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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.

Network22.93.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
22.93.0.0
Broadcast address
22.93.127.255
First usable
22.93.0.1
Last usable
22.93.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Public public
Old class
A (default /8)
As numbers
Hex 165D0000 · Integer 375193600 to 375226367
Reverse DNS zones
0.93.22.in-addr.arpa
1.93.22.in-addr.arpa
2.93.22.in-addr.arpa
3.93.22.in-addr.arpa
4.93.22.in-addr.arpa
5.93.22.in-addr.arpa
6.93.22.in-addr.arpa
7.93.22.in-addr.arpa
8.93.22.in-addr.arpa
9.93.22.in-addr.arpa
10.93.22.in-addr.arpa
11.93.22.in-addr.arpa
12.93.22.in-addr.arpa
13.93.22.in-addr.arpa
14.93.22.in-addr.arpa
15.93.22.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00010110.01011101.00000000.0000000022.93.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network00010110.01011101.00000000.0000000022.93.0.0
Broadcast00010110.01011101.01111111.1111111122.93.127.255
Split into smaller subnets/26
/18 (2)/19 (4)/20 (8)/21 (16)/22 (32)/23 (64)/24 (128)/25 (256)/26 (512)/27 (1,024)/28 (2,048)/29 (4,096)

22.93.0.0/17 makes 512 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
122.93.0.0/2622.93.0.1 to 22.93.0.6222.93.0.6362
222.93.0.64/2622.93.0.65 to 22.93.0.12622.93.0.12762
322.93.0.128/2622.93.0.129 to 22.93.0.19022.93.0.19162
422.93.0.192/2622.93.0.193 to 22.93.0.25422.93.0.25562
522.93.1.0/2622.93.1.1 to 22.93.1.6222.93.1.6362
622.93.1.64/2622.93.1.65 to 22.93.1.12622.93.1.12762
722.93.1.128/2622.93.1.129 to 22.93.1.19022.93.1.19162
822.93.1.192/2622.93.1.193 to 22.93.1.25422.93.1.25562
922.93.2.0/2622.93.2.1 to 22.93.2.6222.93.2.6362
1022.93.2.64/2622.93.2.65 to 22.93.2.12622.93.2.12762
1122.93.2.128/2622.93.2.129 to 22.93.2.19022.93.2.19162
1222.93.2.192/2622.93.2.193 to 22.93.2.25422.93.2.25562
1322.93.3.0/2622.93.3.1 to 22.93.3.6222.93.3.6362
1422.93.3.64/2622.93.3.65 to 22.93.3.12622.93.3.12762
1522.93.3.128/2622.93.3.129 to 22.93.3.19022.93.3.19162
1622.93.3.192/2622.93.3.193 to 22.93.3.25422.93.3.25562
1722.93.4.0/2622.93.4.1 to 22.93.4.6222.93.4.6362
1822.93.4.64/2622.93.4.65 to 22.93.4.12622.93.4.12762
1922.93.4.128/2622.93.4.129 to 22.93.4.19022.93.4.19162
2022.93.4.192/2622.93.4.193 to 22.93.4.25422.93.4.25562
2122.93.5.0/2622.93.5.1 to 22.93.5.6222.93.5.6362
2222.93.5.64/2622.93.5.65 to 22.93.5.12622.93.5.12762
2322.93.5.128/2622.93.5.129 to 22.93.5.19022.93.5.19162
2422.93.5.192/2622.93.5.193 to 22.93.5.25422.93.5.25562
2522.93.6.0/2622.93.6.1 to 22.93.6.6222.93.6.6362
2622.93.6.64/2622.93.6.65 to 22.93.6.12622.93.6.12762
2722.93.6.128/2622.93.6.129 to 22.93.6.19022.93.6.19162
