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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.

Network34.0.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
34.0.0.0
Broadcast address
34.63.255.255
First usable
34.0.0.1
Last usable
34.63.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
A (default /8)
As numbers
Hex 22000000 · Integer 570425344 to 574619647
Reverse DNS zones
0.34.in-addr.arpa
1.34.in-addr.arpa
2.34.in-addr.arpa
3.34.in-addr.arpa
4.34.in-addr.arpa
5.34.in-addr.arpa
6.34.in-addr.arpa
7.34.in-addr.arpa
8.34.in-addr.arpa
9.34.in-addr.arpa
10.34.in-addr.arpa
11.34.in-addr.arpa
12.34.in-addr.arpa
13.34.in-addr.arpa
14.34.in-addr.arpa
15.34.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00100010.00000000.00000000.0000000034.0.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00100010.00000000.00000000.0000000034.0.0.0
Broadcast00100010.00111111.11111111.1111111134.63.255.255
Split into smaller subnets/22
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

34.0.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
134.0.0.0/2234.0.0.1 to 34.0.3.25434.0.3.2551,022
234.0.4.0/2234.0.4.1 to 34.0.7.25434.0.7.2551,022
334.0.8.0/2234.0.8.1 to 34.0.11.25434.0.11.2551,022
434.0.12.0/2234.0.12.1 to 34.0.15.25434.0.15.2551,022
534.0.16.0/2234.0.16.1 to 34.0.19.25434.0.19.2551,022
634.0.20.0/2234.0.20.1 to 34.0.23.25434.0.23.2551,022
734.0.24.0/2234.0.24.1 to 34.0.27.25434.0.27.2551,022
834.0.28.0/2234.0.28.1 to 34.0.31.25434.0.31.2551,022
934.0.32.0/2234.0.32.1 to 34.0.35.25434.0.35.2551,022
1034.0.36.0/2234.0.36.1 to 34.0.39.25434.0.39.2551,022
1134.0.40.0/2234.0.40.1 to 34.0.43.25434.0.43.2551,022
1234.0.44.0/2234.0.44.1 to 34.0.47.25434.0.47.2551,022
1334.0.48.0/2234.0.48.1 to 34.0.51.25434.0.51.2551,022
1434.0.52.0/2234.0.52.1 to 34.0.55.25434.0.55.2551,022
1534.0.56.0/2234.0.56.1 to 34.0.59.25434.0.59.2551,022
1634.0.60.0/2234.0.60.1 to 34.0.63.25434.0.63.2551,022
1734.0.64.0/2234.0.64.1 to 34.0.67.25434.0.67.2551,022
1834.0.68.0/2234.0.68.1 to 34.0.71.25434.0.71.2551,022
1934.0.72.0/2234.0.72.1 to 34.0.75.25434.0.75.2551,022
2034.0.76.0/2234.0.76.1 to 34.0.79.25434.0.79.2551,022
2134.0.80.0/2234.0.80.1 to 34.0.83.25434.0.83.2551,022
2234.0.84.0/2234.0.84.1 to 34.0.87.25434.0.87.2551,022
2334.0.88.0/2234.0.88.1 to 34.0.91.25434.0.91.2551,022
2434.0.92.0/2234.0.92.1 to 34.0.95.25434.0.95.2551,022
2534.0.96.0/2234.0.96.1 to 34.0.99.25434.0.99.2551,022
2634.0.100.0/2234.0.100.1 to 34.0.103.25434.0.103.2551,022
2734.0.104.0/2234.0.104.1 to 34.0.107.25434.0.107.2551,022
2834.0.108.0/2234.0.108.1 to 34.0.111.25434.0.111.2551,022
2934.0.112.0/2234.0.112.1 to 34.0.115.25434.0.115.2551,022
