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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.

Network92.167.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
92.167.0.0
Broadcast address
92.167.255.255
First usable
92.167.0.1
Last usable
92.167.255.254
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 5CA70000 · Integer 1554448384 to 1554513919
Reverse DNS zone
167.92.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011100.10100111..00000000.0000000092.167.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01011100.10100111..00000000.0000000092.167.0.0
Broadcast01011100.10100111..11111111.1111111192.167.255.255
Split into smaller subnets/28
/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)

92.167.0.0/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
192.167.0.0/2892.167.0.1 to 92.167.0.1492.167.0.1514
292.167.0.16/2892.167.0.17 to 92.167.0.3092.167.0.3114
392.167.0.32/2892.167.0.33 to 92.167.0.4692.167.0.4714
492.167.0.48/2892.167.0.49 to 92.167.0.6292.167.0.6314
592.167.0.64/2892.167.0.65 to 92.167.0.7892.167.0.7914
692.167.0.80/2892.167.0.81 to 92.167.0.9492.167.0.9514
792.167.0.96/2892.167.0.97 to 92.167.0.11092.167.0.11114
892.167.0.112/2892.167.0.113 to 92.167.0.12692.167.0.12714
992.167.0.128/2892.167.0.129 to 92.167.0.14292.167.0.14314
1092.167.0.144/2892.167.0.145 to 92.167.0.15892.167.0.15914
1192.167.0.160/2892.167.0.161 to 92.167.0.17492.167.0.17514
1292.167.0.176/2892.167.0.177 to 92.167.0.19092.167.0.19114
1392.167.0.192/2892.167.0.193 to 92.167.0.20692.167.0.20714
1492.167.0.208/2892.167.0.209 to 92.167.0.22292.167.0.22314
1592.167.0.224/2892.167.0.225 to 92.167.0.23892.167.0.23914
1692.167.0.240/2892.167.0.241 to 92.167.0.25492.167.0.25514
1792.167.1.0/2892.167.1.1 to 92.167.1.1492.167.1.1514
1892.167.1.16/2892.167.1.17 to 92.167.1.3092.167.1.3114
1992.167.1.32/2892.167.1.33 to 92.167.1.4692.167.1.4714
2092.167.1.48/2892.167.1.49 to 92.167.1.6292.167.1.6314
2192.167.1.64/2892.167.1.65 to 92.167.1.7892.167.1.7914
2292.167.1.80/2892.167.1.81 to 92.167.1.9492.167.1.9514
2392.167.1.96/2892.167.1.97 to 92.167.1.11092.167.1.11114
2492.167.1.112/2892.167.1.113 to 92.167.1.12692.167.1.12714
2592.167.1.128/2892.167.1.129 to 92.167.1.14292.167.1.14314
2692.167.1.144/2892.167.1.145 to 92.167.1.15892.167.1.15914
2792.167.1.160/2892.167.1.161 to 92.167.1.17492.167.1.17514
2892.167.1.176/2892.167.1.177 to 92.167.1.19092.167.1.19114
2992.167.1.192/2892.167.1.193 to 92.167.1.20692.167.1.20714
3092.167.1.208/2892.167.1.209 to 92.167.1.22292.167.1.22314
3192.167.1.224/2892.167.1.225 to 92.167.1.23892.167.1.23914
3292.167.1.240/2892.167.1.241 to 92.167.1.25492.167.1.25514
3392.167.2.0/2892.167.2.1 to 92.167.2.1492.167.2.1514
