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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.

Network22.2.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
22.2.0.0
Broadcast address
22.2.127.255
First usable
22.2.0.1
Last usable
22.2.127.254
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 16020000 · Integer 369229824 to 369262591
Reverse DNS zones
0.2.22.in-addr.arpa
1.2.22.in-addr.arpa
2.2.22.in-addr.arpa
3.2.22.in-addr.arpa
4.2.22.in-addr.arpa
5.2.22.in-addr.arpa
6.2.22.in-addr.arpa
7.2.22.in-addr.arpa
8.2.22.in-addr.arpa
9.2.22.in-addr.arpa
10.2.22.in-addr.arpa
11.2.22.in-addr.arpa
12.2.22.in-addr.arpa
13.2.22.in-addr.arpa
14.2.22.in-addr.arpa
15.2.22.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
Address00010110.00000010.00000000.0000000022.2.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network00010110.00000010.00000000.0000000022.2.0.0
Broadcast00010110.00000010.01111111.1111111122.2.127.255
Split into smaller subnets/28

22.2.0.0/17 makes 2,048 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
122.2.0.0/2822.2.0.1 to 22.2.0.1422.2.0.1514
222.2.0.16/2822.2.0.17 to 22.2.0.3022.2.0.3114
322.2.0.32/2822.2.0.33 to 22.2.0.4622.2.0.4714
422.2.0.48/2822.2.0.49 to 22.2.0.6222.2.0.6314
522.2.0.64/2822.2.0.65 to 22.2.0.7822.2.0.7914
622.2.0.80/2822.2.0.81 to 22.2.0.9422.2.0.9514
722.2.0.96/2822.2.0.97 to 22.2.0.11022.2.0.11114
822.2.0.112/2822.2.0.113 to 22.2.0.12622.2.0.12714
922.2.0.128/2822.2.0.129 to 22.2.0.14222.2.0.14314
1022.2.0.144/2822.2.0.145 to 22.2.0.15822.2.0.15914
1122.2.0.160/2822.2.0.161 to 22.2.0.17422.2.0.17514
1222.2.0.176/2822.2.0.177 to 22.2.0.19022.2.0.19114
1322.2.0.192/2822.2.0.193 to 22.2.0.20622.2.0.20714
1422.2.0.208/2822.2.0.209 to 22.2.0.22222.2.0.22314
1522.2.0.224/2822.2.0.225 to 22.2.0.23822.2.0.23914
1622.2.0.240/2822.2.0.241 to 22.2.0.25422.2.0.25514
1722.2.1.0/2822.2.1.1 to 22.2.1.1422.2.1.1514
1822.2.1.16/2822.2.1.17 to 22.2.1.3022.2.1.3114
1922.2.1.32/2822.2.1.33 to 22.2.1.4622.2.1.4714
2022.2.1.48/2822.2.1.49 to 22.2.1.6222.2.1.6314
2122.2.1.64/2822.2.1.65 to 22.2.1.7822.2.1.7914
2222.2.1.80/2822.2.1.81 to 22.2.1.9422.2.1.9514
2322.2.1.96/2822.2.1.97 to 22.2.1.11022.2.1.11114
2422.2.1.112/2822.2.1.113 to 22.2.1.12622.2.1.12714
2522.2.1.128/2822.2.1.129 to 22.2.1.14222.2.1.14314
2622.2.1.144/2822.2.1.145 to 22.2.1.15822.2.1.15914
2722.2.1.160/2822.2.1.161 to 22.2.1.17422.2.1.17514
