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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.

Network52.0.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
52.0.0.0
Broadcast address
52.63.255.255
First usable
52.0.0.1
Last usable
52.63.255.254
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 34000000 · Integer 872415232 to 876609535
Reverse DNS zones
0.52.in-addr.arpa
1.52.in-addr.arpa
2.52.in-addr.arpa
3.52.in-addr.arpa
4.52.in-addr.arpa
5.52.in-addr.arpa
6.52.in-addr.arpa
7.52.in-addr.arpa
8.52.in-addr.arpa
9.52.in-addr.arpa
10.52.in-addr.arpa
11.52.in-addr.arpa
12.52.in-addr.arpa
13.52.in-addr.arpa
14.52.in-addr.arpa
15.52.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
Address00110100.00000000.00000000.0000000052.0.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00110100.00000000.00000000.0000000052.0.0.0
Broadcast00110100.00111111.11111111.1111111152.63.255.255
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)

52.0.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
152.0.0.0/2252.0.0.1 to 52.0.3.25452.0.3.2551,022
252.0.4.0/2252.0.4.1 to 52.0.7.25452.0.7.2551,022
352.0.8.0/2252.0.8.1 to 52.0.11.25452.0.11.2551,022
452.0.12.0/2252.0.12.1 to 52.0.15.25452.0.15.2551,022
552.0.16.0/2252.0.16.1 to 52.0.19.25452.0.19.2551,022
652.0.20.0/2252.0.20.1 to 52.0.23.25452.0.23.2551,022
752.0.24.0/2252.0.24.1 to 52.0.27.25452.0.27.2551,022
852.0.28.0/2252.0.28.1 to 52.0.31.25452.0.31.2551,022
952.0.32.0/2252.0.32.1 to 52.0.35.25452.0.35.2551,022
1052.0.36.0/2252.0.36.1 to 52.0.39.25452.0.39.2551,022
1152.0.40.0/2252.0.40.1 to 52.0.43.25452.0.43.2551,022
1252.0.44.0/2252.0.44.1 to 52.0.47.25452.0.47.2551,022
1352.0.48.0/2252.0.48.1 to 52.0.51.25452.0.51.2551,022
1452.0.52.0/2252.0.52.1 to 52.0.55.25452.0.55.2551,022
1552.0.56.0/2252.0.56.1 to 52.0.59.25452.0.59.2551,022
1652.0.60.0/2252.0.60.1 to 52.0.63.25452.0.63.2551,022
1752.0.64.0/2252.0.64.1 to 52.0.67.25452.0.67.2551,022
1852.0.68.0/2252.0.68.1 to 52.0.71.25452.0.71.2551,022
1952.0.72.0/2252.0.72.1 to 52.0.75.25452.0.75.2551,022
2052.0.76.0/2252.0.76.1 to 52.0.79.25452.0.79.2551,022
2152.0.80.0/2252.0.80.1 to 52.0.83.25452.0.83.2551,022
2252.0.84.0/2252.0.84.1 to 52.0.87.25452.0.87.2551,022
2352.0.88.0/2252.0.88.1 to 52.0.91.25452.0.91.2551,022
2452.0.92.0/2252.0.92.1 to 52.0.95.25452.0.95.2551,022
2552.0.96.0/2252.0.96.1 to 52.0.99.25452.0.99.2551,022
2652.0.100.0/2252.0.100.1 to 52.0.103.25452.0.103.2551,022
2752.0.104.0/2252.0.104.1 to 52.0.107.25452.0.107.2551,022
2852.0.108.0/2252.0.108.1 to 52.0.111.25452.0.111.2551,022
2952.0.112.0/2252.0.112.1 to 52.0.115.25452.0.115.2551,022
