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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.

Network92.1.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
92.1.0.0
Broadcast address
92.1.255.255
First usable
92.1.0.1
Last usable
92.1.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 5C010000 · Integer 1543569408 to 1543634943
Reverse DNS zone
1.92.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011100.00000001..00000000.0000000092.1.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01011100.00000001..00000000.0000000092.1.0.0
Broadcast01011100.00000001..11111111.1111111192.1.255.255
Split into smaller subnets/26
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

92.1.0.0/16 makes 1,024 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
192.1.0.0/2692.1.0.1 to 92.1.0.6292.1.0.6362
292.1.0.64/2692.1.0.65 to 92.1.0.12692.1.0.12762
392.1.0.128/2692.1.0.129 to 92.1.0.19092.1.0.19162
492.1.0.192/2692.1.0.193 to 92.1.0.25492.1.0.25562
592.1.1.0/2692.1.1.1 to 92.1.1.6292.1.1.6362
692.1.1.64/2692.1.1.65 to 92.1.1.12692.1.1.12762
792.1.1.128/2692.1.1.129 to 92.1.1.19092.1.1.19162
892.1.1.192/2692.1.1.193 to 92.1.1.25492.1.1.25562
992.1.2.0/2692.1.2.1 to 92.1.2.6292.1.2.6362
1092.1.2.64/2692.1.2.65 to 92.1.2.12692.1.2.12762
1192.1.2.128/2692.1.2.129 to 92.1.2.19092.1.2.19162
1292.1.2.192/2692.1.2.193 to 92.1.2.25492.1.2.25562
1392.1.3.0/2692.1.3.1 to 92.1.3.6292.1.3.6362
1492.1.3.64/2692.1.3.65 to 92.1.3.12692.1.3.12762
1592.1.3.128/2692.1.3.129 to 92.1.3.19092.1.3.19162
1692.1.3.192/2692.1.3.193 to 92.1.3.25492.1.3.25562
1792.1.4.0/2692.1.4.1 to 92.1.4.6292.1.4.6362
1892.1.4.64/2692.1.4.65 to 92.1.4.12692.1.4.12762
1992.1.4.128/2692.1.4.129 to 92.1.4.19092.1.4.19162
2092.1.4.192/2692.1.4.193 to 92.1.4.25492.1.4.25562
2192.1.5.0/2692.1.5.1 to 92.1.5.6292.1.5.6362
2292.1.5.64/2692.1.5.65 to 92.1.5.12692.1.5.12762
2392.1.5.128/2692.1.5.129 to 92.1.5.19092.1.5.19162
2492.1.5.192/2692.1.5.193 to 92.1.5.25492.1.5.25562
2592.1.6.0/2692.1.6.1 to 92.1.6.6292.1.6.6362
2692.1.6.64/2692.1.6.65 to 92.1.6.12692.1.6.12762
2792.1.6.128/2692.1.6.129 to 92.1.6.19092.1.6.19162
2892.1.6.192/2692.1.6.193 to 92.1.6.25492.1.6.25562
2992.1.7.0/2692.1.7.1 to 92.1.7.6292.1.7.6362
3092.1.7.64/2692.1.7.65 to 92.1.7.12692.1.7.12762
3192.1.7.128/2692.1.7.129 to 92.1.7.19092.1.7.19162
3292.1.7.192/2692.1.7.193 to 92.1.7.25492.1.7.25562
3392.1.8.0/2692.1.8.1 to 92.1.8.6292.1.8.6362
