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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.

Network14.87.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
14.87.0.0
Broadcast address
14.87.255.255
First usable
14.87.0.1
Last usable
14.87.255.254
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 0E570000 · Integer 240582656 to 240648191
Reverse DNS zone
87.14.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001110.01010111..00000000.0000000014.87.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00001110.01010111..00000000.0000000014.87.0.0
Broadcast00001110.01010111..11111111.1111111114.87.255.255
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)

14.87.0.0/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
114.87.0.0/2814.87.0.1 to 14.87.0.1414.87.0.1514
214.87.0.16/2814.87.0.17 to 14.87.0.3014.87.0.3114
314.87.0.32/2814.87.0.33 to 14.87.0.4614.87.0.4714
414.87.0.48/2814.87.0.49 to 14.87.0.6214.87.0.6314
514.87.0.64/2814.87.0.65 to 14.87.0.7814.87.0.7914
614.87.0.80/2814.87.0.81 to 14.87.0.9414.87.0.9514
714.87.0.96/2814.87.0.97 to 14.87.0.11014.87.0.11114
814.87.0.112/2814.87.0.113 to 14.87.0.12614.87.0.12714
914.87.0.128/2814.87.0.129 to 14.87.0.14214.87.0.14314
1014.87.0.144/2814.87.0.145 to 14.87.0.15814.87.0.15914
1114.87.0.160/2814.87.0.161 to 14.87.0.17414.87.0.17514
1214.87.0.176/2814.87.0.177 to 14.87.0.19014.87.0.19114
1314.87.0.192/2814.87.0.193 to 14.87.0.20614.87.0.20714
1414.87.0.208/2814.87.0.209 to 14.87.0.22214.87.0.22314
1514.87.0.224/2814.87.0.225 to 14.87.0.23814.87.0.23914
1614.87.0.240/2814.87.0.241 to 14.87.0.25414.87.0.25514
1714.87.1.0/2814.87.1.1 to 14.87.1.1414.87.1.1514
1814.87.1.16/2814.87.1.17 to 14.87.1.3014.87.1.3114
1914.87.1.32/2814.87.1.33 to 14.87.1.4614.87.1.4714
2014.87.1.48/2814.87.1.49 to 14.87.1.6214.87.1.6314
2114.87.1.64/2814.87.1.65 to 14.87.1.7814.87.1.7914
2214.87.1.80/2814.87.1.81 to 14.87.1.9414.87.1.9514
2314.87.1.96/2814.87.1.97 to 14.87.1.11014.87.1.11114
2414.87.1.112/2814.87.1.113 to 14.87.1.12614.87.1.12714
2514.87.1.128/2814.87.1.129 to 14.87.1.14214.87.1.14314
2614.87.1.144/2814.87.1.145 to 14.87.1.15814.87.1.15914
2714.87.1.160/2814.87.1.161 to 14.87.1.17414.87.1.17514
2814.87.1.176/2814.87.1.177 to 14.87.1.19014.87.1.19114
2914.87.1.192/2814.87.1.193 to 14.87.1.20614.87.1.20714
3014.87.1.208/2814.87.1.209 to 14.87.1.22214.87.1.22314
3114.87.1.224/2814.87.1.225 to 14.87.1.23814.87.1.23914
3214.87.1.240/2814.87.1.241 to 14.87.1.25414.87.1.25514
3314.87.2.0/2814.87.2.1 to 14.87.2.1414.87.2.1514