2822.2.1.176/2822.2.1.177 to 22.2.1.19022.2.1.19114
2922.2.1.192/2822.2.1.193 to 22.2.1.20622.2.1.20714
3022.2.1.208/2822.2.1.209 to 22.2.1.22222.2.1.22314
3122.2.1.224/2822.2.1.225 to 22.2.1.23822.2.1.23914
3222.2.1.240/2822.2.1.241 to 22.2.1.25422.2.1.25514
3322.2.2.0/2822.2.2.1 to 22.2.2.1422.2.2.1514
3422.2.2.16/2822.2.2.17 to 22.2.2.3022.2.2.3114
3522.2.2.32/2822.2.2.33 to 22.2.2.4622.2.2.4714
3622.2.2.48/2822.2.2.49 to 22.2.2.6222.2.2.6314
3722.2.2.64/2822.2.2.65 to 22.2.2.7822.2.2.7914
3822.2.2.80/2822.2.2.81 to 22.2.2.9422.2.2.9514
3922.2.2.96/2822.2.2.97 to 22.2.2.11022.2.2.11114
4022.2.2.112/2822.2.2.113 to 22.2.2.12622.2.2.12714
4122.2.2.128/2822.2.2.129 to 22.2.2.14222.2.2.14314
4222.2.2.144/2822.2.2.145 to 22.2.2.15822.2.2.15914
4322.2.2.160/2822.2.2.161 to 22.2.2.17422.2.2.17514
4422.2.2.176/2822.2.2.177 to 22.2.2.19022.2.2.19114
4522.2.2.192/2822.2.2.193 to 22.2.2.20622.2.2.20714
4622.2.2.208/2822.2.2.209 to 22.2.2.22222.2.2.22314
4722.2.2.224/2822.2.2.225 to 22.2.2.23822.2.2.23914
4822.2.2.240/2822.2.2.241 to 22.2.2.25422.2.2.25514
4922.2.3.0/2822.2.3.1 to 22.2.3.1422.2.3.1514
5022.2.3.16/2822.2.3.17 to 22.2.3.3022.2.3.3114
5122.2.3.32/2822.2.3.33 to 22.2.3.4622.2.3.4714
5222.2.3.48/2822.2.3.49 to 22.2.3.6222.2.3.6314
5322.2.3.64/2822.2.3.65 to 22.2.3.7822.2.3.7914
5422.2.3.80/2822.2.3.81 to 22.2.3.9422.2.3.9514
5522.2.3.96/2822.2.3.97 to 22.2.3.11022.2.3.11114
5622.2.3.112/2822.2.3.113 to 22.2.3.12622.2.3.12714
5722.2.3.128/2822.2.3.129 to 22.2.3.14222.2.3.14314
5822.2.3.144/2822.2.3.145 to 22.2.3.15822.2.3.15914
5922.2.3.160/2822.2.3.161 to 22.2.3.17422.2.3.17514
6022.2.3.176/2822.2.3.177 to 22.2.3.19022.2.3.19114
6122.2.3.192/2822.2.3.193 to 22.2.3.20622.2.3.20714
6222.2.3.208/2822.2.3.209 to 22.2.3.22222.2.3.22314
6322.2.3.224/2822.2.3.225 to 22.2.3.23822.2.3.23914
6422.2.3.240/2822.2.3.241 to 22.2.3.25422.2.3.25514
6522.2.4.0/2822.2.4.1 to 22.2.4.1422.2.4.1514
6622.2.4.16/2822.2.4.17 to 22.2.4.3022.2.4.3114
6722.2.4.32/2822.2.4.33 to 22.2.4.4622.2.4.4714
6822.2.4.48/2822.2.4.49 to 22.2.4.6222.2.4.6314
6922.2.4.64/2822.2.4.65 to 22.2.4.7822.2.4.7914
7022.2.4.80/2822.2.4.81 to 22.2.4.9422.2.4.9514
7122.2.4.96/2822.2.4.97 to 22.2.4.11022.2.4.11114
7222.2.4.112/2822.2.4.113 to 22.2.4.12622.2.4.12714
7322.2.4.128/2822.2.4.129 to 22.2.4.14222.2.4.14314
7422.2.4.144/2822.2.4.145 to 22.2.4.15822.2.4.15914
7522.2.4.160/2822.2.4.161 to 22.2.4.17422.2.4.17514
