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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.

Network96.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
96.0.0.0
Broadcast address
96.127.255.255
First usable
96.0.0.1
Last usable
96.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 60000000 · Integer 1610612736 to 1619001343
Reverse DNS zones
0.96.in-addr.arpa
1.96.in-addr.arpa
2.96.in-addr.arpa
3.96.in-addr.arpa
4.96.in-addr.arpa
5.96.in-addr.arpa
6.96.in-addr.arpa
7.96.in-addr.arpa
8.96.in-addr.arpa
9.96.in-addr.arpa
10.96.in-addr.arpa
11.96.in-addr.arpa
12.96.in-addr.arpa
13.96.in-addr.arpa
14.96.in-addr.arpa
15.96.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100000.00000000.00000000.0000000096.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01100000.00000000.00000000.0000000096.0.0.0
Broadcast01100000.01111111.11111111.1111111196.127.255.255
Split into smaller subnets/18
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

96.0.0.0/9 makes 512 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
196.0.0.0/1896.0.0.1 to 96.0.63.25496.0.63.25516,382
296.0.64.0/1896.0.64.1 to 96.0.127.25496.0.127.25516,382
396.0.128.0/1896.0.128.1 to 96.0.191.25496.0.191.25516,382
496.0.192.0/1896.0.192.1 to 96.0.255.25496.0.255.25516,382
596.1.0.0/1896.1.0.1 to 96.1.63.25496.1.63.25516,382
696.1.64.0/1896.1.64.1 to 96.1.127.25496.1.127.25516,382
796.1.128.0/1896.1.128.1 to 96.1.191.25496.1.191.25516,382
896.1.192.0/1896.1.192.1 to 96.1.255.25496.1.255.25516,382
996.2.0.0/1896.2.0.1 to 96.2.63.25496.2.63.25516,382
1096.2.64.0/1896.2.64.1 to 96.2.127.25496.2.127.25516,382
1196.2.128.0/1896.2.128.1 to 96.2.191.25496.2.191.25516,382
1296.2.192.0/1896.2.192.1 to 96.2.255.25496.2.255.25516,382
1396.3.0.0/1896.3.0.1 to 96.3.63.25496.3.63.25516,382
1496.3.64.0/1896.3.64.1 to 96.3.127.25496.3.127.25516,382
1596.3.128.0/1896.3.128.1 to 96.3.191.25496.3.191.25516,382
1696.3.192.0/1896.3.192.1 to 96.3.255.25496.3.255.25516,382
1796.4.0.0/1896.4.0.1 to 96.4.63.25496.4.63.25516,382
1896.4.64.0/1896.4.64.1 to 96.4.127.25496.4.127.25516,382
1996.4.128.0/1896.4.128.1 to 96.4.191.25496.4.191.25516,382
2096.4.192.0/1896.4.192.1 to 96.4.255.25496.4.255.25516,382
2196.5.0.0/1896.5.0.1 to 96.5.63.25496.5.63.25516,382
2296.5.64.0/1896.5.64.1 to 96.5.127.25496.5.127.25516,382
2396.5.128.0/1896.5.128.1 to 96.5.191.25496.5.191.25516,382
2496.5.192.0/1896.5.192.1 to 96.5.255.25496.5.255.25516,382
2596.6.0.0/1896.6.0.1 to 96.6.63.25496.6.63.25516,382
2696.6.64.0/1896.6.64.1 to 96.6.127.25496.6.127.25516,382
2796.6.128.0/1896.6.128.1 to 96.6.191.25496.6.191.25516,382
2896.6.192.0/1896.6.192.1 to 96.6.255.25496.6.255.25516,382
2996.7.0.0/1896.7.0.1 to 96.7.63.25496.7.63.25516,382
3096.7.64.0/1896.7.64.1 to 96.7.127.25496.7.127.25516,382
3196.7.128.0/1896.7.128.1 to 96.7.191.25496.7.191.25516,382