3034.0.116.0/2234.0.116.1 to 34.0.119.25434.0.119.2551,022
3134.0.120.0/2234.0.120.1 to 34.0.123.25434.0.123.2551,022
3234.0.124.0/2234.0.124.1 to 34.0.127.25434.0.127.2551,022
3334.0.128.0/2234.0.128.1 to 34.0.131.25434.0.131.2551,022
3434.0.132.0/2234.0.132.1 to 34.0.135.25434.0.135.2551,022
3534.0.136.0/2234.0.136.1 to 34.0.139.25434.0.139.2551,022
3634.0.140.0/2234.0.140.1 to 34.0.143.25434.0.143.2551,022
3734.0.144.0/2234.0.144.1 to 34.0.147.25434.0.147.2551,022
3834.0.148.0/2234.0.148.1 to 34.0.151.25434.0.151.2551,022
3934.0.152.0/2234.0.152.1 to 34.0.155.25434.0.155.2551,022
4034.0.156.0/2234.0.156.1 to 34.0.159.25434.0.159.2551,022
4134.0.160.0/2234.0.160.1 to 34.0.163.25434.0.163.2551,022
4234.0.164.0/2234.0.164.1 to 34.0.167.25434.0.167.2551,022
4334.0.168.0/2234.0.168.1 to 34.0.171.25434.0.171.2551,022
4434.0.172.0/2234.0.172.1 to 34.0.175.25434.0.175.2551,022
4534.0.176.0/2234.0.176.1 to 34.0.179.25434.0.179.2551,022
4634.0.180.0/2234.0.180.1 to 34.0.183.25434.0.183.2551,022
4734.0.184.0/2234.0.184.1 to 34.0.187.25434.0.187.2551,022
4834.0.188.0/2234.0.188.1 to 34.0.191.25434.0.191.2551,022
4934.0.192.0/2234.0.192.1 to 34.0.195.25434.0.195.2551,022
5034.0.196.0/2234.0.196.1 to 34.0.199.25434.0.199.2551,022
5134.0.200.0/2234.0.200.1 to 34.0.203.25434.0.203.2551,022
5234.0.204.0/2234.0.204.1 to 34.0.207.25434.0.207.2551,022
5334.0.208.0/2234.0.208.1 to 34.0.211.25434.0.211.2551,022
5434.0.212.0/2234.0.212.1 to 34.0.215.25434.0.215.2551,022
5534.0.216.0/2234.0.216.1 to 34.0.219.25434.0.219.2551,022
5634.0.220.0/2234.0.220.1 to 34.0.223.25434.0.223.2551,022
5734.0.224.0/2234.0.224.1 to 34.0.227.25434.0.227.2551,022
5834.0.228.0/2234.0.228.1 to 34.0.231.25434.0.231.2551,022
5934.0.232.0/2234.0.232.1 to 34.0.235.25434.0.235.2551,022
6034.0.236.0/2234.0.236.1 to 34.0.239.25434.0.239.2551,022
6134.0.240.0/2234.0.240.1 to 34.0.243.25434.0.243.2551,022
6234.0.244.0/2234.0.244.1 to 34.0.247.25434.0.247.2551,022
6334.0.248.0/2234.0.248.1 to 34.0.251.25434.0.251.2551,022
6434.0.252.0/2234.0.252.1 to 34.0.255.25434.0.255.2551,022
6534.1.0.0/2234.1.0.1 to 34.1.3.25434.1.3.2551,022
6634.1.4.0/2234.1.4.1 to 34.1.7.25434.1.7.2551,022
6734.1.8.0/2234.1.8.1 to 34.1.11.25434.1.11.2551,022
6834.1.12.0/2234.1.12.1 to 34.1.15.25434.1.15.2551,022
6934.1.16.0/2234.1.16.1 to 34.1.19.25434.1.19.2551,022
7034.1.20.0/2234.1.20.1 to 34.1.23.25434.1.23.2551,022
7134.1.24.0/2234.1.24.1 to 34.1.27.25434.1.27.2551,022
7234.1.28.0/2234.1.28.1 to 34.1.31.25434.1.31.2551,022
7334.1.32.0/2234.1.32.1 to 34.1.35.25434.1.35.2551,022
7434.1.36.0/2234.1.36.1 to 34.1.39.25434.1.39.2551,022
7534.1.40.0/2234.1.40.1 to 34.1.43.25434.1.43.2551,022