3492.167.2.16/2892.167.2.17 to 92.167.2.3092.167.2.3114
3592.167.2.32/2892.167.2.33 to 92.167.2.4692.167.2.4714
3692.167.2.48/2892.167.2.49 to 92.167.2.6292.167.2.6314
3792.167.2.64/2892.167.2.65 to 92.167.2.7892.167.2.7914
3892.167.2.80/2892.167.2.81 to 92.167.2.9492.167.2.9514
3992.167.2.96/2892.167.2.97 to 92.167.2.11092.167.2.11114
4092.167.2.112/2892.167.2.113 to 92.167.2.12692.167.2.12714
4192.167.2.128/2892.167.2.129 to 92.167.2.14292.167.2.14314
4292.167.2.144/2892.167.2.145 to 92.167.2.15892.167.2.15914
4392.167.2.160/2892.167.2.161 to 92.167.2.17492.167.2.17514
4492.167.2.176/2892.167.2.177 to 92.167.2.19092.167.2.19114
4592.167.2.192/2892.167.2.193 to 92.167.2.20692.167.2.20714
4692.167.2.208/2892.167.2.209 to 92.167.2.22292.167.2.22314
4792.167.2.224/2892.167.2.225 to 92.167.2.23892.167.2.23914
4892.167.2.240/2892.167.2.241 to 92.167.2.25492.167.2.25514
4992.167.3.0/2892.167.3.1 to 92.167.3.1492.167.3.1514
5092.167.3.16/2892.167.3.17 to 92.167.3.3092.167.3.3114
5192.167.3.32/2892.167.3.33 to 92.167.3.4692.167.3.4714
5292.167.3.48/2892.167.3.49 to 92.167.3.6292.167.3.6314
5392.167.3.64/2892.167.3.65 to 92.167.3.7892.167.3.7914
5492.167.3.80/2892.167.3.81 to 92.167.3.9492.167.3.9514
5592.167.3.96/2892.167.3.97 to 92.167.3.11092.167.3.11114
5692.167.3.112/2892.167.3.113 to 92.167.3.12692.167.3.12714
5792.167.3.128/2892.167.3.129 to 92.167.3.14292.167.3.14314
5892.167.3.144/2892.167.3.145 to 92.167.3.15892.167.3.15914
5992.167.3.160/2892.167.3.161 to 92.167.3.17492.167.3.17514
6092.167.3.176/2892.167.3.177 to 92.167.3.19092.167.3.19114
6192.167.3.192/2892.167.3.193 to 92.167.3.20692.167.3.20714
6292.167.3.208/2892.167.3.209 to 92.167.3.22292.167.3.22314
6392.167.3.224/2892.167.3.225 to 92.167.3.23892.167.3.23914
6492.167.3.240/2892.167.3.241 to 92.167.3.25492.167.3.25514
6592.167.4.0/2892.167.4.1 to 92.167.4.1492.167.4.1514
6692.167.4.16/2892.167.4.17 to 92.167.4.3092.167.4.3114
6792.167.4.32/2892.167.4.33 to 92.167.4.4692.167.4.4714
6892.167.4.48/2892.167.4.49 to 92.167.4.6292.167.4.6314
6992.167.4.64/2892.167.4.65 to 92.167.4.7892.167.4.7914
7092.167.4.80/2892.167.4.81 to 92.167.4.9492.167.4.9514
7192.167.4.96/2892.167.4.97 to 92.167.4.11092.167.4.11114
7292.167.4.112/2892.167.4.113 to 92.167.4.12692.167.4.12714
7392.167.4.128/2892.167.4.129 to 92.167.4.14292.167.4.14314
7492.167.4.144/2892.167.4.145 to 92.167.4.15892.167.4.15914
7592.167.4.160/2892.167.4.161 to 92.167.4.17492.167.4.17514
7692.167.4.176/2892.167.4.177 to 92.167.4.19092.167.4.19114
7792.167.4.192/2892.167.4.193 to 92.167.4.20692.167.4.20714
7892.167.4.208/2892.167.4.209 to 92.167.4.22292.167.4.22314
7992.167.4.224/2892.167.4.225 to 92.167.4.23892.167.4.23914
8092.167.4.240/2892.167.4.241 to 92.167.4.25492.167.4.25514