3414.87.2.16/2814.87.2.17 to 14.87.2.3014.87.2.3114
3514.87.2.32/2814.87.2.33 to 14.87.2.4614.87.2.4714
3614.87.2.48/2814.87.2.49 to 14.87.2.6214.87.2.6314
3714.87.2.64/2814.87.2.65 to 14.87.2.7814.87.2.7914
3814.87.2.80/2814.87.2.81 to 14.87.2.9414.87.2.9514
3914.87.2.96/2814.87.2.97 to 14.87.2.11014.87.2.11114
4014.87.2.112/2814.87.2.113 to 14.87.2.12614.87.2.12714
4114.87.2.128/2814.87.2.129 to 14.87.2.14214.87.2.14314
4214.87.2.144/2814.87.2.145 to 14.87.2.15814.87.2.15914
4314.87.2.160/2814.87.2.161 to 14.87.2.17414.87.2.17514
4414.87.2.176/2814.87.2.177 to 14.87.2.19014.87.2.19114
4514.87.2.192/2814.87.2.193 to 14.87.2.20614.87.2.20714
4614.87.2.208/2814.87.2.209 to 14.87.2.22214.87.2.22314
4714.87.2.224/2814.87.2.225 to 14.87.2.23814.87.2.23914
4814.87.2.240/2814.87.2.241 to 14.87.2.25414.87.2.25514
4914.87.3.0/2814.87.3.1 to 14.87.3.1414.87.3.1514
5014.87.3.16/2814.87.3.17 to 14.87.3.3014.87.3.3114
5114.87.3.32/2814.87.3.33 to 14.87.3.4614.87.3.4714
5214.87.3.48/2814.87.3.49 to 14.87.3.6214.87.3.6314
5314.87.3.64/2814.87.3.65 to 14.87.3.7814.87.3.7914
5414.87.3.80/2814.87.3.81 to 14.87.3.9414.87.3.9514
5514.87.3.96/2814.87.3.97 to 14.87.3.11014.87.3.11114
5614.87.3.112/2814.87.3.113 to 14.87.3.12614.87.3.12714
5714.87.3.128/2814.87.3.129 to 14.87.3.14214.87.3.14314
5814.87.3.144/2814.87.3.145 to 14.87.3.15814.87.3.15914
5914.87.3.160/2814.87.3.161 to 14.87.3.17414.87.3.17514
6014.87.3.176/2814.87.3.177 to 14.87.3.19014.87.3.19114
6114.87.3.192/2814.87.3.193 to 14.87.3.20614.87.3.20714
6214.87.3.208/2814.87.3.209 to 14.87.3.22214.87.3.22314
6314.87.3.224/2814.87.3.225 to 14.87.3.23814.87.3.23914
6414.87.3.240/2814.87.3.241 to 14.87.3.25414.87.3.25514
6514.87.4.0/2814.87.4.1 to 14.87.4.1414.87.4.1514
6614.87.4.16/2814.87.4.17 to 14.87.4.3014.87.4.3114
6714.87.4.32/2814.87.4.33 to 14.87.4.4614.87.4.4714
6814.87.4.48/2814.87.4.49 to 14.87.4.6214.87.4.6314
6914.87.4.64/2814.87.4.65 to 14.87.4.7814.87.4.7914
7014.87.4.80/2814.87.4.81 to 14.87.4.9414.87.4.9514
7114.87.4.96/2814.87.4.97 to 14.87.4.11014.87.4.11114
7214.87.4.112/2814.87.4.113 to 14.87.4.12614.87.4.12714
7314.87.4.128/2814.87.4.129 to 14.87.4.14214.87.4.14314
7414.87.4.144/2814.87.4.145 to 14.87.4.15814.87.4.15914
7514.87.4.160/2814.87.4.161 to 14.87.4.17414.87.4.17514
7614.87.4.176/2814.87.4.177 to 14.87.4.19014.87.4.19114
7714.87.4.192/2814.87.4.193 to 14.87.4.20614.87.4.20714
7814.87.4.208/2814.87.4.209 to 14.87.4.22214.87.4.22314
7914.87.4.224/2814.87.4.225 to 14.87.4.23814.87.4.23914
8014.87.4.240/2814.87.4.241 to 14.87.4.25414.87.4.25514
