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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network94.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
94.0.0.0
Broadcast address
95.255.255.255
First usable
94.0.0.1
Last usable
95.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 5E000000 · Integer 1577058304 to 1610612735
Reverse DNS zones
94.in-addr.arpa
95.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011110.00000000.00000000.0000000094.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network01011110.00000000.00000000.0000000094.0.0.0
Broadcast01011111.11111111.11111111.1111111195.255.255.255
Split into smaller subnets/19
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

94.0.0.0/7 makes 4,096 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
194.0.0.0/1994.0.0.1 to 94.0.31.25494.0.31.2558,190
294.0.32.0/1994.0.32.1 to 94.0.63.25494.0.63.2558,190
394.0.64.0/1994.0.64.1 to 94.0.95.25494.0.95.2558,190
494.0.96.0/1994.0.96.1 to 94.0.127.25494.0.127.2558,190
594.0.128.0/1994.0.128.1 to 94.0.159.25494.0.159.2558,190
694.0.160.0/1994.0.160.1 to 94.0.191.25494.0.191.2558,190
794.0.192.0/1994.0.192.1 to 94.0.223.25494.0.223.2558,190
894.0.224.0/1994.0.224.1 to 94.0.255.25494.0.255.2558,190
994.1.0.0/1994.1.0.1 to 94.1.31.25494.1.31.2558,190
1094.1.32.0/1994.1.32.1 to 94.1.63.25494.1.63.2558,190
1194.1.64.0/1994.1.64.1 to 94.1.95.25494.1.95.2558,190
1294.1.96.0/1994.1.96.1 to 94.1.127.25494.1.127.2558,190
1394.1.128.0/1994.1.128.1 to 94.1.159.25494.1.159.2558,190
1494.1.160.0/1994.1.160.1 to 94.1.191.25494.1.191.2558,190
1594.1.192.0/1994.1.192.1 to 94.1.223.25494.1.223.2558,190
1694.1.224.0/1994.1.224.1 to 94.1.255.25494.1.255.2558,190
1794.2.0.0/1994.2.0.1 to 94.2.31.25494.2.31.2558,190
1894.2.32.0/1994.2.32.1 to 94.2.63.25494.2.63.2558,190
1994.2.64.0/1994.2.64.1 to 94.2.95.25494.2.95.2558,190
2094.2.96.0/1994.2.96.1 to 94.2.127.25494.2.127.2558,190
2194.2.128.0/1994.2.128.1 to 94.2.159.25494.2.159.2558,190
2294.2.160.0/1994.2.160.1 to 94.2.191.25494.2.191.2558,190
2394.2.192.0/1994.2.192.1 to 94.2.223.25494.2.223.2558,190
2494.2.224.0/1994.2.224.1 to 94.2.255.25494.2.255.2558,190
2594.3.0.0/1994.3.0.1 to 94.3.31.25494.3.31.2558,190
2694.3.32.0/1994.3.32.1 to 94.3.63.25494.3.63.2558,190
2794.3.64.0/1994.3.64.1 to 94.3.95.25494.3.95.2558,190
2894.3.96.0/1994.3.96.1 to 94.3.127.25494.3.127.2558,190
2994.3.128.0/1994.3.128.1 to 94.3.159.25494.3.159.2558,190
3094.3.160.0/1994.3.160.1 to 94.3.191.25494.3.191.2558,190
3194.3.192.0/1994.3.192.1 to 94.3.223.25494.3.223.2558,190
3294.3.224.0/1994.3.224.1 to 94.3.255.25494.3.255.2558,190
3394.4.0.0/1994.4.0.1 to 94.4.31.25494.4.31.2558,190
3494.4.32.0/1994.4.32.1 to 94.4.63.25494.4.63.2558,190