7622.2.4.176/2822.2.4.177 to 22.2.4.19022.2.4.19114
7722.2.4.192/2822.2.4.193 to 22.2.4.20622.2.4.20714
7822.2.4.208/2822.2.4.209 to 22.2.4.22222.2.4.22314
7922.2.4.224/2822.2.4.225 to 22.2.4.23822.2.4.23914
8022.2.4.240/2822.2.4.241 to 22.2.4.25422.2.4.25514
8122.2.5.0/2822.2.5.1 to 22.2.5.1422.2.5.1514
8222.2.5.16/2822.2.5.17 to 22.2.5.3022.2.5.3114
8322.2.5.32/2822.2.5.33 to 22.2.5.4622.2.5.4714
8422.2.5.48/2822.2.5.49 to 22.2.5.6222.2.5.6314
8522.2.5.64/2822.2.5.65 to 22.2.5.7822.2.5.7914
8622.2.5.80/2822.2.5.81 to 22.2.5.9422.2.5.9514
8722.2.5.96/2822.2.5.97 to 22.2.5.11022.2.5.11114
8822.2.5.112/2822.2.5.113 to 22.2.5.12622.2.5.12714
8922.2.5.128/2822.2.5.129 to 22.2.5.14222.2.5.14314
9022.2.5.144/2822.2.5.145 to 22.2.5.15822.2.5.15914
9122.2.5.160/2822.2.5.161 to 22.2.5.17422.2.5.17514
9222.2.5.176/2822.2.5.177 to 22.2.5.19022.2.5.19114
9322.2.5.192/2822.2.5.193 to 22.2.5.20622.2.5.20714
9422.2.5.208/2822.2.5.209 to 22.2.5.22222.2.5.22314
9522.2.5.224/2822.2.5.225 to 22.2.5.23822.2.5.23914
9622.2.5.240/2822.2.5.241 to 22.2.5.25422.2.5.25514
9722.2.6.0/2822.2.6.1 to 22.2.6.1422.2.6.1514
9822.2.6.16/2822.2.6.17 to 22.2.6.3022.2.6.3114
9922.2.6.32/2822.2.6.33 to 22.2.6.4622.2.6.4714
10022.2.6.48/2822.2.6.49 to 22.2.6.6222.2.6.6314
10122.2.6.64/2822.2.6.65 to 22.2.6.7822.2.6.7914
10222.2.6.80/2822.2.6.81 to 22.2.6.9422.2.6.9514
10322.2.6.96/2822.2.6.97 to 22.2.6.11022.2.6.11114
10422.2.6.112/2822.2.6.113 to 22.2.6.12622.2.6.12714
10522.2.6.128/2822.2.6.129 to 22.2.6.14222.2.6.14314
10622.2.6.144/2822.2.6.145 to 22.2.6.15822.2.6.15914
10722.2.6.160/2822.2.6.161 to 22.2.6.17422.2.6.17514
10822.2.6.176/2822.2.6.177 to 22.2.6.19022.2.6.19114
10922.2.6.192/2822.2.6.193 to 22.2.6.20622.2.6.20714
11022.2.6.208/2822.2.6.209 to 22.2.6.22222.2.6.22314
11122.2.6.224/2822.2.6.225 to 22.2.6.23822.2.6.23914
11222.2.6.240/2822.2.6.241 to 22.2.6.25422.2.6.25514
11322.2.7.0/2822.2.7.1 to 22.2.7.1422.2.7.1514
11422.2.7.16/2822.2.7.17 to 22.2.7.3022.2.7.3114
11522.2.7.32/2822.2.7.33 to 22.2.7.4622.2.7.4714
11622.2.7.48/2822.2.7.49 to 22.2.7.6222.2.7.6314
11722.2.7.64/2822.2.7.65 to 22.2.7.7822.2.7.7914
11822.2.7.80/2822.2.7.81 to 22.2.7.9422.2.7.9514
11922.2.7.96/2822.2.7.97 to 22.2.7.11022.2.7.11114
12022.2.7.112/2822.2.7.113 to 22.2.7.12622.2.7.12714
12122.2.7.128/2822.2.7.129 to 22.2.7.14222.2.7.14314
12222.2.7.144/2822.2.7.145 to 22.2.7.15822.2.7.15914
12322.2.7.160/2822.2.7.161 to 22.2.7.17422.2.7.17514
