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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.

Network93.13.0.0/18
Usable hosts16,382
Subnet mask255.255.192.0
Addresses16,384
Network address
93.13.0.0
Broadcast address
93.13.63.255
First usable
93.13.0.1
Last usable
93.13.63.254
Usable hosts
16,382 (16,384 less the network and broadcast addresses)
Subnet mask
255.255.192.0
Wildcard mask
0.0.63.255 (Cisco ACLs, OSPF)
Prefix length
/18
Type
Public public
Old class
A (default /8)
As numbers
Hex 5D0D0000 · Integer 1561133056 to 1561149439
Reverse DNS zones
0.13.93.in-addr.arpa
1.13.93.in-addr.arpa
2.13.93.in-addr.arpa
3.13.93.in-addr.arpa
4.13.93.in-addr.arpa
5.13.93.in-addr.arpa
6.13.93.in-addr.arpa
7.13.93.in-addr.arpa
8.13.93.in-addr.arpa
9.13.93.in-addr.arpa
10.13.93.in-addr.arpa
11.13.93.in-addr.arpa
12.13.93.in-addr.arpa
13.13.93.in-addr.arpa
14.13.93.in-addr.arpa
15.13.93.in-addr.arpa
and 48 more
/18 is not on a 8-bit boundary, so it takes 64 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011101.00001101.00000000.0000000093.13.0.0
Subnet mask11111111.11111111.11000000.00000000255.255.192.0
Network01011101.00001101.00000000.0000000093.13.0.0
Broadcast01011101.00001101.00111111.1111111193.13.63.255
Split into smaller subnets/28
/19 (2)/20 (4)/21 (8)/22 (16)/23 (32)/24 (64)/25 (128)/26 (256)/27 (512)/28 (1,024)/29 (2,048)/30 (4,096)

93.13.0.0/18 makes 1,024 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
193.13.0.0/2893.13.0.1 to 93.13.0.1493.13.0.1514
293.13.0.16/2893.13.0.17 to 93.13.0.3093.13.0.3114
393.13.0.32/2893.13.0.33 to 93.13.0.4693.13.0.4714
493.13.0.48/2893.13.0.49 to 93.13.0.6293.13.0.6314
593.13.0.64/2893.13.0.65 to 93.13.0.7893.13.0.7914
693.13.0.80/2893.13.0.81 to 93.13.0.9493.13.0.9514
793.13.0.96/2893.13.0.97 to 93.13.0.11093.13.0.11114
893.13.0.112/2893.13.0.113 to 93.13.0.12693.13.0.12714
993.13.0.128/2893.13.0.129 to 93.13.0.14293.13.0.14314
1093.13.0.144/2893.13.0.145 to 93.13.0.15893.13.0.15914
1193.13.0.160/2893.13.0.161 to 93.13.0.17493.13.0.17514
1293.13.0.176/2893.13.0.177 to 93.13.0.19093.13.0.19114
1393.13.0.192/2893.13.0.193 to 93.13.0.20693.13.0.20714
1493.13.0.208/2893.13.0.209 to 93.13.0.22293.13.0.22314
1593.13.0.224/2893.13.0.225 to 93.13.0.23893.13.0.23914
1693.13.0.240/2893.13.0.241 to 93.13.0.25493.13.0.25514
1793.13.1.0/2893.13.1.1 to 93.13.1.1493.13.1.1514
1893.13.1.16/2893.13.1.17 to 93.13.1.3093.13.1.3114
1993.13.1.32/2893.13.1.33 to 93.13.1.4693.13.1.4714
2093.13.1.48/2893.13.1.49 to 93.13.1.6293.13.1.6314
2193.13.1.64/2893.13.1.65 to 93.13.1.7893.13.1.7914
2293.13.1.80/2893.13.1.81 to 93.13.1.9493.13.1.9514
2393.13.1.96/2893.13.1.97 to 93.13.1.11093.13.1.11114