3296.7.192.0/1896.7.192.1 to 96.7.255.25496.7.255.25516,382
3396.8.0.0/1896.8.0.1 to 96.8.63.25496.8.63.25516,382
3496.8.64.0/1896.8.64.1 to 96.8.127.25496.8.127.25516,382
3596.8.128.0/1896.8.128.1 to 96.8.191.25496.8.191.25516,382
3696.8.192.0/1896.8.192.1 to 96.8.255.25496.8.255.25516,382
3796.9.0.0/1896.9.0.1 to 96.9.63.25496.9.63.25516,382
3896.9.64.0/1896.9.64.1 to 96.9.127.25496.9.127.25516,382
3996.9.128.0/1896.9.128.1 to 96.9.191.25496.9.191.25516,382
4096.9.192.0/1896.9.192.1 to 96.9.255.25496.9.255.25516,382
4196.10.0.0/1896.10.0.1 to 96.10.63.25496.10.63.25516,382
4296.10.64.0/1896.10.64.1 to 96.10.127.25496.10.127.25516,382
4396.10.128.0/1896.10.128.1 to 96.10.191.25496.10.191.25516,382
4496.10.192.0/1896.10.192.1 to 96.10.255.25496.10.255.25516,382
4596.11.0.0/1896.11.0.1 to 96.11.63.25496.11.63.25516,382
4696.11.64.0/1896.11.64.1 to 96.11.127.25496.11.127.25516,382
4796.11.128.0/1896.11.128.1 to 96.11.191.25496.11.191.25516,382
4896.11.192.0/1896.11.192.1 to 96.11.255.25496.11.255.25516,382
4996.12.0.0/1896.12.0.1 to 96.12.63.25496.12.63.25516,382
5096.12.64.0/1896.12.64.1 to 96.12.127.25496.12.127.25516,382
5196.12.128.0/1896.12.128.1 to 96.12.191.25496.12.191.25516,382
5296.12.192.0/1896.12.192.1 to 96.12.255.25496.12.255.25516,382
5396.13.0.0/1896.13.0.1 to 96.13.63.25496.13.63.25516,382
5496.13.64.0/1896.13.64.1 to 96.13.127.25496.13.127.25516,382
5596.13.128.0/1896.13.128.1 to 96.13.191.25496.13.191.25516,382
5696.13.192.0/1896.13.192.1 to 96.13.255.25496.13.255.25516,382
5796.14.0.0/1896.14.0.1 to 96.14.63.25496.14.63.25516,382
5896.14.64.0/1896.14.64.1 to 96.14.127.25496.14.127.25516,382
5996.14.128.0/1896.14.128.1 to 96.14.191.25496.14.191.25516,382
6096.14.192.0/1896.14.192.1 to 96.14.255.25496.14.255.25516,382
6196.15.0.0/1896.15.0.1 to 96.15.63.25496.15.63.25516,382
6296.15.64.0/1896.15.64.1 to 96.15.127.25496.15.127.25516,382
6396.15.128.0/1896.15.128.1 to 96.15.191.25496.15.191.25516,382
6496.15.192.0/1896.15.192.1 to 96.15.255.25496.15.255.25516,382
6596.16.0.0/1896.16.0.1 to 96.16.63.25496.16.63.25516,382
6696.16.64.0/1896.16.64.1 to 96.16.127.25496.16.127.25516,382
6796.16.128.0/1896.16.128.1 to 96.16.191.25496.16.191.25516,382
6896.16.192.0/1896.16.192.1 to 96.16.255.25496.16.255.25516,382
6996.17.0.0/1896.17.0.1 to 96.17.63.25496.17.63.25516,382
7096.17.64.0/1896.17.64.1 to 96.17.127.25496.17.127.25516,382
7196.17.128.0/1896.17.128.1 to 96.17.191.25496.17.191.25516,382
7296.17.192.0/1896.17.192.1 to 96.17.255.25496.17.255.25516,382
7396.18.0.0/1896.18.0.1 to 96.18.63.25496.18.63.25516,382
7496.18.64.0/1896.18.64.1 to 96.18.127.25496.18.127.25516,382
7596.18.128.0/1896.18.128.1 to 96.18.191.25496.18.191.25516,382
7696.18.192.0/1896.18.192.1 to 96.18.255.25496.18.255.25516,382
7796.19.0.0/1896.19.0.1 to 96.19.63.25496.19.63.25516,382