3492.1.8.64/2692.1.8.65 to 92.1.8.12692.1.8.12762
3592.1.8.128/2692.1.8.129 to 92.1.8.19092.1.8.19162
3692.1.8.192/2692.1.8.193 to 92.1.8.25492.1.8.25562
3792.1.9.0/2692.1.9.1 to 92.1.9.6292.1.9.6362
3892.1.9.64/2692.1.9.65 to 92.1.9.12692.1.9.12762
3992.1.9.128/2692.1.9.129 to 92.1.9.19092.1.9.19162
4092.1.9.192/2692.1.9.193 to 92.1.9.25492.1.9.25562
4192.1.10.0/2692.1.10.1 to 92.1.10.6292.1.10.6362
4292.1.10.64/2692.1.10.65 to 92.1.10.12692.1.10.12762
4392.1.10.128/2692.1.10.129 to 92.1.10.19092.1.10.19162
4492.1.10.192/2692.1.10.193 to 92.1.10.25492.1.10.25562
4592.1.11.0/2692.1.11.1 to 92.1.11.6292.1.11.6362
4692.1.11.64/2692.1.11.65 to 92.1.11.12692.1.11.12762
4792.1.11.128/2692.1.11.129 to 92.1.11.19092.1.11.19162
4892.1.11.192/2692.1.11.193 to 92.1.11.25492.1.11.25562
4992.1.12.0/2692.1.12.1 to 92.1.12.6292.1.12.6362
5092.1.12.64/2692.1.12.65 to 92.1.12.12692.1.12.12762
5192.1.12.128/2692.1.12.129 to 92.1.12.19092.1.12.19162
5292.1.12.192/2692.1.12.193 to 92.1.12.25492.1.12.25562
5392.1.13.0/2692.1.13.1 to 92.1.13.6292.1.13.6362
5492.1.13.64/2692.1.13.65 to 92.1.13.12692.1.13.12762
5592.1.13.128/2692.1.13.129 to 92.1.13.19092.1.13.19162
5692.1.13.192/2692.1.13.193 to 92.1.13.25492.1.13.25562
5792.1.14.0/2692.1.14.1 to 92.1.14.6292.1.14.6362
5892.1.14.64/2692.1.14.65 to 92.1.14.12692.1.14.12762
5992.1.14.128/2692.1.14.129 to 92.1.14.19092.1.14.19162
6092.1.14.192/2692.1.14.193 to 92.1.14.25492.1.14.25562
6192.1.15.0/2692.1.15.1 to 92.1.15.6292.1.15.6362
6292.1.15.64/2692.1.15.65 to 92.1.15.12692.1.15.12762
6392.1.15.128/2692.1.15.129 to 92.1.15.19092.1.15.19162
6492.1.15.192/2692.1.15.193 to 92.1.15.25492.1.15.25562
6592.1.16.0/2692.1.16.1 to 92.1.16.6292.1.16.6362
6692.1.16.64/2692.1.16.65 to 92.1.16.12692.1.16.12762
6792.1.16.128/2692.1.16.129 to 92.1.16.19092.1.16.19162
6892.1.16.192/2692.1.16.193 to 92.1.16.25492.1.16.25562
6992.1.17.0/2692.1.17.1 to 92.1.17.6292.1.17.6362
7092.1.17.64/2692.1.17.65 to 92.1.17.12692.1.17.12762
7192.1.17.128/2692.1.17.129 to 92.1.17.19092.1.17.19162
7292.1.17.192/2692.1.17.193 to 92.1.17.25492.1.17.25562
7392.1.18.0/2692.1.18.1 to 92.1.18.6292.1.18.6362
7492.1.18.64/2692.1.18.65 to 92.1.18.12692.1.18.12762
7592.1.18.128/2692.1.18.129 to 92.1.18.19092.1.18.19162
7692.1.18.192/2692.1.18.193 to 92.1.18.25492.1.18.25562
7792.1.19.0/2692.1.19.1 to 92.1.19.6292.1.19.6362
7892.1.19.64/2692.1.19.65 to 92.1.19.12692.1.19.12762
7992.1.19.128/2692.1.19.129 to 92.1.19.19092.1.19.19162