2493.13.1.112/2893.13.1.113 to 93.13.1.12693.13.1.12714
2593.13.1.128/2893.13.1.129 to 93.13.1.14293.13.1.14314
2693.13.1.144/2893.13.1.145 to 93.13.1.15893.13.1.15914
2793.13.1.160/2893.13.1.161 to 93.13.1.17493.13.1.17514
2893.13.1.176/2893.13.1.177 to 93.13.1.19093.13.1.19114
2993.13.1.192/2893.13.1.193 to 93.13.1.20693.13.1.20714
3093.13.1.208/2893.13.1.209 to 93.13.1.22293.13.1.22314
3193.13.1.224/2893.13.1.225 to 93.13.1.23893.13.1.23914
3293.13.1.240/2893.13.1.241 to 93.13.1.25493.13.1.25514
3393.13.2.0/2893.13.2.1 to 93.13.2.1493.13.2.1514
3493.13.2.16/2893.13.2.17 to 93.13.2.3093.13.2.3114
3593.13.2.32/2893.13.2.33 to 93.13.2.4693.13.2.4714
3693.13.2.48/2893.13.2.49 to 93.13.2.6293.13.2.6314
3793.13.2.64/2893.13.2.65 to 93.13.2.7893.13.2.7914
3893.13.2.80/2893.13.2.81 to 93.13.2.9493.13.2.9514
3993.13.2.96/2893.13.2.97 to 93.13.2.11093.13.2.11114
4093.13.2.112/2893.13.2.113 to 93.13.2.12693.13.2.12714
4193.13.2.128/2893.13.2.129 to 93.13.2.14293.13.2.14314
4293.13.2.144/2893.13.2.145 to 93.13.2.15893.13.2.15914
4393.13.2.160/2893.13.2.161 to 93.13.2.17493.13.2.17514
4493.13.2.176/2893.13.2.177 to 93.13.2.19093.13.2.19114
4593.13.2.192/2893.13.2.193 to 93.13.2.20693.13.2.20714
4693.13.2.208/2893.13.2.209 to 93.13.2.22293.13.2.22314
4793.13.2.224/2893.13.2.225 to 93.13.2.23893.13.2.23914
4893.13.2.240/2893.13.2.241 to 93.13.2.25493.13.2.25514
4993.13.3.0/2893.13.3.1 to 93.13.3.1493.13.3.1514
5093.13.3.16/2893.13.3.17 to 93.13.3.3093.13.3.3114
5193.13.3.32/2893.13.3.33 to 93.13.3.4693.13.3.4714
5293.13.3.48/2893.13.3.49 to 93.13.3.6293.13.3.6314
5393.13.3.64/2893.13.3.65 to 93.13.3.7893.13.3.7914
5493.13.3.80/2893.13.3.81 to 93.13.3.9493.13.3.9514
5593.13.3.96/2893.13.3.97 to 93.13.3.11093.13.3.11114
5693.13.3.112/2893.13.3.113 to 93.13.3.12693.13.3.12714
5793.13.3.128/2893.13.3.129 to 93.13.3.14293.13.3.14314
5893.13.3.144/2893.13.3.145 to 93.13.3.15893.13.3.15914
5993.13.3.160/2893.13.3.161 to 93.13.3.17493.13.3.17514
6093.13.3.176/2893.13.3.177 to 93.13.3.19093.13.3.19114
6193.13.3.192/2893.13.3.193 to 93.13.3.20693.13.3.20714
6293.13.3.208/2893.13.3.209 to 93.13.3.22293.13.3.22314
6393.13.3.224/2893.13.3.225 to 93.13.3.23893.13.3.23914
6493.13.3.240/2893.13.3.241 to 93.13.3.25493.13.3.25514
6593.13.4.0/2893.13.4.1 to 93.13.4.1493.13.4.1514
6693.13.4.16/2893.13.4.17 to 93.13.4.3093.13.4.3114
6793.13.4.32/2893.13.4.33 to 93.13.4.4693.13.4.4714
6893.13.4.48/2893.13.4.49 to 93.13.4.6293.13.4.6314
6993.13.4.64/2893.13.4.65 to 93.13.4.7893.13.4.7914
7093.13.4.80/2893.13.4.81 to 93.13.4.9493.13.4.9514
7193.13.4.96/2893.13.4.97 to 93.13.4.11093.13.4.11114