3052.0.116.0/2252.0.116.1 to 52.0.119.25452.0.119.2551,022
3152.0.120.0/2252.0.120.1 to 52.0.123.25452.0.123.2551,022
3252.0.124.0/2252.0.124.1 to 52.0.127.25452.0.127.2551,022
3352.0.128.0/2252.0.128.1 to 52.0.131.25452.0.131.2551,022
3452.0.132.0/2252.0.132.1 to 52.0.135.25452.0.135.2551,022
3552.0.136.0/2252.0.136.1 to 52.0.139.25452.0.139.2551,022
3652.0.140.0/2252.0.140.1 to 52.0.143.25452.0.143.2551,022
3752.0.144.0/2252.0.144.1 to 52.0.147.25452.0.147.2551,022
3852.0.148.0/2252.0.148.1 to 52.0.151.25452.0.151.2551,022
3952.0.152.0/2252.0.152.1 to 52.0.155.25452.0.155.2551,022
4052.0.156.0/2252.0.156.1 to 52.0.159.25452.0.159.2551,022
4152.0.160.0/2252.0.160.1 to 52.0.163.25452.0.163.2551,022
4252.0.164.0/2252.0.164.1 to 52.0.167.25452.0.167.2551,022
4352.0.168.0/2252.0.168.1 to 52.0.171.25452.0.171.2551,022
4452.0.172.0/2252.0.172.1 to 52.0.175.25452.0.175.2551,022
4552.0.176.0/2252.0.176.1 to 52.0.179.25452.0.179.2551,022
4652.0.180.0/2252.0.180.1 to 52.0.183.25452.0.183.2551,022
4752.0.184.0/2252.0.184.1 to 52.0.187.25452.0.187.2551,022
4852.0.188.0/2252.0.188.1 to 52.0.191.25452.0.191.2551,022
4952.0.192.0/2252.0.192.1 to 52.0.195.25452.0.195.2551,022
5052.0.196.0/2252.0.196.1 to 52.0.199.25452.0.199.2551,022
5152.0.200.0/2252.0.200.1 to 52.0.203.25452.0.203.2551,022
5252.0.204.0/2252.0.204.1 to 52.0.207.25452.0.207.2551,022
5352.0.208.0/2252.0.208.1 to 52.0.211.25452.0.211.2551,022
5452.0.212.0/2252.0.212.1 to 52.0.215.25452.0.215.2551,022
5552.0.216.0/2252.0.216.1 to 52.0.219.25452.0.219.2551,022
5652.0.220.0/2252.0.220.1 to 52.0.223.25452.0.223.2551,022
5752.0.224.0/2252.0.224.1 to 52.0.227.25452.0.227.2551,022
5852.0.228.0/2252.0.228.1 to 52.0.231.25452.0.231.2551,022
5952.0.232.0/2252.0.232.1 to 52.0.235.25452.0.235.2551,022
6052.0.236.0/2252.0.236.1 to 52.0.239.25452.0.239.2551,022
6152.0.240.0/2252.0.240.1 to 52.0.243.25452.0.243.2551,022
6252.0.244.0/2252.0.244.1 to 52.0.247.25452.0.247.2551,022
6352.0.248.0/2252.0.248.1 to 52.0.251.25452.0.251.2551,022
6452.0.252.0/2252.0.252.1 to 52.0.255.25452.0.255.2551,022
6552.1.0.0/2252.1.0.1 to 52.1.3.25452.1.3.2551,022
6652.1.4.0/2252.1.4.1 to 52.1.7.25452.1.7.2551,022
6752.1.8.0/2252.1.8.1 to 52.1.11.25452.1.11.2551,022
6852.1.12.0/2252.1.12.1 to 52.1.15.25452.1.15.2551,022
6952.1.16.0/2252.1.16.1 to 52.1.19.25452.1.19.2551,022
7052.1.20.0/2252.1.20.1 to 52.1.23.25452.1.23.2551,022
7152.1.24.0/2252.1.24.1 to 52.1.27.25452.1.27.2551,022
7252.1.28.0/2252.1.28.1 to 52.1.31.25452.1.31.2551,022
7352.1.32.0/2252.1.32.1 to 52.1.35.25452.1.35.2551,022
7452.1.36.0/2252.1.36.1 to 52.1.39.25452.1.39.2551,022
7552.1.40.0/2252.1.40.1 to 52.1.43.25452.1.43.2551,022