8092.1.19.192/2692.1.19.193 to 92.1.19.25492.1.19.25562
8192.1.20.0/2692.1.20.1 to 92.1.20.6292.1.20.6362
8292.1.20.64/2692.1.20.65 to 92.1.20.12692.1.20.12762
8392.1.20.128/2692.1.20.129 to 92.1.20.19092.1.20.19162
8492.1.20.192/2692.1.20.193 to 92.1.20.25492.1.20.25562
8592.1.21.0/2692.1.21.1 to 92.1.21.6292.1.21.6362
8692.1.21.64/2692.1.21.65 to 92.1.21.12692.1.21.12762
8792.1.21.128/2692.1.21.129 to 92.1.21.19092.1.21.19162
8892.1.21.192/2692.1.21.193 to 92.1.21.25492.1.21.25562
8992.1.22.0/2692.1.22.1 to 92.1.22.6292.1.22.6362
9092.1.22.64/2692.1.22.65 to 92.1.22.12692.1.22.12762
9192.1.22.128/2692.1.22.129 to 92.1.22.19092.1.22.19162
9292.1.22.192/2692.1.22.193 to 92.1.22.25492.1.22.25562
9392.1.23.0/2692.1.23.1 to 92.1.23.6292.1.23.6362
9492.1.23.64/2692.1.23.65 to 92.1.23.12692.1.23.12762
9592.1.23.128/2692.1.23.129 to 92.1.23.19092.1.23.19162
9692.1.23.192/2692.1.23.193 to 92.1.23.25492.1.23.25562
9792.1.24.0/2692.1.24.1 to 92.1.24.6292.1.24.6362
9892.1.24.64/2692.1.24.65 to 92.1.24.12692.1.24.12762
9992.1.24.128/2692.1.24.129 to 92.1.24.19092.1.24.19162
10092.1.24.192/2692.1.24.193 to 92.1.24.25492.1.24.25562
10192.1.25.0/2692.1.25.1 to 92.1.25.6292.1.25.6362
10292.1.25.64/2692.1.25.65 to 92.1.25.12692.1.25.12762
10392.1.25.128/2692.1.25.129 to 92.1.25.19092.1.25.19162
10492.1.25.192/2692.1.25.193 to 92.1.25.25492.1.25.25562
10592.1.26.0/2692.1.26.1 to 92.1.26.6292.1.26.6362
10692.1.26.64/2692.1.26.65 to 92.1.26.12692.1.26.12762
10792.1.26.128/2692.1.26.129 to 92.1.26.19092.1.26.19162
10892.1.26.192/2692.1.26.193 to 92.1.26.25492.1.26.25562
10992.1.27.0/2692.1.27.1 to 92.1.27.6292.1.27.6362
11092.1.27.64/2692.1.27.65 to 92.1.27.12692.1.27.12762
11192.1.27.128/2692.1.27.129 to 92.1.27.19092.1.27.19162
11292.1.27.192/2692.1.27.193 to 92.1.27.25492.1.27.25562
11392.1.28.0/2692.1.28.1 to 92.1.28.6292.1.28.6362
11492.1.28.64/2692.1.28.65 to 92.1.28.12692.1.28.12762
11592.1.28.128/2692.1.28.129 to 92.1.28.19092.1.28.19162
11692.1.28.192/2692.1.28.193 to 92.1.28.25492.1.28.25562
11792.1.29.0/2692.1.29.1 to 92.1.29.6292.1.29.6362
11892.1.29.64/2692.1.29.65 to 92.1.29.12692.1.29.12762
11992.1.29.128/2692.1.29.129 to 92.1.29.19092.1.29.19162
12092.1.29.192/2692.1.29.193 to 92.1.29.25492.1.29.25562
12192.1.30.0/2692.1.30.1 to 92.1.30.6292.1.30.6362
12292.1.30.64/2692.1.30.65 to 92.1.30.12692.1.30.12762
12392.1.30.128/2692.1.30.129 to 92.1.30.19092.1.30.19162
12492.1.30.192/2692.1.30.193 to 92.1.30.25492.1.30.25562