8114.87.5.0/2814.87.5.1 to 14.87.5.1414.87.5.1514
8214.87.5.16/2814.87.5.17 to 14.87.5.3014.87.5.3114
8314.87.5.32/2814.87.5.33 to 14.87.5.4614.87.5.4714
8414.87.5.48/2814.87.5.49 to 14.87.5.6214.87.5.6314
8514.87.5.64/2814.87.5.65 to 14.87.5.7814.87.5.7914
8614.87.5.80/2814.87.5.81 to 14.87.5.9414.87.5.9514
8714.87.5.96/2814.87.5.97 to 14.87.5.11014.87.5.11114
8814.87.5.112/2814.87.5.113 to 14.87.5.12614.87.5.12714
8914.87.5.128/2814.87.5.129 to 14.87.5.14214.87.5.14314
9014.87.5.144/2814.87.5.145 to 14.87.5.15814.87.5.15914
9114.87.5.160/2814.87.5.161 to 14.87.5.17414.87.5.17514
9214.87.5.176/2814.87.5.177 to 14.87.5.19014.87.5.19114
9314.87.5.192/2814.87.5.193 to 14.87.5.20614.87.5.20714
9414.87.5.208/2814.87.5.209 to 14.87.5.22214.87.5.22314
9514.87.5.224/2814.87.5.225 to 14.87.5.23814.87.5.23914
9614.87.5.240/2814.87.5.241 to 14.87.5.25414.87.5.25514
9714.87.6.0/2814.87.6.1 to 14.87.6.1414.87.6.1514
9814.87.6.16/2814.87.6.17 to 14.87.6.3014.87.6.3114
9914.87.6.32/2814.87.6.33 to 14.87.6.4614.87.6.4714
10014.87.6.48/2814.87.6.49 to 14.87.6.6214.87.6.6314
10114.87.6.64/2814.87.6.65 to 14.87.6.7814.87.6.7914
10214.87.6.80/2814.87.6.81 to 14.87.6.9414.87.6.9514
10314.87.6.96/2814.87.6.97 to 14.87.6.11014.87.6.11114
10414.87.6.112/2814.87.6.113 to 14.87.6.12614.87.6.12714
10514.87.6.128/2814.87.6.129 to 14.87.6.14214.87.6.14314
10614.87.6.144/2814.87.6.145 to 14.87.6.15814.87.6.15914
10714.87.6.160/2814.87.6.161 to 14.87.6.17414.87.6.17514
10814.87.6.176/2814.87.6.177 to 14.87.6.19014.87.6.19114
10914.87.6.192/2814.87.6.193 to 14.87.6.20614.87.6.20714
11014.87.6.208/2814.87.6.209 to 14.87.6.22214.87.6.22314
11114.87.6.224/2814.87.6.225 to 14.87.6.23814.87.6.23914
11214.87.6.240/2814.87.6.241 to 14.87.6.25414.87.6.25514
11314.87.7.0/2814.87.7.1 to 14.87.7.1414.87.7.1514
11414.87.7.16/2814.87.7.17 to 14.87.7.3014.87.7.3114
11514.87.7.32/2814.87.7.33 to 14.87.7.4614.87.7.4714
11614.87.7.48/2814.87.7.49 to 14.87.7.6214.87.7.6314
11714.87.7.64/2814.87.7.65 to 14.87.7.7814.87.7.7914
11814.87.7.80/2814.87.7.81 to 14.87.7.9414.87.7.9514
11914.87.7.96/2814.87.7.97 to 14.87.7.11014.87.7.11114
12014.87.7.112/2814.87.7.113 to 14.87.7.12614.87.7.12714
12114.87.7.128/2814.87.7.129 to 14.87.7.14214.87.7.14314
12214.87.7.144/2814.87.7.145 to 14.87.7.15814.87.7.15914
12314.87.7.160/2814.87.7.161 to 14.87.7.17414.87.7.17514
12414.87.7.176/2814.87.7.177 to 14.87.7.19014.87.7.19114
12514.87.7.192/2814.87.7.193 to 14.87.7.20614.87.7.20714
12614.87.7.208/2814.87.7.209 to 14.87.7.22214.87.7.22314
