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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.

Network11.136.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
11.136.0.0
Broadcast address
11.143.255.255
First usable
11.136.0.1
Last usable
11.143.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 0B880000 · Integer 193462272 to 193986559
Reverse DNS zones
136.11.in-addr.arpa
137.11.in-addr.arpa
138.11.in-addr.arpa
139.11.in-addr.arpa
140.11.in-addr.arpa
141.11.in-addr.arpa
142.11.in-addr.arpa
143.11.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001011.10001000.00000000.0000000011.136.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network00001011.10001000.00000000.0000000011.136.0.0
Broadcast00001011.10001111.11111111.1111111111.143.255.255
Split into smaller subnets/23
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

11.136.0.0/13 makes 1,024 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
111.136.0.0/2311.136.0.1 to 11.136.1.25411.136.1.255510
211.136.2.0/2311.136.2.1 to 11.136.3.25411.136.3.255510
311.136.4.0/2311.136.4.1 to 11.136.5.25411.136.5.255510
411.136.6.0/2311.136.6.1 to 11.136.7.25411.136.7.255510
511.136.8.0/2311.136.8.1 to 11.136.9.25411.136.9.255510
611.136.10.0/2311.136.10.1 to 11.136.11.25411.136.11.255510
711.136.12.0/2311.136.12.1 to 11.136.13.25411.136.13.255510
811.136.14.0/2311.136.14.1 to 11.136.15.25411.136.15.255510
911.136.16.0/2311.136.16.1 to 11.136.17.25411.136.17.255510
1011.136.18.0/2311.136.18.1 to 11.136.19.25411.136.19.255510
1111.136.20.0/2311.136.20.1 to 11.136.21.25411.136.21.255510
1211.136.22.0/2311.136.22.1 to 11.136.23.25411.136.23.255510
1311.136.24.0/2311.136.24.1 to 11.136.25.25411.136.25.255510
1411.136.26.0/2311.136.26.1 to 11.136.27.25411.136.27.255510
1511.136.28.0/2311.136.28.1 to 11.136.29.25411.136.29.255510
1611.136.30.0/2311.136.30.1 to 11.136.31.25411.136.31.255510
1711.136.32.0/2311.136.32.1 to 11.136.33.25411.136.33.255510
1811.136.34.0/2311.136.34.1 to 11.136.35.25411.136.35.255510
1911.136.36.0/2311.136.36.1 to 11.136.37.25411.136.37.255510
2011.136.38.0/2311.136.38.1 to 11.136.39.25411.136.39.255510
2111.136.40.0/2311.136.40.1 to 11.136.41.25411.136.41.255510
2211.136.42.0/2311.136.42.1 to 11.136.43.25411.136.43.255510
2311.136.44.0/2311.136.44.1 to 11.136.45.25411.136.45.255510
2411.136.46.0/2311.136.46.1 to 11.136.47.25411.136.47.255510
2511.136.48.0/2311.136.48.1 to 11.136.49.25411.136.49.255510
2611.136.50.0/2311.136.50.1 to 11.136.51.25411.136.51.255510
2711.136.52.0/2311.136.52.1 to 11.136.53.25411.136.53.255510
2811.136.54.0/2311.136.54.1 to 11.136.55.25411.136.55.255510
2911.136.56.0/2311.136.56.1 to 11.136.57.25411.136.57.255510
3011.136.58.0/2311.136.58.1 to 11.136.59.25411.136.59.255510
3111.136.60.0/2311.136.60.1 to 11.136.61.25411.136.61.255510
3211.136.62.0/2311.136.62.1 to 11.136.63.25411.136.63.255510
3311.136.64.0/2311.136.64.1 to 11.136.65.25411.136.65.255510
3411.136.66.0/2311.136.66.1 to 11.136.67.25411.136.67.255510
3511.136.68.0/2311.136.68.1 to 11.136.69.25411.136.69.255510
3611.136.70.0/2311.136.70.1 to 11.136.71.25411.136.71.255510
