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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.

Network62.192.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
62.192.0.0
Broadcast address
62.255.255.255
First usable
62.192.0.1
Last usable
62.255.255.254
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 3EC00000 · Integer 1052770304 to 1056964607
Reverse DNS zones
192.62.in-addr.arpa
193.62.in-addr.arpa
194.62.in-addr.arpa
195.62.in-addr.arpa
196.62.in-addr.arpa
197.62.in-addr.arpa
198.62.in-addr.arpa
199.62.in-addr.arpa
200.62.in-addr.arpa
201.62.in-addr.arpa
202.62.in-addr.arpa
203.62.in-addr.arpa
204.62.in-addr.arpa
205.62.in-addr.arpa
206.62.in-addr.arpa
207.62.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
Address00111110.11000000.00000000.0000000062.192.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00111110.11000000.00000000.0000000062.192.0.0
Broadcast00111110.11111111.11111111.1111111162.255.255.255
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)

62.192.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
162.192.0.0/2262.192.0.1 to 62.192.3.25462.192.3.2551,022
262.192.4.0/2262.192.4.1 to 62.192.7.25462.192.7.2551,022
362.192.8.0/2262.192.8.1 to 62.192.11.25462.192.11.2551,022
462.192.12.0/2262.192.12.1 to 62.192.15.25462.192.15.2551,022
562.192.16.0/2262.192.16.1 to 62.192.19.25462.192.19.2551,022
662.192.20.0/2262.192.20.1 to 62.192.23.25462.192.23.2551,022
762.192.24.0/2262.192.24.1 to 62.192.27.25462.192.27.2551,022
862.192.28.0/2262.192.28.1 to 62.192.31.25462.192.31.2551,022
962.192.32.0/2262.192.32.1 to 62.192.35.25462.192.35.2551,022
1062.192.36.0/2262.192.36.1 to 62.192.39.25462.192.39.2551,022
1162.192.40.0/2262.192.40.1 to 62.192.43.25462.192.43.2551,022
1262.192.44.0/2262.192.44.1 to 62.192.47.25462.192.47.2551,022
1362.192.48.0/2262.192.48.1 to 62.192.51.25462.192.51.2551,022
1462.192.52.0/2262.192.52.1 to 62.192.55.25462.192.55.2551,022
1562.192.56.0/2262.192.56.1 to 62.192.59.25462.192.59.2551,022
1662.192.60.0/2262.192.60.1 to 62.192.63.25462.192.63.2551,022
1762.192.64.0/2262.192.64.1 to 62.192.67.25462.192.67.2551,022
1862.192.68.0/2262.192.68.1 to 62.192.71.25462.192.71.2551,022
1962.192.72.0/2262.192.72.1 to 62.192.75.25462.192.75.2551,022
2062.192.76.0/2262.192.76.1 to 62.192.79.25462.192.79.2551,022
2162.192.80.0/2262.192.80.1 to 62.192.83.25462.192.83.2551,022
2262.192.84.0/2262.192.84.1 to 62.192.87.25462.192.87.2551,022
2362.192.88.0/2262.192.88.1 to 62.192.91.25462.192.91.2551,022
2462.192.92.0/2262.192.92.1 to 62.192.95.25462.192.95.2551,022
2562.192.96.0/2262.192.96.1 to 62.192.99.25462.192.99.2551,022
2662.192.100.0/2262.192.100.1 to 62.192.103.25462.192.103.2551,022
2762.192.104.0/2262.192.104.1 to 62.192.107.25462.192.107.2551,022
2862.192.108.0/2262.192.108.1 to 62.192.111.25462.192.111.2551,022
2962.192.112.0/2262.192.112.1 to 62.192.115.25462.192.115.2551,022
3062.192.116.0/2262.192.116.1 to 62.192.119.25462.192.119.2551,022
3162.192.120.0/2262.192.120.1 to 62.192.123.25462.192.123.2551,022