7293.13.4.112/2893.13.4.113 to 93.13.4.12693.13.4.12714
7393.13.4.128/2893.13.4.129 to 93.13.4.14293.13.4.14314
7493.13.4.144/2893.13.4.145 to 93.13.4.15893.13.4.15914
7593.13.4.160/2893.13.4.161 to 93.13.4.17493.13.4.17514
7693.13.4.176/2893.13.4.177 to 93.13.4.19093.13.4.19114
7793.13.4.192/2893.13.4.193 to 93.13.4.20693.13.4.20714
7893.13.4.208/2893.13.4.209 to 93.13.4.22293.13.4.22314
7993.13.4.224/2893.13.4.225 to 93.13.4.23893.13.4.23914
8093.13.4.240/2893.13.4.241 to 93.13.4.25493.13.4.25514
8193.13.5.0/2893.13.5.1 to 93.13.5.1493.13.5.1514
8293.13.5.16/2893.13.5.17 to 93.13.5.3093.13.5.3114
8393.13.5.32/2893.13.5.33 to 93.13.5.4693.13.5.4714
8493.13.5.48/2893.13.5.49 to 93.13.5.6293.13.5.6314
8593.13.5.64/2893.13.5.65 to 93.13.5.7893.13.5.7914
8693.13.5.80/2893.13.5.81 to 93.13.5.9493.13.5.9514
8793.13.5.96/2893.13.5.97 to 93.13.5.11093.13.5.11114
8893.13.5.112/2893.13.5.113 to 93.13.5.12693.13.5.12714
8993.13.5.128/2893.13.5.129 to 93.13.5.14293.13.5.14314
9093.13.5.144/2893.13.5.145 to 93.13.5.15893.13.5.15914
9193.13.5.160/2893.13.5.161 to 93.13.5.17493.13.5.17514
9293.13.5.176/2893.13.5.177 to 93.13.5.19093.13.5.19114
9393.13.5.192/2893.13.5.193 to 93.13.5.20693.13.5.20714
9493.13.5.208/2893.13.5.209 to 93.13.5.22293.13.5.22314
9593.13.5.224/2893.13.5.225 to 93.13.5.23893.13.5.23914
9693.13.5.240/2893.13.5.241 to 93.13.5.25493.13.5.25514
9793.13.6.0/2893.13.6.1 to 93.13.6.1493.13.6.1514
9893.13.6.16/2893.13.6.17 to 93.13.6.3093.13.6.3114
9993.13.6.32/2893.13.6.33 to 93.13.6.4693.13.6.4714
10093.13.6.48/2893.13.6.49 to 93.13.6.6293.13.6.6314
10193.13.6.64/2893.13.6.65 to 93.13.6.7893.13.6.7914
10293.13.6.80/2893.13.6.81 to 93.13.6.9493.13.6.9514
10393.13.6.96/2893.13.6.97 to 93.13.6.11093.13.6.11114
10493.13.6.112/2893.13.6.113 to 93.13.6.12693.13.6.12714
10593.13.6.128/2893.13.6.129 to 93.13.6.14293.13.6.14314
10693.13.6.144/2893.13.6.145 to 93.13.6.15893.13.6.15914
10793.13.6.160/2893.13.6.161 to 93.13.6.17493.13.6.17514
10893.13.6.176/2893.13.6.177 to 93.13.6.19093.13.6.19114
10993.13.6.192/2893.13.6.193 to 93.13.6.20693.13.6.20714
11093.13.6.208/2893.13.6.209 to 93.13.6.22293.13.6.22314
11193.13.6.224/2893.13.6.225 to 93.13.6.23893.13.6.23914
11293.13.6.240/2893.13.6.241 to 93.13.6.25493.13.6.25514
11393.13.7.0/2893.13.7.1 to 93.13.7.1493.13.7.1514
11493.13.7.16/2893.13.7.17 to 93.13.7.3093.13.7.3114
11593.13.7.32/2893.13.7.33 to 93.13.7.4693.13.7.4714
11693.13.7.48/2893.13.7.49 to 93.13.7.6293.13.7.6314
11793.13.7.64/2893.13.7.65 to 93.13.7.7893.13.7.7914
11893.13.7.80/2893.13.7.81 to 93.13.7.9493.13.7.9514
11993.13.7.96/2893.13.7.97 to 93.13.7.11093.13.7.11114
12093.13.7.112/2893.13.7.113 to 93.13.7.12693.13.7.12714
