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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.

Network22.0.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
22.0.0.0
Broadcast address
22.31.255.255
First usable
22.0.0.1
Last usable
22.31.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Public public
Old class
A (default /8)
As numbers
Hex 16000000 · Integer 369098752 to 371195903
Reverse DNS zones
0.22.in-addr.arpa
1.22.in-addr.arpa
2.22.in-addr.arpa
3.22.in-addr.arpa
4.22.in-addr.arpa
5.22.in-addr.arpa
6.22.in-addr.arpa
7.22.in-addr.arpa
8.22.in-addr.arpa
9.22.in-addr.arpa
10.22.in-addr.arpa
11.22.in-addr.arpa
12.22.in-addr.arpa
13.22.in-addr.arpa
14.22.in-addr.arpa
15.22.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00010110.00000000.00000000.0000000022.0.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network00010110.00000000.00000000.0000000022.0.0.0
Broadcast00010110.00011111.11111111.1111111122.31.255.255
Split into smaller subnets/19
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

22.0.0.0/11 makes 256 subnets of /19.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
122.0.0.0/1922.0.0.1 to 22.0.31.25422.0.31.2558,190
222.0.32.0/1922.0.32.1 to 22.0.63.25422.0.63.2558,190
322.0.64.0/1922.0.64.1 to 22.0.95.25422.0.95.2558,190
422.0.96.0/1922.0.96.1 to 22.0.127.25422.0.127.2558,190
522.0.128.0/1922.0.128.1 to 22.0.159.25422.0.159.2558,190
622.0.160.0/1922.0.160.1 to 22.0.191.25422.0.191.2558,190
722.0.192.0/1922.0.192.1 to 22.0.223.25422.0.223.2558,190
822.0.224.0/1922.0.224.1 to 22.0.255.25422.0.255.2558,190
922.1.0.0/1922.1.0.1 to 22.1.31.25422.1.31.2558,190
1022.1.32.0/1922.1.32.1 to 22.1.63.25422.1.63.2558,190
1122.1.64.0/1922.1.64.1 to 22.1.95.25422.1.95.2558,190
1222.1.96.0/1922.1.96.1 to 22.1.127.25422.1.127.2558,190
1322.1.128.0/1922.1.128.1 to 22.1.159.25422.1.159.2558,190
1422.1.160.0/1922.1.160.1 to 22.1.191.25422.1.191.2558,190
1522.1.192.0/1922.1.192.1 to 22.1.223.25422.1.223.2558,190
1622.1.224.0/1922.1.224.1 to 22.1.255.25422.1.255.2558,190
1722.2.0.0/1922.2.0.1 to 22.2.31.25422.2.31.2558,190
1822.2.32.0/1922.2.32.1 to 22.2.63.25422.2.63.2558,190
1922.2.64.0/1922.2.64.1 to 22.2.95.25422.2.95.2558,190
2022.2.96.0/1922.2.96.1 to 22.2.127.25422.2.127.2558,190
2122.2.128.0/1922.2.128.1 to 22.2.159.25422.2.159.2558,190
2222.2.160.0/1922.2.160.1 to 22.2.191.25422.2.191.2558,190
2322.2.192.0/1922.2.192.1 to 22.2.223.25422.2.223.2558,190
2422.2.224.0/1922.2.224.1 to 22.2.255.25422.2.255.2558,190
2522.3.0.0/1922.3.0.1 to 22.3.31.25422.3.31.2558,190
2622.3.32.0/1922.3.32.1 to 22.3.63.25422.3.63.2558,190
2722.3.64.0/1922.3.64.1 to 22.3.95.25422.3.95.2558,190
2822.3.96.0/1922.3.96.1 to 22.3.127.25422.3.127.2558,190
2922.3.128.0/1922.3.128.1 to 22.3.159.25422.3.159.2558,190
3022.3.160.0/1922.3.160.1 to 22.3.191.25422.3.191.2558,190
3122.3.192.0/1922.3.192.1 to 22.3.223.25422.3.223.2558,190
