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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.

Network55.89.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
55.89.0.0
Broadcast address
55.89.255.255
First usable
55.89.0.1
Last usable
55.89.255.254
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 37590000 · Integer 928579584 to 928645119
Reverse DNS zone
89.55.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110111.01011001..00000000.0000000055.89.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00110111.01011001..00000000.0000000055.89.0.0
Broadcast00110111.01011001..11111111.1111111155.89.255.255
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)

55.89.0.0/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
155.89.0.0/2855.89.0.1 to 55.89.0.1455.89.0.1514
255.89.0.16/2855.89.0.17 to 55.89.0.3055.89.0.3114
355.89.0.32/2855.89.0.33 to 55.89.0.4655.89.0.4714
455.89.0.48/2855.89.0.49 to 55.89.0.6255.89.0.6314
555.89.0.64/2855.89.0.65 to 55.89.0.7855.89.0.7914
655.89.0.80/2855.89.0.81 to 55.89.0.9455.89.0.9514
755.89.0.96/2855.89.0.97 to 55.89.0.11055.89.0.11114
855.89.0.112/2855.89.0.113 to 55.89.0.12655.89.0.12714
955.89.0.128/2855.89.0.129 to 55.89.0.14255.89.0.14314
1055.89.0.144/2855.89.0.145 to 55.89.0.15855.89.0.15914
1155.89.0.160/2855.89.0.161 to 55.89.0.17455.89.0.17514
1255.89.0.176/2855.89.0.177 to 55.89.0.19055.89.0.19114
1355.89.0.192/2855.89.0.193 to 55.89.0.20655.89.0.20714
1455.89.0.208/2855.89.0.209 to 55.89.0.22255.89.0.22314
1555.89.0.224/2855.89.0.225 to 55.89.0.23855.89.0.23914
1655.89.0.240/2855.89.0.241 to 55.89.0.25455.89.0.25514
1755.89.1.0/2855.89.1.1 to 55.89.1.1455.89.1.1514
1855.89.1.16/2855.89.1.17 to 55.89.1.3055.89.1.3114
1955.89.1.32/2855.89.1.33 to 55.89.1.4655.89.1.4714
2055.89.1.48/2855.89.1.49 to 55.89.1.6255.89.1.6314
2155.89.1.64/2855.89.1.65 to 55.89.1.7855.89.1.7914
2255.89.1.80/2855.89.1.81 to 55.89.1.9455.89.1.9514
2355.89.1.96/2855.89.1.97 to 55.89.1.11055.89.1.11114
2455.89.1.112/2855.89.1.113 to 55.89.1.12655.89.1.12714
2555.89.1.128/2855.89.1.129 to 55.89.1.14255.89.1.14314
2655.89.1.144/2855.89.1.145 to 55.89.1.15855.89.1.15914
2755.89.1.160/2855.89.1.161 to 55.89.1.17455.89.1.17514
2855.89.1.176/2855.89.1.177 to 55.89.1.19055.89.1.19114
2955.89.1.192/2855.89.1.193 to 55.89.1.20655.89.1.20714
3055.89.1.208/2855.89.1.209 to 55.89.1.22255.89.1.22314
3155.89.1.224/2855.89.1.225 to 55.89.1.23855.89.1.23914
3255.89.1.240/2855.89.1.241 to 55.89.1.25455.89.1.25514
3355.89.2.0/2855.89.2.1 to 55.89.2.1455.89.2.1514