12193.13.7.128/2893.13.7.129 to 93.13.7.14293.13.7.14314
12293.13.7.144/2893.13.7.145 to 93.13.7.15893.13.7.15914
12393.13.7.160/2893.13.7.161 to 93.13.7.17493.13.7.17514
12493.13.7.176/2893.13.7.177 to 93.13.7.19093.13.7.19114
12593.13.7.192/2893.13.7.193 to 93.13.7.20693.13.7.20714
12693.13.7.208/2893.13.7.209 to 93.13.7.22293.13.7.22314
12793.13.7.224/2893.13.7.225 to 93.13.7.23893.13.7.23914
12893.13.7.240/2893.13.7.241 to 93.13.7.25493.13.7.25514
12993.13.8.0/2893.13.8.1 to 93.13.8.1493.13.8.1514
13093.13.8.16/2893.13.8.17 to 93.13.8.3093.13.8.3114
13193.13.8.32/2893.13.8.33 to 93.13.8.4693.13.8.4714
13293.13.8.48/2893.13.8.49 to 93.13.8.6293.13.8.6314
13393.13.8.64/2893.13.8.65 to 93.13.8.7893.13.8.7914
13493.13.8.80/2893.13.8.81 to 93.13.8.9493.13.8.9514
13593.13.8.96/2893.13.8.97 to 93.13.8.11093.13.8.11114
13693.13.8.112/2893.13.8.113 to 93.13.8.12693.13.8.12714
13793.13.8.128/2893.13.8.129 to 93.13.8.14293.13.8.14314
13893.13.8.144/2893.13.8.145 to 93.13.8.15893.13.8.15914
13993.13.8.160/2893.13.8.161 to 93.13.8.17493.13.8.17514
14093.13.8.176/2893.13.8.177 to 93.13.8.19093.13.8.19114
14193.13.8.192/2893.13.8.193 to 93.13.8.20693.13.8.20714
14293.13.8.208/2893.13.8.209 to 93.13.8.22293.13.8.22314
14393.13.8.224/2893.13.8.225 to 93.13.8.23893.13.8.23914
14493.13.8.240/2893.13.8.241 to 93.13.8.25493.13.8.25514
14593.13.9.0/2893.13.9.1 to 93.13.9.1493.13.9.1514
14693.13.9.16/2893.13.9.17 to 93.13.9.3093.13.9.3114
14793.13.9.32/2893.13.9.33 to 93.13.9.4693.13.9.4714
14893.13.9.48/2893.13.9.49 to 93.13.9.6293.13.9.6314
14993.13.9.64/2893.13.9.65 to 93.13.9.7893.13.9.7914
15093.13.9.80/2893.13.9.81 to 93.13.9.9493.13.9.9514
15193.13.9.96/2893.13.9.97 to 93.13.9.11093.13.9.11114
15293.13.9.112/2893.13.9.113 to 93.13.9.12693.13.9.12714
15393.13.9.128/2893.13.9.129 to 93.13.9.14293.13.9.14314
15493.13.9.144/2893.13.9.145 to 93.13.9.15893.13.9.15914
15593.13.9.160/2893.13.9.161 to 93.13.9.17493.13.9.17514
15693.13.9.176/2893.13.9.177 to 93.13.9.19093.13.9.19114
15793.13.9.192/2893.13.9.193 to 93.13.9.20693.13.9.20714
15893.13.9.208/2893.13.9.209 to 93.13.9.22293.13.9.22314
15993.13.9.224/2893.13.9.225 to 93.13.9.23893.13.9.23914
16093.13.9.240/2893.13.9.241 to 93.13.9.25493.13.9.25514
16193.13.10.0/2893.13.10.1 to 93.13.10.1493.13.10.1514
16293.13.10.16/2893.13.10.17 to 93.13.10.3093.13.10.3114
16393.13.10.32/2893.13.10.33 to 93.13.10.4693.13.10.4714
16493.13.10.48/2893.13.10.49 to 93.13.10.6293.13.10.6314
16593.13.10.64/2893.13.10.65 to 93.13.10.7893.13.10.7914
16693.13.10.80/2893.13.10.81 to 93.13.10.9493.13.10.9514
16793.13.10.96/2893.13.10.97 to 93.13.10.11093.13.10.11114
16893.13.10.112/2893.13.10.113 to 93.13.10.12693.13.10.12714