3222.3.224.0/1922.3.224.1 to 22.3.255.25422.3.255.2558,190
3322.4.0.0/1922.4.0.1 to 22.4.31.25422.4.31.2558,190
3422.4.32.0/1922.4.32.1 to 22.4.63.25422.4.63.2558,190
3522.4.64.0/1922.4.64.1 to 22.4.95.25422.4.95.2558,190
3622.4.96.0/1922.4.96.1 to 22.4.127.25422.4.127.2558,190
3722.4.128.0/1922.4.128.1 to 22.4.159.25422.4.159.2558,190
3822.4.160.0/1922.4.160.1 to 22.4.191.25422.4.191.2558,190
3922.4.192.0/1922.4.192.1 to 22.4.223.25422.4.223.2558,190
4022.4.224.0/1922.4.224.1 to 22.4.255.25422.4.255.2558,190
4122.5.0.0/1922.5.0.1 to 22.5.31.25422.5.31.2558,190
4222.5.32.0/1922.5.32.1 to 22.5.63.25422.5.63.2558,190
4322.5.64.0/1922.5.64.1 to 22.5.95.25422.5.95.2558,190
4422.5.96.0/1922.5.96.1 to 22.5.127.25422.5.127.2558,190
4522.5.128.0/1922.5.128.1 to 22.5.159.25422.5.159.2558,190
4622.5.160.0/1922.5.160.1 to 22.5.191.25422.5.191.2558,190
4722.5.192.0/1922.5.192.1 to 22.5.223.25422.5.223.2558,190
4822.5.224.0/1922.5.224.1 to 22.5.255.25422.5.255.2558,190
4922.6.0.0/1922.6.0.1 to 22.6.31.25422.6.31.2558,190
5022.6.32.0/1922.6.32.1 to 22.6.63.25422.6.63.2558,190
5122.6.64.0/1922.6.64.1 to 22.6.95.25422.6.95.2558,190
5222.6.96.0/1922.6.96.1 to 22.6.127.25422.6.127.2558,190
5322.6.128.0/1922.6.128.1 to 22.6.159.25422.6.159.2558,190
5422.6.160.0/1922.6.160.1 to 22.6.191.25422.6.191.2558,190
5522.6.192.0/1922.6.192.1 to 22.6.223.25422.6.223.2558,190
5622.6.224.0/1922.6.224.1 to 22.6.255.25422.6.255.2558,190
5722.7.0.0/1922.7.0.1 to 22.7.31.25422.7.31.2558,190
5822.7.32.0/1922.7.32.1 to 22.7.63.25422.7.63.2558,190
5922.7.64.0/1922.7.64.1 to 22.7.95.25422.7.95.2558,190
6022.7.96.0/1922.7.96.1 to 22.7.127.25422.7.127.2558,190
6122.7.128.0/1922.7.128.1 to 22.7.159.25422.7.159.2558,190
6222.7.160.0/1922.7.160.1 to 22.7.191.25422.7.191.2558,190
6322.7.192.0/1922.7.192.1 to 22.7.223.25422.7.223.2558,190
6422.7.224.0/1922.7.224.1 to 22.7.255.25422.7.255.2558,190
6522.8.0.0/1922.8.0.1 to 22.8.31.25422.8.31.2558,190
6622.8.32.0/1922.8.32.1 to 22.8.63.25422.8.63.2558,190
6722.8.64.0/1922.8.64.1 to 22.8.95.25422.8.95.2558,190
6822.8.96.0/1922.8.96.1 to 22.8.127.25422.8.127.2558,190
6922.8.128.0/1922.8.128.1 to 22.8.159.25422.8.159.2558,190
7022.8.160.0/1922.8.160.1 to 22.8.191.25422.8.191.2558,190
7122.8.192.0/1922.8.192.1 to 22.8.223.25422.8.223.2558,190
7222.8.224.0/1922.8.224.1 to 22.8.255.25422.8.255.2558,190
7322.9.0.0/1922.9.0.1 to 22.9.31.25422.9.31.2558,190
7422.9.32.0/1922.9.32.1 to 22.9.63.25422.9.63.2558,190
7522.9.64.0/1922.9.64.1 to 22.9.95.25422.9.95.2558,190
7622.9.96.0/1922.9.96.1 to 22.9.127.25422.9.127.2558,190
7722.9.128.0/1922.9.128.1 to 22.9.159.25422.9.159.2558,190
7822.9.160.0/1922.9.160.1 to 22.9.191.25422.9.191.2558,190
7922.9.192.0/1922.9.192.1 to 22.9.223.25422.9.223.2558,190
8022.9.224.0/1922.9.224.1 to 22.9.255.25422.9.255.2558,190
8122.10.0.0/1922.10.0.1 to 22.10.31.25422.10.31.2558,190
8222.10.32.0/1922.10.32.1 to 22.10.63.25422.10.63.2558,190