3455.89.2.16/2855.89.2.17 to 55.89.2.3055.89.2.3114
3555.89.2.32/2855.89.2.33 to 55.89.2.4655.89.2.4714
3655.89.2.48/2855.89.2.49 to 55.89.2.6255.89.2.6314
3755.89.2.64/2855.89.2.65 to 55.89.2.7855.89.2.7914
3855.89.2.80/2855.89.2.81 to 55.89.2.9455.89.2.9514
3955.89.2.96/2855.89.2.97 to 55.89.2.11055.89.2.11114
4055.89.2.112/2855.89.2.113 to 55.89.2.12655.89.2.12714
4155.89.2.128/2855.89.2.129 to 55.89.2.14255.89.2.14314
4255.89.2.144/2855.89.2.145 to 55.89.2.15855.89.2.15914
4355.89.2.160/2855.89.2.161 to 55.89.2.17455.89.2.17514
4455.89.2.176/2855.89.2.177 to 55.89.2.19055.89.2.19114
4555.89.2.192/2855.89.2.193 to 55.89.2.20655.89.2.20714
4655.89.2.208/2855.89.2.209 to 55.89.2.22255.89.2.22314
4755.89.2.224/2855.89.2.225 to 55.89.2.23855.89.2.23914
4855.89.2.240/2855.89.2.241 to 55.89.2.25455.89.2.25514
4955.89.3.0/2855.89.3.1 to 55.89.3.1455.89.3.1514
5055.89.3.16/2855.89.3.17 to 55.89.3.3055.89.3.3114
5155.89.3.32/2855.89.3.33 to 55.89.3.4655.89.3.4714
5255.89.3.48/2855.89.3.49 to 55.89.3.6255.89.3.6314
5355.89.3.64/2855.89.3.65 to 55.89.3.7855.89.3.7914
5455.89.3.80/2855.89.3.81 to 55.89.3.9455.89.3.9514
5555.89.3.96/2855.89.3.97 to 55.89.3.11055.89.3.11114
5655.89.3.112/2855.89.3.113 to 55.89.3.12655.89.3.12714
5755.89.3.128/2855.89.3.129 to 55.89.3.14255.89.3.14314
5855.89.3.144/2855.89.3.145 to 55.89.3.15855.89.3.15914
5955.89.3.160/2855.89.3.161 to 55.89.3.17455.89.3.17514
6055.89.3.176/2855.89.3.177 to 55.89.3.19055.89.3.19114
6155.89.3.192/2855.89.3.193 to 55.89.3.20655.89.3.20714
6255.89.3.208/2855.89.3.209 to 55.89.3.22255.89.3.22314
6355.89.3.224/2855.89.3.225 to 55.89.3.23855.89.3.23914
6455.89.3.240/2855.89.3.241 to 55.89.3.25455.89.3.25514
6555.89.4.0/2855.89.4.1 to 55.89.4.1455.89.4.1514
6655.89.4.16/2855.89.4.17 to 55.89.4.3055.89.4.3114
6755.89.4.32/2855.89.4.33 to 55.89.4.4655.89.4.4714
6855.89.4.48/2855.89.4.49 to 55.89.4.6255.89.4.6314
6955.89.4.64/2855.89.4.65 to 55.89.4.7855.89.4.7914
7055.89.4.80/2855.89.4.81 to 55.89.4.9455.89.4.9514
7155.89.4.96/2855.89.4.97 to 55.89.4.11055.89.4.11114
7255.89.4.112/2855.89.4.113 to 55.89.4.12655.89.4.12714
7355.89.4.128/2855.89.4.129 to 55.89.4.14255.89.4.14314
7455.89.4.144/2855.89.4.145 to 55.89.4.15855.89.4.15914
7555.89.4.160/2855.89.4.161 to 55.89.4.17455.89.4.17514
7655.89.4.176/2855.89.4.177 to 55.89.4.19055.89.4.19114
7755.89.4.192/2855.89.4.193 to 55.89.4.20655.89.4.20714
7855.89.4.208/2855.89.4.209 to 55.89.4.22255.89.4.22314
7955.89.4.224/2855.89.4.225 to 55.89.4.23855.89.4.23914
8055.89.4.240/2855.89.4.241 to 55.89.4.25455.89.4.25514