16993.13.10.128/2893.13.10.129 to 93.13.10.14293.13.10.14314
17093.13.10.144/2893.13.10.145 to 93.13.10.15893.13.10.15914
17193.13.10.160/2893.13.10.161 to 93.13.10.17493.13.10.17514
17293.13.10.176/2893.13.10.177 to 93.13.10.19093.13.10.19114
17393.13.10.192/2893.13.10.193 to 93.13.10.20693.13.10.20714
17493.13.10.208/2893.13.10.209 to 93.13.10.22293.13.10.22314
17593.13.10.224/2893.13.10.225 to 93.13.10.23893.13.10.23914
17693.13.10.240/2893.13.10.241 to 93.13.10.25493.13.10.25514
17793.13.11.0/2893.13.11.1 to 93.13.11.1493.13.11.1514
17893.13.11.16/2893.13.11.17 to 93.13.11.3093.13.11.3114
17993.13.11.32/2893.13.11.33 to 93.13.11.4693.13.11.4714
18093.13.11.48/2893.13.11.49 to 93.13.11.6293.13.11.6314
18193.13.11.64/2893.13.11.65 to 93.13.11.7893.13.11.7914
18293.13.11.80/2893.13.11.81 to 93.13.11.9493.13.11.9514
18393.13.11.96/2893.13.11.97 to 93.13.11.11093.13.11.11114
18493.13.11.112/2893.13.11.113 to 93.13.11.12693.13.11.12714
18593.13.11.128/2893.13.11.129 to 93.13.11.14293.13.11.14314
18693.13.11.144/2893.13.11.145 to 93.13.11.15893.13.11.15914
18793.13.11.160/2893.13.11.161 to 93.13.11.17493.13.11.17514
18893.13.11.176/2893.13.11.177 to 93.13.11.19093.13.11.19114
18993.13.11.192/2893.13.11.193 to 93.13.11.20693.13.11.20714
19093.13.11.208/2893.13.11.209 to 93.13.11.22293.13.11.22314
19193.13.11.224/2893.13.11.225 to 93.13.11.23893.13.11.23914
19293.13.11.240/2893.13.11.241 to 93.13.11.25493.13.11.25514
19393.13.12.0/2893.13.12.1 to 93.13.12.1493.13.12.1514
19493.13.12.16/2893.13.12.17 to 93.13.12.3093.13.12.3114
19593.13.12.32/2893.13.12.33 to 93.13.12.4693.13.12.4714
19693.13.12.48/2893.13.12.49 to 93.13.12.6293.13.12.6314
19793.13.12.64/2893.13.12.65 to 93.13.12.7893.13.12.7914
19893.13.12.80/2893.13.12.81 to 93.13.12.9493.13.12.9514
19993.13.12.96/2893.13.12.97 to 93.13.12.11093.13.12.11114
20093.13.12.112/2893.13.12.113 to 93.13.12.12693.13.12.12714
20193.13.12.128/2893.13.12.129 to 93.13.12.14293.13.12.14314
20293.13.12.144/2893.13.12.145 to 93.13.12.15893.13.12.15914
20393.13.12.160/2893.13.12.161 to 93.13.12.17493.13.12.17514
20493.13.12.176/2893.13.12.177 to 93.13.12.19093.13.12.19114
20593.13.12.192/2893.13.12.193 to 93.13.12.20693.13.12.20714
20693.13.12.208/2893.13.12.209 to 93.13.12.22293.13.12.22314
20793.13.12.224/2893.13.12.225 to 93.13.12.23893.13.12.23914
20893.13.12.240/2893.13.12.241 to 93.13.12.25493.13.12.25514
20993.13.13.0/2893.13.13.1 to 93.13.13.1493.13.13.1514
21093.13.13.16/2893.13.13.17 to 93.13.13.3093.13.13.3114
21193.13.13.32/2893.13.13.33 to 93.13.13.4693.13.13.4714
21293.13.13.48/2893.13.13.49 to 93.13.13.6293.13.13.6314