8192.167.5.0/2892.167.5.1 to 92.167.5.1492.167.5.1514
8292.167.5.16/2892.167.5.17 to 92.167.5.3092.167.5.3114
8392.167.5.32/2892.167.5.33 to 92.167.5.4692.167.5.4714
8492.167.5.48/2892.167.5.49 to 92.167.5.6292.167.5.6314
8592.167.5.64/2892.167.5.65 to 92.167.5.7892.167.5.7914
8692.167.5.80/2892.167.5.81 to 92.167.5.9492.167.5.9514
8792.167.5.96/2892.167.5.97 to 92.167.5.11092.167.5.11114
8892.167.5.112/2892.167.5.113 to 92.167.5.12692.167.5.12714
8992.167.5.128/2892.167.5.129 to 92.167.5.14292.167.5.14314
9092.167.5.144/2892.167.5.145 to 92.167.5.15892.167.5.15914
9192.167.5.160/2892.167.5.161 to 92.167.5.17492.167.5.17514
9292.167.5.176/2892.167.5.177 to 92.167.5.19092.167.5.19114
9392.167.5.192/2892.167.5.193 to 92.167.5.20692.167.5.20714
9492.167.5.208/2892.167.5.209 to 92.167.5.22292.167.5.22314
9592.167.5.224/2892.167.5.225 to 92.167.5.23892.167.5.23914
9692.167.5.240/2892.167.5.241 to 92.167.5.25492.167.5.25514
9792.167.6.0/2892.167.6.1 to 92.167.6.1492.167.6.1514
9892.167.6.16/2892.167.6.17 to 92.167.6.3092.167.6.3114
9992.167.6.32/2892.167.6.33 to 92.167.6.4692.167.6.4714
10092.167.6.48/2892.167.6.49 to 92.167.6.6292.167.6.6314
10192.167.6.64/2892.167.6.65 to 92.167.6.7892.167.6.7914
10292.167.6.80/2892.167.6.81 to 92.167.6.9492.167.6.9514
10392.167.6.96/2892.167.6.97 to 92.167.6.11092.167.6.11114
10492.167.6.112/2892.167.6.113 to 92.167.6.12692.167.6.12714
10592.167.6.128/2892.167.6.129 to 92.167.6.14292.167.6.14314
10692.167.6.144/2892.167.6.145 to 92.167.6.15892.167.6.15914
10792.167.6.160/2892.167.6.161 to 92.167.6.17492.167.6.17514
10892.167.6.176/2892.167.6.177 to 92.167.6.19092.167.6.19114
10992.167.6.192/2892.167.6.193 to 92.167.6.20692.167.6.20714
11092.167.6.208/2892.167.6.209 to 92.167.6.22292.167.6.22314
11192.167.6.224/2892.167.6.225 to 92.167.6.23892.167.6.23914
11292.167.6.240/2892.167.6.241 to 92.167.6.25492.167.6.25514
11392.167.7.0/2892.167.7.1 to 92.167.7.1492.167.7.1514
11492.167.7.16/2892.167.7.17 to 92.167.7.3092.167.7.3114
11592.167.7.32/2892.167.7.33 to 92.167.7.4692.167.7.4714
11692.167.7.48/2892.167.7.49 to 92.167.7.6292.167.7.6314
11792.167.7.64/2892.167.7.65 to 92.167.7.7892.167.7.7914
11892.167.7.80/2892.167.7.81 to 92.167.7.9492.167.7.9514
11992.167.7.96/2892.167.7.97 to 92.167.7.11092.167.7.11114
12092.167.7.112/2892.167.7.113 to 92.167.7.12692.167.7.12714
12192.167.7.128/2892.167.7.129 to 92.167.7.14292.167.7.14314
12292.167.7.144/2892.167.7.145 to 92.167.7.15892.167.7.15914
12392.167.7.160/2892.167.7.161 to 92.167.7.17492.167.7.17514
12492.167.7.176/2892.167.7.177 to 92.167.7.19092.167.7.19114
12592.167.7.192/2892.167.7.193 to 92.167.7.20692.167.7.20714
12692.167.7.208/2892.167.7.209 to 92.167.7.22292.167.7.22314