8322.10.64.0/1922.10.64.1 to 22.10.95.25422.10.95.2558,190
8422.10.96.0/1922.10.96.1 to 22.10.127.25422.10.127.2558,190
8522.10.128.0/1922.10.128.1 to 22.10.159.25422.10.159.2558,190
8622.10.160.0/1922.10.160.1 to 22.10.191.25422.10.191.2558,190
8722.10.192.0/1922.10.192.1 to 22.10.223.25422.10.223.2558,190
8822.10.224.0/1922.10.224.1 to 22.10.255.25422.10.255.2558,190
8922.11.0.0/1922.11.0.1 to 22.11.31.25422.11.31.2558,190
9022.11.32.0/1922.11.32.1 to 22.11.63.25422.11.63.2558,190
9122.11.64.0/1922.11.64.1 to 22.11.95.25422.11.95.2558,190
9222.11.96.0/1922.11.96.1 to 22.11.127.25422.11.127.2558,190
9322.11.128.0/1922.11.128.1 to 22.11.159.25422.11.159.2558,190
9422.11.160.0/1922.11.160.1 to 22.11.191.25422.11.191.2558,190
9522.11.192.0/1922.11.192.1 to 22.11.223.25422.11.223.2558,190
9622.11.224.0/1922.11.224.1 to 22.11.255.25422.11.255.2558,190
9722.12.0.0/1922.12.0.1 to 22.12.31.25422.12.31.2558,190
9822.12.32.0/1922.12.32.1 to 22.12.63.25422.12.63.2558,190
9922.12.64.0/1922.12.64.1 to 22.12.95.25422.12.95.2558,190
10022.12.96.0/1922.12.96.1 to 22.12.127.25422.12.127.2558,190
10122.12.128.0/1922.12.128.1 to 22.12.159.25422.12.159.2558,190
10222.12.160.0/1922.12.160.1 to 22.12.191.25422.12.191.2558,190
10322.12.192.0/1922.12.192.1 to 22.12.223.25422.12.223.2558,190
10422.12.224.0/1922.12.224.1 to 22.12.255.25422.12.255.2558,190
10522.13.0.0/1922.13.0.1 to 22.13.31.25422.13.31.2558,190
10622.13.32.0/1922.13.32.1 to 22.13.63.25422.13.63.2558,190
10722.13.64.0/1922.13.64.1 to 22.13.95.25422.13.95.2558,190
10822.13.96.0/1922.13.96.1 to 22.13.127.25422.13.127.2558,190
10922.13.128.0/1922.13.128.1 to 22.13.159.25422.13.159.2558,190
11022.13.160.0/1922.13.160.1 to 22.13.191.25422.13.191.2558,190
11122.13.192.0/1922.13.192.1 to 22.13.223.25422.13.223.2558,190
11222.13.224.0/1922.13.224.1 to 22.13.255.25422.13.255.2558,190
11322.14.0.0/1922.14.0.1 to 22.14.31.25422.14.31.2558,190
11422.14.32.0/1922.14.32.1 to 22.14.63.25422.14.63.2558,190
11522.14.64.0/1922.14.64.1 to 22.14.95.25422.14.95.2558,190
11622.14.96.0/1922.14.96.1 to 22.14.127.25422.14.127.2558,190
11722.14.128.0/1922.14.128.1 to 22.14.159.25422.14.159.2558,190
11822.14.160.0/1922.14.160.1 to 22.14.191.25422.14.191.2558,190
11922.14.192.0/1922.14.192.1 to 22.14.223.25422.14.223.2558,190
12022.14.224.0/1922.14.224.1 to 22.14.255.25422.14.255.2558,190
12122.15.0.0/1922.15.0.1 to 22.15.31.25422.15.31.2558,190
12222.15.32.0/1922.15.32.1 to 22.15.63.25422.15.63.2558,190
12322.15.64.0/1922.15.64.1 to 22.15.95.25422.15.95.2558,190
12422.15.96.0/1922.15.96.1 to 22.15.127.25422.15.127.2558,190
12522.15.128.0/1922.15.128.1 to 22.15.159.25422.15.159.2558,190
12622.15.160.0/1922.15.160.1 to 22.15.191.25422.15.191.2558,190
12722.15.192.0/1922.15.192.1 to 22.15.223.25422.15.223.2558,190
12822.15.224.0/1922.15.224.1 to 22.15.255.25422.15.255.2558,190
12922.16.0.0/1922.16.0.1 to 22.16.31.25422.16.31.2558,190