2822.93.6.192/2622.93.6.193 to 22.93.6.25422.93.6.25562
2922.93.7.0/2622.93.7.1 to 22.93.7.6222.93.7.6362
3022.93.7.64/2622.93.7.65 to 22.93.7.12622.93.7.12762
3122.93.7.128/2622.93.7.129 to 22.93.7.19022.93.7.19162
3222.93.7.192/2622.93.7.193 to 22.93.7.25422.93.7.25562
3322.93.8.0/2622.93.8.1 to 22.93.8.6222.93.8.6362
3422.93.8.64/2622.93.8.65 to 22.93.8.12622.93.8.12762
3522.93.8.128/2622.93.8.129 to 22.93.8.19022.93.8.19162
3622.93.8.192/2622.93.8.193 to 22.93.8.25422.93.8.25562
3722.93.9.0/2622.93.9.1 to 22.93.9.6222.93.9.6362
3822.93.9.64/2622.93.9.65 to 22.93.9.12622.93.9.12762
3922.93.9.128/2622.93.9.129 to 22.93.9.19022.93.9.19162
4022.93.9.192/2622.93.9.193 to 22.93.9.25422.93.9.25562
4122.93.10.0/2622.93.10.1 to 22.93.10.6222.93.10.6362
4222.93.10.64/2622.93.10.65 to 22.93.10.12622.93.10.12762
4322.93.10.128/2622.93.10.129 to 22.93.10.19022.93.10.19162
4422.93.10.192/2622.93.10.193 to 22.93.10.25422.93.10.25562
4522.93.11.0/2622.93.11.1 to 22.93.11.6222.93.11.6362
4622.93.11.64/2622.93.11.65 to 22.93.11.12622.93.11.12762
4722.93.11.128/2622.93.11.129 to 22.93.11.19022.93.11.19162
4822.93.11.192/2622.93.11.193 to 22.93.11.25422.93.11.25562
4922.93.12.0/2622.93.12.1 to 22.93.12.6222.93.12.6362
5022.93.12.64/2622.93.12.65 to 22.93.12.12622.93.12.12762
5122.93.12.128/2622.93.12.129 to 22.93.12.19022.93.12.19162
5222.93.12.192/2622.93.12.193 to 22.93.12.25422.93.12.25562
5322.93.13.0/2622.93.13.1 to 22.93.13.6222.93.13.6362
5422.93.13.64/2622.93.13.65 to 22.93.13.12622.93.13.12762
5522.93.13.128/2622.93.13.129 to 22.93.13.19022.93.13.19162
5622.93.13.192/2622.93.13.193 to 22.93.13.25422.93.13.25562
5722.93.14.0/2622.93.14.1 to 22.93.14.6222.93.14.6362
5822.93.14.64/2622.93.14.65 to 22.93.14.12622.93.14.12762
5922.93.14.128/2622.93.14.129 to 22.93.14.19022.93.14.19162
6022.93.14.192/2622.93.14.193 to 22.93.14.25422.93.14.25562
6122.93.15.0/2622.93.15.1 to 22.93.15.6222.93.15.6362
6222.93.15.64/2622.93.15.65 to 22.93.15.12622.93.15.12762
6322.93.15.128/2622.93.15.129 to 22.93.15.19022.93.15.19162
6422.93.15.192/2622.93.15.193 to 22.93.15.25422.93.15.25562
6522.93.16.0/2622.93.16.1 to 22.93.16.6222.93.16.6362
6622.93.16.64/2622.93.16.65 to 22.93.16.12622.93.16.12762
6722.93.16.128/2622.93.16.129 to 22.93.16.19022.93.16.19162
6822.93.16.192/2622.93.16.193 to 22.93.16.25422.93.16.25562
6922.93.17.0/2622.93.17.1 to 22.93.17.6222.93.17.6362
7022.93.17.64/2622.93.17.65 to 22.93.17.12622.93.17.12762
7122.93.17.128/2622.93.17.129 to 22.93.17.19022.93.17.19162
7222.93.17.192/2622.93.17.193 to 22.93.17.25422.93.17.25562
7322.93.18.0/2622.93.18.1 to 22.93.18.6222.93.18.6362
7422.93.18.64/2622.93.18.65 to 22.93.18.12622.93.18.12762
