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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/17
/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 256 subnets of /17.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
196.0.0.0/1796.0.0.1 to 96.0.127.25496.0.127.25532,766
296.0.128.0/1796.0.128.1 to 96.0.255.25496.0.255.25532,766
396.1.0.0/1796.1.0.1 to 96.1.127.25496.1.127.25532,766
496.1.128.0/1796.1.128.1 to 96.1.255.25496.1.255.25532,766
596.2.0.0/1796.2.0.1 to 96.2.127.25496.2.127.25532,766
696.2.128.0/1796.2.128.1 to 96.2.255.25496.2.255.25532,766
796.3.0.0/1796.3.0.1 to 96.3.127.25496.3.127.25532,766
896.3.128.0/1796.3.128.1 to 96.3.255.25496.3.255.25532,766
996.4.0.0/1796.4.0.1 to 96.4.127.25496.4.127.25532,766
1096.4.128.0/1796.4.128.1 to 96.4.255.25496.4.255.25532,766
1196.5.0.0/1796.5.0.1 to 96.5.127.25496.5.127.25532,766
1296.5.128.0/1796.5.128.1 to 96.5.255.25496.5.255.25532,766
1396.6.0.0/1796.6.0.1 to 96.6.127.25496.6.127.25532,766
1496.6.128.0/1796.6.128.1 to 96.6.255.25496.6.255.25532,766
1596.7.0.0/1796.7.0.1 to 96.7.127.25496.7.127.25532,766
1696.7.128.0/1796.7.128.1 to 96.7.255.25496.7.255.25532,766
1796.8.0.0/1796.8.0.1 to 96.8.127.25496.8.127.25532,766
1896.8.128.0/1796.8.128.1 to 96.8.255.25496.8.255.25532,766
1996.9.0.0/1796.9.0.1 to 96.9.127.25496.9.127.25532,766
2096.9.128.0/1796.9.128.1 to 96.9.255.25496.9.255.25532,766
2196.10.0.0/1796.10.0.1 to 96.10.127.25496.10.127.25532,766
2296.10.128.0/1796.10.128.1 to 96.10.255.25496.10.255.25532,766
2396.11.0.0/1796.11.0.1 to 96.11.127.25496.11.127.25532,766
2496.11.128.0/1796.11.128.1 to 96.11.255.25496.11.255.25532,766
2596.12.0.0/1796.12.0.1 to 96.12.127.25496.12.127.25532,766
2696.12.128.0/1796.12.128.1 to 96.12.255.25496.12.255.25532,766
2796.13.0.0/1796.13.0.1 to 96.13.127.25496.13.127.25532,766
2896.13.128.0/1796.13.128.1 to 96.13.255.25496.13.255.25532,766
2996.14.0.0/1796.14.0.1 to 96.14.127.25496.14.127.25532,766
3096.14.128.0/1796.14.128.1 to 96.14.255.25496.14.255.25532,766
3196.15.0.0/1796.15.0.1 to 96.15.127.25496.15.127.25532,766
3296.15.128.0/1796.15.128.1 to 96.15.255.25496.15.255.25532,766
3396.16.0.0/1796.16.0.1 to 96.16.127.25496.16.127.25532,766
3496.16.128.0/1796.16.128.1 to 96.16.255.25496.16.255.25532,766
3596.17.0.0/1796.17.0.1 to 96.17.127.25496.17.127.25532,766
3696.17.128.0/1796.17.128.1 to 96.17.255.25496.17.255.25532,766
3796.18.0.0/1796.18.0.1 to 96.18.127.25496.18.127.25532,766
3896.18.128.0/1796.18.128.1 to 96.18.255.25496.18.255.25532,766
3996.19.0.0/1796.19.0.1 to 96.19.127.25496.19.127.25532,766
4096.19.128.0/1796.19.128.1 to 96.19.255.25496.19.255.25532,766
4196.20.0.0/1796.20.0.1 to 96.20.127.25496.20.127.25532,766
4296.20.128.0/1796.20.128.1 to 96.20.255.25496.20.255.25532,766