13022.16.32.0/1922.16.32.1 to 22.16.63.25422.16.63.2558,190
13122.16.64.0/1922.16.64.1 to 22.16.95.25422.16.95.2558,190
13222.16.96.0/1922.16.96.1 to 22.16.127.25422.16.127.2558,190
13322.16.128.0/1922.16.128.1 to 22.16.159.25422.16.159.2558,190
13422.16.160.0/1922.16.160.1 to 22.16.191.25422.16.191.2558,190
13522.16.192.0/1922.16.192.1 to 22.16.223.25422.16.223.2558,190
13622.16.224.0/1922.16.224.1 to 22.16.255.25422.16.255.2558,190
13722.17.0.0/1922.17.0.1 to 22.17.31.25422.17.31.2558,190
13822.17.32.0/1922.17.32.1 to 22.17.63.25422.17.63.2558,190
13922.17.64.0/1922.17.64.1 to 22.17.95.25422.17.95.2558,190
14022.17.96.0/1922.17.96.1 to 22.17.127.25422.17.127.2558,190
14122.17.128.0/1922.17.128.1 to 22.17.159.25422.17.159.2558,190
14222.17.160.0/1922.17.160.1 to 22.17.191.25422.17.191.2558,190
14322.17.192.0/1922.17.192.1 to 22.17.223.25422.17.223.2558,190
14422.17.224.0/1922.17.224.1 to 22.17.255.25422.17.255.2558,190
14522.18.0.0/1922.18.0.1 to 22.18.31.25422.18.31.2558,190
14622.18.32.0/1922.18.32.1 to 22.18.63.25422.18.63.2558,190
14722.18.64.0/1922.18.64.1 to 22.18.95.25422.18.95.2558,190
14822.18.96.0/1922.18.96.1 to 22.18.127.25422.18.127.2558,190
14922.18.128.0/1922.18.128.1 to 22.18.159.25422.18.159.2558,190
15022.18.160.0/1922.18.160.1 to 22.18.191.25422.18.191.2558,190
15122.18.192.0/1922.18.192.1 to 22.18.223.25422.18.223.2558,190
15222.18.224.0/1922.18.224.1 to 22.18.255.25422.18.255.2558,190
15322.19.0.0/1922.19.0.1 to 22.19.31.25422.19.31.2558,190
15422.19.32.0/1922.19.32.1 to 22.19.63.25422.19.63.2558,190
15522.19.64.0/1922.19.64.1 to 22.19.95.25422.19.95.2558,190
15622.19.96.0/1922.19.96.1 to 22.19.127.25422.19.127.2558,190
15722.19.128.0/1922.19.128.1 to 22.19.159.25422.19.159.2558,190
15822.19.160.0/1922.19.160.1 to 22.19.191.25422.19.191.2558,190
15922.19.192.0/1922.19.192.1 to 22.19.223.25422.19.223.2558,190
16022.19.224.0/1922.19.224.1 to 22.19.255.25422.19.255.2558,190
16122.20.0.0/1922.20.0.1 to 22.20.31.25422.20.31.2558,190
16222.20.32.0/1922.20.32.1 to 22.20.63.25422.20.63.2558,190
16322.20.64.0/1922.20.64.1 to 22.20.95.25422.20.95.2558,190
16422.20.96.0/1922.20.96.1 to 22.20.127.25422.20.127.2558,190
16522.20.128.0/1922.20.128.1 to 22.20.159.25422.20.159.2558,190
16622.20.160.0/1922.20.160.1 to 22.20.191.25422.20.191.2558,190
16722.20.192.0/1922.20.192.1 to 22.20.223.25422.20.223.2558,190
16822.20.224.0/1922.20.224.1 to 22.20.255.25422.20.255.2558,190
16922.21.0.0/1922.21.0.1 to 22.21.31.25422.21.31.2558,190
17022.21.32.0/1922.21.32.1 to 22.21.63.25422.21.63.2558,190
17122.21.64.0/1922.21.64.1 to 22.21.95.25422.21.95.2558,190
17222.21.96.0/1922.21.96.1 to 22.21.127.25422.21.127.2558,190
17322.21.128.0/1922.21.128.1 to 22.21.159.25422.21.159.2558,190
17422.21.160.0/1922.21.160.1 to 22.21.191.25422.21.191.2558,190
17522.21.192.0/1922.21.192.1 to 22.21.223.25422.21.223.2558,190
17622.21.224.0/1922.21.224.1 to 22.21.255.25422.21.255.2558,190