7634.1.44.0/2234.1.44.1 to 34.1.47.25434.1.47.2551,022
7734.1.48.0/2234.1.48.1 to 34.1.51.25434.1.51.2551,022
7834.1.52.0/2234.1.52.1 to 34.1.55.25434.1.55.2551,022
7934.1.56.0/2234.1.56.1 to 34.1.59.25434.1.59.2551,022
8034.1.60.0/2234.1.60.1 to 34.1.63.25434.1.63.2551,022
8134.1.64.0/2234.1.64.1 to 34.1.67.25434.1.67.2551,022
8234.1.68.0/2234.1.68.1 to 34.1.71.25434.1.71.2551,022
8334.1.72.0/2234.1.72.1 to 34.1.75.25434.1.75.2551,022
8434.1.76.0/2234.1.76.1 to 34.1.79.25434.1.79.2551,022
8534.1.80.0/2234.1.80.1 to 34.1.83.25434.1.83.2551,022
8634.1.84.0/2234.1.84.1 to 34.1.87.25434.1.87.2551,022
8734.1.88.0/2234.1.88.1 to 34.1.91.25434.1.91.2551,022
8834.1.92.0/2234.1.92.1 to 34.1.95.25434.1.95.2551,022
8934.1.96.0/2234.1.96.1 to 34.1.99.25434.1.99.2551,022
9034.1.100.0/2234.1.100.1 to 34.1.103.25434.1.103.2551,022
9134.1.104.0/2234.1.104.1 to 34.1.107.25434.1.107.2551,022
9234.1.108.0/2234.1.108.1 to 34.1.111.25434.1.111.2551,022
9334.1.112.0/2234.1.112.1 to 34.1.115.25434.1.115.2551,022
9434.1.116.0/2234.1.116.1 to 34.1.119.25434.1.119.2551,022
9534.1.120.0/2234.1.120.1 to 34.1.123.25434.1.123.2551,022
9634.1.124.0/2234.1.124.1 to 34.1.127.25434.1.127.2551,022
9734.1.128.0/2234.1.128.1 to 34.1.131.25434.1.131.2551,022
9834.1.132.0/2234.1.132.1 to 34.1.135.25434.1.135.2551,022
9934.1.136.0/2234.1.136.1 to 34.1.139.25434.1.139.2551,022
10034.1.140.0/2234.1.140.1 to 34.1.143.25434.1.143.2551,022
10134.1.144.0/2234.1.144.1 to 34.1.147.25434.1.147.2551,022
10234.1.148.0/2234.1.148.1 to 34.1.151.25434.1.151.2551,022
10334.1.152.0/2234.1.152.1 to 34.1.155.25434.1.155.2551,022
10434.1.156.0/2234.1.156.1 to 34.1.159.25434.1.159.2551,022
10534.1.160.0/2234.1.160.1 to 34.1.163.25434.1.163.2551,022
10634.1.164.0/2234.1.164.1 to 34.1.167.25434.1.167.2551,022
10734.1.168.0/2234.1.168.1 to 34.1.171.25434.1.171.2551,022
10834.1.172.0/2234.1.172.1 to 34.1.175.25434.1.175.2551,022
10934.1.176.0/2234.1.176.1 to 34.1.179.25434.1.179.2551,022
11034.1.180.0/2234.1.180.1 to 34.1.183.25434.1.183.2551,022
11134.1.184.0/2234.1.184.1 to 34.1.187.25434.1.187.2551,022
11234.1.188.0/2234.1.188.1 to 34.1.191.25434.1.191.2551,022
11334.1.192.0/2234.1.192.1 to 34.1.195.25434.1.195.2551,022
11434.1.196.0/2234.1.196.1 to 34.1.199.25434.1.199.2551,022
11534.1.200.0/2234.1.200.1 to 34.1.203.25434.1.203.2551,022
11634.1.204.0/2234.1.204.1 to 34.1.207.25434.1.207.2551,022
11734.1.208.0/2234.1.208.1 to 34.1.211.25434.1.211.2551,022
11834.1.212.0/2234.1.212.1 to 34.1.215.25434.1.215.2551,022
11934.1.216.0/2234.1.216.1 to 34.1.219.25434.1.219.2551,022
12034.1.220.0/2234.1.220.1 to 34.1.223.25434.1.223.2551,022