12592.1.31.0/2692.1.31.1 to 92.1.31.6292.1.31.6362
12692.1.31.64/2692.1.31.65 to 92.1.31.12692.1.31.12762
12792.1.31.128/2692.1.31.129 to 92.1.31.19092.1.31.19162
12892.1.31.192/2692.1.31.193 to 92.1.31.25492.1.31.25562
12992.1.32.0/2692.1.32.1 to 92.1.32.6292.1.32.6362
13092.1.32.64/2692.1.32.65 to 92.1.32.12692.1.32.12762
13192.1.32.128/2692.1.32.129 to 92.1.32.19092.1.32.19162
13292.1.32.192/2692.1.32.193 to 92.1.32.25492.1.32.25562
13392.1.33.0/2692.1.33.1 to 92.1.33.6292.1.33.6362
13492.1.33.64/2692.1.33.65 to 92.1.33.12692.1.33.12762
13592.1.33.128/2692.1.33.129 to 92.1.33.19092.1.33.19162
13692.1.33.192/2692.1.33.193 to 92.1.33.25492.1.33.25562
13792.1.34.0/2692.1.34.1 to 92.1.34.6292.1.34.6362
13892.1.34.64/2692.1.34.65 to 92.1.34.12692.1.34.12762
13992.1.34.128/2692.1.34.129 to 92.1.34.19092.1.34.19162
14092.1.34.192/2692.1.34.193 to 92.1.34.25492.1.34.25562
14192.1.35.0/2692.1.35.1 to 92.1.35.6292.1.35.6362
14292.1.35.64/2692.1.35.65 to 92.1.35.12692.1.35.12762
14392.1.35.128/2692.1.35.129 to 92.1.35.19092.1.35.19162
14492.1.35.192/2692.1.35.193 to 92.1.35.25492.1.35.25562
14592.1.36.0/2692.1.36.1 to 92.1.36.6292.1.36.6362
14692.1.36.64/2692.1.36.65 to 92.1.36.12692.1.36.12762
14792.1.36.128/2692.1.36.129 to 92.1.36.19092.1.36.19162
14892.1.36.192/2692.1.36.193 to 92.1.36.25492.1.36.25562
14992.1.37.0/2692.1.37.1 to 92.1.37.6292.1.37.6362
15092.1.37.64/2692.1.37.65 to 92.1.37.12692.1.37.12762
15192.1.37.128/2692.1.37.129 to 92.1.37.19092.1.37.19162
15292.1.37.192/2692.1.37.193 to 92.1.37.25492.1.37.25562
15392.1.38.0/2692.1.38.1 to 92.1.38.6292.1.38.6362
15492.1.38.64/2692.1.38.65 to 92.1.38.12692.1.38.12762
15592.1.38.128/2692.1.38.129 to 92.1.38.19092.1.38.19162
15692.1.38.192/2692.1.38.193 to 92.1.38.25492.1.38.25562
15792.1.39.0/2692.1.39.1 to 92.1.39.6292.1.39.6362
15892.1.39.64/2692.1.39.65 to 92.1.39.12692.1.39.12762
15992.1.39.128/2692.1.39.129 to 92.1.39.19092.1.39.19162
16092.1.39.192/2692.1.39.193 to 92.1.39.25492.1.39.25562
16192.1.40.0/2692.1.40.1 to 92.1.40.6292.1.40.6362
16292.1.40.64/2692.1.40.65 to 92.1.40.12692.1.40.12762
16392.1.40.128/2692.1.40.129 to 92.1.40.19092.1.40.19162
16492.1.40.192/2692.1.40.193 to 92.1.40.25492.1.40.25562
16592.1.41.0/2692.1.41.1 to 92.1.41.6292.1.41.6362
16692.1.41.64/2692.1.41.65 to 92.1.41.12692.1.41.12762
16792.1.41.128/2692.1.41.129 to 92.1.41.19092.1.41.19162
16892.1.41.192/2692.1.41.193 to 92.1.41.25492.1.41.25562