8155.89.5.0/2855.89.5.1 to 55.89.5.1455.89.5.1514
8255.89.5.16/2855.89.5.17 to 55.89.5.3055.89.5.3114
8355.89.5.32/2855.89.5.33 to 55.89.5.4655.89.5.4714
8455.89.5.48/2855.89.5.49 to 55.89.5.6255.89.5.6314
8555.89.5.64/2855.89.5.65 to 55.89.5.7855.89.5.7914
8655.89.5.80/2855.89.5.81 to 55.89.5.9455.89.5.9514
8755.89.5.96/2855.89.5.97 to 55.89.5.11055.89.5.11114
8855.89.5.112/2855.89.5.113 to 55.89.5.12655.89.5.12714
8955.89.5.128/2855.89.5.129 to 55.89.5.14255.89.5.14314
9055.89.5.144/2855.89.5.145 to 55.89.5.15855.89.5.15914
9155.89.5.160/2855.89.5.161 to 55.89.5.17455.89.5.17514
9255.89.5.176/2855.89.5.177 to 55.89.5.19055.89.5.19114
9355.89.5.192/2855.89.5.193 to 55.89.5.20655.89.5.20714
9455.89.5.208/2855.89.5.209 to 55.89.5.22255.89.5.22314
9555.89.5.224/2855.89.5.225 to 55.89.5.23855.89.5.23914
9655.89.5.240/2855.89.5.241 to 55.89.5.25455.89.5.25514
9755.89.6.0/2855.89.6.1 to 55.89.6.1455.89.6.1514
9855.89.6.16/2855.89.6.17 to 55.89.6.3055.89.6.3114
9955.89.6.32/2855.89.6.33 to 55.89.6.4655.89.6.4714
10055.89.6.48/2855.89.6.49 to 55.89.6.6255.89.6.6314
10155.89.6.64/2855.89.6.65 to 55.89.6.7855.89.6.7914
10255.89.6.80/2855.89.6.81 to 55.89.6.9455.89.6.9514
10355.89.6.96/2855.89.6.97 to 55.89.6.11055.89.6.11114
10455.89.6.112/2855.89.6.113 to 55.89.6.12655.89.6.12714
10555.89.6.128/2855.89.6.129 to 55.89.6.14255.89.6.14314
10655.89.6.144/2855.89.6.145 to 55.89.6.15855.89.6.15914
10755.89.6.160/2855.89.6.161 to 55.89.6.17455.89.6.17514
10855.89.6.176/2855.89.6.177 to 55.89.6.19055.89.6.19114
10955.89.6.192/2855.89.6.193 to 55.89.6.20655.89.6.20714
11055.89.6.208/2855.89.6.209 to 55.89.6.22255.89.6.22314
11155.89.6.224/2855.89.6.225 to 55.89.6.23855.89.6.23914
11255.89.6.240/2855.89.6.241 to 55.89.6.25455.89.6.25514
11355.89.7.0/2855.89.7.1 to 55.89.7.1455.89.7.1514
11455.89.7.16/2855.89.7.17 to 55.89.7.3055.89.7.3114
11555.89.7.32/2855.89.7.33 to 55.89.7.4655.89.7.4714
11655.89.7.48/2855.89.7.49 to 55.89.7.6255.89.7.6314
11755.89.7.64/2855.89.7.65 to 55.89.7.7855.89.7.7914
11855.89.7.80/2855.89.7.81 to 55.89.7.9455.89.7.9514
11955.89.7.96/2855.89.7.97 to 55.89.7.11055.89.7.11114
12055.89.7.112/2855.89.7.113 to 55.89.7.12655.89.7.12714
12155.89.7.128/2855.89.7.129 to 55.89.7.14255.89.7.14314
12255.89.7.144/2855.89.7.145 to 55.89.7.15855.89.7.15914
12355.89.7.160/2855.89.7.161 to 55.89.7.17455.89.7.17514
12455.89.7.176/2855.89.7.177 to 55.89.7.19055.89.7.19114
12555.89.7.192/2855.89.7.193 to 55.89.7.20655.89.7.20714
12655.89.7.208/2855.89.7.209 to 55.89.7.22255.89.7.22314