12714.87.7.224/2814.87.7.225 to 14.87.7.23814.87.7.23914
12814.87.7.240/2814.87.7.241 to 14.87.7.25414.87.7.25514
12914.87.8.0/2814.87.8.1 to 14.87.8.1414.87.8.1514
13014.87.8.16/2814.87.8.17 to 14.87.8.3014.87.8.3114
13114.87.8.32/2814.87.8.33 to 14.87.8.4614.87.8.4714
13214.87.8.48/2814.87.8.49 to 14.87.8.6214.87.8.6314
13314.87.8.64/2814.87.8.65 to 14.87.8.7814.87.8.7914
13414.87.8.80/2814.87.8.81 to 14.87.8.9414.87.8.9514
13514.87.8.96/2814.87.8.97 to 14.87.8.11014.87.8.11114
13614.87.8.112/2814.87.8.113 to 14.87.8.12614.87.8.12714
13714.87.8.128/2814.87.8.129 to 14.87.8.14214.87.8.14314
13814.87.8.144/2814.87.8.145 to 14.87.8.15814.87.8.15914
13914.87.8.160/2814.87.8.161 to 14.87.8.17414.87.8.17514
14014.87.8.176/2814.87.8.177 to 14.87.8.19014.87.8.19114
14114.87.8.192/2814.87.8.193 to 14.87.8.20614.87.8.20714
14214.87.8.208/2814.87.8.209 to 14.87.8.22214.87.8.22314
14314.87.8.224/2814.87.8.225 to 14.87.8.23814.87.8.23914
14414.87.8.240/2814.87.8.241 to 14.87.8.25414.87.8.25514
14514.87.9.0/2814.87.9.1 to 14.87.9.1414.87.9.1514
14614.87.9.16/2814.87.9.17 to 14.87.9.3014.87.9.3114
14714.87.9.32/2814.87.9.33 to 14.87.9.4614.87.9.4714
14814.87.9.48/2814.87.9.49 to 14.87.9.6214.87.9.6314
14914.87.9.64/2814.87.9.65 to 14.87.9.7814.87.9.7914
15014.87.9.80/2814.87.9.81 to 14.87.9.9414.87.9.9514
15114.87.9.96/2814.87.9.97 to 14.87.9.11014.87.9.11114
15214.87.9.112/2814.87.9.113 to 14.87.9.12614.87.9.12714
15314.87.9.128/2814.87.9.129 to 14.87.9.14214.87.9.14314
15414.87.9.144/2814.87.9.145 to 14.87.9.15814.87.9.15914
15514.87.9.160/2814.87.9.161 to 14.87.9.17414.87.9.17514
15614.87.9.176/2814.87.9.177 to 14.87.9.19014.87.9.19114
15714.87.9.192/2814.87.9.193 to 14.87.9.20614.87.9.20714
15814.87.9.208/2814.87.9.209 to 14.87.9.22214.87.9.22314
15914.87.9.224/2814.87.9.225 to 14.87.9.23814.87.9.23914
16014.87.9.240/2814.87.9.241 to 14.87.9.25414.87.9.25514
16114.87.10.0/2814.87.10.1 to 14.87.10.1414.87.10.1514
16214.87.10.16/2814.87.10.17 to 14.87.10.3014.87.10.3114
16314.87.10.32/2814.87.10.33 to 14.87.10.4614.87.10.4714
16414.87.10.48/2814.87.10.49 to 14.87.10.6214.87.10.6314
16514.87.10.64/2814.87.10.65 to 14.87.10.7814.87.10.7914
16614.87.10.80/2814.87.10.81 to 14.87.10.9414.87.10.9514
16714.87.10.96/2814.87.10.97 to 14.87.10.11014.87.10.11114
16814.87.10.112/2814.87.10.113 to 14.87.10.12614.87.10.12714
16914.87.10.128/2814.87.10.129 to 14.87.10.14214.87.10.14314
17014.87.10.144/2814.87.10.145 to 14.87.10.15814.87.10.15914
17114.87.10.160/2814.87.10.161 to 14.87.10.17414.87.10.17514