3262.192.124.0/2262.192.124.1 to 62.192.127.25462.192.127.2551,022
3362.192.128.0/2262.192.128.1 to 62.192.131.25462.192.131.2551,022
3462.192.132.0/2262.192.132.1 to 62.192.135.25462.192.135.2551,022
3562.192.136.0/2262.192.136.1 to 62.192.139.25462.192.139.2551,022
3662.192.140.0/2262.192.140.1 to 62.192.143.25462.192.143.2551,022
3762.192.144.0/2262.192.144.1 to 62.192.147.25462.192.147.2551,022
3862.192.148.0/2262.192.148.1 to 62.192.151.25462.192.151.2551,022
3962.192.152.0/2262.192.152.1 to 62.192.155.25462.192.155.2551,022
4062.192.156.0/2262.192.156.1 to 62.192.159.25462.192.159.2551,022
4162.192.160.0/2262.192.160.1 to 62.192.163.25462.192.163.2551,022
4262.192.164.0/2262.192.164.1 to 62.192.167.25462.192.167.2551,022
4362.192.168.0/2262.192.168.1 to 62.192.171.25462.192.171.2551,022
4462.192.172.0/2262.192.172.1 to 62.192.175.25462.192.175.2551,022
4562.192.176.0/2262.192.176.1 to 62.192.179.25462.192.179.2551,022
4662.192.180.0/2262.192.180.1 to 62.192.183.25462.192.183.2551,022
4762.192.184.0/2262.192.184.1 to 62.192.187.25462.192.187.2551,022
4862.192.188.0/2262.192.188.1 to 62.192.191.25462.192.191.2551,022
4962.192.192.0/2262.192.192.1 to 62.192.195.25462.192.195.2551,022
5062.192.196.0/2262.192.196.1 to 62.192.199.25462.192.199.2551,022
5162.192.200.0/2262.192.200.1 to 62.192.203.25462.192.203.2551,022
5262.192.204.0/2262.192.204.1 to 62.192.207.25462.192.207.2551,022
5362.192.208.0/2262.192.208.1 to 62.192.211.25462.192.211.2551,022
5462.192.212.0/2262.192.212.1 to 62.192.215.25462.192.215.2551,022
5562.192.216.0/2262.192.216.1 to 62.192.219.25462.192.219.2551,022
5662.192.220.0/2262.192.220.1 to 62.192.223.25462.192.223.2551,022
5762.192.224.0/2262.192.224.1 to 62.192.227.25462.192.227.2551,022
5862.192.228.0/2262.192.228.1 to 62.192.231.25462.192.231.2551,022
5962.192.232.0/2262.192.232.1 to 62.192.235.25462.192.235.2551,022
6062.192.236.0/2262.192.236.1 to 62.192.239.25462.192.239.2551,022
6162.192.240.0/2262.192.240.1 to 62.192.243.25462.192.243.2551,022
6262.192.244.0/2262.192.244.1 to 62.192.247.25462.192.247.2551,022
6362.192.248.0/2262.192.248.1 to 62.192.251.25462.192.251.2551,022
6462.192.252.0/2262.192.252.1 to 62.192.255.25462.192.255.2551,022
6562.193.0.0/2262.193.0.1 to 62.193.3.25462.193.3.2551,022
6662.193.4.0/2262.193.4.1 to 62.193.7.25462.193.7.2551,022
6762.193.8.0/2262.193.8.1 to 62.193.11.25462.193.11.2551,022
6862.193.12.0/2262.193.12.1 to 62.193.15.25462.193.15.2551,022
6962.193.16.0/2262.193.16.1 to 62.193.19.25462.193.19.2551,022
7062.193.20.0/2262.193.20.1 to 62.193.23.25462.193.23.2551,022
7162.193.24.0/2262.193.24.1 to 62.193.27.25462.193.27.2551,022
7262.193.28.0/2262.193.28.1 to 62.193.31.25462.193.31.2551,022
7362.193.32.0/2262.193.32.1 to 62.193.35.25462.193.35.2551,022
7462.193.36.0/2262.193.36.1 to 62.193.39.25462.193.39.2551,022
7562.193.40.0/2262.193.40.1 to 62.193.43.25462.193.43.2551,022
7662.193.44.0/2262.193.44.1 to 62.193.47.25462.193.47.2551,022