12792.167.7.224/2892.167.7.225 to 92.167.7.23892.167.7.23914
12892.167.7.240/2892.167.7.241 to 92.167.7.25492.167.7.25514
12992.167.8.0/2892.167.8.1 to 92.167.8.1492.167.8.1514
13092.167.8.16/2892.167.8.17 to 92.167.8.3092.167.8.3114
13192.167.8.32/2892.167.8.33 to 92.167.8.4692.167.8.4714
13292.167.8.48/2892.167.8.49 to 92.167.8.6292.167.8.6314
13392.167.8.64/2892.167.8.65 to 92.167.8.7892.167.8.7914
13492.167.8.80/2892.167.8.81 to 92.167.8.9492.167.8.9514
13592.167.8.96/2892.167.8.97 to 92.167.8.11092.167.8.11114
13692.167.8.112/2892.167.8.113 to 92.167.8.12692.167.8.12714
13792.167.8.128/2892.167.8.129 to 92.167.8.14292.167.8.14314
13892.167.8.144/2892.167.8.145 to 92.167.8.15892.167.8.15914
13992.167.8.160/2892.167.8.161 to 92.167.8.17492.167.8.17514
14092.167.8.176/2892.167.8.177 to 92.167.8.19092.167.8.19114
14192.167.8.192/2892.167.8.193 to 92.167.8.20692.167.8.20714
14292.167.8.208/2892.167.8.209 to 92.167.8.22292.167.8.22314
14392.167.8.224/2892.167.8.225 to 92.167.8.23892.167.8.23914
14492.167.8.240/2892.167.8.241 to 92.167.8.25492.167.8.25514
14592.167.9.0/2892.167.9.1 to 92.167.9.1492.167.9.1514
14692.167.9.16/2892.167.9.17 to 92.167.9.3092.167.9.3114
14792.167.9.32/2892.167.9.33 to 92.167.9.4692.167.9.4714
14892.167.9.48/2892.167.9.49 to 92.167.9.6292.167.9.6314
14992.167.9.64/2892.167.9.65 to 92.167.9.7892.167.9.7914
15092.167.9.80/2892.167.9.81 to 92.167.9.9492.167.9.9514
15192.167.9.96/2892.167.9.97 to 92.167.9.11092.167.9.11114
15292.167.9.112/2892.167.9.113 to 92.167.9.12692.167.9.12714
15392.167.9.128/2892.167.9.129 to 92.167.9.14292.167.9.14314
15492.167.9.144/2892.167.9.145 to 92.167.9.15892.167.9.15914
15592.167.9.160/2892.167.9.161 to 92.167.9.17492.167.9.17514
15692.167.9.176/2892.167.9.177 to 92.167.9.19092.167.9.19114
15792.167.9.192/2892.167.9.193 to 92.167.9.20692.167.9.20714
15892.167.9.208/2892.167.9.209 to 92.167.9.22292.167.9.22314
15992.167.9.224/2892.167.9.225 to 92.167.9.23892.167.9.23914
16092.167.9.240/2892.167.9.241 to 92.167.9.25492.167.9.25514
16192.167.10.0/2892.167.10.1 to 92.167.10.1492.167.10.1514
16292.167.10.16/2892.167.10.17 to 92.167.10.3092.167.10.3114
16392.167.10.32/2892.167.10.33 to 92.167.10.4692.167.10.4714
16492.167.10.48/2892.167.10.49 to 92.167.10.6292.167.10.6314
16592.167.10.64/2892.167.10.65 to 92.167.10.7892.167.10.7914
16692.167.10.80/2892.167.10.81 to 92.167.10.9492.167.10.9514
16792.167.10.96/2892.167.10.97 to 92.167.10.11092.167.10.11114
16892.167.10.112/2892.167.10.113 to 92.167.10.12692.167.10.12714
16992.167.10.128/2892.167.10.129 to 92.167.10.14292.167.10.14314
17092.167.10.144/2892.167.10.145 to 92.167.10.15892.167.10.15914
17192.167.10.160/2892.167.10.161 to 92.167.10.17492.167.10.17514
17292.167.10.176/2892.167.10.177 to 92.167.10.19092.167.10.19114