4396.21.0.0/1796.21.0.1 to 96.21.127.25496.21.127.25532,766
4496.21.128.0/1796.21.128.1 to 96.21.255.25496.21.255.25532,766
4596.22.0.0/1796.22.0.1 to 96.22.127.25496.22.127.25532,766
4696.22.128.0/1796.22.128.1 to 96.22.255.25496.22.255.25532,766
4796.23.0.0/1796.23.0.1 to 96.23.127.25496.23.127.25532,766
4896.23.128.0/1796.23.128.1 to 96.23.255.25496.23.255.25532,766
4996.24.0.0/1796.24.0.1 to 96.24.127.25496.24.127.25532,766
5096.24.128.0/1796.24.128.1 to 96.24.255.25496.24.255.25532,766
5196.25.0.0/1796.25.0.1 to 96.25.127.25496.25.127.25532,766
5296.25.128.0/1796.25.128.1 to 96.25.255.25496.25.255.25532,766
5396.26.0.0/1796.26.0.1 to 96.26.127.25496.26.127.25532,766
5496.26.128.0/1796.26.128.1 to 96.26.255.25496.26.255.25532,766
5596.27.0.0/1796.27.0.1 to 96.27.127.25496.27.127.25532,766
5696.27.128.0/1796.27.128.1 to 96.27.255.25496.27.255.25532,766
5796.28.0.0/1796.28.0.1 to 96.28.127.25496.28.127.25532,766
5896.28.128.0/1796.28.128.1 to 96.28.255.25496.28.255.25532,766
5996.29.0.0/1796.29.0.1 to 96.29.127.25496.29.127.25532,766
6096.29.128.0/1796.29.128.1 to 96.29.255.25496.29.255.25532,766
6196.30.0.0/1796.30.0.1 to 96.30.127.25496.30.127.25532,766
6296.30.128.0/1796.30.128.1 to 96.30.255.25496.30.255.25532,766
6396.31.0.0/1796.31.0.1 to 96.31.127.25496.31.127.25532,766
6496.31.128.0/1796.31.128.1 to 96.31.255.25496.31.255.25532,766
6596.32.0.0/1796.32.0.1 to 96.32.127.25496.32.127.25532,766
6696.32.128.0/1796.32.128.1 to 96.32.255.25496.32.255.25532,766
6796.33.0.0/1796.33.0.1 to 96.33.127.25496.33.127.25532,766
6896.33.128.0/1796.33.128.1 to 96.33.255.25496.33.255.25532,766
6996.34.0.0/1796.34.0.1 to 96.34.127.25496.34.127.25532,766
7096.34.128.0/1796.34.128.1 to 96.34.255.25496.34.255.25532,766
7196.35.0.0/1796.35.0.1 to 96.35.127.25496.35.127.25532,766
7296.35.128.0/1796.35.128.1 to 96.35.255.25496.35.255.25532,766
7396.36.0.0/1796.36.0.1 to 96.36.127.25496.36.127.25532,766
7496.36.128.0/1796.36.128.1 to 96.36.255.25496.36.255.25532,766
7596.37.0.0/1796.37.0.1 to 96.37.127.25496.37.127.25532,766
7696.37.128.0/1796.37.128.1 to 96.37.255.25496.37.255.25532,766
7796.38.0.0/1796.38.0.1 to 96.38.127.25496.38.127.25532,766
7896.38.128.0/1796.38.128.1 to 96.38.255.25496.38.255.25532,766
7996.39.0.0/1796.39.0.1 to 96.39.127.25496.39.127.25532,766
8096.39.128.0/1796.39.128.1 to 96.39.255.25496.39.255.25532,766
8196.40.0.0/1796.40.0.1 to 96.40.127.25496.40.127.25532,766
8296.40.128.0/1796.40.128.1 to 96.40.255.25496.40.255.25532,766
8396.41.0.0/1796.41.0.1 to 96.41.127.25496.41.127.25532,766
8496.41.128.0/1796.41.128.1 to 96.41.255.25496.41.255.25532,766
8596.42.0.0/1796.42.0.1 to 96.42.127.25496.42.127.25532,766
8696.42.128.0/1796.42.128.1 to 96.42.255.25496.42.255.25532,766
