | CIDR | Usable Addresses |
|---|---|---|---|
| 255.255.255.255 | 11111111.11111111.11111111.11111111 | /32 | Host |
| 255.255.255.254 | 11111111.11111111.11111111.11111110 | /31 | Point-to-Point |
| 255.255.255.252 | 11111111.11111111.11111111.11111100 | /30 | 4 |
| 255.255.255.248 | 11111111.11111111.11111111.11111000 | /29 | 8 |
| 255.255.255.240 | 11111111.11111111.11111111.11110000 | /28 | 16 |
| 255.255.255.224 | 11111111.11111111.11111111.11100000 | /27 | 32 |
| 255.255.255.192 | 11111111.11111111.11111111.11000000 | /26 | 64 |
| 255.255.255.128 | 11111111.11111111.11111111.10000000 | /25 | 128 |
| 255.255.255.0 | 11111111.11111111.11111111.00000000 | /24 | 256 |
| 255.255.254.0 | 11111111.11111111.11111110.00000000 | /23 | 512 |
| 255.255.252.0 | 11111111.11111111.11111100.00000000 | /22 | 1024 |
| 255.255.248.0 | 11111111.11111111.11111000.00000000 | /21 | 2048 |
| 255.255.240.0 | 11111111.11111111.11110000.00000000 | /20 | 4096 |
| 255.255.224.0 | 11111111.11111111.11100000.00000000 | /19 | 8192 |
| 255.255.192.0 | 11111111.11111111.11000000.00000000 | /18 | 16384 |
| 255.255.128.0 | 11111111.11111111.10000000.00000000 | /17 | 32768 |
| 255.255.0.0 | 11111111.11111111.00000000.00000000 | /16 | 65536 |
| 255.254.0.0 | 11111111.11111110.00000000.00000000 | /15 | 131072 |
| 255.252.0.0 | 11111111.11111100.00000000.00000000 | /14 | 262144 |
| 255.248.0.0 | 11111111.11111000.00000000.00000000 | /13 | 524288 |
| 255.240.0.0 | 11111111.11110000.00000000.00000000 | /12 | 1048576 |
| 255.224.0.0 | 11111111.11100000.00000000.00000000 | /11 | 2097152 |
| 255.192.0.0 | 11111111.11000000.00000000.00000000 | /10 | 4194304 |
| 255.128.0.0 | 11111111.10000000.00000000.00000000 | /9 | 8388608 |
| 255.0.0.0 | 11111111.00000000.00000000.00000000 | /8 | 16777216 |
| 254.0.0.0 | 11111110.00000000.00000000.00000000 | /7 | 33554432 |
| 252.0.0.0 | 11111100.00000000.00000000.00000000 | /6 | 67108864 |
| 248.0.0.0 | 11111000.00000000.00000000.00000000 | /5 | 134217728 |
| 240.0.0.0 | 11110000.00000000.00000000.00000000 | /4 | 268435456 |
| 224.0.0.0 | 11100000.00000000.00000000.00000000 | /3 | 536870912 |
| 192.0.0.0 | 11000000.00000000.00000000.00000000 | /2 | 1073741824 |
| 128.0.0.0 | 10000000.00000000.00000000.00000000 | /1 | 2147483648 |
| 0.0.0.0 | 00000000.00000000.00000000.00000000 | /0 | 4294967296 |
| Addresses | Notes |
|---|---|
| 0/8 | Broadcast |
| 10/8 | RFC 1918 |
| 127/8 | Loopback |
| 169.254.0/16 | Link Local |
| 172.16.0.0/12 | RFC 1918 |
| 192.0.2.0/24 | TEST-NET |
| 192.168.0/16 | RFC 1918 |
| 224.0.0.0/4 | Class D Multicast |
| 240.0.0.0/5 | Class E Reserved |
| 248.0.0.0/5 | Reserved |
| 255.255.255.255/32 | Broadcast |
This site is designed for a minimum horizontal resolution of 1250 pixels.
If you are using tablet you may be able to resolve this by turning it to a landscape orientation,
otherwise you can continue using the button below but the site may not work as intended.