7522.93.18.128/2622.93.18.129 to 22.93.18.19022.93.18.19162
7622.93.18.192/2622.93.18.193 to 22.93.18.25422.93.18.25562
7722.93.19.0/2622.93.19.1 to 22.93.19.6222.93.19.6362
7822.93.19.64/2622.93.19.65 to 22.93.19.12622.93.19.12762
7922.93.19.128/2622.93.19.129 to 22.93.19.19022.93.19.19162
8022.93.19.192/2622.93.19.193 to 22.93.19.25422.93.19.25562
8122.93.20.0/2622.93.20.1 to 22.93.20.6222.93.20.6362
8222.93.20.64/2622.93.20.65 to 22.93.20.12622.93.20.12762
8322.93.20.128/2622.93.20.129 to 22.93.20.19022.93.20.19162
8422.93.20.192/2622.93.20.193 to 22.93.20.25422.93.20.25562
8522.93.21.0/2622.93.21.1 to 22.93.21.6222.93.21.6362
8622.93.21.64/2622.93.21.65 to 22.93.21.12622.93.21.12762
8722.93.21.128/2622.93.21.129 to 22.93.21.19022.93.21.19162
8822.93.21.192/2622.93.21.193 to 22.93.21.25422.93.21.25562
8922.93.22.0/2622.93.22.1 to 22.93.22.6222.93.22.6362
9022.93.22.64/2622.93.22.65 to 22.93.22.12622.93.22.12762
9122.93.22.128/2622.93.22.129 to 22.93.22.19022.93.22.19162
9222.93.22.192/2622.93.22.193 to 22.93.22.25422.93.22.25562
9322.93.23.0/2622.93.23.1 to 22.93.23.6222.93.23.6362
9422.93.23.64/2622.93.23.65 to 22.93.23.12622.93.23.12762
9522.93.23.128/2622.93.23.129 to 22.93.23.19022.93.23.19162
9622.93.23.192/2622.93.23.193 to 22.93.23.25422.93.23.25562
9722.93.24.0/2622.93.24.1 to 22.93.24.6222.93.24.6362
9822.93.24.64/2622.93.24.65 to 22.93.24.12622.93.24.12762
9922.93.24.128/2622.93.24.129 to 22.93.24.19022.93.24.19162
10022.93.24.192/2622.93.24.193 to 22.93.24.25422.93.24.25562
10122.93.25.0/2622.93.25.1 to 22.93.25.6222.93.25.6362
10222.93.25.64/2622.93.25.65 to 22.93.25.12622.93.25.12762
10322.93.25.128/2622.93.25.129 to 22.93.25.19022.93.25.19162
10422.93.25.192/2622.93.25.193 to 22.93.25.25422.93.25.25562
10522.93.26.0/2622.93.26.1 to 22.93.26.6222.93.26.6362
10622.93.26.64/2622.93.26.65 to 22.93.26.12622.93.26.12762
10722.93.26.128/2622.93.26.129 to 22.93.26.19022.93.26.19162
10822.93.26.192/2622.93.26.193 to 22.93.26.25422.93.26.25562
10922.93.27.0/2622.93.27.1 to 22.93.27.6222.93.27.6362
11022.93.27.64/2622.93.27.65 to 22.93.27.12622.93.27.12762
11122.93.27.128/2622.93.27.129 to 22.93.27.19022.93.27.19162
11222.93.27.192/2622.93.27.193 to 22.93.27.25422.93.27.25562
11322.93.28.0/2622.93.28.1 to 22.93.28.6222.93.28.6362
11422.93.28.64/2622.93.28.65 to 22.93.28.12622.93.28.12762
11522.93.28.128/2622.93.28.129 to 22.93.28.19022.93.28.19162
11622.93.28.192/2622.93.28.193 to 22.93.28.25422.93.28.25562
11722.93.29.0/2622.93.29.1 to 22.93.29.6222.93.29.6362
11822.93.29.64/2622.93.29.65 to 22.93.29.12622.93.29.12762
11922.93.29.128/2622.93.29.129 to 22.93.29.19022.93.29.19162
12022.93.29.192/2622.93.29.193 to 22.93.29.25422.93.29.25562