8796.43.0.0/1796.43.0.1 to 96.43.127.25496.43.127.25532,766
8896.43.128.0/1796.43.128.1 to 96.43.255.25496.43.255.25532,766
8996.44.0.0/1796.44.0.1 to 96.44.127.25496.44.127.25532,766
9096.44.128.0/1796.44.128.1 to 96.44.255.25496.44.255.25532,766
9196.45.0.0/1796.45.0.1 to 96.45.127.25496.45.127.25532,766
9296.45.128.0/1796.45.128.1 to 96.45.255.25496.45.255.25532,766
9396.46.0.0/1796.46.0.1 to 96.46.127.25496.46.127.25532,766
9496.46.128.0/1796.46.128.1 to 96.46.255.25496.46.255.25532,766
9596.47.0.0/1796.47.0.1 to 96.47.127.25496.47.127.25532,766
9696.47.128.0/1796.47.128.1 to 96.47.255.25496.47.255.25532,766
9796.48.0.0/1796.48.0.1 to 96.48.127.25496.48.127.25532,766
9896.48.128.0/1796.48.128.1 to 96.48.255.25496.48.255.25532,766
9996.49.0.0/1796.49.0.1 to 96.49.127.25496.49.127.25532,766
10096.49.128.0/1796.49.128.1 to 96.49.255.25496.49.255.25532,766
10196.50.0.0/1796.50.0.1 to 96.50.127.25496.50.127.25532,766
10296.50.128.0/1796.50.128.1 to 96.50.255.25496.50.255.25532,766
10396.51.0.0/1796.51.0.1 to 96.51.127.25496.51.127.25532,766
10496.51.128.0/1796.51.128.1 to 96.51.255.25496.51.255.25532,766
10596.52.0.0/1796.52.0.1 to 96.52.127.25496.52.127.25532,766
10696.52.128.0/1796.52.128.1 to 96.52.255.25496.52.255.25532,766
10796.53.0.0/1796.53.0.1 to 96.53.127.25496.53.127.25532,766
10896.53.128.0/1796.53.128.1 to 96.53.255.25496.53.255.25532,766
10996.54.0.0/1796.54.0.1 to 96.54.127.25496.54.127.25532,766
11096.54.128.0/1796.54.128.1 to 96.54.255.25496.54.255.25532,766
11196.55.0.0/1796.55.0.1 to 96.55.127.25496.55.127.25532,766
11296.55.128.0/1796.55.128.1 to 96.55.255.25496.55.255.25532,766
11396.56.0.0/1796.56.0.1 to 96.56.127.25496.56.127.25532,766
11496.56.128.0/1796.56.128.1 to 96.56.255.25496.56.255.25532,766
11596.57.0.0/1796.57.0.1 to 96.57.127.25496.57.127.25532,766
11696.57.128.0/1796.57.128.1 to 96.57.255.25496.57.255.25532,766
11796.58.0.0/1796.58.0.1 to 96.58.127.25496.58.127.25532,766
11896.58.128.0/1796.58.128.1 to 96.58.255.25496.58.255.25532,766
11996.59.0.0/1796.59.0.1 to 96.59.127.25496.59.127.25532,766
12096.59.128.0/1796.59.128.1 to 96.59.255.25496.59.255.25532,766
12196.60.0.0/1796.60.0.1 to 96.60.127.25496.60.127.25532,766
12296.60.128.0/1796.60.128.1 to 96.60.255.25496.60.255.25532,766
12396.61.0.0/1796.61.0.1 to 96.61.127.25496.61.127.25532,766
12496.61.128.0/1796.61.128.1 to 96.61.255.25496.61.255.25532,766
12596.62.0.0/1796.62.0.1 to 96.62.127.25496.62.127.25532,766
12696.62.128.0/1796.62.128.1 to 96.62.255.25496.62.255.25532,766
12796.63.0.0/1796.63.0.1 to 96.63.127.25496.63.127.25532,766
12896.63.128.0/1796.63.128.1 to 96.63.255.25496.63.255.25532,766
12996.64.0.0/1796.64.0.1 to 96.64.127.25496.64.127.25532,766
13096.64.128.0/1796.64.128.1 to 96.64.255.25496.64.255.25532,766