7652.1.44.0/2252.1.44.1 to 52.1.47.25452.1.47.2551,022
7752.1.48.0/2252.1.48.1 to 52.1.51.25452.1.51.2551,022
7852.1.52.0/2252.1.52.1 to 52.1.55.25452.1.55.2551,022
7952.1.56.0/2252.1.56.1 to 52.1.59.25452.1.59.2551,022
8052.1.60.0/2252.1.60.1 to 52.1.63.25452.1.63.2551,022
8152.1.64.0/2252.1.64.1 to 52.1.67.25452.1.67.2551,022
8252.1.68.0/2252.1.68.1 to 52.1.71.25452.1.71.2551,022
8352.1.72.0/2252.1.72.1 to 52.1.75.25452.1.75.2551,022
8452.1.76.0/2252.1.76.1 to 52.1.79.25452.1.79.2551,022
8552.1.80.0/2252.1.80.1 to 52.1.83.25452.1.83.2551,022
8652.1.84.0/2252.1.84.1 to 52.1.87.25452.1.87.2551,022
8752.1.88.0/2252.1.88.1 to 52.1.91.25452.1.91.2551,022
8852.1.92.0/2252.1.92.1 to 52.1.95.25452.1.95.2551,022
8952.1.96.0/2252.1.96.1 to 52.1.99.25452.1.99.2551,022
9052.1.100.0/2252.1.100.1 to 52.1.103.25452.1.103.2551,022
9152.1.104.0/2252.1.104.1 to 52.1.107.25452.1.107.2551,022
9252.1.108.0/2252.1.108.1 to 52.1.111.25452.1.111.2551,022
9352.1.112.0/2252.1.112.1 to 52.1.115.25452.1.115.2551,022
9452.1.116.0/2252.1.116.1 to 52.1.119.25452.1.119.2551,022
9552.1.120.0/2252.1.120.1 to 52.1.123.25452.1.123.2551,022
9652.1.124.0/2252.1.124.1 to 52.1.127.25452.1.127.2551,022
9752.1.128.0/2252.1.128.1 to 52.1.131.25452.1.131.2551,022
9852.1.132.0/2252.1.132.1 to 52.1.135.25452.1.135.2551,022
9952.1.136.0/2252.1.136.1 to 52.1.139.25452.1.139.2551,022
10052.1.140.0/2252.1.140.1 to 52.1.143.25452.1.143.2551,022
10152.1.144.0/2252.1.144.1 to 52.1.147.25452.1.147.2551,022
10252.1.148.0/2252.1.148.1 to 52.1.151.25452.1.151.2551,022
10352.1.152.0/2252.1.152.1 to 52.1.155.25452.1.155.2551,022
10452.1.156.0/2252.1.156.1 to 52.1.159.25452.1.159.2551,022
10552.1.160.0/2252.1.160.1 to 52.1.163.25452.1.163.2551,022
10652.1.164.0/2252.1.164.1 to 52.1.167.25452.1.167.2551,022
10752.1.168.0/2252.1.168.1 to 52.1.171.25452.1.171.2551,022
10852.1.172.0/2252.1.172.1 to 52.1.175.25452.1.175.2551,022
10952.1.176.0/2252.1.176.1 to 52.1.179.25452.1.179.2551,022
11052.1.180.0/2252.1.180.1 to 52.1.183.25452.1.183.2551,022
11152.1.184.0/2252.1.184.1 to 52.1.187.25452.1.187.2551,022
11252.1.188.0/2252.1.188.1 to 52.1.191.25452.1.191.2551,022
11352.1.192.0/2252.1.192.1 to 52.1.195.25452.1.195.2551,022
11452.1.196.0/2252.1.196.1 to 52.1.199.25452.1.199.2551,022
11552.1.200.0/2252.1.200.1 to 52.1.203.25452.1.203.2551,022
11652.1.204.0/2252.1.204.1 to 52.1.207.25452.1.207.2551,022
11752.1.208.0/2252.1.208.1 to 52.1.211.25452.1.211.2551,022
11852.1.212.0/2252.1.212.1 to 52.1.215.25452.1.215.2551,022
11952.1.216.0/2252.1.216.1 to 52.1.219.25452.1.219.2551,022
12052.1.220.0/2252.1.220.1 to 52.1.223.25452.1.223.2551,022
12152.1.224.0/2252.1.224.1 to 52.1.227.25452.1.227.2551,022