12755.89.7.224/2855.89.7.225 to 55.89.7.23855.89.7.23914
12855.89.7.240/2855.89.7.241 to 55.89.7.25455.89.7.25514
12955.89.8.0/2855.89.8.1 to 55.89.8.1455.89.8.1514
13055.89.8.16/2855.89.8.17 to 55.89.8.3055.89.8.3114
13155.89.8.32/2855.89.8.33 to 55.89.8.4655.89.8.4714
13255.89.8.48/2855.89.8.49 to 55.89.8.6255.89.8.6314
13355.89.8.64/2855.89.8.65 to 55.89.8.7855.89.8.7914
13455.89.8.80/2855.89.8.81 to 55.89.8.9455.89.8.9514
13555.89.8.96/2855.89.8.97 to 55.89.8.11055.89.8.11114
13655.89.8.112/2855.89.8.113 to 55.89.8.12655.89.8.12714
13755.89.8.128/2855.89.8.129 to 55.89.8.14255.89.8.14314
13855.89.8.144/2855.89.8.145 to 55.89.8.15855.89.8.15914
13955.89.8.160/2855.89.8.161 to 55.89.8.17455.89.8.17514
14055.89.8.176/2855.89.8.177 to 55.89.8.19055.89.8.19114
14155.89.8.192/2855.89.8.193 to 55.89.8.20655.89.8.20714
14255.89.8.208/2855.89.8.209 to 55.89.8.22255.89.8.22314
14355.89.8.224/2855.89.8.225 to 55.89.8.23855.89.8.23914
14455.89.8.240/2855.89.8.241 to 55.89.8.25455.89.8.25514
14555.89.9.0/2855.89.9.1 to 55.89.9.1455.89.9.1514
14655.89.9.16/2855.89.9.17 to 55.89.9.3055.89.9.3114
14755.89.9.32/2855.89.9.33 to 55.89.9.4655.89.9.4714
14855.89.9.48/2855.89.9.49 to 55.89.9.6255.89.9.6314
14955.89.9.64/2855.89.9.65 to 55.89.9.7855.89.9.7914
15055.89.9.80/2855.89.9.81 to 55.89.9.9455.89.9.9514
15155.89.9.96/2855.89.9.97 to 55.89.9.11055.89.9.11114
15255.89.9.112/2855.89.9.113 to 55.89.9.12655.89.9.12714
15355.89.9.128/2855.89.9.129 to 55.89.9.14255.89.9.14314
15455.89.9.144/2855.89.9.145 to 55.89.9.15855.89.9.15914
15555.89.9.160/2855.89.9.161 to 55.89.9.17455.89.9.17514
15655.89.9.176/2855.89.9.177 to 55.89.9.19055.89.9.19114
15755.89.9.192/2855.89.9.193 to 55.89.9.20655.89.9.20714
15855.89.9.208/2855.89.9.209 to 55.89.9.22255.89.9.22314
15955.89.9.224/2855.89.9.225 to 55.89.9.23855.89.9.23914
16055.89.9.240/2855.89.9.241 to 55.89.9.25455.89.9.25514
16155.89.10.0/2855.89.10.1 to 55.89.10.1455.89.10.1514
16255.89.10.16/2855.89.10.17 to 55.89.10.3055.89.10.3114
16355.89.10.32/2855.89.10.33 to 55.89.10.4655.89.10.4714
16455.89.10.48/2855.89.10.49 to 55.89.10.6255.89.10.6314
16555.89.10.64/2855.89.10.65 to 55.89.10.7855.89.10.7914
16655.89.10.80/2855.89.10.81 to 55.89.10.9455.89.10.9514
16755.89.10.96/2855.89.10.97 to 55.89.10.11055.89.10.11114
16855.89.10.112/2855.89.10.113 to 55.89.10.12655.89.10.12714
16955.89.10.128/2855.89.10.129 to 55.89.10.14255.89.10.14314
17055.89.10.144/2855.89.10.145 to 55.89.10.15855.89.10.15914
17155.89.10.160/2855.89.10.161 to 55.89.10.17455.89.10.17514