7762.193.48.0/2262.193.48.1 to 62.193.51.25462.193.51.2551,022
7862.193.52.0/2262.193.52.1 to 62.193.55.25462.193.55.2551,022
7962.193.56.0/2262.193.56.1 to 62.193.59.25462.193.59.2551,022
8062.193.60.0/2262.193.60.1 to 62.193.63.25462.193.63.2551,022
8162.193.64.0/2262.193.64.1 to 62.193.67.25462.193.67.2551,022
8262.193.68.0/2262.193.68.1 to 62.193.71.25462.193.71.2551,022
8362.193.72.0/2262.193.72.1 to 62.193.75.25462.193.75.2551,022
8462.193.76.0/2262.193.76.1 to 62.193.79.25462.193.79.2551,022
8562.193.80.0/2262.193.80.1 to 62.193.83.25462.193.83.2551,022
8662.193.84.0/2262.193.84.1 to 62.193.87.25462.193.87.2551,022
8762.193.88.0/2262.193.88.1 to 62.193.91.25462.193.91.2551,022
8862.193.92.0/2262.193.92.1 to 62.193.95.25462.193.95.2551,022
8962.193.96.0/2262.193.96.1 to 62.193.99.25462.193.99.2551,022
9062.193.100.0/2262.193.100.1 to 62.193.103.25462.193.103.2551,022
9162.193.104.0/2262.193.104.1 to 62.193.107.25462.193.107.2551,022
9262.193.108.0/2262.193.108.1 to 62.193.111.25462.193.111.2551,022
9362.193.112.0/2262.193.112.1 to 62.193.115.25462.193.115.2551,022
9462.193.116.0/2262.193.116.1 to 62.193.119.25462.193.119.2551,022
9562.193.120.0/2262.193.120.1 to 62.193.123.25462.193.123.2551,022
9662.193.124.0/2262.193.124.1 to 62.193.127.25462.193.127.2551,022
9762.193.128.0/2262.193.128.1 to 62.193.131.25462.193.131.2551,022
9862.193.132.0/2262.193.132.1 to 62.193.135.25462.193.135.2551,022
9962.193.136.0/2262.193.136.1 to 62.193.139.25462.193.139.2551,022
10062.193.140.0/2262.193.140.1 to 62.193.143.25462.193.143.2551,022
10162.193.144.0/2262.193.144.1 to 62.193.147.25462.193.147.2551,022
10262.193.148.0/2262.193.148.1 to 62.193.151.25462.193.151.2551,022
10362.193.152.0/2262.193.152.1 to 62.193.155.25462.193.155.2551,022
10462.193.156.0/2262.193.156.1 to 62.193.159.25462.193.159.2551,022
10562.193.160.0/2262.193.160.1 to 62.193.163.25462.193.163.2551,022
10662.193.164.0/2262.193.164.1 to 62.193.167.25462.193.167.2551,022
10762.193.168.0/2262.193.168.1 to 62.193.171.25462.193.171.2551,022
10862.193.172.0/2262.193.172.1 to 62.193.175.25462.193.175.2551,022
10962.193.176.0/2262.193.176.1 to 62.193.179.25462.193.179.2551,022
11062.193.180.0/2262.193.180.1 to 62.193.183.25462.193.183.2551,022
11162.193.184.0/2262.193.184.1 to 62.193.187.25462.193.187.2551,022
11262.193.188.0/2262.193.188.1 to 62.193.191.25462.193.191.2551,022
11362.193.192.0/2262.193.192.1 to 62.193.195.25462.193.195.2551,022
11462.193.196.0/2262.193.196.1 to 62.193.199.25462.193.199.2551,022
11562.193.200.0/2262.193.200.1 to 62.193.203.25462.193.203.2551,022
11662.193.204.0/2262.193.204.1 to 62.193.207.25462.193.207.2551,022
11762.193.208.0/2262.193.208.1 to 62.193.211.25462.193.211.2551,022
11862.193.212.0/2262.193.212.1 to 62.193.215.25462.193.215.2551,022
11962.193.216.0/2262.193.216.1 to 62.193.219.25462.193.219.2551,022
12062.193.220.0/2262.193.220.1 to 62.193.223.25462.193.223.2551,022
12162.193.224.0/2262.193.224.1 to 62.193.227.25462.193.227.2551,022