3594.4.64.0/1994.4.64.1 to 94.4.95.25494.4.95.2558,190
3694.4.96.0/1994.4.96.1 to 94.4.127.25494.4.127.2558,190
3794.4.128.0/1994.4.128.1 to 94.4.159.25494.4.159.2558,190
3894.4.160.0/1994.4.160.1 to 94.4.191.25494.4.191.2558,190
3994.4.192.0/1994.4.192.1 to 94.4.223.25494.4.223.2558,190
4094.4.224.0/1994.4.224.1 to 94.4.255.25494.4.255.2558,190
4194.5.0.0/1994.5.0.1 to 94.5.31.25494.5.31.2558,190
4294.5.32.0/1994.5.32.1 to 94.5.63.25494.5.63.2558,190
4394.5.64.0/1994.5.64.1 to 94.5.95.25494.5.95.2558,190
4494.5.96.0/1994.5.96.1 to 94.5.127.25494.5.127.2558,190
4594.5.128.0/1994.5.128.1 to 94.5.159.25494.5.159.2558,190
4694.5.160.0/1994.5.160.1 to 94.5.191.25494.5.191.2558,190
4794.5.192.0/1994.5.192.1 to 94.5.223.25494.5.223.2558,190
4894.5.224.0/1994.5.224.1 to 94.5.255.25494.5.255.2558,190
4994.6.0.0/1994.6.0.1 to 94.6.31.25494.6.31.2558,190
5094.6.32.0/1994.6.32.1 to 94.6.63.25494.6.63.2558,190
5194.6.64.0/1994.6.64.1 to 94.6.95.25494.6.95.2558,190
5294.6.96.0/1994.6.96.1 to 94.6.127.25494.6.127.2558,190
5394.6.128.0/1994.6.128.1 to 94.6.159.25494.6.159.2558,190
5494.6.160.0/1994.6.160.1 to 94.6.191.25494.6.191.2558,190
5594.6.192.0/1994.6.192.1 to 94.6.223.25494.6.223.2558,190
5694.6.224.0/1994.6.224.1 to 94.6.255.25494.6.255.2558,190
5794.7.0.0/1994.7.0.1 to 94.7.31.25494.7.31.2558,190
5894.7.32.0/1994.7.32.1 to 94.7.63.25494.7.63.2558,190
5994.7.64.0/1994.7.64.1 to 94.7.95.25494.7.95.2558,190
6094.7.96.0/1994.7.96.1 to 94.7.127.25494.7.127.2558,190
6194.7.128.0/1994.7.128.1 to 94.7.159.25494.7.159.2558,190
6294.7.160.0/1994.7.160.1 to 94.7.191.25494.7.191.2558,190
6394.7.192.0/1994.7.192.1 to 94.7.223.25494.7.223.2558,190
6494.7.224.0/1994.7.224.1 to 94.7.255.25494.7.255.2558,190
6594.8.0.0/1994.8.0.1 to 94.8.31.25494.8.31.2558,190
6694.8.32.0/1994.8.32.1 to 94.8.63.25494.8.63.2558,190
6794.8.64.0/1994.8.64.1 to 94.8.95.25494.8.95.2558,190
6894.8.96.0/1994.8.96.1 to 94.8.127.25494.8.127.2558,190
6994.8.128.0/1994.8.128.1 to 94.8.159.25494.8.159.2558,190
7094.8.160.0/1994.8.160.1 to 94.8.191.25494.8.191.2558,190
7194.8.192.0/1994.8.192.1 to 94.8.223.25494.8.223.2558,190
7294.8.224.0/1994.8.224.1 to 94.8.255.25494.8.255.2558,190
7394.9.0.0/1994.9.0.1 to 94.9.31.25494.9.31.2558,190
7494.9.32.0/1994.9.32.1 to 94.9.63.25494.9.63.2558,190
7594.9.64.0/1994.9.64.1 to 94.9.95.25494.9.95.2558,190
7694.9.96.0/1994.9.96.1 to 94.9.127.25494.9.127.2558,190
7794.9.128.0/1994.9.128.1 to 94.9.159.25494.9.159.2558,190
7894.9.160.0/1994.9.160.1 to 94.9.191.25494.9.191.2558,190
7994.9.192.0/1994.9.192.1 to 94.9.223.25494.9.223.2558,190
8094.9.224.0/1994.9.224.1 to 94.9.255.25494.9.255.2558,190
8194.10.0.0/1994.10.0.1 to 94.10.31.25494.10.31.2558,190