17255.89.10.176/2855.89.10.177 to 55.89.10.19055.89.10.19114
17355.89.10.192/2855.89.10.193 to 55.89.10.20655.89.10.20714
17455.89.10.208/2855.89.10.209 to 55.89.10.22255.89.10.22314
17555.89.10.224/2855.89.10.225 to 55.89.10.23855.89.10.23914
17655.89.10.240/2855.89.10.241 to 55.89.10.25455.89.10.25514
17755.89.11.0/2855.89.11.1 to 55.89.11.1455.89.11.1514
17855.89.11.16/2855.89.11.17 to 55.89.11.3055.89.11.3114
17955.89.11.32/2855.89.11.33 to 55.89.11.4655.89.11.4714
18055.89.11.48/2855.89.11.49 to 55.89.11.6255.89.11.6314
18155.89.11.64/2855.89.11.65 to 55.89.11.7855.89.11.7914
18255.89.11.80/2855.89.11.81 to 55.89.11.9455.89.11.9514
18355.89.11.96/2855.89.11.97 to 55.89.11.11055.89.11.11114
18455.89.11.112/2855.89.11.113 to 55.89.11.12655.89.11.12714
18555.89.11.128/2855.89.11.129 to 55.89.11.14255.89.11.14314
18655.89.11.144/2855.89.11.145 to 55.89.11.15855.89.11.15914
18755.89.11.160/2855.89.11.161 to 55.89.11.17455.89.11.17514
18855.89.11.176/2855.89.11.177 to 55.89.11.19055.89.11.19114
18955.89.11.192/2855.89.11.193 to 55.89.11.20655.89.11.20714
19055.89.11.208/2855.89.11.209 to 55.89.11.22255.89.11.22314
19155.89.11.224/2855.89.11.225 to 55.89.11.23855.89.11.23914
19255.89.11.240/2855.89.11.241 to 55.89.11.25455.89.11.25514
19355.89.12.0/2855.89.12.1 to 55.89.12.1455.89.12.1514
19455.89.12.16/2855.89.12.17 to 55.89.12.3055.89.12.3114
19555.89.12.32/2855.89.12.33 to 55.89.12.4655.89.12.4714
19655.89.12.48/2855.89.12.49 to 55.89.12.6255.89.12.6314
19755.89.12.64/2855.89.12.65 to 55.89.12.7855.89.12.7914
19855.89.12.80/2855.89.12.81 to 55.89.12.9455.89.12.9514
19955.89.12.96/2855.89.12.97 to 55.89.12.11055.89.12.11114
20055.89.12.112/2855.89.12.113 to 55.89.12.12655.89.12.12714
20155.89.12.128/2855.89.12.129 to 55.89.12.14255.89.12.14314
20255.89.12.144/2855.89.12.145 to 55.89.12.15855.89.12.15914
20355.89.12.160/2855.89.12.161 to 55.89.12.17455.89.12.17514
20455.89.12.176/2855.89.12.177 to 55.89.12.19055.89.12.19114
20555.89.12.192/2855.89.12.193 to 55.89.12.20655.89.12.20714
20655.89.12.208/2855.89.12.209 to 55.89.12.22255.89.12.22314
20755.89.12.224/2855.89.12.225 to 55.89.12.23855.89.12.23914
20855.89.12.240/2855.89.12.241 to 55.89.12.25455.89.12.25514
20955.89.13.0/2855.89.13.1 to 55.89.13.1455.89.13.1514
21055.89.13.16/2855.89.13.17 to 55.89.13.3055.89.13.3114
21155.89.13.32/2855.89.13.33 to 55.89.13.4655.89.13.4714
21255.89.13.48/2855.89.13.49 to 55.89.13.6255.89.13.6314
21355.89.13.64/2855.89.13.65 to 55.89.13.7855.89.13.7914
21455.89.13.80/2855.89.13.81 to 55.89.13.9455.89.13.9514