12252.1.228.0/2252.1.228.1 to 52.1.231.25452.1.231.2551,022
12352.1.232.0/2252.1.232.1 to 52.1.235.25452.1.235.2551,022
12452.1.236.0/2252.1.236.1 to 52.1.239.25452.1.239.2551,022
12552.1.240.0/2252.1.240.1 to 52.1.243.25452.1.243.2551,022
12652.1.244.0/2252.1.244.1 to 52.1.247.25452.1.247.2551,022
12752.1.248.0/2252.1.248.1 to 52.1.251.25452.1.251.2551,022
12852.1.252.0/2252.1.252.1 to 52.1.255.25452.1.255.2551,022
12952.2.0.0/2252.2.0.1 to 52.2.3.25452.2.3.2551,022
13052.2.4.0/2252.2.4.1 to 52.2.7.25452.2.7.2551,022
13152.2.8.0/2252.2.8.1 to 52.2.11.25452.2.11.2551,022
13252.2.12.0/2252.2.12.1 to 52.2.15.25452.2.15.2551,022
13352.2.16.0/2252.2.16.1 to 52.2.19.25452.2.19.2551,022
13452.2.20.0/2252.2.20.1 to 52.2.23.25452.2.23.2551,022
13552.2.24.0/2252.2.24.1 to 52.2.27.25452.2.27.2551,022
13652.2.28.0/2252.2.28.1 to 52.2.31.25452.2.31.2551,022
13752.2.32.0/2252.2.32.1 to 52.2.35.25452.2.35.2551,022
13852.2.36.0/2252.2.36.1 to 52.2.39.25452.2.39.2551,022
13952.2.40.0/2252.2.40.1 to 52.2.43.25452.2.43.2551,022
14052.2.44.0/2252.2.44.1 to 52.2.47.25452.2.47.2551,022
14152.2.48.0/2252.2.48.1 to 52.2.51.25452.2.51.2551,022
14252.2.52.0/2252.2.52.1 to 52.2.55.25452.2.55.2551,022
14352.2.56.0/2252.2.56.1 to 52.2.59.25452.2.59.2551,022
14452.2.60.0/2252.2.60.1 to 52.2.63.25452.2.63.2551,022
14552.2.64.0/2252.2.64.1 to 52.2.67.25452.2.67.2551,022
14652.2.68.0/2252.2.68.1 to 52.2.71.25452.2.71.2551,022
14752.2.72.0/2252.2.72.1 to 52.2.75.25452.2.75.2551,022
14852.2.76.0/2252.2.76.1 to 52.2.79.25452.2.79.2551,022
14952.2.80.0/2252.2.80.1 to 52.2.83.25452.2.83.2551,022
15052.2.84.0/2252.2.84.1 to 52.2.87.25452.2.87.2551,022
15152.2.88.0/2252.2.88.1 to 52.2.91.25452.2.91.2551,022
15252.2.92.0/2252.2.92.1 to 52.2.95.25452.2.95.2551,022
15352.2.96.0/2252.2.96.1 to 52.2.99.25452.2.99.2551,022
15452.2.100.0/2252.2.100.1 to 52.2.103.25452.2.103.2551,022
15552.2.104.0/2252.2.104.1 to 52.2.107.25452.2.107.2551,022
15652.2.108.0/2252.2.108.1 to 52.2.111.25452.2.111.2551,022
15752.2.112.0/2252.2.112.1 to 52.2.115.25452.2.115.2551,022
15852.2.116.0/2252.2.116.1 to 52.2.119.25452.2.119.2551,022
15952.2.120.0/2252.2.120.1 to 52.2.123.25452.2.123.2551,022
16052.2.124.0/2252.2.124.1 to 52.2.127.25452.2.127.2551,022
16152.2.128.0/2252.2.128.1 to 52.2.131.25452.2.131.2551,022
16252.2.132.0/2252.2.132.1 to 52.2.135.25452.2.135.2551,022
16352.2.136.0/2252.2.136.1 to 52.2.139.25452.2.139.2551,022
16452.2.140.0/2252.2.140.1 to 52.2.143.25452.2.143.2551,022
16552.2.144.0/2252.2.144.1 to 52.2.147.25452.2.147.2551,022
16652.2.148.0/2252.2.148.1 to 52.2.151.25452.2.151.2551,022
16752.2.152.0/2252.2.152.1 to 52.2.155.25452.2.155.2551,022