7896.19.64.0/1896.19.64.1 to 96.19.127.25496.19.127.25516,382
7996.19.128.0/1896.19.128.1 to 96.19.191.25496.19.191.25516,382
8096.19.192.0/1896.19.192.1 to 96.19.255.25496.19.255.25516,382
8196.20.0.0/1896.20.0.1 to 96.20.63.25496.20.63.25516,382
8296.20.64.0/1896.20.64.1 to 96.20.127.25496.20.127.25516,382
8396.20.128.0/1896.20.128.1 to 96.20.191.25496.20.191.25516,382
8496.20.192.0/1896.20.192.1 to 96.20.255.25496.20.255.25516,382
8596.21.0.0/1896.21.0.1 to 96.21.63.25496.21.63.25516,382
8696.21.64.0/1896.21.64.1 to 96.21.127.25496.21.127.25516,382
8796.21.128.0/1896.21.128.1 to 96.21.191.25496.21.191.25516,382
8896.21.192.0/1896.21.192.1 to 96.21.255.25496.21.255.25516,382
8996.22.0.0/1896.22.0.1 to 96.22.63.25496.22.63.25516,382
9096.22.64.0/1896.22.64.1 to 96.22.127.25496.22.127.25516,382
9196.22.128.0/1896.22.128.1 to 96.22.191.25496.22.191.25516,382
9296.22.192.0/1896.22.192.1 to 96.22.255.25496.22.255.25516,382
9396.23.0.0/1896.23.0.1 to 96.23.63.25496.23.63.25516,382
9496.23.64.0/1896.23.64.1 to 96.23.127.25496.23.127.25516,382
9596.23.128.0/1896.23.128.1 to 96.23.191.25496.23.191.25516,382
9696.23.192.0/1896.23.192.1 to 96.23.255.25496.23.255.25516,382
9796.24.0.0/1896.24.0.1 to 96.24.63.25496.24.63.25516,382
9896.24.64.0/1896.24.64.1 to 96.24.127.25496.24.127.25516,382
9996.24.128.0/1896.24.128.1 to 96.24.191.25496.24.191.25516,382
10096.24.192.0/1896.24.192.1 to 96.24.255.25496.24.255.25516,382
10196.25.0.0/1896.25.0.1 to 96.25.63.25496.25.63.25516,382
10296.25.64.0/1896.25.64.1 to 96.25.127.25496.25.127.25516,382
10396.25.128.0/1896.25.128.1 to 96.25.191.25496.25.191.25516,382
10496.25.192.0/1896.25.192.1 to 96.25.255.25496.25.255.25516,382
10596.26.0.0/1896.26.0.1 to 96.26.63.25496.26.63.25516,382
10696.26.64.0/1896.26.64.1 to 96.26.127.25496.26.127.25516,382
10796.26.128.0/1896.26.128.1 to 96.26.191.25496.26.191.25516,382
10896.26.192.0/1896.26.192.1 to 96.26.255.25496.26.255.25516,382
10996.27.0.0/1896.27.0.1 to 96.27.63.25496.27.63.25516,382
11096.27.64.0/1896.27.64.1 to 96.27.127.25496.27.127.25516,382
11196.27.128.0/1896.27.128.1 to 96.27.191.25496.27.191.25516,382
11296.27.192.0/1896.27.192.1 to 96.27.255.25496.27.255.25516,382
11396.28.0.0/1896.28.0.1 to 96.28.63.25496.28.63.25516,382
11496.28.64.0/1896.28.64.1 to 96.28.127.25496.28.127.25516,382
11596.28.128.0/1896.28.128.1 to 96.28.191.25496.28.191.25516,382
11696.28.192.0/1896.28.192.1 to 96.28.255.25496.28.255.25516,382
11796.29.0.0/1896.29.0.1 to 96.29.63.25496.29.63.25516,382
11896.29.64.0/1896.29.64.1 to 96.29.127.25496.29.127.25516,382
11996.29.128.0/1896.29.128.1 to 96.29.191.25496.29.191.25516,382
12096.29.192.0/1896.29.192.1 to 96.29.255.25496.29.255.25516,382
12196.30.0.0/1896.30.0.1 to 96.30.63.25496.30.63.25516,382
12296.30.64.0/1896.30.64.1 to 96.30.127.25496.30.127.25516,382