13196.65.0.0/1796.65.0.1 to 96.65.127.25496.65.127.25532,766
13296.65.128.0/1796.65.128.1 to 96.65.255.25496.65.255.25532,766
13396.66.0.0/1796.66.0.1 to 96.66.127.25496.66.127.25532,766
13496.66.128.0/1796.66.128.1 to 96.66.255.25496.66.255.25532,766
13596.67.0.0/1796.67.0.1 to 96.67.127.25496.67.127.25532,766
13696.67.128.0/1796.67.128.1 to 96.67.255.25496.67.255.25532,766
13796.68.0.0/1796.68.0.1 to 96.68.127.25496.68.127.25532,766
13896.68.128.0/1796.68.128.1 to 96.68.255.25496.68.255.25532,766
13996.69.0.0/1796.69.0.1 to 96.69.127.25496.69.127.25532,766
14096.69.128.0/1796.69.128.1 to 96.69.255.25496.69.255.25532,766
14196.70.0.0/1796.70.0.1 to 96.70.127.25496.70.127.25532,766
14296.70.128.0/1796.70.128.1 to 96.70.255.25496.70.255.25532,766
14396.71.0.0/1796.71.0.1 to 96.71.127.25496.71.127.25532,766
14496.71.128.0/1796.71.128.1 to 96.71.255.25496.71.255.25532,766
14596.72.0.0/1796.72.0.1 to 96.72.127.25496.72.127.25532,766
14696.72.128.0/1796.72.128.1 to 96.72.255.25496.72.255.25532,766
14796.73.0.0/1796.73.0.1 to 96.73.127.25496.73.127.25532,766
14896.73.128.0/1796.73.128.1 to 96.73.255.25496.73.255.25532,766
14996.74.0.0/1796.74.0.1 to 96.74.127.25496.74.127.25532,766
15096.74.128.0/1796.74.128.1 to 96.74.255.25496.74.255.25532,766
15196.75.0.0/1796.75.0.1 to 96.75.127.25496.75.127.25532,766
15296.75.128.0/1796.75.128.1 to 96.75.255.25496.75.255.25532,766
15396.76.0.0/1796.76.0.1 to 96.76.127.25496.76.127.25532,766
15496.76.128.0/1796.76.128.1 to 96.76.255.25496.76.255.25532,766
15596.77.0.0/1796.77.0.1 to 96.77.127.25496.77.127.25532,766
15696.77.128.0/1796.77.128.1 to 96.77.255.25496.77.255.25532,766
15796.78.0.0/1796.78.0.1 to 96.78.127.25496.78.127.25532,766
15896.78.128.0/1796.78.128.1 to 96.78.255.25496.78.255.25532,766
15996.79.0.0/1796.79.0.1 to 96.79.127.25496.79.127.25532,766
16096.79.128.0/1796.79.128.1 to 96.79.255.25496.79.255.25532,766
16196.80.0.0/1796.80.0.1 to 96.80.127.25496.80.127.25532,766
16296.80.128.0/1796.80.128.1 to 96.80.255.25496.80.255.25532,766
16396.81.0.0/1796.81.0.1 to 96.81.127.25496.81.127.25532,766
16496.81.128.0/1796.81.128.1 to 96.81.255.25496.81.255.25532,766
16596.82.0.0/1796.82.0.1 to 96.82.127.25496.82.127.25532,766
16696.82.128.0/1796.82.128.1 to 96.82.255.25496.82.255.25532,766
16796.83.0.0/1796.83.0.1 to 96.83.127.25496.83.127.25532,766
16896.83.128.0/1796.83.128.1 to 96.83.255.25496.83.255.25532,766
16996.84.0.0/1796.84.0.1 to 96.84.127.25496.84.127.25532,766
17096.84.128.0/1796.84.128.1 to 96.84.255.25496.84.255.25532,766
17196.85.0.0/1796.85.0.1 to 96.85.127.25496.85.127.25532,766
17296.85.128.0/1796.85.128.1 to 96.85.255.25496.85.255.25532,766
17396.86.0.0/1796.86.0.1 to 96.86.127.25496.86.127.25532,766