12122.93.30.0/2622.93.30.1 to 22.93.30.6222.93.30.6362
12222.93.30.64/2622.93.30.65 to 22.93.30.12622.93.30.12762
12322.93.30.128/2622.93.30.129 to 22.93.30.19022.93.30.19162
12422.93.30.192/2622.93.30.193 to 22.93.30.25422.93.30.25562
12522.93.31.0/2622.93.31.1 to 22.93.31.6222.93.31.6362
12622.93.31.64/2622.93.31.65 to 22.93.31.12622.93.31.12762
12722.93.31.128/2622.93.31.129 to 22.93.31.19022.93.31.19162
12822.93.31.192/2622.93.31.193 to 22.93.31.25422.93.31.25562
12922.93.32.0/2622.93.32.1 to 22.93.32.6222.93.32.6362
13022.93.32.64/2622.93.32.65 to 22.93.32.12622.93.32.12762
13122.93.32.128/2622.93.32.129 to 22.93.32.19022.93.32.19162
13222.93.32.192/2622.93.32.193 to 22.93.32.25422.93.32.25562
13322.93.33.0/2622.93.33.1 to 22.93.33.6222.93.33.6362
13422.93.33.64/2622.93.33.65 to 22.93.33.12622.93.33.12762
13522.93.33.128/2622.93.33.129 to 22.93.33.19022.93.33.19162
13622.93.33.192/2622.93.33.193 to 22.93.33.25422.93.33.25562
13722.93.34.0/2622.93.34.1 to 22.93.34.6222.93.34.6362
13822.93.34.64/2622.93.34.65 to 22.93.34.12622.93.34.12762
13922.93.34.128/2622.93.34.129 to 22.93.34.19022.93.34.19162
14022.93.34.192/2622.93.34.193 to 22.93.34.25422.93.34.25562
14122.93.35.0/2622.93.35.1 to 22.93.35.6222.93.35.6362
14222.93.35.64/2622.93.35.65 to 22.93.35.12622.93.35.12762
14322.93.35.128/2622.93.35.129 to 22.93.35.19022.93.35.19162
14422.93.35.192/2622.93.35.193 to 22.93.35.25422.93.35.25562
14522.93.36.0/2622.93.36.1 to 22.93.36.6222.93.36.6362
14622.93.36.64/2622.93.36.65 to 22.93.36.12622.93.36.12762
14722.93.36.128/2622.93.36.129 to 22.93.36.19022.93.36.19162
14822.93.36.192/2622.93.36.193 to 22.93.36.25422.93.36.25562
14922.93.37.0/2622.93.37.1 to 22.93.37.6222.93.37.6362
15022.93.37.64/2622.93.37.65 to 22.93.37.12622.93.37.12762
15122.93.37.128/2622.93.37.129 to 22.93.37.19022.93.37.19162
15222.93.37.192/2622.93.37.193 to 22.93.37.25422.93.37.25562
15322.93.38.0/2622.93.38.1 to 22.93.38.6222.93.38.6362
15422.93.38.64/2622.93.38.65 to 22.93.38.12622.93.38.12762
15522.93.38.128/2622.93.38.129 to 22.93.38.19022.93.38.19162
15622.93.38.192/2622.93.38.193 to 22.93.38.25422.93.38.25562
15722.93.39.0/2622.93.39.1 to 22.93.39.6222.93.39.6362
15822.93.39.64/2622.93.39.65 to 22.93.39.12622.93.39.12762
15922.93.39.128/2622.93.39.129 to 22.93.39.19022.93.39.19162
16022.93.39.192/2622.93.39.193 to 22.93.39.25422.93.39.25562
16122.93.40.0/2622.93.40.1 to 22.93.40.6222.93.40.6362
16222.93.40.64/2622.93.40.65 to 22.93.40.12622.93.40.12762
16322.93.40.128/2622.93.40.129 to 22.93.40.19022.93.40.19162
16422.93.40.192/2622.93.40.193 to 22.93.40.25422.93.40.25562
16522.93.41.0/2622.93.41.1 to 22.93.41.6222.93.41.6362
16622.93.41.64/2622.93.41.65 to 22.93.41.12622.93.41.12762