8294.10.32.0/1994.10.32.1 to 94.10.63.25494.10.63.2558,190
8394.10.64.0/1994.10.64.1 to 94.10.95.25494.10.95.2558,190
8494.10.96.0/1994.10.96.1 to 94.10.127.25494.10.127.2558,190
8594.10.128.0/1994.10.128.1 to 94.10.159.25494.10.159.2558,190
8694.10.160.0/1994.10.160.1 to 94.10.191.25494.10.191.2558,190
8794.10.192.0/1994.10.192.1 to 94.10.223.25494.10.223.2558,190
8894.10.224.0/1994.10.224.1 to 94.10.255.25494.10.255.2558,190
8994.11.0.0/1994.11.0.1 to 94.11.31.25494.11.31.2558,190
9094.11.32.0/1994.11.32.1 to 94.11.63.25494.11.63.2558,190
9194.11.64.0/1994.11.64.1 to 94.11.95.25494.11.95.2558,190
9294.11.96.0/1994.11.96.1 to 94.11.127.25494.11.127.2558,190
9394.11.128.0/1994.11.128.1 to 94.11.159.25494.11.159.2558,190
9494.11.160.0/1994.11.160.1 to 94.11.191.25494.11.191.2558,190
9594.11.192.0/1994.11.192.1 to 94.11.223.25494.11.223.2558,190
9694.11.224.0/1994.11.224.1 to 94.11.255.25494.11.255.2558,190
9794.12.0.0/1994.12.0.1 to 94.12.31.25494.12.31.2558,190
9894.12.32.0/1994.12.32.1 to 94.12.63.25494.12.63.2558,190
9994.12.64.0/1994.12.64.1 to 94.12.95.25494.12.95.2558,190
10094.12.96.0/1994.12.96.1 to 94.12.127.25494.12.127.2558,190
10194.12.128.0/1994.12.128.1 to 94.12.159.25494.12.159.2558,190
10294.12.160.0/1994.12.160.1 to 94.12.191.25494.12.191.2558,190
10394.12.192.0/1994.12.192.1 to 94.12.223.25494.12.223.2558,190
10494.12.224.0/1994.12.224.1 to 94.12.255.25494.12.255.2558,190
10594.13.0.0/1994.13.0.1 to 94.13.31.25494.13.31.2558,190
10694.13.32.0/1994.13.32.1 to 94.13.63.25494.13.63.2558,190
10794.13.64.0/1994.13.64.1 to 94.13.95.25494.13.95.2558,190
10894.13.96.0/1994.13.96.1 to 94.13.127.25494.13.127.2558,190
10994.13.128.0/1994.13.128.1 to 94.13.159.25494.13.159.2558,190
11094.13.160.0/1994.13.160.1 to 94.13.191.25494.13.191.2558,190
11194.13.192.0/1994.13.192.1 to 94.13.223.25494.13.223.2558,190
11294.13.224.0/1994.13.224.1 to 94.13.255.25494.13.255.2558,190
11394.14.0.0/1994.14.0.1 to 94.14.31.25494.14.31.2558,190
11494.14.32.0/1994.14.32.1 to 94.14.63.25494.14.63.2558,190
11594.14.64.0/1994.14.64.1 to 94.14.95.25494.14.95.2558,190
11694.14.96.0/1994.14.96.1 to 94.14.127.25494.14.127.2558,190
11794.14.128.0/1994.14.128.1 to 94.14.159.25494.14.159.2558,190
11894.14.160.0/1994.14.160.1 to 94.14.191.25494.14.191.2558,190
11994.14.192.0/1994.14.192.1 to 94.14.223.25494.14.223.2558,190
12094.14.224.0/1994.14.224.1 to 94.14.255.25494.14.255.2558,190
12194.15.0.0/1994.15.0.1 to 94.15.31.25494.15.31.2558,190
12294.15.32.0/1994.15.32.1 to 94.15.63.25494.15.63.2558,190
12394.15.64.0/1994.15.64.1 to 94.15.95.25494.15.95.2558,190
12494.15.96.0/1994.15.96.1 to 94.15.127.25494.15.127.2558,190
12594.15.128.0/1994.15.128.1 to 94.15.159.25494.15.159.2558,190
12694.15.160.0/1994.15.160.1 to 94.15.191.25494.15.191.2558,190