17722.22.0.0/1922.22.0.1 to 22.22.31.25422.22.31.2558,190
17822.22.32.0/1922.22.32.1 to 22.22.63.25422.22.63.2558,190
17922.22.64.0/1922.22.64.1 to 22.22.95.25422.22.95.2558,190
18022.22.96.0/1922.22.96.1 to 22.22.127.25422.22.127.2558,190
18122.22.128.0/1922.22.128.1 to 22.22.159.25422.22.159.2558,190
18222.22.160.0/1922.22.160.1 to 22.22.191.25422.22.191.2558,190
18322.22.192.0/1922.22.192.1 to 22.22.223.25422.22.223.2558,190
18422.22.224.0/1922.22.224.1 to 22.22.255.25422.22.255.2558,190
18522.23.0.0/1922.23.0.1 to 22.23.31.25422.23.31.2558,190
18622.23.32.0/1922.23.32.1 to 22.23.63.25422.23.63.2558,190
18722.23.64.0/1922.23.64.1 to 22.23.95.25422.23.95.2558,190
18822.23.96.0/1922.23.96.1 to 22.23.127.25422.23.127.2558,190
18922.23.128.0/1922.23.128.1 to 22.23.159.25422.23.159.2558,190
19022.23.160.0/1922.23.160.1 to 22.23.191.25422.23.191.2558,190
19122.23.192.0/1922.23.192.1 to 22.23.223.25422.23.223.2558,190
19222.23.224.0/1922.23.224.1 to 22.23.255.25422.23.255.2558,190
19322.24.0.0/1922.24.0.1 to 22.24.31.25422.24.31.2558,190
19422.24.32.0/1922.24.32.1 to 22.24.63.25422.24.63.2558,190
19522.24.64.0/1922.24.64.1 to 22.24.95.25422.24.95.2558,190
19622.24.96.0/1922.24.96.1 to 22.24.127.25422.24.127.2558,190
19722.24.128.0/1922.24.128.1 to 22.24.159.25422.24.159.2558,190
19822.24.160.0/1922.24.160.1 to 22.24.191.25422.24.191.2558,190
19922.24.192.0/1922.24.192.1 to 22.24.223.25422.24.223.2558,190
20022.24.224.0/1922.24.224.1 to 22.24.255.25422.24.255.2558,190
20122.25.0.0/1922.25.0.1 to 22.25.31.25422.25.31.2558,190
20222.25.32.0/1922.25.32.1 to 22.25.63.25422.25.63.2558,190
20322.25.64.0/1922.25.64.1 to 22.25.95.25422.25.95.2558,190
20422.25.96.0/1922.25.96.1 to 22.25.127.25422.25.127.2558,190
20522.25.128.0/1922.25.128.1 to 22.25.159.25422.25.159.2558,190
20622.25.160.0/1922.25.160.1 to 22.25.191.25422.25.191.2558,190
20722.25.192.0/1922.25.192.1 to 22.25.223.25422.25.223.2558,190
20822.25.224.0/1922.25.224.1 to 22.25.255.25422.25.255.2558,190
20922.26.0.0/1922.26.0.1 to 22.26.31.25422.26.31.2558,190
21022.26.32.0/1922.26.32.1 to 22.26.63.25422.26.63.2558,190
21122.26.64.0/1922.26.64.1 to 22.26.95.25422.26.95.2558,190
21222.26.96.0/1922.26.96.1 to 22.26.127.25422.26.127.2558,190
21322.26.128.0/1922.26.128.1 to 22.26.159.25422.26.159.2558,190
21422.26.160.0/1922.26.160.1 to 22.26.191.25422.26.191.2558,190
21522.26.192.0/1922.26.192.1 to 22.26.223.25422.26.223.2558,190
21622.26.224.0/1922.26.224.1 to 22.26.255.25422.26.255.2558,190
21722.27.0.0/1922.27.0.1 to 22.27.31.25422.27.31.2558,190
21822.27.32.0/1922.27.32.1 to 22.27.63.25422.27.63.2558,190
21922.27.64.0/1922.27.64.1 to 22.27.95.25422.27.95.2558,190
22022.27.96.0/1922.27.96.1 to 22.27.127.25422.27.127.2558,190
22122.27.128.0/1922.27.128.1 to 22.27.159.25422.27.159.2558,190
22222.27.160.0/1922.27.160.1 to 22.27.191.25422.27.191.2558,190
22322.27.192.0/1922.27.192.1 to 22.27.223.25422.27.223.2558,190