12396.30.128.0/1896.30.128.1 to 96.30.191.25496.30.191.25516,382
12496.30.192.0/1896.30.192.1 to 96.30.255.25496.30.255.25516,382
12596.31.0.0/1896.31.0.1 to 96.31.63.25496.31.63.25516,382
12696.31.64.0/1896.31.64.1 to 96.31.127.25496.31.127.25516,382
12796.31.128.0/1896.31.128.1 to 96.31.191.25496.31.191.25516,382
12896.31.192.0/1896.31.192.1 to 96.31.255.25496.31.255.25516,382
12996.32.0.0/1896.32.0.1 to 96.32.63.25496.32.63.25516,382
13096.32.64.0/1896.32.64.1 to 96.32.127.25496.32.127.25516,382
13196.32.128.0/1896.32.128.1 to 96.32.191.25496.32.191.25516,382
13296.32.192.0/1896.32.192.1 to 96.32.255.25496.32.255.25516,382
13396.33.0.0/1896.33.0.1 to 96.33.63.25496.33.63.25516,382
13496.33.64.0/1896.33.64.1 to 96.33.127.25496.33.127.25516,382
13596.33.128.0/1896.33.128.1 to 96.33.191.25496.33.191.25516,382
13696.33.192.0/1896.33.192.1 to 96.33.255.25496.33.255.25516,382
13796.34.0.0/1896.34.0.1 to 96.34.63.25496.34.63.25516,382
13896.34.64.0/1896.34.64.1 to 96.34.127.25496.34.127.25516,382
13996.34.128.0/1896.34.128.1 to 96.34.191.25496.34.191.25516,382
14096.34.192.0/1896.34.192.1 to 96.34.255.25496.34.255.25516,382
14196.35.0.0/1896.35.0.1 to 96.35.63.25496.35.63.25516,382
14296.35.64.0/1896.35.64.1 to 96.35.127.25496.35.127.25516,382
14396.35.128.0/1896.35.128.1 to 96.35.191.25496.35.191.25516,382
14496.35.192.0/1896.35.192.1 to 96.35.255.25496.35.255.25516,382
14596.36.0.0/1896.36.0.1 to 96.36.63.25496.36.63.25516,382
14696.36.64.0/1896.36.64.1 to 96.36.127.25496.36.127.25516,382
14796.36.128.0/1896.36.128.1 to 96.36.191.25496.36.191.25516,382
14896.36.192.0/1896.36.192.1 to 96.36.255.25496.36.255.25516,382
14996.37.0.0/1896.37.0.1 to 96.37.63.25496.37.63.25516,382
15096.37.64.0/1896.37.64.1 to 96.37.127.25496.37.127.25516,382
15196.37.128.0/1896.37.128.1 to 96.37.191.25496.37.191.25516,382
15296.37.192.0/1896.37.192.1 to 96.37.255.25496.37.255.25516,382
15396.38.0.0/1896.38.0.1 to 96.38.63.25496.38.63.25516,382
15496.38.64.0/1896.38.64.1 to 96.38.127.25496.38.127.25516,382
15596.38.128.0/1896.38.128.1 to 96.38.191.25496.38.191.25516,382
15696.38.192.0/1896.38.192.1 to 96.38.255.25496.38.255.25516,382
15796.39.0.0/1896.39.0.1 to 96.39.63.25496.39.63.25516,382
15896.39.64.0/1896.39.64.1 to 96.39.127.25496.39.127.25516,382
15996.39.128.0/1896.39.128.1 to 96.39.191.25496.39.191.25516,382
16096.39.192.0/1896.39.192.1 to 96.39.255.25496.39.255.25516,382
16196.40.0.0/1896.40.0.1 to 96.40.63.25496.40.63.25516,382
16296.40.64.0/1896.40.64.1 to 96.40.127.25496.40.127.25516,382
16396.40.128.0/1896.40.128.1 to 96.40.191.25496.40.191.25516,382
16496.40.192.0/1896.40.192.1 to 96.40.255.25496.40.255.25516,382
16596.41.0.0/1896.41.0.1 to 96.41.63.25496.41.63.25516,382
16696.41.64.0/1896.41.64.1 to 96.41.127.25496.41.127.25516,382
16796.41.128.0/1896.41.128.1 to 96.41.191.25496.41.191.25516,382