16992.1.42.0/2692.1.42.1 to 92.1.42.6292.1.42.6362
17092.1.42.64/2692.1.42.65 to 92.1.42.12692.1.42.12762
17192.1.42.128/2692.1.42.129 to 92.1.42.19092.1.42.19162
17292.1.42.192/2692.1.42.193 to 92.1.42.25492.1.42.25562
17392.1.43.0/2692.1.43.1 to 92.1.43.6292.1.43.6362
17492.1.43.64/2692.1.43.65 to 92.1.43.12692.1.43.12762
17592.1.43.128/2692.1.43.129 to 92.1.43.19092.1.43.19162
17692.1.43.192/2692.1.43.193 to 92.1.43.25492.1.43.25562
17792.1.44.0/2692.1.44.1 to 92.1.44.6292.1.44.6362
17892.1.44.64/2692.1.44.65 to 92.1.44.12692.1.44.12762
17992.1.44.128/2692.1.44.129 to 92.1.44.19092.1.44.19162
18092.1.44.192/2692.1.44.193 to 92.1.44.25492.1.44.25562
18192.1.45.0/2692.1.45.1 to 92.1.45.6292.1.45.6362
18292.1.45.64/2692.1.45.65 to 92.1.45.12692.1.45.12762
18392.1.45.128/2692.1.45.129 to 92.1.45.19092.1.45.19162
18492.1.45.192/2692.1.45.193 to 92.1.45.25492.1.45.25562
18592.1.46.0/2692.1.46.1 to 92.1.46.6292.1.46.6362
18692.1.46.64/2692.1.46.65 to 92.1.46.12692.1.46.12762
18792.1.46.128/2692.1.46.129 to 92.1.46.19092.1.46.19162
18892.1.46.192/2692.1.46.193 to 92.1.46.25492.1.46.25562
18992.1.47.0/2692.1.47.1 to 92.1.47.6292.1.47.6362
19092.1.47.64/2692.1.47.65 to 92.1.47.12692.1.47.12762
19192.1.47.128/2692.1.47.129 to 92.1.47.19092.1.47.19162
19292.1.47.192/2692.1.47.193 to 92.1.47.25492.1.47.25562
19392.1.48.0/2692.1.48.1 to 92.1.48.6292.1.48.6362
19492.1.48.64/2692.1.48.65 to 92.1.48.12692.1.48.12762
19592.1.48.128/2692.1.48.129 to 92.1.48.19092.1.48.19162
19692.1.48.192/2692.1.48.193 to 92.1.48.25492.1.48.25562
19792.1.49.0/2692.1.49.1 to 92.1.49.6292.1.49.6362
19892.1.49.64/2692.1.49.65 to 92.1.49.12692.1.49.12762
19992.1.49.128/2692.1.49.129 to 92.1.49.19092.1.49.19162
20092.1.49.192/2692.1.49.193 to 92.1.49.25492.1.49.25562
20192.1.50.0/2692.1.50.1 to 92.1.50.6292.1.50.6362
20292.1.50.64/2692.1.50.65 to 92.1.50.12692.1.50.12762
20392.1.50.128/2692.1.50.129 to 92.1.50.19092.1.50.19162
20492.1.50.192/2692.1.50.193 to 92.1.50.25492.1.50.25562
20592.1.51.0/2692.1.51.1 to 92.1.51.6292.1.51.6362
20692.1.51.64/2692.1.51.65 to 92.1.51.12692.1.51.12762
20792.1.51.128/2692.1.51.129 to 92.1.51.19092.1.51.19162
20892.1.51.192/2692.1.51.193 to 92.1.51.25492.1.51.25562
20992.1.52.0/2692.1.52.1 to 92.1.52.6292.1.52.6362
21092.1.52.64/2692.1.52.65 to 92.1.52.12692.1.52.12762
21192.1.52.128/2692.1.52.129 to 92.1.52.19092.1.52.19162
21292.1.52.192/2692.1.52.193 to 92.1.52.25492.1.52.25562
21392.1.53.0/2692.1.53.1 to 92.1.53.6292.1.53.6362