12794.15.192.0/1994.15.192.1 to 94.15.223.25494.15.223.2558,190
12894.15.224.0/1994.15.224.1 to 94.15.255.25494.15.255.2558,190
12994.16.0.0/1994.16.0.1 to 94.16.31.25494.16.31.2558,190
13094.16.32.0/1994.16.32.1 to 94.16.63.25494.16.63.2558,190
13194.16.64.0/1994.16.64.1 to 94.16.95.25494.16.95.2558,190
13294.16.96.0/1994.16.96.1 to 94.16.127.25494.16.127.2558,190
13394.16.128.0/1994.16.128.1 to 94.16.159.25494.16.159.2558,190
13494.16.160.0/1994.16.160.1 to 94.16.191.25494.16.191.2558,190
13594.16.192.0/1994.16.192.1 to 94.16.223.25494.16.223.2558,190
13694.16.224.0/1994.16.224.1 to 94.16.255.25494.16.255.2558,190
13794.17.0.0/1994.17.0.1 to 94.17.31.25494.17.31.2558,190
13894.17.32.0/1994.17.32.1 to 94.17.63.25494.17.63.2558,190
13994.17.64.0/1994.17.64.1 to 94.17.95.25494.17.95.2558,190
14094.17.96.0/1994.17.96.1 to 94.17.127.25494.17.127.2558,190
14194.17.128.0/1994.17.128.1 to 94.17.159.25494.17.159.2558,190
14294.17.160.0/1994.17.160.1 to 94.17.191.25494.17.191.2558,190
14394.17.192.0/1994.17.192.1 to 94.17.223.25494.17.223.2558,190
14494.17.224.0/1994.17.224.1 to 94.17.255.25494.17.255.2558,190
14594.18.0.0/1994.18.0.1 to 94.18.31.25494.18.31.2558,190
14694.18.32.0/1994.18.32.1 to 94.18.63.25494.18.63.2558,190
14794.18.64.0/1994.18.64.1 to 94.18.95.25494.18.95.2558,190
14894.18.96.0/1994.18.96.1 to 94.18.127.25494.18.127.2558,190
14994.18.128.0/1994.18.128.1 to 94.18.159.25494.18.159.2558,190
15094.18.160.0/1994.18.160.1 to 94.18.191.25494.18.191.2558,190
15194.18.192.0/1994.18.192.1 to 94.18.223.25494.18.223.2558,190
15294.18.224.0/1994.18.224.1 to 94.18.255.25494.18.255.2558,190
15394.19.0.0/1994.19.0.1 to 94.19.31.25494.19.31.2558,190
15494.19.32.0/1994.19.32.1 to 94.19.63.25494.19.63.2558,190
15594.19.64.0/1994.19.64.1 to 94.19.95.25494.19.95.2558,190
15694.19.96.0/1994.19.96.1 to 94.19.127.25494.19.127.2558,190
15794.19.128.0/1994.19.128.1 to 94.19.159.25494.19.159.2558,190
15894.19.160.0/1994.19.160.1 to 94.19.191.25494.19.191.2558,190
15994.19.192.0/1994.19.192.1 to 94.19.223.25494.19.223.2558,190
16094.19.224.0/1994.19.224.1 to 94.19.255.25494.19.255.2558,190
16194.20.0.0/1994.20.0.1 to 94.20.31.25494.20.31.2558,190
16294.20.32.0/1994.20.32.1 to 94.20.63.25494.20.63.2558,190
16394.20.64.0/1994.20.64.1 to 94.20.95.25494.20.95.2558,190
16494.20.96.0/1994.20.96.1 to 94.20.127.25494.20.127.2558,190
16594.20.128.0/1994.20.128.1 to 94.20.159.25494.20.159.2558,190
16694.20.160.0/1994.20.160.1 to 94.20.191.25494.20.191.2558,190
16794.20.192.0/1994.20.192.1 to 94.20.223.25494.20.223.2558,190
16894.20.224.0/1994.20.224.1 to 94.20.255.25494.20.255.2558,190
16994.21.0.0/1994.21.0.1 to 94.21.31.25494.21.31.2558,190