16896.41.192.0/1896.41.192.1 to 96.41.255.25496.41.255.25516,382
16996.42.0.0/1896.42.0.1 to 96.42.63.25496.42.63.25516,382
17096.42.64.0/1896.42.64.1 to 96.42.127.25496.42.127.25516,382
17196.42.128.0/1896.42.128.1 to 96.42.191.25496.42.191.25516,382
17296.42.192.0/1896.42.192.1 to 96.42.255.25496.42.255.25516,382
17396.43.0.0/1896.43.0.1 to 96.43.63.25496.43.63.25516,382
17496.43.64.0/1896.43.64.1 to 96.43.127.25496.43.127.25516,382
17596.43.128.0/1896.43.128.1 to 96.43.191.25496.43.191.25516,382
17696.43.192.0/1896.43.192.1 to 96.43.255.25496.43.255.25516,382
17796.44.0.0/1896.44.0.1 to 96.44.63.25496.44.63.25516,382
17896.44.64.0/1896.44.64.1 to 96.44.127.25496.44.127.25516,382
17996.44.128.0/1896.44.128.1 to 96.44.191.25496.44.191.25516,382
18096.44.192.0/1896.44.192.1 to 96.44.255.25496.44.255.25516,382
18196.45.0.0/1896.45.0.1 to 96.45.63.25496.45.63.25516,382
18296.45.64.0/1896.45.64.1 to 96.45.127.25496.45.127.25516,382
18396.45.128.0/1896.45.128.1 to 96.45.191.25496.45.191.25516,382
18496.45.192.0/1896.45.192.1 to 96.45.255.25496.45.255.25516,382
18596.46.0.0/1896.46.0.1 to 96.46.63.25496.46.63.25516,382
18696.46.64.0/1896.46.64.1 to 96.46.127.25496.46.127.25516,382
18796.46.128.0/1896.46.128.1 to 96.46.191.25496.46.191.25516,382
18896.46.192.0/1896.46.192.1 to 96.46.255.25496.46.255.25516,382
18996.47.0.0/1896.47.0.1 to 96.47.63.25496.47.63.25516,382
19096.47.64.0/1896.47.64.1 to 96.47.127.25496.47.127.25516,382
19196.47.128.0/1896.47.128.1 to 96.47.191.25496.47.191.25516,382
19296.47.192.0/1896.47.192.1 to 96.47.255.25496.47.255.25516,382
19396.48.0.0/1896.48.0.1 to 96.48.63.25496.48.63.25516,382
19496.48.64.0/1896.48.64.1 to 96.48.127.25496.48.127.25516,382
19596.48.128.0/1896.48.128.1 to 96.48.191.25496.48.191.25516,382
19696.48.192.0/1896.48.192.1 to 96.48.255.25496.48.255.25516,382
19796.49.0.0/1896.49.0.1 to 96.49.63.25496.49.63.25516,382
19896.49.64.0/1896.49.64.1 to 96.49.127.25496.49.127.25516,382
19996.49.128.0/1896.49.128.1 to 96.49.191.25496.49.191.25516,382
20096.49.192.0/1896.49.192.1 to 96.49.255.25496.49.255.25516,382
20196.50.0.0/1896.50.0.1 to 96.50.63.25496.50.63.25516,382
20296.50.64.0/1896.50.64.1 to 96.50.127.25496.50.127.25516,382
20396.50.128.0/1896.50.128.1 to 96.50.191.25496.50.191.25516,382
20496.50.192.0/1896.50.192.1 to 96.50.255.25496.50.255.25516,382
20596.51.0.0/1896.51.0.1 to 96.51.63.25496.51.63.25516,382
20696.51.64.0/1896.51.64.1 to 96.51.127.25496.51.127.25516,382
20796.51.128.0/1896.51.128.1 to 96.51.191.25496.51.191.25516,382
20896.51.192.0/1896.51.192.1 to 96.51.255.25496.51.255.25516,382
20996.52.0.0/1896.52.0.1 to 96.52.63.25496.52.63.25516,382
21096.52.64.0/1896.52.64.1 to 96.52.127.25496.52.127.25516,382
21196.52.128.0/1896.52.128.1 to 96.52.191.25496.52.191.25516,382
21296.52.192.0/1896.52.192.1 to 96.52.255.25496.52.255.25516,382