12134.1.224.0/2234.1.224.1 to 34.1.227.25434.1.227.2551,022
12234.1.228.0/2234.1.228.1 to 34.1.231.25434.1.231.2551,022
12334.1.232.0/2234.1.232.1 to 34.1.235.25434.1.235.2551,022
12434.1.236.0/2234.1.236.1 to 34.1.239.25434.1.239.2551,022
12534.1.240.0/2234.1.240.1 to 34.1.243.25434.1.243.2551,022
12634.1.244.0/2234.1.244.1 to 34.1.247.25434.1.247.2551,022
12734.1.248.0/2234.1.248.1 to 34.1.251.25434.1.251.2551,022
12834.1.252.0/2234.1.252.1 to 34.1.255.25434.1.255.2551,022
12934.2.0.0/2234.2.0.1 to 34.2.3.25434.2.3.2551,022
13034.2.4.0/2234.2.4.1 to 34.2.7.25434.2.7.2551,022
13134.2.8.0/2234.2.8.1 to 34.2.11.25434.2.11.2551,022
13234.2.12.0/2234.2.12.1 to 34.2.15.25434.2.15.2551,022
13334.2.16.0/2234.2.16.1 to 34.2.19.25434.2.19.2551,022
13434.2.20.0/2234.2.20.1 to 34.2.23.25434.2.23.2551,022
13534.2.24.0/2234.2.24.1 to 34.2.27.25434.2.27.2551,022
13634.2.28.0/2234.2.28.1 to 34.2.31.25434.2.31.2551,022
13734.2.32.0/2234.2.32.1 to 34.2.35.25434.2.35.2551,022
13834.2.36.0/2234.2.36.1 to 34.2.39.25434.2.39.2551,022
13934.2.40.0/2234.2.40.1 to 34.2.43.25434.2.43.2551,022
14034.2.44.0/2234.2.44.1 to 34.2.47.25434.2.47.2551,022
14134.2.48.0/2234.2.48.1 to 34.2.51.25434.2.51.2551,022
14234.2.52.0/2234.2.52.1 to 34.2.55.25434.2.55.2551,022
14334.2.56.0/2234.2.56.1 to 34.2.59.25434.2.59.2551,022
14434.2.60.0/2234.2.60.1 to 34.2.63.25434.2.63.2551,022
14534.2.64.0/2234.2.64.1 to 34.2.67.25434.2.67.2551,022
14634.2.68.0/2234.2.68.1 to 34.2.71.25434.2.71.2551,022
14734.2.72.0/2234.2.72.1 to 34.2.75.25434.2.75.2551,022
14834.2.76.0/2234.2.76.1 to 34.2.79.25434.2.79.2551,022
14934.2.80.0/2234.2.80.1 to 34.2.83.25434.2.83.2551,022
15034.2.84.0/2234.2.84.1 to 34.2.87.25434.2.87.2551,022
15134.2.88.0/2234.2.88.1 to 34.2.91.25434.2.91.2551,022
15234.2.92.0/2234.2.92.1 to 34.2.95.25434.2.95.2551,022
15334.2.96.0/2234.2.96.1 to 34.2.99.25434.2.99.2551,022
15434.2.100.0/2234.2.100.1 to 34.2.103.25434.2.103.2551,022
15534.2.104.0/2234.2.104.1 to 34.2.107.25434.2.107.2551,022
15634.2.108.0/2234.2.108.1 to 34.2.111.25434.2.111.2551,022
15734.2.112.0/2234.2.112.1 to 34.2.115.25434.2.115.2551,022
15834.2.116.0/2234.2.116.1 to 34.2.119.25434.2.119.2551,022
15934.2.120.0/2234.2.120.1 to 34.2.123.25434.2.123.2551,022
16034.2.124.0/2234.2.124.1 to 34.2.127.25434.2.127.2551,022
16134.2.128.0/2234.2.128.1 to 34.2.131.25434.2.131.2551,022
16234.2.132.0/2234.2.132.1 to 34.2.135.25434.2.135.2551,022
16334.2.136.0/2234.2.136.1 to 34.2.139.25434.2.139.2551,022
16434.2.140.0/2234.2.140.1 to 34.2.143.25434.2.143.2551,022
16534.2.144.0/2234.2.144.1 to 34.2.147.25434.2.147.2551,022
16634.2.148.0/2234.2.148.1 to 34.2.151.25434.2.151.2551,022
16734.2.152.0/2234.2.152.1 to 34.2.155.25434.2.155.2551,022