12262.193.228.0/2262.193.228.1 to 62.193.231.25462.193.231.2551,022
12362.193.232.0/2262.193.232.1 to 62.193.235.25462.193.235.2551,022
12462.193.236.0/2262.193.236.1 to 62.193.239.25462.193.239.2551,022
12562.193.240.0/2262.193.240.1 to 62.193.243.25462.193.243.2551,022
12662.193.244.0/2262.193.244.1 to 62.193.247.25462.193.247.2551,022
12762.193.248.0/2262.193.248.1 to 62.193.251.25462.193.251.2551,022
12862.193.252.0/2262.193.252.1 to 62.193.255.25462.193.255.2551,022
12962.194.0.0/2262.194.0.1 to 62.194.3.25462.194.3.2551,022
13062.194.4.0/2262.194.4.1 to 62.194.7.25462.194.7.2551,022
13162.194.8.0/2262.194.8.1 to 62.194.11.25462.194.11.2551,022
13262.194.12.0/2262.194.12.1 to 62.194.15.25462.194.15.2551,022
13362.194.16.0/2262.194.16.1 to 62.194.19.25462.194.19.2551,022
13462.194.20.0/2262.194.20.1 to 62.194.23.25462.194.23.2551,022
13562.194.24.0/2262.194.24.1 to 62.194.27.25462.194.27.2551,022
13662.194.28.0/2262.194.28.1 to 62.194.31.25462.194.31.2551,022
13762.194.32.0/2262.194.32.1 to 62.194.35.25462.194.35.2551,022
13862.194.36.0/2262.194.36.1 to 62.194.39.25462.194.39.2551,022
13962.194.40.0/2262.194.40.1 to 62.194.43.25462.194.43.2551,022
14062.194.44.0/2262.194.44.1 to 62.194.47.25462.194.47.2551,022
14162.194.48.0/2262.194.48.1 to 62.194.51.25462.194.51.2551,022
14262.194.52.0/2262.194.52.1 to 62.194.55.25462.194.55.2551,022
14362.194.56.0/2262.194.56.1 to 62.194.59.25462.194.59.2551,022
14462.194.60.0/2262.194.60.1 to 62.194.63.25462.194.63.2551,022
14562.194.64.0/2262.194.64.1 to 62.194.67.25462.194.67.2551,022
14662.194.68.0/2262.194.68.1 to 62.194.71.25462.194.71.2551,022
14762.194.72.0/2262.194.72.1 to 62.194.75.25462.194.75.2551,022
14862.194.76.0/2262.194.76.1 to 62.194.79.25462.194.79.2551,022
14962.194.80.0/2262.194.80.1 to 62.194.83.25462.194.83.2551,022
15062.194.84.0/2262.194.84.1 to 62.194.87.25462.194.87.2551,022
15162.194.88.0/2262.194.88.1 to 62.194.91.25462.194.91.2551,022
15262.194.92.0/2262.194.92.1 to 62.194.95.25462.194.95.2551,022
15362.194.96.0/2262.194.96.1 to 62.194.99.25462.194.99.2551,022
15462.194.100.0/2262.194.100.1 to 62.194.103.25462.194.103.2551,022
15562.194.104.0/2262.194.104.1 to 62.194.107.25462.194.107.2551,022
15662.194.108.0/2262.194.108.1 to 62.194.111.25462.194.111.2551,022
15762.194.112.0/2262.194.112.1 to 62.194.115.25462.194.115.2551,022
15862.194.116.0/2262.194.116.1 to 62.194.119.25462.194.119.2551,022
15962.194.120.0/2262.194.120.1 to 62.194.123.25462.194.123.2551,022
16062.194.124.0/2262.194.124.1 to 62.194.127.25462.194.127.2551,022
16162.194.128.0/2262.194.128.1 to 62.194.131.25462.194.131.2551,022
16262.194.132.0/2262.194.132.1 to 62.194.135.25462.194.135.2551,022
16362.194.136.0/2262.194.136.1 to 62.194.139.25462.194.139.2551,022
16462.194.140.0/2262.194.140.1 to 62.194.143.25462.194.143.2551,022
16562.194.144.0/2262.194.144.1 to 62.194.147.25462.194.147.2551,022
16662.194.148.0/2262.194.148.1 to 62.194.151.25462.194.151.2551,022
16762.194.152.0/2262.194.152.1 to 62.194.155.25462.194.155.2551,022