17094.21.32.0/1994.21.32.1 to 94.21.63.25494.21.63.2558,190
17194.21.64.0/1994.21.64.1 to 94.21.95.25494.21.95.2558,190
17294.21.96.0/1994.21.96.1 to 94.21.127.25494.21.127.2558,190
17394.21.128.0/1994.21.128.1 to 94.21.159.25494.21.159.2558,190
17494.21.160.0/1994.21.160.1 to 94.21.191.25494.21.191.2558,190
17594.21.192.0/1994.21.192.1 to 94.21.223.25494.21.223.2558,190
17694.21.224.0/1994.21.224.1 to 94.21.255.25494.21.255.2558,190
17794.22.0.0/1994.22.0.1 to 94.22.31.25494.22.31.2558,190
17894.22.32.0/1994.22.32.1 to 94.22.63.25494.22.63.2558,190
17994.22.64.0/1994.22.64.1 to 94.22.95.25494.22.95.2558,190
18094.22.96.0/1994.22.96.1 to 94.22.127.25494.22.127.2558,190
18194.22.128.0/1994.22.128.1 to 94.22.159.25494.22.159.2558,190
18294.22.160.0/1994.22.160.1 to 94.22.191.25494.22.191.2558,190
18394.22.192.0/1994.22.192.1 to 94.22.223.25494.22.223.2558,190
18494.22.224.0/1994.22.224.1 to 94.22.255.25494.22.255.2558,190
18594.23.0.0/1994.23.0.1 to 94.23.31.25494.23.31.2558,190
18694.23.32.0/1994.23.32.1 to 94.23.63.25494.23.63.2558,190
18794.23.64.0/1994.23.64.1 to 94.23.95.25494.23.95.2558,190
18894.23.96.0/1994.23.96.1 to 94.23.127.25494.23.127.2558,190
18994.23.128.0/1994.23.128.1 to 94.23.159.25494.23.159.2558,190
19094.23.160.0/1994.23.160.1 to 94.23.191.25494.23.191.2558,190
19194.23.192.0/1994.23.192.1 to 94.23.223.25494.23.223.2558,190
19294.23.224.0/1994.23.224.1 to 94.23.255.25494.23.255.2558,190
19394.24.0.0/1994.24.0.1 to 94.24.31.25494.24.31.2558,190
19494.24.32.0/1994.24.32.1 to 94.24.63.25494.24.63.2558,190
19594.24.64.0/1994.24.64.1 to 94.24.95.25494.24.95.2558,190
19694.24.96.0/1994.24.96.1 to 94.24.127.25494.24.127.2558,190
19794.24.128.0/1994.24.128.1 to 94.24.159.25494.24.159.2558,190
19894.24.160.0/1994.24.160.1 to 94.24.191.25494.24.191.2558,190
19994.24.192.0/1994.24.192.1 to 94.24.223.25494.24.223.2558,190
20094.24.224.0/1994.24.224.1 to 94.24.255.25494.24.255.2558,190
20194.25.0.0/1994.25.0.1 to 94.25.31.25494.25.31.2558,190
20294.25.32.0/1994.25.32.1 to 94.25.63.25494.25.63.2558,190
20394.25.64.0/1994.25.64.1 to 94.25.95.25494.25.95.2558,190
20494.25.96.0/1994.25.96.1 to 94.25.127.25494.25.127.2558,190
20594.25.128.0/1994.25.128.1 to 94.25.159.25494.25.159.2558,190
20694.25.160.0/1994.25.160.1 to 94.25.191.25494.25.191.2558,190
20794.25.192.0/1994.25.192.1 to 94.25.223.25494.25.223.2558,190
20894.25.224.0/1994.25.224.1 to 94.25.255.25494.25.255.2558,190
20994.26.0.0/1994.26.0.1 to 94.26.31.25494.26.31.2558,190
21094.26.32.0/1994.26.32.1 to 94.26.63.25494.26.63.2558,190
21194.26.64.0/1994.26.64.1 to 94.26.95.25494.26.95.2558,190
21294.26.96.0/1994.26.96.1 to 94.26.127.25494.26.127.2558,190
21394.26.128.0/1994.26.128.1 to 94.26.159.25494.26.159.2558,190