21492.1.53.64/2692.1.53.65 to 92.1.53.12692.1.53.12762
21592.1.53.128/2692.1.53.129 to 92.1.53.19092.1.53.19162
21692.1.53.192/2692.1.53.193 to 92.1.53.25492.1.53.25562
21792.1.54.0/2692.1.54.1 to 92.1.54.6292.1.54.6362
21892.1.54.64/2692.1.54.65 to 92.1.54.12692.1.54.12762
21992.1.54.128/2692.1.54.129 to 92.1.54.19092.1.54.19162
22092.1.54.192/2692.1.54.193 to 92.1.54.25492.1.54.25562
22192.1.55.0/2692.1.55.1 to 92.1.55.6292.1.55.6362
22292.1.55.64/2692.1.55.65 to 92.1.55.12692.1.55.12762
22392.1.55.128/2692.1.55.129 to 92.1.55.19092.1.55.19162
22492.1.55.192/2692.1.55.193 to 92.1.55.25492.1.55.25562
22592.1.56.0/2692.1.56.1 to 92.1.56.6292.1.56.6362
22692.1.56.64/2692.1.56.65 to 92.1.56.12692.1.56.12762
22792.1.56.128/2692.1.56.129 to 92.1.56.19092.1.56.19162
22892.1.56.192/2692.1.56.193 to 92.1.56.25492.1.56.25562
22992.1.57.0/2692.1.57.1 to 92.1.57.6292.1.57.6362
23092.1.57.64/2692.1.57.65 to 92.1.57.12692.1.57.12762
23192.1.57.128/2692.1.57.129 to 92.1.57.19092.1.57.19162
23292.1.57.192/2692.1.57.193 to 92.1.57.25492.1.57.25562
23392.1.58.0/2692.1.58.1 to 92.1.58.6292.1.58.6362
23492.1.58.64/2692.1.58.65 to 92.1.58.12692.1.58.12762
23592.1.58.128/2692.1.58.129 to 92.1.58.19092.1.58.19162
23692.1.58.192/2692.1.58.193 to 92.1.58.25492.1.58.25562
23792.1.59.0/2692.1.59.1 to 92.1.59.6292.1.59.6362
23892.1.59.64/2692.1.59.65 to 92.1.59.12692.1.59.12762
23992.1.59.128/2692.1.59.129 to 92.1.59.19092.1.59.19162
24092.1.59.192/2692.1.59.193 to 92.1.59.25492.1.59.25562
24192.1.60.0/2692.1.60.1 to 92.1.60.6292.1.60.6362
24292.1.60.64/2692.1.60.65 to 92.1.60.12692.1.60.12762
24392.1.60.128/2692.1.60.129 to 92.1.60.19092.1.60.19162
24492.1.60.192/2692.1.60.193 to 92.1.60.25492.1.60.25562
24592.1.61.0/2692.1.61.1 to 92.1.61.6292.1.61.6362
24692.1.61.64/2692.1.61.65 to 92.1.61.12692.1.61.12762
24792.1.61.128/2692.1.61.129 to 92.1.61.19092.1.61.19162
24892.1.61.192/2692.1.61.193 to 92.1.61.25492.1.61.25562
24992.1.62.0/2692.1.62.1 to 92.1.62.6292.1.62.6362
25092.1.62.64/2692.1.62.65 to 92.1.62.12692.1.62.12762
25192.1.62.128/2692.1.62.129 to 92.1.62.19092.1.62.19162
25292.1.62.192/2692.1.62.193 to 92.1.62.25492.1.62.25562
25392.1.63.0/2692.1.63.1 to 92.1.63.6292.1.63.6362
25492.1.63.64/2692.1.63.65 to 92.1.63.12692.1.63.12762
25592.1.63.128/2692.1.63.129 to 92.1.63.19092.1.63.19162
25692.1.63.192/2692.1.63.193 to 92.1.63.25492.1.63.25562

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.