12422.2.7.176/2822.2.7.177 to 22.2.7.19022.2.7.19114
12522.2.7.192/2822.2.7.193 to 22.2.7.20622.2.7.20714
12622.2.7.208/2822.2.7.209 to 22.2.7.22222.2.7.22314
12722.2.7.224/2822.2.7.225 to 22.2.7.23822.2.7.23914
12822.2.7.240/2822.2.7.241 to 22.2.7.25422.2.7.25514
12922.2.8.0/2822.2.8.1 to 22.2.8.1422.2.8.1514
13022.2.8.16/2822.2.8.17 to 22.2.8.3022.2.8.3114
13122.2.8.32/2822.2.8.33 to 22.2.8.4622.2.8.4714
13222.2.8.48/2822.2.8.49 to 22.2.8.6222.2.8.6314
13322.2.8.64/2822.2.8.65 to 22.2.8.7822.2.8.7914
13422.2.8.80/2822.2.8.81 to 22.2.8.9422.2.8.9514
13522.2.8.96/2822.2.8.97 to 22.2.8.11022.2.8.11114
13622.2.8.112/2822.2.8.113 to 22.2.8.12622.2.8.12714
13722.2.8.128/2822.2.8.129 to 22.2.8.14222.2.8.14314
13822.2.8.144/2822.2.8.145 to 22.2.8.15822.2.8.15914
13922.2.8.160/2822.2.8.161 to 22.2.8.17422.2.8.17514
14022.2.8.176/2822.2.8.177 to 22.2.8.19022.2.8.19114
14122.2.8.192/2822.2.8.193 to 22.2.8.20622.2.8.20714
14222.2.8.208/2822.2.8.209 to 22.2.8.22222.2.8.22314
14322.2.8.224/2822.2.8.225 to 22.2.8.23822.2.8.23914
14422.2.8.240/2822.2.8.241 to 22.2.8.25422.2.8.25514
14522.2.9.0/2822.2.9.1 to 22.2.9.1422.2.9.1514
14622.2.9.16/2822.2.9.17 to 22.2.9.3022.2.9.3114
14722.2.9.32/2822.2.9.33 to 22.2.9.4622.2.9.4714
14822.2.9.48/2822.2.9.49 to 22.2.9.6222.2.9.6314
14922.2.9.64/2822.2.9.65 to 22.2.9.7822.2.9.7914
15022.2.9.80/2822.2.9.81 to 22.2.9.9422.2.9.9514
15122.2.9.96/2822.2.9.97 to 22.2.9.11022.2.9.11114
15222.2.9.112/2822.2.9.113 to 22.2.9.12622.2.9.12714
15322.2.9.128/2822.2.9.129 to 22.2.9.14222.2.9.14314
15422.2.9.144/2822.2.9.145 to 22.2.9.15822.2.9.15914
15522.2.9.160/2822.2.9.161 to 22.2.9.17422.2.9.17514
15622.2.9.176/2822.2.9.177 to 22.2.9.19022.2.9.19114
15722.2.9.192/2822.2.9.193 to 22.2.9.20622.2.9.20714
15822.2.9.208/2822.2.9.209 to 22.2.9.22222.2.9.22314
15922.2.9.224/2822.2.9.225 to 22.2.9.23822.2.9.23914
16022.2.9.240/2822.2.9.241 to 22.2.9.25422.2.9.25514
16122.2.10.0/2822.2.10.1 to 22.2.10.1422.2.10.1514
16222.2.10.16/2822.2.10.17 to 22.2.10.3022.2.10.3114
16322.2.10.32/2822.2.10.33 to 22.2.10.4622.2.10.4714
16422.2.10.48/2822.2.10.49 to 22.2.10.6222.2.10.6314
16522.2.10.64/2822.2.10.65 to 22.2.10.7822.2.10.7914
16622.2.10.80/2822.2.10.81 to 22.2.10.9422.2.10.9514
16722.2.10.96/2822.2.10.97 to 22.2.10.11022.2.10.11114
16822.2.10.112/2822.2.10.113 to 22.2.10.12622.2.10.12714
16922.2.10.128/2822.2.10.129 to 22.2.10.14222.2.10.14314
17022.2.10.144/2822.2.10.145 to 22.2.10.15822.2.10.15914