21494.26.160.0/1994.26.160.1 to 94.26.191.25494.26.191.2558,190
21594.26.192.0/1994.26.192.1 to 94.26.223.25494.26.223.2558,190
21694.26.224.0/1994.26.224.1 to 94.26.255.25494.26.255.2558,190
21794.27.0.0/1994.27.0.1 to 94.27.31.25494.27.31.2558,190
21894.27.32.0/1994.27.32.1 to 94.27.63.25494.27.63.2558,190
21994.27.64.0/1994.27.64.1 to 94.27.95.25494.27.95.2558,190
22094.27.96.0/1994.27.96.1 to 94.27.127.25494.27.127.2558,190
22194.27.128.0/1994.27.128.1 to 94.27.159.25494.27.159.2558,190
22294.27.160.0/1994.27.160.1 to 94.27.191.25494.27.191.2558,190
22394.27.192.0/1994.27.192.1 to 94.27.223.25494.27.223.2558,190
22494.27.224.0/1994.27.224.1 to 94.27.255.25494.27.255.2558,190
22594.28.0.0/1994.28.0.1 to 94.28.31.25494.28.31.2558,190
22694.28.32.0/1994.28.32.1 to 94.28.63.25494.28.63.2558,190
22794.28.64.0/1994.28.64.1 to 94.28.95.25494.28.95.2558,190
22894.28.96.0/1994.28.96.1 to 94.28.127.25494.28.127.2558,190
22994.28.128.0/1994.28.128.1 to 94.28.159.25494.28.159.2558,190
23094.28.160.0/1994.28.160.1 to 94.28.191.25494.28.191.2558,190
23194.28.192.0/1994.28.192.1 to 94.28.223.25494.28.223.2558,190
23294.28.224.0/1994.28.224.1 to 94.28.255.25494.28.255.2558,190
23394.29.0.0/1994.29.0.1 to 94.29.31.25494.29.31.2558,190
23494.29.32.0/1994.29.32.1 to 94.29.63.25494.29.63.2558,190
23594.29.64.0/1994.29.64.1 to 94.29.95.25494.29.95.2558,190
23694.29.96.0/1994.29.96.1 to 94.29.127.25494.29.127.2558,190
23794.29.128.0/1994.29.128.1 to 94.29.159.25494.29.159.2558,190
23894.29.160.0/1994.29.160.1 to 94.29.191.25494.29.191.2558,190
23994.29.192.0/1994.29.192.1 to 94.29.223.25494.29.223.2558,190
24094.29.224.0/1994.29.224.1 to 94.29.255.25494.29.255.2558,190
24194.30.0.0/1994.30.0.1 to 94.30.31.25494.30.31.2558,190
24294.30.32.0/1994.30.32.1 to 94.30.63.25494.30.63.2558,190
24394.30.64.0/1994.30.64.1 to 94.30.95.25494.30.95.2558,190
24494.30.96.0/1994.30.96.1 to 94.30.127.25494.30.127.2558,190
24594.30.128.0/1994.30.128.1 to 94.30.159.25494.30.159.2558,190
24694.30.160.0/1994.30.160.1 to 94.30.191.25494.30.191.2558,190
24794.30.192.0/1994.30.192.1 to 94.30.223.25494.30.223.2558,190
24894.30.224.0/1994.30.224.1 to 94.30.255.25494.30.255.2558,190
24994.31.0.0/1994.31.0.1 to 94.31.31.25494.31.31.2558,190
25094.31.32.0/1994.31.32.1 to 94.31.63.25494.31.63.2558,190
25194.31.64.0/1994.31.64.1 to 94.31.95.25494.31.95.2558,190
25294.31.96.0/1994.31.96.1 to 94.31.127.25494.31.127.2558,190
25394.31.128.0/1994.31.128.1 to 94.31.159.25494.31.159.2558,190
25494.31.160.0/1994.31.160.1 to 94.31.191.25494.31.191.2558,190
25594.31.192.0/1994.31.192.1 to 94.31.223.25494.31.223.2558,190
25694.31.224.0/1994.31.224.1 to 94.31.255.25494.31.255.2558,190

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.