17392.167.10.192/2892.167.10.193 to 92.167.10.20692.167.10.20714
17492.167.10.208/2892.167.10.209 to 92.167.10.22292.167.10.22314
17592.167.10.224/2892.167.10.225 to 92.167.10.23892.167.10.23914
17692.167.10.240/2892.167.10.241 to 92.167.10.25492.167.10.25514
17792.167.11.0/2892.167.11.1 to 92.167.11.1492.167.11.1514
17892.167.11.16/2892.167.11.17 to 92.167.11.3092.167.11.3114
17992.167.11.32/2892.167.11.33 to 92.167.11.4692.167.11.4714
18092.167.11.48/2892.167.11.49 to 92.167.11.6292.167.11.6314
18192.167.11.64/2892.167.11.65 to 92.167.11.7892.167.11.7914
18292.167.11.80/2892.167.11.81 to 92.167.11.9492.167.11.9514
18392.167.11.96/2892.167.11.97 to 92.167.11.11092.167.11.11114
18492.167.11.112/2892.167.11.113 to 92.167.11.12692.167.11.12714
18592.167.11.128/2892.167.11.129 to 92.167.11.14292.167.11.14314
18692.167.11.144/2892.167.11.145 to 92.167.11.15892.167.11.15914
18792.167.11.160/2892.167.11.161 to 92.167.11.17492.167.11.17514
18892.167.11.176/2892.167.11.177 to 92.167.11.19092.167.11.19114
18992.167.11.192/2892.167.11.193 to 92.167.11.20692.167.11.20714
19092.167.11.208/2892.167.11.209 to 92.167.11.22292.167.11.22314
19192.167.11.224/2892.167.11.225 to 92.167.11.23892.167.11.23914
19292.167.11.240/2892.167.11.241 to 92.167.11.25492.167.11.25514
19392.167.12.0/2892.167.12.1 to 92.167.12.1492.167.12.1514
19492.167.12.16/2892.167.12.17 to 92.167.12.3092.167.12.3114
19592.167.12.32/2892.167.12.33 to 92.167.12.4692.167.12.4714
19692.167.12.48/2892.167.12.49 to 92.167.12.6292.167.12.6314
19792.167.12.64/2892.167.12.65 to 92.167.12.7892.167.12.7914
19892.167.12.80/2892.167.12.81 to 92.167.12.9492.167.12.9514
19992.167.12.96/2892.167.12.97 to 92.167.12.11092.167.12.11114
20092.167.12.112/2892.167.12.113 to 92.167.12.12692.167.12.12714
20192.167.12.128/2892.167.12.129 to 92.167.12.14292.167.12.14314
20292.167.12.144/2892.167.12.145 to 92.167.12.15892.167.12.15914
20392.167.12.160/2892.167.12.161 to 92.167.12.17492.167.12.17514
20492.167.12.176/2892.167.12.177 to 92.167.12.19092.167.12.19114
20592.167.12.192/2892.167.12.193 to 92.167.12.20692.167.12.20714
20692.167.12.208/2892.167.12.209 to 92.167.12.22292.167.12.22314
20792.167.12.224/2892.167.12.225 to 92.167.12.23892.167.12.23914
20892.167.12.240/2892.167.12.241 to 92.167.12.25492.167.12.25514
20992.167.13.0/2892.167.13.1 to 92.167.13.1492.167.13.1514
21092.167.13.16/2892.167.13.17 to 92.167.13.3092.167.13.3114
21192.167.13.32/2892.167.13.33 to 92.167.13.4692.167.13.4714
21292.167.13.48/2892.167.13.49 to 92.167.13.6292.167.13.6314
21392.167.13.64/2892.167.13.65 to 92.167.13.7892.167.13.7914
21492.167.13.80/2892.167.13.81 to 92.167.13.9492.167.13.9514
21592.167.13.96/2892.167.13.97 to 92.167.13.11092.167.13.11114