17122.2.10.160/2822.2.10.161 to 22.2.10.17422.2.10.17514
17222.2.10.176/2822.2.10.177 to 22.2.10.19022.2.10.19114
17322.2.10.192/2822.2.10.193 to 22.2.10.20622.2.10.20714
17422.2.10.208/2822.2.10.209 to 22.2.10.22222.2.10.22314
17522.2.10.224/2822.2.10.225 to 22.2.10.23822.2.10.23914
17622.2.10.240/2822.2.10.241 to 22.2.10.25422.2.10.25514
17722.2.11.0/2822.2.11.1 to 22.2.11.1422.2.11.1514
17822.2.11.16/2822.2.11.17 to 22.2.11.3022.2.11.3114
17922.2.11.32/2822.2.11.33 to 22.2.11.4622.2.11.4714
18022.2.11.48/2822.2.11.49 to 22.2.11.6222.2.11.6314
18122.2.11.64/2822.2.11.65 to 22.2.11.7822.2.11.7914
18222.2.11.80/2822.2.11.81 to 22.2.11.9422.2.11.9514
18322.2.11.96/2822.2.11.97 to 22.2.11.11022.2.11.11114
18422.2.11.112/2822.2.11.113 to 22.2.11.12622.2.11.12714
18522.2.11.128/2822.2.11.129 to 22.2.11.14222.2.11.14314
18622.2.11.144/2822.2.11.145 to 22.2.11.15822.2.11.15914
18722.2.11.160/2822.2.11.161 to 22.2.11.17422.2.11.17514
18822.2.11.176/2822.2.11.177 to 22.2.11.19022.2.11.19114
18922.2.11.192/2822.2.11.193 to 22.2.11.20622.2.11.20714
19022.2.11.208/2822.2.11.209 to 22.2.11.22222.2.11.22314
19122.2.11.224/2822.2.11.225 to 22.2.11.23822.2.11.23914
19222.2.11.240/2822.2.11.241 to 22.2.11.25422.2.11.25514
19322.2.12.0/2822.2.12.1 to 22.2.12.1422.2.12.1514
19422.2.12.16/2822.2.12.17 to 22.2.12.3022.2.12.3114
19522.2.12.32/2822.2.12.33 to 22.2.12.4622.2.12.4714
19622.2.12.48/2822.2.12.49 to 22.2.12.6222.2.12.6314
19722.2.12.64/2822.2.12.65 to 22.2.12.7822.2.12.7914
19822.2.12.80/2822.2.12.81 to 22.2.12.9422.2.12.9514
19922.2.12.96/2822.2.12.97 to 22.2.12.11022.2.12.11114
20022.2.12.112/2822.2.12.113 to 22.2.12.12622.2.12.12714
20122.2.12.128/2822.2.12.129 to 22.2.12.14222.2.12.14314
20222.2.12.144/2822.2.12.145 to 22.2.12.15822.2.12.15914
20322.2.12.160/2822.2.12.161 to 22.2.12.17422.2.12.17514
20422.2.12.176/2822.2.12.177 to 22.2.12.19022.2.12.19114
20522.2.12.192/2822.2.12.193 to 22.2.12.20622.2.12.20714
20622.2.12.208/2822.2.12.209 to 22.2.12.22222.2.12.22314
20722.2.12.224/2822.2.12.225 to 22.2.12.23822.2.12.23914
20822.2.12.240/2822.2.12.241 to 22.2.12.25422.2.12.25514
20922.2.13.0/2822.2.13.1 to 22.2.13.1422.2.13.1514
21022.2.13.16/2822.2.13.17 to 22.2.13.3022.2.13.3114
21122.2.13.32/2822.2.13.33 to 22.2.13.4622.2.13.4714
21222.2.13.48/2822.2.13.49 to 22.2.13.6222.2.13.6314
21322.2.13.64/2822.2.13.65 to 22.2.13.7822.2.13.7914