21555.89.13.96/2855.89.13.97 to 55.89.13.11055.89.13.11114
21655.89.13.112/2855.89.13.113 to 55.89.13.12655.89.13.12714
21755.89.13.128/2855.89.13.129 to 55.89.13.14255.89.13.14314
21855.89.13.144/2855.89.13.145 to 55.89.13.15855.89.13.15914
21955.89.13.160/2855.89.13.161 to 55.89.13.17455.89.13.17514
22055.89.13.176/2855.89.13.177 to 55.89.13.19055.89.13.19114
22155.89.13.192/2855.89.13.193 to 55.89.13.20655.89.13.20714
22255.89.13.208/2855.89.13.209 to 55.89.13.22255.89.13.22314
22355.89.13.224/2855.89.13.225 to 55.89.13.23855.89.13.23914
22455.89.13.240/2855.89.13.241 to 55.89.13.25455.89.13.25514
22555.89.14.0/2855.89.14.1 to 55.89.14.1455.89.14.1514
22655.89.14.16/2855.89.14.17 to 55.89.14.3055.89.14.3114
22755.89.14.32/2855.89.14.33 to 55.89.14.4655.89.14.4714
22855.89.14.48/2855.89.14.49 to 55.89.14.6255.89.14.6314
22955.89.14.64/2855.89.14.65 to 55.89.14.7855.89.14.7914
23055.89.14.80/2855.89.14.81 to 55.89.14.9455.89.14.9514
23155.89.14.96/2855.89.14.97 to 55.89.14.11055.89.14.11114
23255.89.14.112/2855.89.14.113 to 55.89.14.12655.89.14.12714
23355.89.14.128/2855.89.14.129 to 55.89.14.14255.89.14.14314
23455.89.14.144/2855.89.14.145 to 55.89.14.15855.89.14.15914
23555.89.14.160/2855.89.14.161 to 55.89.14.17455.89.14.17514
23655.89.14.176/2855.89.14.177 to 55.89.14.19055.89.14.19114
23755.89.14.192/2855.89.14.193 to 55.89.14.20655.89.14.20714
23855.89.14.208/2855.89.14.209 to 55.89.14.22255.89.14.22314
23955.89.14.224/2855.89.14.225 to 55.89.14.23855.89.14.23914
24055.89.14.240/2855.89.14.241 to 55.89.14.25455.89.14.25514
24155.89.15.0/2855.89.15.1 to 55.89.15.1455.89.15.1514
24255.89.15.16/2855.89.15.17 to 55.89.15.3055.89.15.3114
24355.89.15.32/2855.89.15.33 to 55.89.15.4655.89.15.4714
24455.89.15.48/2855.89.15.49 to 55.89.15.6255.89.15.6314
24555.89.15.64/2855.89.15.65 to 55.89.15.7855.89.15.7914
24655.89.15.80/2855.89.15.81 to 55.89.15.9455.89.15.9514
24755.89.15.96/2855.89.15.97 to 55.89.15.11055.89.15.11114
24855.89.15.112/2855.89.15.113 to 55.89.15.12655.89.15.12714
24955.89.15.128/2855.89.15.129 to 55.89.15.14255.89.15.14314
25055.89.15.144/2855.89.15.145 to 55.89.15.15855.89.15.15914
25155.89.15.160/2855.89.15.161 to 55.89.15.17455.89.15.17514
25255.89.15.176/2855.89.15.177 to 55.89.15.19055.89.15.19114
25355.89.15.192/2855.89.15.193 to 55.89.15.20655.89.15.20714
25455.89.15.208/2855.89.15.209 to 55.89.15.22255.89.15.22314
25555.89.15.224/2855.89.15.225 to 55.89.15.23855.89.15.23914
25655.89.15.240/2855.89.15.241 to 55.89.15.25455.89.15.25514

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.