17214.87.10.176/2814.87.10.177 to 14.87.10.19014.87.10.19114
17314.87.10.192/2814.87.10.193 to 14.87.10.20614.87.10.20714
17414.87.10.208/2814.87.10.209 to 14.87.10.22214.87.10.22314
17514.87.10.224/2814.87.10.225 to 14.87.10.23814.87.10.23914
17614.87.10.240/2814.87.10.241 to 14.87.10.25414.87.10.25514
17714.87.11.0/2814.87.11.1 to 14.87.11.1414.87.11.1514
17814.87.11.16/2814.87.11.17 to 14.87.11.3014.87.11.3114
17914.87.11.32/2814.87.11.33 to 14.87.11.4614.87.11.4714
18014.87.11.48/2814.87.11.49 to 14.87.11.6214.87.11.6314
18114.87.11.64/2814.87.11.65 to 14.87.11.7814.87.11.7914
18214.87.11.80/2814.87.11.81 to 14.87.11.9414.87.11.9514
18314.87.11.96/2814.87.11.97 to 14.87.11.11014.87.11.11114
18414.87.11.112/2814.87.11.113 to 14.87.11.12614.87.11.12714
18514.87.11.128/2814.87.11.129 to 14.87.11.14214.87.11.14314
18614.87.11.144/2814.87.11.145 to 14.87.11.15814.87.11.15914
18714.87.11.160/2814.87.11.161 to 14.87.11.17414.87.11.17514
18814.87.11.176/2814.87.11.177 to 14.87.11.19014.87.11.19114
18914.87.11.192/2814.87.11.193 to 14.87.11.20614.87.11.20714
19014.87.11.208/2814.87.11.209 to 14.87.11.22214.87.11.22314
19114.87.11.224/2814.87.11.225 to 14.87.11.23814.87.11.23914
19214.87.11.240/2814.87.11.241 to 14.87.11.25414.87.11.25514
19314.87.12.0/2814.87.12.1 to 14.87.12.1414.87.12.1514
19414.87.12.16/2814.87.12.17 to 14.87.12.3014.87.12.3114
19514.87.12.32/2814.87.12.33 to 14.87.12.4614.87.12.4714
19614.87.12.48/2814.87.12.49 to 14.87.12.6214.87.12.6314
19714.87.12.64/2814.87.12.65 to 14.87.12.7814.87.12.7914
19814.87.12.80/2814.87.12.81 to 14.87.12.9414.87.12.9514
19914.87.12.96/2814.87.12.97 to 14.87.12.11014.87.12.11114
20014.87.12.112/2814.87.12.113 to 14.87.12.12614.87.12.12714
20114.87.12.128/2814.87.12.129 to 14.87.12.14214.87.12.14314
20214.87.12.144/2814.87.12.145 to 14.87.12.15814.87.12.15914
20314.87.12.160/2814.87.12.161 to 14.87.12.17414.87.12.17514
20414.87.12.176/2814.87.12.177 to 14.87.12.19014.87.12.19114
20514.87.12.192/2814.87.12.193 to 14.87.12.20614.87.12.20714
20614.87.12.208/2814.87.12.209 to 14.87.12.22214.87.12.22314
20714.87.12.224/2814.87.12.225 to 14.87.12.23814.87.12.23914
20814.87.12.240/2814.87.12.241 to 14.87.12.25414.87.12.25514
20914.87.13.0/2814.87.13.1 to 14.87.13.1414.87.13.1514
21014.87.13.16/2814.87.13.17 to 14.87.13.3014.87.13.3114
21114.87.13.32/2814.87.13.33 to 14.87.13.4614.87.13.4714
21214.87.13.48/2814.87.13.49 to 14.87.13.6214.87.13.6314
21314.87.13.64/2814.87.13.65 to 14.87.13.7814.87.13.7914
21414.87.13.80/2814.87.13.81 to 14.87.13.9414.87.13.9514