16852.2.156.0/2252.2.156.1 to 52.2.159.25452.2.159.2551,022
16952.2.160.0/2252.2.160.1 to 52.2.163.25452.2.163.2551,022
17052.2.164.0/2252.2.164.1 to 52.2.167.25452.2.167.2551,022
17152.2.168.0/2252.2.168.1 to 52.2.171.25452.2.171.2551,022
17252.2.172.0/2252.2.172.1 to 52.2.175.25452.2.175.2551,022
17352.2.176.0/2252.2.176.1 to 52.2.179.25452.2.179.2551,022
17452.2.180.0/2252.2.180.1 to 52.2.183.25452.2.183.2551,022
17552.2.184.0/2252.2.184.1 to 52.2.187.25452.2.187.2551,022
17652.2.188.0/2252.2.188.1 to 52.2.191.25452.2.191.2551,022
17752.2.192.0/2252.2.192.1 to 52.2.195.25452.2.195.2551,022
17852.2.196.0/2252.2.196.1 to 52.2.199.25452.2.199.2551,022
17952.2.200.0/2252.2.200.1 to 52.2.203.25452.2.203.2551,022
18052.2.204.0/2252.2.204.1 to 52.2.207.25452.2.207.2551,022
18152.2.208.0/2252.2.208.1 to 52.2.211.25452.2.211.2551,022
18252.2.212.0/2252.2.212.1 to 52.2.215.25452.2.215.2551,022
18352.2.216.0/2252.2.216.1 to 52.2.219.25452.2.219.2551,022
18452.2.220.0/2252.2.220.1 to 52.2.223.25452.2.223.2551,022
18552.2.224.0/2252.2.224.1 to 52.2.227.25452.2.227.2551,022
18652.2.228.0/2252.2.228.1 to 52.2.231.25452.2.231.2551,022
18752.2.232.0/2252.2.232.1 to 52.2.235.25452.2.235.2551,022
18852.2.236.0/2252.2.236.1 to 52.2.239.25452.2.239.2551,022
18952.2.240.0/2252.2.240.1 to 52.2.243.25452.2.243.2551,022
19052.2.244.0/2252.2.244.1 to 52.2.247.25452.2.247.2551,022
19152.2.248.0/2252.2.248.1 to 52.2.251.25452.2.251.2551,022
19252.2.252.0/2252.2.252.1 to 52.2.255.25452.2.255.2551,022
19352.3.0.0/2252.3.0.1 to 52.3.3.25452.3.3.2551,022
19452.3.4.0/2252.3.4.1 to 52.3.7.25452.3.7.2551,022
19552.3.8.0/2252.3.8.1 to 52.3.11.25452.3.11.2551,022
19652.3.12.0/2252.3.12.1 to 52.3.15.25452.3.15.2551,022
19752.3.16.0/2252.3.16.1 to 52.3.19.25452.3.19.2551,022
19852.3.20.0/2252.3.20.1 to 52.3.23.25452.3.23.2551,022
19952.3.24.0/2252.3.24.1 to 52.3.27.25452.3.27.2551,022
20052.3.28.0/2252.3.28.1 to 52.3.31.25452.3.31.2551,022
20152.3.32.0/2252.3.32.1 to 52.3.35.25452.3.35.2551,022
20252.3.36.0/2252.3.36.1 to 52.3.39.25452.3.39.2551,022
20352.3.40.0/2252.3.40.1 to 52.3.43.25452.3.43.2551,022
20452.3.44.0/2252.3.44.1 to 52.3.47.25452.3.47.2551,022
20552.3.48.0/2252.3.48.1 to 52.3.51.25452.3.51.2551,022
20652.3.52.0/2252.3.52.1 to 52.3.55.25452.3.55.2551,022
20752.3.56.0/2252.3.56.1 to 52.3.59.25452.3.59.2551,022
20852.3.60.0/2252.3.60.1 to 52.3.63.25452.3.63.2551,022
20952.3.64.0/2252.3.64.1 to 52.3.67.25452.3.67.2551,022
21052.3.68.0/2252.3.68.1 to 52.3.71.25452.3.71.2551,022
21152.3.72.0/2252.3.72.1 to 52.3.75.25452.3.75.2551,022
21252.3.76.0/2252.3.76.1 to 52.3.79.25452.3.79.2551,022