21396.53.0.0/1896.53.0.1 to 96.53.63.25496.53.63.25516,382
21496.53.64.0/1896.53.64.1 to 96.53.127.25496.53.127.25516,382
21596.53.128.0/1896.53.128.1 to 96.53.191.25496.53.191.25516,382
21696.53.192.0/1896.53.192.1 to 96.53.255.25496.53.255.25516,382
21796.54.0.0/1896.54.0.1 to 96.54.63.25496.54.63.25516,382
21896.54.64.0/1896.54.64.1 to 96.54.127.25496.54.127.25516,382
21996.54.128.0/1896.54.128.1 to 96.54.191.25496.54.191.25516,382
22096.54.192.0/1896.54.192.1 to 96.54.255.25496.54.255.25516,382
22196.55.0.0/1896.55.0.1 to 96.55.63.25496.55.63.25516,382
22296.55.64.0/1896.55.64.1 to 96.55.127.25496.55.127.25516,382
22396.55.128.0/1896.55.128.1 to 96.55.191.25496.55.191.25516,382
22496.55.192.0/1896.55.192.1 to 96.55.255.25496.55.255.25516,382
22596.56.0.0/1896.56.0.1 to 96.56.63.25496.56.63.25516,382
22696.56.64.0/1896.56.64.1 to 96.56.127.25496.56.127.25516,382
22796.56.128.0/1896.56.128.1 to 96.56.191.25496.56.191.25516,382
22896.56.192.0/1896.56.192.1 to 96.56.255.25496.56.255.25516,382
22996.57.0.0/1896.57.0.1 to 96.57.63.25496.57.63.25516,382
23096.57.64.0/1896.57.64.1 to 96.57.127.25496.57.127.25516,382
23196.57.128.0/1896.57.128.1 to 96.57.191.25496.57.191.25516,382
23296.57.192.0/1896.57.192.1 to 96.57.255.25496.57.255.25516,382
23396.58.0.0/1896.58.0.1 to 96.58.63.25496.58.63.25516,382
23496.58.64.0/1896.58.64.1 to 96.58.127.25496.58.127.25516,382
23596.58.128.0/1896.58.128.1 to 96.58.191.25496.58.191.25516,382
23696.58.192.0/1896.58.192.1 to 96.58.255.25496.58.255.25516,382
23796.59.0.0/1896.59.0.1 to 96.59.63.25496.59.63.25516,382
23896.59.64.0/1896.59.64.1 to 96.59.127.25496.59.127.25516,382
23996.59.128.0/1896.59.128.1 to 96.59.191.25496.59.191.25516,382
24096.59.192.0/1896.59.192.1 to 96.59.255.25496.59.255.25516,382
24196.60.0.0/1896.60.0.1 to 96.60.63.25496.60.63.25516,382
24296.60.64.0/1896.60.64.1 to 96.60.127.25496.60.127.25516,382
24396.60.128.0/1896.60.128.1 to 96.60.191.25496.60.191.25516,382
24496.60.192.0/1896.60.192.1 to 96.60.255.25496.60.255.25516,382
24596.61.0.0/1896.61.0.1 to 96.61.63.25496.61.63.25516,382
24696.61.64.0/1896.61.64.1 to 96.61.127.25496.61.127.25516,382
24796.61.128.0/1896.61.128.1 to 96.61.191.25496.61.191.25516,382
24896.61.192.0/1896.61.192.1 to 96.61.255.25496.61.255.25516,382
24996.62.0.0/1896.62.0.1 to 96.62.63.25496.62.63.25516,382
25096.62.64.0/1896.62.64.1 to 96.62.127.25496.62.127.25516,382
25196.62.128.0/1896.62.128.1 to 96.62.191.25496.62.191.25516,382
25296.62.192.0/1896.62.192.1 to 96.62.255.25496.62.255.25516,382
25396.63.0.0/1896.63.0.1 to 96.63.63.25496.63.63.25516,382
25496.63.64.0/1896.63.64.1 to 96.63.127.25496.63.127.25516,382
25596.63.128.0/1896.63.128.1 to 96.63.191.25496.63.191.25516,382
25696.63.192.0/1896.63.192.1 to 96.63.255.25496.63.255.25516,382

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.