17496.86.128.0/1796.86.128.1 to 96.86.255.25496.86.255.25532,766
17596.87.0.0/1796.87.0.1 to 96.87.127.25496.87.127.25532,766
17696.87.128.0/1796.87.128.1 to 96.87.255.25496.87.255.25532,766
17796.88.0.0/1796.88.0.1 to 96.88.127.25496.88.127.25532,766
17896.88.128.0/1796.88.128.1 to 96.88.255.25496.88.255.25532,766
17996.89.0.0/1796.89.0.1 to 96.89.127.25496.89.127.25532,766
18096.89.128.0/1796.89.128.1 to 96.89.255.25496.89.255.25532,766
18196.90.0.0/1796.90.0.1 to 96.90.127.25496.90.127.25532,766
18296.90.128.0/1796.90.128.1 to 96.90.255.25496.90.255.25532,766
18396.91.0.0/1796.91.0.1 to 96.91.127.25496.91.127.25532,766
18496.91.128.0/1796.91.128.1 to 96.91.255.25496.91.255.25532,766
18596.92.0.0/1796.92.0.1 to 96.92.127.25496.92.127.25532,766
18696.92.128.0/1796.92.128.1 to 96.92.255.25496.92.255.25532,766
18796.93.0.0/1796.93.0.1 to 96.93.127.25496.93.127.25532,766
18896.93.128.0/1796.93.128.1 to 96.93.255.25496.93.255.25532,766
18996.94.0.0/1796.94.0.1 to 96.94.127.25496.94.127.25532,766
19096.94.128.0/1796.94.128.1 to 96.94.255.25496.94.255.25532,766
19196.95.0.0/1796.95.0.1 to 96.95.127.25496.95.127.25532,766
19296.95.128.0/1796.95.128.1 to 96.95.255.25496.95.255.25532,766
19396.96.0.0/1796.96.0.1 to 96.96.127.25496.96.127.25532,766
19496.96.128.0/1796.96.128.1 to 96.96.255.25496.96.255.25532,766
19596.97.0.0/1796.97.0.1 to 96.97.127.25496.97.127.25532,766
19696.97.128.0/1796.97.128.1 to 96.97.255.25496.97.255.25532,766
19796.98.0.0/1796.98.0.1 to 96.98.127.25496.98.127.25532,766
19896.98.128.0/1796.98.128.1 to 96.98.255.25496.98.255.25532,766
19996.99.0.0/1796.99.0.1 to 96.99.127.25496.99.127.25532,766
20096.99.128.0/1796.99.128.1 to 96.99.255.25496.99.255.25532,766
20196.100.0.0/1796.100.0.1 to 96.100.127.25496.100.127.25532,766
20296.100.128.0/1796.100.128.1 to 96.100.255.25496.100.255.25532,766
20396.101.0.0/1796.101.0.1 to 96.101.127.25496.101.127.25532,766
20496.101.128.0/1796.101.128.1 to 96.101.255.25496.101.255.25532,766
20596.102.0.0/1796.102.0.1 to 96.102.127.25496.102.127.25532,766
20696.102.128.0/1796.102.128.1 to 96.102.255.25496.102.255.25532,766
20796.103.0.0/1796.103.0.1 to 96.103.127.25496.103.127.25532,766
20896.103.128.0/1796.103.128.1 to 96.103.255.25496.103.255.25532,766
20996.104.0.0/1796.104.0.1 to 96.104.127.25496.104.127.25532,766
21096.104.128.0/1796.104.128.1 to 96.104.255.25496.104.255.25532,766
21196.105.0.0/1796.105.0.1 to 96.105.127.25496.105.127.25532,766
21296.105.128.0/1796.105.128.1 to 96.105.255.25496.105.255.25532,766
21396.106.0.0/1796.106.0.1 to 96.106.127.25496.106.127.25532,766
21496.106.128.0/1796.106.128.1 to 96.106.255.25496.106.255.25532,766
21596.107.0.0/1796.107.0.1 to 96.107.127.25496.107.127.25532,766
21696.107.128.0/1796.107.128.1 to 96.107.255.25496.107.255.25532,766