16862.194.156.0/2262.194.156.1 to 62.194.159.25462.194.159.2551,022
16962.194.160.0/2262.194.160.1 to 62.194.163.25462.194.163.2551,022
17062.194.164.0/2262.194.164.1 to 62.194.167.25462.194.167.2551,022
17162.194.168.0/2262.194.168.1 to 62.194.171.25462.194.171.2551,022
17262.194.172.0/2262.194.172.1 to 62.194.175.25462.194.175.2551,022
17362.194.176.0/2262.194.176.1 to 62.194.179.25462.194.179.2551,022
17462.194.180.0/2262.194.180.1 to 62.194.183.25462.194.183.2551,022
17562.194.184.0/2262.194.184.1 to 62.194.187.25462.194.187.2551,022
17662.194.188.0/2262.194.188.1 to 62.194.191.25462.194.191.2551,022
17762.194.192.0/2262.194.192.1 to 62.194.195.25462.194.195.2551,022
17862.194.196.0/2262.194.196.1 to 62.194.199.25462.194.199.2551,022
17962.194.200.0/2262.194.200.1 to 62.194.203.25462.194.203.2551,022
18062.194.204.0/2262.194.204.1 to 62.194.207.25462.194.207.2551,022
18162.194.208.0/2262.194.208.1 to 62.194.211.25462.194.211.2551,022
18262.194.212.0/2262.194.212.1 to 62.194.215.25462.194.215.2551,022
18362.194.216.0/2262.194.216.1 to 62.194.219.25462.194.219.2551,022
18462.194.220.0/2262.194.220.1 to 62.194.223.25462.194.223.2551,022
18562.194.224.0/2262.194.224.1 to 62.194.227.25462.194.227.2551,022
18662.194.228.0/2262.194.228.1 to 62.194.231.25462.194.231.2551,022
18762.194.232.0/2262.194.232.1 to 62.194.235.25462.194.235.2551,022
18862.194.236.0/2262.194.236.1 to 62.194.239.25462.194.239.2551,022
18962.194.240.0/2262.194.240.1 to 62.194.243.25462.194.243.2551,022
19062.194.244.0/2262.194.244.1 to 62.194.247.25462.194.247.2551,022
19162.194.248.0/2262.194.248.1 to 62.194.251.25462.194.251.2551,022
19262.194.252.0/2262.194.252.1 to 62.194.255.25462.194.255.2551,022
19362.195.0.0/2262.195.0.1 to 62.195.3.25462.195.3.2551,022
19462.195.4.0/2262.195.4.1 to 62.195.7.25462.195.7.2551,022
19562.195.8.0/2262.195.8.1 to 62.195.11.25462.195.11.2551,022
19662.195.12.0/2262.195.12.1 to 62.195.15.25462.195.15.2551,022
19762.195.16.0/2262.195.16.1 to 62.195.19.25462.195.19.2551,022
19862.195.20.0/2262.195.20.1 to 62.195.23.25462.195.23.2551,022
19962.195.24.0/2262.195.24.1 to 62.195.27.25462.195.27.2551,022
20062.195.28.0/2262.195.28.1 to 62.195.31.25462.195.31.2551,022
20162.195.32.0/2262.195.32.1 to 62.195.35.25462.195.35.2551,022
20262.195.36.0/2262.195.36.1 to 62.195.39.25462.195.39.2551,022
20362.195.40.0/2262.195.40.1 to 62.195.43.25462.195.43.2551,022
20462.195.44.0/2262.195.44.1 to 62.195.47.25462.195.47.2551,022
20562.195.48.0/2262.195.48.1 to 62.195.51.25462.195.51.2551,022
20662.195.52.0/2262.195.52.1 to 62.195.55.25462.195.55.2551,022
20762.195.56.0/2262.195.56.1 to 62.195.59.25462.195.59.2551,022
20862.195.60.0/2262.195.60.1 to 62.195.63.25462.195.63.2551,022
20962.195.64.0/2262.195.64.1 to 62.195.67.25462.195.67.2551,022
21062.195.68.0/2262.195.68.1 to 62.195.71.25462.195.71.2551,022
21162.195.72.0/2262.195.72.1 to 62.195.75.25462.195.75.2551,022
21262.195.76.0/2262.195.76.1 to 62.195.79.25462.195.79.2551,022