21422.2.13.80/2822.2.13.81 to 22.2.13.9422.2.13.9514
21522.2.13.96/2822.2.13.97 to 22.2.13.11022.2.13.11114
21622.2.13.112/2822.2.13.113 to 22.2.13.12622.2.13.12714
21722.2.13.128/2822.2.13.129 to 22.2.13.14222.2.13.14314
21822.2.13.144/2822.2.13.145 to 22.2.13.15822.2.13.15914
21922.2.13.160/2822.2.13.161 to 22.2.13.17422.2.13.17514
22022.2.13.176/2822.2.13.177 to 22.2.13.19022.2.13.19114
22122.2.13.192/2822.2.13.193 to 22.2.13.20622.2.13.20714
22222.2.13.208/2822.2.13.209 to 22.2.13.22222.2.13.22314
22322.2.13.224/2822.2.13.225 to 22.2.13.23822.2.13.23914
22422.2.13.240/2822.2.13.241 to 22.2.13.25422.2.13.25514
22522.2.14.0/2822.2.14.1 to 22.2.14.1422.2.14.1514
22622.2.14.16/2822.2.14.17 to 22.2.14.3022.2.14.3114
22722.2.14.32/2822.2.14.33 to 22.2.14.4622.2.14.4714
22822.2.14.48/2822.2.14.49 to 22.2.14.6222.2.14.6314
22922.2.14.64/2822.2.14.65 to 22.2.14.7822.2.14.7914
23022.2.14.80/2822.2.14.81 to 22.2.14.9422.2.14.9514
23122.2.14.96/2822.2.14.97 to 22.2.14.11022.2.14.11114
23222.2.14.112/2822.2.14.113 to 22.2.14.12622.2.14.12714
23322.2.14.128/2822.2.14.129 to 22.2.14.14222.2.14.14314
23422.2.14.144/2822.2.14.145 to 22.2.14.15822.2.14.15914
23522.2.14.160/2822.2.14.161 to 22.2.14.17422.2.14.17514
23622.2.14.176/2822.2.14.177 to 22.2.14.19022.2.14.19114
23722.2.14.192/2822.2.14.193 to 22.2.14.20622.2.14.20714
23822.2.14.208/2822.2.14.209 to 22.2.14.22222.2.14.22314
23922.2.14.224/2822.2.14.225 to 22.2.14.23822.2.14.23914
24022.2.14.240/2822.2.14.241 to 22.2.14.25422.2.14.25514
24122.2.15.0/2822.2.15.1 to 22.2.15.1422.2.15.1514
24222.2.15.16/2822.2.15.17 to 22.2.15.3022.2.15.3114
24322.2.15.32/2822.2.15.33 to 22.2.15.4622.2.15.4714
24422.2.15.48/2822.2.15.49 to 22.2.15.6222.2.15.6314
24522.2.15.64/2822.2.15.65 to 22.2.15.7822.2.15.7914
24622.2.15.80/2822.2.15.81 to 22.2.15.9422.2.15.9514
24722.2.15.96/2822.2.15.97 to 22.2.15.11022.2.15.11114
24822.2.15.112/2822.2.15.113 to 22.2.15.12622.2.15.12714
24922.2.15.128/2822.2.15.129 to 22.2.15.14222.2.15.14314
25022.2.15.144/2822.2.15.145 to 22.2.15.15822.2.15.15914
25122.2.15.160/2822.2.15.161 to 22.2.15.17422.2.15.17514
25222.2.15.176/2822.2.15.177 to 22.2.15.19022.2.15.19114
25322.2.15.192/2822.2.15.193 to 22.2.15.20622.2.15.20714
25422.2.15.208/2822.2.15.209 to 22.2.15.22222.2.15.22314
25522.2.15.224/2822.2.15.225 to 22.2.15.23822.2.15.23914
25622.2.15.240/2822.2.15.241 to 22.2.15.25422.2.15.25514

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