21796.108.0.0/1796.108.0.1 to 96.108.127.25496.108.127.25532,766
21896.108.128.0/1796.108.128.1 to 96.108.255.25496.108.255.25532,766
21996.109.0.0/1796.109.0.1 to 96.109.127.25496.109.127.25532,766
22096.109.128.0/1796.109.128.1 to 96.109.255.25496.109.255.25532,766
22196.110.0.0/1796.110.0.1 to 96.110.127.25496.110.127.25532,766
22296.110.128.0/1796.110.128.1 to 96.110.255.25496.110.255.25532,766
22396.111.0.0/1796.111.0.1 to 96.111.127.25496.111.127.25532,766
22496.111.128.0/1796.111.128.1 to 96.111.255.25496.111.255.25532,766
22596.112.0.0/1796.112.0.1 to 96.112.127.25496.112.127.25532,766
22696.112.128.0/1796.112.128.1 to 96.112.255.25496.112.255.25532,766
22796.113.0.0/1796.113.0.1 to 96.113.127.25496.113.127.25532,766
22896.113.128.0/1796.113.128.1 to 96.113.255.25496.113.255.25532,766
22996.114.0.0/1796.114.0.1 to 96.114.127.25496.114.127.25532,766
23096.114.128.0/1796.114.128.1 to 96.114.255.25496.114.255.25532,766
23196.115.0.0/1796.115.0.1 to 96.115.127.25496.115.127.25532,766
23296.115.128.0/1796.115.128.1 to 96.115.255.25496.115.255.25532,766
23396.116.0.0/1796.116.0.1 to 96.116.127.25496.116.127.25532,766
23496.116.128.0/1796.116.128.1 to 96.116.255.25496.116.255.25532,766
23596.117.0.0/1796.117.0.1 to 96.117.127.25496.117.127.25532,766
23696.117.128.0/1796.117.128.1 to 96.117.255.25496.117.255.25532,766
23796.118.0.0/1796.118.0.1 to 96.118.127.25496.118.127.25532,766
23896.118.128.0/1796.118.128.1 to 96.118.255.25496.118.255.25532,766
23996.119.0.0/1796.119.0.1 to 96.119.127.25496.119.127.25532,766
24096.119.128.0/1796.119.128.1 to 96.119.255.25496.119.255.25532,766
24196.120.0.0/1796.120.0.1 to 96.120.127.25496.120.127.25532,766
24296.120.128.0/1796.120.128.1 to 96.120.255.25496.120.255.25532,766
24396.121.0.0/1796.121.0.1 to 96.121.127.25496.121.127.25532,766
24496.121.128.0/1796.121.128.1 to 96.121.255.25496.121.255.25532,766
24596.122.0.0/1796.122.0.1 to 96.122.127.25496.122.127.25532,766
24696.122.128.0/1796.122.128.1 to 96.122.255.25496.122.255.25532,766
24796.123.0.0/1796.123.0.1 to 96.123.127.25496.123.127.25532,766
24896.123.128.0/1796.123.128.1 to 96.123.255.25496.123.255.25532,766
24996.124.0.0/1796.124.0.1 to 96.124.127.25496.124.127.25532,766
25096.124.128.0/1796.124.128.1 to 96.124.255.25496.124.255.25532,766
25196.125.0.0/1796.125.0.1 to 96.125.127.25496.125.127.25532,766
25296.125.128.0/1796.125.128.1 to 96.125.255.25496.125.255.25532,766
25396.126.0.0/1796.126.0.1 to 96.126.127.25496.126.127.25532,766
25496.126.128.0/1796.126.128.1 to 96.126.255.25496.126.255.25532,766
25596.127.0.0/1796.127.0.1 to 96.127.127.25496.127.127.25532,766
25696.127.128.0/1796.127.128.1 to 96.127.255.25496.127.255.25532,766

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.