16834.2.156.0/2234.2.156.1 to 34.2.159.25434.2.159.2551,022
16934.2.160.0/2234.2.160.1 to 34.2.163.25434.2.163.2551,022
17034.2.164.0/2234.2.164.1 to 34.2.167.25434.2.167.2551,022
17134.2.168.0/2234.2.168.1 to 34.2.171.25434.2.171.2551,022
17234.2.172.0/2234.2.172.1 to 34.2.175.25434.2.175.2551,022
17334.2.176.0/2234.2.176.1 to 34.2.179.25434.2.179.2551,022
17434.2.180.0/2234.2.180.1 to 34.2.183.25434.2.183.2551,022
17534.2.184.0/2234.2.184.1 to 34.2.187.25434.2.187.2551,022
17634.2.188.0/2234.2.188.1 to 34.2.191.25434.2.191.2551,022
17734.2.192.0/2234.2.192.1 to 34.2.195.25434.2.195.2551,022
17834.2.196.0/2234.2.196.1 to 34.2.199.25434.2.199.2551,022
17934.2.200.0/2234.2.200.1 to 34.2.203.25434.2.203.2551,022
18034.2.204.0/2234.2.204.1 to 34.2.207.25434.2.207.2551,022
18134.2.208.0/2234.2.208.1 to 34.2.211.25434.2.211.2551,022
18234.2.212.0/2234.2.212.1 to 34.2.215.25434.2.215.2551,022
18334.2.216.0/2234.2.216.1 to 34.2.219.25434.2.219.2551,022
18434.2.220.0/2234.2.220.1 to 34.2.223.25434.2.223.2551,022
18534.2.224.0/2234.2.224.1 to 34.2.227.25434.2.227.2551,022
18634.2.228.0/2234.2.228.1 to 34.2.231.25434.2.231.2551,022
18734.2.232.0/2234.2.232.1 to 34.2.235.25434.2.235.2551,022
18834.2.236.0/2234.2.236.1 to 34.2.239.25434.2.239.2551,022
18934.2.240.0/2234.2.240.1 to 34.2.243.25434.2.243.2551,022
19034.2.244.0/2234.2.244.1 to 34.2.247.25434.2.247.2551,022
19134.2.248.0/2234.2.248.1 to 34.2.251.25434.2.251.2551,022
19234.2.252.0/2234.2.252.1 to 34.2.255.25434.2.255.2551,022
19334.3.0.0/2234.3.0.1 to 34.3.3.25434.3.3.2551,022
19434.3.4.0/2234.3.4.1 to 34.3.7.25434.3.7.2551,022
19534.3.8.0/2234.3.8.1 to 34.3.11.25434.3.11.2551,022
19634.3.12.0/2234.3.12.1 to 34.3.15.25434.3.15.2551,022
19734.3.16.0/2234.3.16.1 to 34.3.19.25434.3.19.2551,022
19834.3.20.0/2234.3.20.1 to 34.3.23.25434.3.23.2551,022
19934.3.24.0/2234.3.24.1 to 34.3.27.25434.3.27.2551,022
20034.3.28.0/2234.3.28.1 to 34.3.31.25434.3.31.2551,022
20134.3.32.0/2234.3.32.1 to 34.3.35.25434.3.35.2551,022
20234.3.36.0/2234.3.36.1 to 34.3.39.25434.3.39.2551,022
20334.3.40.0/2234.3.40.1 to 34.3.43.25434.3.43.2551,022
20434.3.44.0/2234.3.44.1 to 34.3.47.25434.3.47.2551,022
20534.3.48.0/2234.3.48.1 to 34.3.51.25434.3.51.2551,022
20634.3.52.0/2234.3.52.1 to 34.3.55.25434.3.55.2551,022
20734.3.56.0/2234.3.56.1 to 34.3.59.25434.3.59.2551,022
20834.3.60.0/2234.3.60.1 to 34.3.63.25434.3.63.2551,022
20934.3.64.0/2234.3.64.1 to 34.3.67.25434.3.67.2551,022
21034.3.68.0/2234.3.68.1 to 34.3.71.25434.3.71.2551,022
21134.3.72.0/2234.3.72.1 to 34.3.75.25434.3.75.2551,022
21234.3.76.0/2234.3.76.1 to 34.3.79.25434.3.79.2551,022