21362.195.80.0/2262.195.80.1 to 62.195.83.25462.195.83.2551,022
21462.195.84.0/2262.195.84.1 to 62.195.87.25462.195.87.2551,022
21562.195.88.0/2262.195.88.1 to 62.195.91.25462.195.91.2551,022
21662.195.92.0/2262.195.92.1 to 62.195.95.25462.195.95.2551,022
21762.195.96.0/2262.195.96.1 to 62.195.99.25462.195.99.2551,022
21862.195.100.0/2262.195.100.1 to 62.195.103.25462.195.103.2551,022
21962.195.104.0/2262.195.104.1 to 62.195.107.25462.195.107.2551,022
22062.195.108.0/2262.195.108.1 to 62.195.111.25462.195.111.2551,022
22162.195.112.0/2262.195.112.1 to 62.195.115.25462.195.115.2551,022
22262.195.116.0/2262.195.116.1 to 62.195.119.25462.195.119.2551,022
22362.195.120.0/2262.195.120.1 to 62.195.123.25462.195.123.2551,022
22462.195.124.0/2262.195.124.1 to 62.195.127.25462.195.127.2551,022
22562.195.128.0/2262.195.128.1 to 62.195.131.25462.195.131.2551,022
22662.195.132.0/2262.195.132.1 to 62.195.135.25462.195.135.2551,022
22762.195.136.0/2262.195.136.1 to 62.195.139.25462.195.139.2551,022
22862.195.140.0/2262.195.140.1 to 62.195.143.25462.195.143.2551,022
22962.195.144.0/2262.195.144.1 to 62.195.147.25462.195.147.2551,022
23062.195.148.0/2262.195.148.1 to 62.195.151.25462.195.151.2551,022
23162.195.152.0/2262.195.152.1 to 62.195.155.25462.195.155.2551,022
23262.195.156.0/2262.195.156.1 to 62.195.159.25462.195.159.2551,022
23362.195.160.0/2262.195.160.1 to 62.195.163.25462.195.163.2551,022
23462.195.164.0/2262.195.164.1 to 62.195.167.25462.195.167.2551,022
23562.195.168.0/2262.195.168.1 to 62.195.171.25462.195.171.2551,022
23662.195.172.0/2262.195.172.1 to 62.195.175.25462.195.175.2551,022
23762.195.176.0/2262.195.176.1 to 62.195.179.25462.195.179.2551,022
23862.195.180.0/2262.195.180.1 to 62.195.183.25462.195.183.2551,022
23962.195.184.0/2262.195.184.1 to 62.195.187.25462.195.187.2551,022
24062.195.188.0/2262.195.188.1 to 62.195.191.25462.195.191.2551,022
24162.195.192.0/2262.195.192.1 to 62.195.195.25462.195.195.2551,022
24262.195.196.0/2262.195.196.1 to 62.195.199.25462.195.199.2551,022
24362.195.200.0/2262.195.200.1 to 62.195.203.25462.195.203.2551,022
24462.195.204.0/2262.195.204.1 to 62.195.207.25462.195.207.2551,022
24562.195.208.0/2262.195.208.1 to 62.195.211.25462.195.211.2551,022
24662.195.212.0/2262.195.212.1 to 62.195.215.25462.195.215.2551,022
24762.195.216.0/2262.195.216.1 to 62.195.219.25462.195.219.2551,022
24862.195.220.0/2262.195.220.1 to 62.195.223.25462.195.223.2551,022
24962.195.224.0/2262.195.224.1 to 62.195.227.25462.195.227.2551,022
25062.195.228.0/2262.195.228.1 to 62.195.231.25462.195.231.2551,022
25162.195.232.0/2262.195.232.1 to 62.195.235.25462.195.235.2551,022
25262.195.236.0/2262.195.236.1 to 62.195.239.25462.195.239.2551,022
25362.195.240.0/2262.195.240.1 to 62.195.243.25462.195.243.2551,022
25462.195.244.0/2262.195.244.1 to 62.195.247.25462.195.247.2551,022
25562.195.248.0/2262.195.248.1 to 62.195.251.25462.195.251.2551,022
25662.195.252.0/2262.195.252.1 to 62.195.255.25462.195.255.2551,022

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.