21393.13.13.64/2893.13.13.65 to 93.13.13.7893.13.13.7914
21493.13.13.80/2893.13.13.81 to 93.13.13.9493.13.13.9514
21593.13.13.96/2893.13.13.97 to 93.13.13.11093.13.13.11114
21693.13.13.112/2893.13.13.113 to 93.13.13.12693.13.13.12714
21793.13.13.128/2893.13.13.129 to 93.13.13.14293.13.13.14314
21893.13.13.144/2893.13.13.145 to 93.13.13.15893.13.13.15914
21993.13.13.160/2893.13.13.161 to 93.13.13.17493.13.13.17514
22093.13.13.176/2893.13.13.177 to 93.13.13.19093.13.13.19114
22193.13.13.192/2893.13.13.193 to 93.13.13.20693.13.13.20714
22293.13.13.208/2893.13.13.209 to 93.13.13.22293.13.13.22314
22393.13.13.224/2893.13.13.225 to 93.13.13.23893.13.13.23914
22493.13.13.240/2893.13.13.241 to 93.13.13.25493.13.13.25514
22593.13.14.0/2893.13.14.1 to 93.13.14.1493.13.14.1514
22693.13.14.16/2893.13.14.17 to 93.13.14.3093.13.14.3114
22793.13.14.32/2893.13.14.33 to 93.13.14.4693.13.14.4714
22893.13.14.48/2893.13.14.49 to 93.13.14.6293.13.14.6314
22993.13.14.64/2893.13.14.65 to 93.13.14.7893.13.14.7914
23093.13.14.80/2893.13.14.81 to 93.13.14.9493.13.14.9514
23193.13.14.96/2893.13.14.97 to 93.13.14.11093.13.14.11114
23293.13.14.112/2893.13.14.113 to 93.13.14.12693.13.14.12714
23393.13.14.128/2893.13.14.129 to 93.13.14.14293.13.14.14314
23493.13.14.144/2893.13.14.145 to 93.13.14.15893.13.14.15914
23593.13.14.160/2893.13.14.161 to 93.13.14.17493.13.14.17514
23693.13.14.176/2893.13.14.177 to 93.13.14.19093.13.14.19114
23793.13.14.192/2893.13.14.193 to 93.13.14.20693.13.14.20714
23893.13.14.208/2893.13.14.209 to 93.13.14.22293.13.14.22314
23993.13.14.224/2893.13.14.225 to 93.13.14.23893.13.14.23914
24093.13.14.240/2893.13.14.241 to 93.13.14.25493.13.14.25514
24193.13.15.0/2893.13.15.1 to 93.13.15.1493.13.15.1514
24293.13.15.16/2893.13.15.17 to 93.13.15.3093.13.15.3114
24393.13.15.32/2893.13.15.33 to 93.13.15.4693.13.15.4714
24493.13.15.48/2893.13.15.49 to 93.13.15.6293.13.15.6314
24593.13.15.64/2893.13.15.65 to 93.13.15.7893.13.15.7914
24693.13.15.80/2893.13.15.81 to 93.13.15.9493.13.15.9514
24793.13.15.96/2893.13.15.97 to 93.13.15.11093.13.15.11114
24893.13.15.112/2893.13.15.113 to 93.13.15.12693.13.15.12714
24993.13.15.128/2893.13.15.129 to 93.13.15.14293.13.15.14314
25093.13.15.144/2893.13.15.145 to 93.13.15.15893.13.15.15914
25193.13.15.160/2893.13.15.161 to 93.13.15.17493.13.15.17514
25293.13.15.176/2893.13.15.177 to 93.13.15.19093.13.15.19114
25393.13.15.192/2893.13.15.193 to 93.13.15.20693.13.15.20714
25493.13.15.208/2893.13.15.209 to 93.13.15.22293.13.15.22314
25593.13.15.224/2893.13.15.225 to 93.13.15.23893.13.15.23914
25693.13.15.240/2893.13.15.241 to 93.13.15.25493.13.15.25514

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.