16722.93.41.128/2622.93.41.129 to 22.93.41.19022.93.41.19162
16822.93.41.192/2622.93.41.193 to 22.93.41.25422.93.41.25562
16922.93.42.0/2622.93.42.1 to 22.93.42.6222.93.42.6362
17022.93.42.64/2622.93.42.65 to 22.93.42.12622.93.42.12762
17122.93.42.128/2622.93.42.129 to 22.93.42.19022.93.42.19162
17222.93.42.192/2622.93.42.193 to 22.93.42.25422.93.42.25562
17322.93.43.0/2622.93.43.1 to 22.93.43.6222.93.43.6362
17422.93.43.64/2622.93.43.65 to 22.93.43.12622.93.43.12762
17522.93.43.128/2622.93.43.129 to 22.93.43.19022.93.43.19162
17622.93.43.192/2622.93.43.193 to 22.93.43.25422.93.43.25562
17722.93.44.0/2622.93.44.1 to 22.93.44.6222.93.44.6362
17822.93.44.64/2622.93.44.65 to 22.93.44.12622.93.44.12762
17922.93.44.128/2622.93.44.129 to 22.93.44.19022.93.44.19162
18022.93.44.192/2622.93.44.193 to 22.93.44.25422.93.44.25562
18122.93.45.0/2622.93.45.1 to 22.93.45.6222.93.45.6362
18222.93.45.64/2622.93.45.65 to 22.93.45.12622.93.45.12762
18322.93.45.128/2622.93.45.129 to 22.93.45.19022.93.45.19162
18422.93.45.192/2622.93.45.193 to 22.93.45.25422.93.45.25562
18522.93.46.0/2622.93.46.1 to 22.93.46.6222.93.46.6362
18622.93.46.64/2622.93.46.65 to 22.93.46.12622.93.46.12762
18722.93.46.128/2622.93.46.129 to 22.93.46.19022.93.46.19162
18822.93.46.192/2622.93.46.193 to 22.93.46.25422.93.46.25562
18922.93.47.0/2622.93.47.1 to 22.93.47.6222.93.47.6362
19022.93.47.64/2622.93.47.65 to 22.93.47.12622.93.47.12762
19122.93.47.128/2622.93.47.129 to 22.93.47.19022.93.47.19162
19222.93.47.192/2622.93.47.193 to 22.93.47.25422.93.47.25562
19322.93.48.0/2622.93.48.1 to 22.93.48.6222.93.48.6362
19422.93.48.64/2622.93.48.65 to 22.93.48.12622.93.48.12762
19522.93.48.128/2622.93.48.129 to 22.93.48.19022.93.48.19162
19622.93.48.192/2622.93.48.193 to 22.93.48.25422.93.48.25562
19722.93.49.0/2622.93.49.1 to 22.93.49.6222.93.49.6362
19822.93.49.64/2622.93.49.65 to 22.93.49.12622.93.49.12762
19922.93.49.128/2622.93.49.129 to 22.93.49.19022.93.49.19162
20022.93.49.192/2622.93.49.193 to 22.93.49.25422.93.49.25562
20122.93.50.0/2622.93.50.1 to 22.93.50.6222.93.50.6362
20222.93.50.64/2622.93.50.65 to 22.93.50.12622.93.50.12762
20322.93.50.128/2622.93.50.129 to 22.93.50.19022.93.50.19162
20422.93.50.192/2622.93.50.193 to 22.93.50.25422.93.50.25562
20522.93.51.0/2622.93.51.1 to 22.93.51.6222.93.51.6362
20622.93.51.64/2622.93.51.65 to 22.93.51.12622.93.51.12762
20722.93.51.128/2622.93.51.129 to 22.93.51.19022.93.51.19162
20822.93.51.192/2622.93.51.193 to 22.93.51.25422.93.51.25562
20922.93.52.0/2622.93.52.1 to 22.93.52.6222.93.52.6362
21022.93.52.64/2622.93.52.65 to 22.93.52.12622.93.52.12762
21122.93.52.128/2622.93.52.129 to 22.93.52.19022.93.52.19162