21352.3.80.0/2252.3.80.1 to 52.3.83.25452.3.83.2551,022
21452.3.84.0/2252.3.84.1 to 52.3.87.25452.3.87.2551,022
21552.3.88.0/2252.3.88.1 to 52.3.91.25452.3.91.2551,022
21652.3.92.0/2252.3.92.1 to 52.3.95.25452.3.95.2551,022
21752.3.96.0/2252.3.96.1 to 52.3.99.25452.3.99.2551,022
21852.3.100.0/2252.3.100.1 to 52.3.103.25452.3.103.2551,022
21952.3.104.0/2252.3.104.1 to 52.3.107.25452.3.107.2551,022
22052.3.108.0/2252.3.108.1 to 52.3.111.25452.3.111.2551,022
22152.3.112.0/2252.3.112.1 to 52.3.115.25452.3.115.2551,022
22252.3.116.0/2252.3.116.1 to 52.3.119.25452.3.119.2551,022
22352.3.120.0/2252.3.120.1 to 52.3.123.25452.3.123.2551,022
22452.3.124.0/2252.3.124.1 to 52.3.127.25452.3.127.2551,022
22552.3.128.0/2252.3.128.1 to 52.3.131.25452.3.131.2551,022
22652.3.132.0/2252.3.132.1 to 52.3.135.25452.3.135.2551,022
22752.3.136.0/2252.3.136.1 to 52.3.139.25452.3.139.2551,022
22852.3.140.0/2252.3.140.1 to 52.3.143.25452.3.143.2551,022
22952.3.144.0/2252.3.144.1 to 52.3.147.25452.3.147.2551,022
23052.3.148.0/2252.3.148.1 to 52.3.151.25452.3.151.2551,022
23152.3.152.0/2252.3.152.1 to 52.3.155.25452.3.155.2551,022
23252.3.156.0/2252.3.156.1 to 52.3.159.25452.3.159.2551,022
23352.3.160.0/2252.3.160.1 to 52.3.163.25452.3.163.2551,022
23452.3.164.0/2252.3.164.1 to 52.3.167.25452.3.167.2551,022
23552.3.168.0/2252.3.168.1 to 52.3.171.25452.3.171.2551,022
23652.3.172.0/2252.3.172.1 to 52.3.175.25452.3.175.2551,022
23752.3.176.0/2252.3.176.1 to 52.3.179.25452.3.179.2551,022
23852.3.180.0/2252.3.180.1 to 52.3.183.25452.3.183.2551,022
23952.3.184.0/2252.3.184.1 to 52.3.187.25452.3.187.2551,022
24052.3.188.0/2252.3.188.1 to 52.3.191.25452.3.191.2551,022
24152.3.192.0/2252.3.192.1 to 52.3.195.25452.3.195.2551,022
24252.3.196.0/2252.3.196.1 to 52.3.199.25452.3.199.2551,022
24352.3.200.0/2252.3.200.1 to 52.3.203.25452.3.203.2551,022
24452.3.204.0/2252.3.204.1 to 52.3.207.25452.3.207.2551,022
24552.3.208.0/2252.3.208.1 to 52.3.211.25452.3.211.2551,022
24652.3.212.0/2252.3.212.1 to 52.3.215.25452.3.215.2551,022
24752.3.216.0/2252.3.216.1 to 52.3.219.25452.3.219.2551,022
24852.3.220.0/2252.3.220.1 to 52.3.223.25452.3.223.2551,022
24952.3.224.0/2252.3.224.1 to 52.3.227.25452.3.227.2551,022
25052.3.228.0/2252.3.228.1 to 52.3.231.25452.3.231.2551,022
25152.3.232.0/2252.3.232.1 to 52.3.235.25452.3.235.2551,022
25252.3.236.0/2252.3.236.1 to 52.3.239.25452.3.239.2551,022
25352.3.240.0/2252.3.240.1 to 52.3.243.25452.3.243.2551,022
25452.3.244.0/2252.3.244.1 to 52.3.247.25452.3.247.2551,022
25552.3.248.0/2252.3.248.1 to 52.3.251.25452.3.251.2551,022
25652.3.252.0/2252.3.252.1 to 52.3.255.25452.3.255.2551,022

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.