21692.167.13.112/2892.167.13.113 to 92.167.13.12692.167.13.12714
21792.167.13.128/2892.167.13.129 to 92.167.13.14292.167.13.14314
21892.167.13.144/2892.167.13.145 to 92.167.13.15892.167.13.15914
21992.167.13.160/2892.167.13.161 to 92.167.13.17492.167.13.17514
22092.167.13.176/2892.167.13.177 to 92.167.13.19092.167.13.19114
22192.167.13.192/2892.167.13.193 to 92.167.13.20692.167.13.20714
22292.167.13.208/2892.167.13.209 to 92.167.13.22292.167.13.22314
22392.167.13.224/2892.167.13.225 to 92.167.13.23892.167.13.23914
22492.167.13.240/2892.167.13.241 to 92.167.13.25492.167.13.25514
22592.167.14.0/2892.167.14.1 to 92.167.14.1492.167.14.1514
22692.167.14.16/2892.167.14.17 to 92.167.14.3092.167.14.3114
22792.167.14.32/2892.167.14.33 to 92.167.14.4692.167.14.4714
22892.167.14.48/2892.167.14.49 to 92.167.14.6292.167.14.6314
22992.167.14.64/2892.167.14.65 to 92.167.14.7892.167.14.7914
23092.167.14.80/2892.167.14.81 to 92.167.14.9492.167.14.9514
23192.167.14.96/2892.167.14.97 to 92.167.14.11092.167.14.11114
23292.167.14.112/2892.167.14.113 to 92.167.14.12692.167.14.12714
23392.167.14.128/2892.167.14.129 to 92.167.14.14292.167.14.14314
23492.167.14.144/2892.167.14.145 to 92.167.14.15892.167.14.15914
23592.167.14.160/2892.167.14.161 to 92.167.14.17492.167.14.17514
23692.167.14.176/2892.167.14.177 to 92.167.14.19092.167.14.19114
23792.167.14.192/2892.167.14.193 to 92.167.14.20692.167.14.20714
23892.167.14.208/2892.167.14.209 to 92.167.14.22292.167.14.22314
23992.167.14.224/2892.167.14.225 to 92.167.14.23892.167.14.23914
24092.167.14.240/2892.167.14.241 to 92.167.14.25492.167.14.25514
24192.167.15.0/2892.167.15.1 to 92.167.15.1492.167.15.1514
24292.167.15.16/2892.167.15.17 to 92.167.15.3092.167.15.3114
24392.167.15.32/2892.167.15.33 to 92.167.15.4692.167.15.4714
24492.167.15.48/2892.167.15.49 to 92.167.15.6292.167.15.6314
24592.167.15.64/2892.167.15.65 to 92.167.15.7892.167.15.7914
24692.167.15.80/2892.167.15.81 to 92.167.15.9492.167.15.9514
24792.167.15.96/2892.167.15.97 to 92.167.15.11092.167.15.11114
24892.167.15.112/2892.167.15.113 to 92.167.15.12692.167.15.12714
24992.167.15.128/2892.167.15.129 to 92.167.15.14292.167.15.14314
25092.167.15.144/2892.167.15.145 to 92.167.15.15892.167.15.15914
25192.167.15.160/2892.167.15.161 to 92.167.15.17492.167.15.17514
25292.167.15.176/2892.167.15.177 to 92.167.15.19092.167.15.19114
25392.167.15.192/2892.167.15.193 to 92.167.15.20692.167.15.20714
25492.167.15.208/2892.167.15.209 to 92.167.15.22292.167.15.22314
25592.167.15.224/2892.167.15.225 to 92.167.15.23892.167.15.23914
25692.167.15.240/2892.167.15.241 to 92.167.15.25492.167.15.25514

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

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.