22422.27.224.0/1922.27.224.1 to 22.27.255.25422.27.255.2558,190
22522.28.0.0/1922.28.0.1 to 22.28.31.25422.28.31.2558,190
22622.28.32.0/1922.28.32.1 to 22.28.63.25422.28.63.2558,190
22722.28.64.0/1922.28.64.1 to 22.28.95.25422.28.95.2558,190
22822.28.96.0/1922.28.96.1 to 22.28.127.25422.28.127.2558,190
22922.28.128.0/1922.28.128.1 to 22.28.159.25422.28.159.2558,190
23022.28.160.0/1922.28.160.1 to 22.28.191.25422.28.191.2558,190
23122.28.192.0/1922.28.192.1 to 22.28.223.25422.28.223.2558,190
23222.28.224.0/1922.28.224.1 to 22.28.255.25422.28.255.2558,190
23322.29.0.0/1922.29.0.1 to 22.29.31.25422.29.31.2558,190
23422.29.32.0/1922.29.32.1 to 22.29.63.25422.29.63.2558,190
23522.29.64.0/1922.29.64.1 to 22.29.95.25422.29.95.2558,190
23622.29.96.0/1922.29.96.1 to 22.29.127.25422.29.127.2558,190
23722.29.128.0/1922.29.128.1 to 22.29.159.25422.29.159.2558,190
23822.29.160.0/1922.29.160.1 to 22.29.191.25422.29.191.2558,190
23922.29.192.0/1922.29.192.1 to 22.29.223.25422.29.223.2558,190
24022.29.224.0/1922.29.224.1 to 22.29.255.25422.29.255.2558,190
24122.30.0.0/1922.30.0.1 to 22.30.31.25422.30.31.2558,190
24222.30.32.0/1922.30.32.1 to 22.30.63.25422.30.63.2558,190
24322.30.64.0/1922.30.64.1 to 22.30.95.25422.30.95.2558,190
24422.30.96.0/1922.30.96.1 to 22.30.127.25422.30.127.2558,190
24522.30.128.0/1922.30.128.1 to 22.30.159.25422.30.159.2558,190
24622.30.160.0/1922.30.160.1 to 22.30.191.25422.30.191.2558,190
24722.30.192.0/1922.30.192.1 to 22.30.223.25422.30.223.2558,190
24822.30.224.0/1922.30.224.1 to 22.30.255.25422.30.255.2558,190
24922.31.0.0/1922.31.0.1 to 22.31.31.25422.31.31.2558,190
25022.31.32.0/1922.31.32.1 to 22.31.63.25422.31.63.2558,190
25122.31.64.0/1922.31.64.1 to 22.31.95.25422.31.95.2558,190
25222.31.96.0/1922.31.96.1 to 22.31.127.25422.31.127.2558,190
25322.31.128.0/1922.31.128.1 to 22.31.159.25422.31.159.2558,190
25422.31.160.0/1922.31.160.1 to 22.31.191.25422.31.191.2558,190
25522.31.192.0/1922.31.192.1 to 22.31.223.25422.31.223.2558,190
25622.31.224.0/1922.31.224.1 to 22.31.255.25422.31.255.2558,190

IPv4 CIDR reference (/0 to /32)

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

IPv6 prefix reference

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

Private and special ranges

IPv4

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

IPv6

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

About this tool

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

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

Common questions

Why are two addresses lost in every IPv4 subnet?

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

What size of IPv6 network should a LAN use?

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

What is a wildcard mask?

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

Which ranges can I use inside an office?

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