21514.87.13.96/2814.87.13.97 to 14.87.13.11014.87.13.11114
21614.87.13.112/2814.87.13.113 to 14.87.13.12614.87.13.12714
21714.87.13.128/2814.87.13.129 to 14.87.13.14214.87.13.14314
21814.87.13.144/2814.87.13.145 to 14.87.13.15814.87.13.15914
21914.87.13.160/2814.87.13.161 to 14.87.13.17414.87.13.17514
22014.87.13.176/2814.87.13.177 to 14.87.13.19014.87.13.19114
22114.87.13.192/2814.87.13.193 to 14.87.13.20614.87.13.20714
22214.87.13.208/2814.87.13.209 to 14.87.13.22214.87.13.22314
22314.87.13.224/2814.87.13.225 to 14.87.13.23814.87.13.23914
22414.87.13.240/2814.87.13.241 to 14.87.13.25414.87.13.25514
22514.87.14.0/2814.87.14.1 to 14.87.14.1414.87.14.1514
22614.87.14.16/2814.87.14.17 to 14.87.14.3014.87.14.3114
22714.87.14.32/2814.87.14.33 to 14.87.14.4614.87.14.4714
22814.87.14.48/2814.87.14.49 to 14.87.14.6214.87.14.6314
22914.87.14.64/2814.87.14.65 to 14.87.14.7814.87.14.7914
23014.87.14.80/2814.87.14.81 to 14.87.14.9414.87.14.9514
23114.87.14.96/2814.87.14.97 to 14.87.14.11014.87.14.11114
23214.87.14.112/2814.87.14.113 to 14.87.14.12614.87.14.12714
23314.87.14.128/2814.87.14.129 to 14.87.14.14214.87.14.14314
23414.87.14.144/2814.87.14.145 to 14.87.14.15814.87.14.15914
23514.87.14.160/2814.87.14.161 to 14.87.14.17414.87.14.17514
23614.87.14.176/2814.87.14.177 to 14.87.14.19014.87.14.19114
23714.87.14.192/2814.87.14.193 to 14.87.14.20614.87.14.20714
23814.87.14.208/2814.87.14.209 to 14.87.14.22214.87.14.22314
23914.87.14.224/2814.87.14.225 to 14.87.14.23814.87.14.23914
24014.87.14.240/2814.87.14.241 to 14.87.14.25414.87.14.25514
24114.87.15.0/2814.87.15.1 to 14.87.15.1414.87.15.1514
24214.87.15.16/2814.87.15.17 to 14.87.15.3014.87.15.3114
24314.87.15.32/2814.87.15.33 to 14.87.15.4614.87.15.4714
24414.87.15.48/2814.87.15.49 to 14.87.15.6214.87.15.6314
24514.87.15.64/2814.87.15.65 to 14.87.15.7814.87.15.7914
24614.87.15.80/2814.87.15.81 to 14.87.15.9414.87.15.9514
24714.87.15.96/2814.87.15.97 to 14.87.15.11014.87.15.11114
24814.87.15.112/2814.87.15.113 to 14.87.15.12614.87.15.12714
24914.87.15.128/2814.87.15.129 to 14.87.15.14214.87.15.14314
25014.87.15.144/2814.87.15.145 to 14.87.15.15814.87.15.15914
25114.87.15.160/2814.87.15.161 to 14.87.15.17414.87.15.17514
25214.87.15.176/2814.87.15.177 to 14.87.15.19014.87.15.19114
25314.87.15.192/2814.87.15.193 to 14.87.15.20614.87.15.20714
25414.87.15.208/2814.87.15.209 to 14.87.15.22214.87.15.22314
25514.87.15.224/2814.87.15.225 to 14.87.15.23814.87.15.23914
25614.87.15.240/2814.87.15.241 to 14.87.15.25414.87.15.25514

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.