21334.3.80.0/2234.3.80.1 to 34.3.83.25434.3.83.2551,022
21434.3.84.0/2234.3.84.1 to 34.3.87.25434.3.87.2551,022
21534.3.88.0/2234.3.88.1 to 34.3.91.25434.3.91.2551,022
21634.3.92.0/2234.3.92.1 to 34.3.95.25434.3.95.2551,022
21734.3.96.0/2234.3.96.1 to 34.3.99.25434.3.99.2551,022
21834.3.100.0/2234.3.100.1 to 34.3.103.25434.3.103.2551,022
21934.3.104.0/2234.3.104.1 to 34.3.107.25434.3.107.2551,022
22034.3.108.0/2234.3.108.1 to 34.3.111.25434.3.111.2551,022
22134.3.112.0/2234.3.112.1 to 34.3.115.25434.3.115.2551,022
22234.3.116.0/2234.3.116.1 to 34.3.119.25434.3.119.2551,022
22334.3.120.0/2234.3.120.1 to 34.3.123.25434.3.123.2551,022
22434.3.124.0/2234.3.124.1 to 34.3.127.25434.3.127.2551,022
22534.3.128.0/2234.3.128.1 to 34.3.131.25434.3.131.2551,022
22634.3.132.0/2234.3.132.1 to 34.3.135.25434.3.135.2551,022
22734.3.136.0/2234.3.136.1 to 34.3.139.25434.3.139.2551,022
22834.3.140.0/2234.3.140.1 to 34.3.143.25434.3.143.2551,022
22934.3.144.0/2234.3.144.1 to 34.3.147.25434.3.147.2551,022
23034.3.148.0/2234.3.148.1 to 34.3.151.25434.3.151.2551,022
23134.3.152.0/2234.3.152.1 to 34.3.155.25434.3.155.2551,022
23234.3.156.0/2234.3.156.1 to 34.3.159.25434.3.159.2551,022
23334.3.160.0/2234.3.160.1 to 34.3.163.25434.3.163.2551,022
23434.3.164.0/2234.3.164.1 to 34.3.167.25434.3.167.2551,022
23534.3.168.0/2234.3.168.1 to 34.3.171.25434.3.171.2551,022
23634.3.172.0/2234.3.172.1 to 34.3.175.25434.3.175.2551,022
23734.3.176.0/2234.3.176.1 to 34.3.179.25434.3.179.2551,022
23834.3.180.0/2234.3.180.1 to 34.3.183.25434.3.183.2551,022
23934.3.184.0/2234.3.184.1 to 34.3.187.25434.3.187.2551,022
24034.3.188.0/2234.3.188.1 to 34.3.191.25434.3.191.2551,022
24134.3.192.0/2234.3.192.1 to 34.3.195.25434.3.195.2551,022
24234.3.196.0/2234.3.196.1 to 34.3.199.25434.3.199.2551,022
24334.3.200.0/2234.3.200.1 to 34.3.203.25434.3.203.2551,022
24434.3.204.0/2234.3.204.1 to 34.3.207.25434.3.207.2551,022
24534.3.208.0/2234.3.208.1 to 34.3.211.25434.3.211.2551,022
24634.3.212.0/2234.3.212.1 to 34.3.215.25434.3.215.2551,022
24734.3.216.0/2234.3.216.1 to 34.3.219.25434.3.219.2551,022
24834.3.220.0/2234.3.220.1 to 34.3.223.25434.3.223.2551,022
24934.3.224.0/2234.3.224.1 to 34.3.227.25434.3.227.2551,022
25034.3.228.0/2234.3.228.1 to 34.3.231.25434.3.231.2551,022
25134.3.232.0/2234.3.232.1 to 34.3.235.25434.3.235.2551,022
25234.3.236.0/2234.3.236.1 to 34.3.239.25434.3.239.2551,022
25334.3.240.0/2234.3.240.1 to 34.3.243.25434.3.243.2551,022
25434.3.244.0/2234.3.244.1 to 34.3.247.25434.3.247.2551,022
25534.3.248.0/2234.3.248.1 to 34.3.251.25434.3.251.2551,022
25634.3.252.0/2234.3.252.1 to 34.3.255.25434.3.255.2551,022

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.