21222.93.52.192/2622.93.52.193 to 22.93.52.25422.93.52.25562
21322.93.53.0/2622.93.53.1 to 22.93.53.6222.93.53.6362
21422.93.53.64/2622.93.53.65 to 22.93.53.12622.93.53.12762
21522.93.53.128/2622.93.53.129 to 22.93.53.19022.93.53.19162
21622.93.53.192/2622.93.53.193 to 22.93.53.25422.93.53.25562
21722.93.54.0/2622.93.54.1 to 22.93.54.6222.93.54.6362
21822.93.54.64/2622.93.54.65 to 22.93.54.12622.93.54.12762
21922.93.54.128/2622.93.54.129 to 22.93.54.19022.93.54.19162
22022.93.54.192/2622.93.54.193 to 22.93.54.25422.93.54.25562
22122.93.55.0/2622.93.55.1 to 22.93.55.6222.93.55.6362
22222.93.55.64/2622.93.55.65 to 22.93.55.12622.93.55.12762
22322.93.55.128/2622.93.55.129 to 22.93.55.19022.93.55.19162
22422.93.55.192/2622.93.55.193 to 22.93.55.25422.93.55.25562
22522.93.56.0/2622.93.56.1 to 22.93.56.6222.93.56.6362
22622.93.56.64/2622.93.56.65 to 22.93.56.12622.93.56.12762
22722.93.56.128/2622.93.56.129 to 22.93.56.19022.93.56.19162
22822.93.56.192/2622.93.56.193 to 22.93.56.25422.93.56.25562
22922.93.57.0/2622.93.57.1 to 22.93.57.6222.93.57.6362
23022.93.57.64/2622.93.57.65 to 22.93.57.12622.93.57.12762
23122.93.57.128/2622.93.57.129 to 22.93.57.19022.93.57.19162
23222.93.57.192/2622.93.57.193 to 22.93.57.25422.93.57.25562
23322.93.58.0/2622.93.58.1 to 22.93.58.6222.93.58.6362
23422.93.58.64/2622.93.58.65 to 22.93.58.12622.93.58.12762
23522.93.58.128/2622.93.58.129 to 22.93.58.19022.93.58.19162
23622.93.58.192/2622.93.58.193 to 22.93.58.25422.93.58.25562
23722.93.59.0/2622.93.59.1 to 22.93.59.6222.93.59.6362
23822.93.59.64/2622.93.59.65 to 22.93.59.12622.93.59.12762
23922.93.59.128/2622.93.59.129 to 22.93.59.19022.93.59.19162
24022.93.59.192/2622.93.59.193 to 22.93.59.25422.93.59.25562
24122.93.60.0/2622.93.60.1 to 22.93.60.6222.93.60.6362
24222.93.60.64/2622.93.60.65 to 22.93.60.12622.93.60.12762
24322.93.60.128/2622.93.60.129 to 22.93.60.19022.93.60.19162
24422.93.60.192/2622.93.60.193 to 22.93.60.25422.93.60.25562
24522.93.61.0/2622.93.61.1 to 22.93.61.6222.93.61.6362
24622.93.61.64/2622.93.61.65 to 22.93.61.12622.93.61.12762
24722.93.61.128/2622.93.61.129 to 22.93.61.19022.93.61.19162
24822.93.61.192/2622.93.61.193 to 22.93.61.25422.93.61.25562
24922.93.62.0/2622.93.62.1 to 22.93.62.6222.93.62.6362
25022.93.62.64/2622.93.62.65 to 22.93.62.12622.93.62.12762
25122.93.62.128/2622.93.62.129 to 22.93.62.19022.93.62.19162
25222.93.62.192/2622.93.62.193 to 22.93.62.25422.93.62.25562
25322.93.63.0/2622.93.63.1 to 22.93.63.6222.93.63.6362
25422.93.63.64/2622.93.63.65 to 22.93.63.12622.93.63.12762
25522.93.63.128/2622.93.63.129 to 22.93.63.19022.93.63.19162
25622.93.63.192/2622.93.63.193 to 22.93.63.25422.93.63.25562

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.