3711.136.72.0/2311.136.72.1 to 11.136.73.25411.136.73.255510
3811.136.74.0/2311.136.74.1 to 11.136.75.25411.136.75.255510
3911.136.76.0/2311.136.76.1 to 11.136.77.25411.136.77.255510
4011.136.78.0/2311.136.78.1 to 11.136.79.25411.136.79.255510
4111.136.80.0/2311.136.80.1 to 11.136.81.25411.136.81.255510
4211.136.82.0/2311.136.82.1 to 11.136.83.25411.136.83.255510
4311.136.84.0/2311.136.84.1 to 11.136.85.25411.136.85.255510
4411.136.86.0/2311.136.86.1 to 11.136.87.25411.136.87.255510
4511.136.88.0/2311.136.88.1 to 11.136.89.25411.136.89.255510
4611.136.90.0/2311.136.90.1 to 11.136.91.25411.136.91.255510
4711.136.92.0/2311.136.92.1 to 11.136.93.25411.136.93.255510
4811.136.94.0/2311.136.94.1 to 11.136.95.25411.136.95.255510
4911.136.96.0/2311.136.96.1 to 11.136.97.25411.136.97.255510
5011.136.98.0/2311.136.98.1 to 11.136.99.25411.136.99.255510
5111.136.100.0/2311.136.100.1 to 11.136.101.25411.136.101.255510
5211.136.102.0/2311.136.102.1 to 11.136.103.25411.136.103.255510
5311.136.104.0/2311.136.104.1 to 11.136.105.25411.136.105.255510
5411.136.106.0/2311.136.106.1 to 11.136.107.25411.136.107.255510
5511.136.108.0/2311.136.108.1 to 11.136.109.25411.136.109.255510
5611.136.110.0/2311.136.110.1 to 11.136.111.25411.136.111.255510
5711.136.112.0/2311.136.112.1 to 11.136.113.25411.136.113.255510
5811.136.114.0/2311.136.114.1 to 11.136.115.25411.136.115.255510
5911.136.116.0/2311.136.116.1 to 11.136.117.25411.136.117.255510
6011.136.118.0/2311.136.118.1 to 11.136.119.25411.136.119.255510
6111.136.120.0/2311.136.120.1 to 11.136.121.25411.136.121.255510
6211.136.122.0/2311.136.122.1 to 11.136.123.25411.136.123.255510
6311.136.124.0/2311.136.124.1 to 11.136.125.25411.136.125.255510
6411.136.126.0/2311.136.126.1 to 11.136.127.25411.136.127.255510
6511.136.128.0/2311.136.128.1 to 11.136.129.25411.136.129.255510
6611.136.130.0/2311.136.130.1 to 11.136.131.25411.136.131.255510
6711.136.132.0/2311.136.132.1 to 11.136.133.25411.136.133.255510
6811.136.134.0/2311.136.134.1 to 11.136.135.25411.136.135.255510
6911.136.136.0/2311.136.136.1 to 11.136.137.25411.136.137.255510
7011.136.138.0/2311.136.138.1 to 11.136.139.25411.136.139.255510
7111.136.140.0/2311.136.140.1 to 11.136.141.25411.136.141.255510
7211.136.142.0/2311.136.142.1 to 11.136.143.25411.136.143.255510
7311.136.144.0/2311.136.144.1 to 11.136.145.25411.136.145.255510
7411.136.146.0/2311.136.146.1 to 11.136.147.25411.136.147.255510
7511.136.148.0/2311.136.148.1 to 11.136.149.25411.136.149.255510
7611.136.150.0/2311.136.150.1 to 11.136.151.25411.136.151.255510
7711.136.152.0/2311.136.152.1 to 11.136.153.25411.136.153.255510
7811.136.154.0/2311.136.154.1 to 11.136.155.25411.136.155.255510
7911.136.156.0/2311.136.156.1 to 11.136.157.25411.136.157.255510
8011.136.158.0/2311.136.158.1 to 11.136.159.25411.136.159.255510
8111.136.160.0/2311.136.160.1 to 11.136.161.25411.136.161.255510
8211.136.162.0/2311.136.162.1 to 11.136.163.25411.136.163.255510
8311.136.164.0/2311.136.164.1 to 11.136.165.25411.136.165.255510
8411.136.166.0/2311.136.166.1 to 11.136.167.25411.136.167.255510
8511.136.168.0/2311.136.168.1 to 11.136.169.25411.136.169.255510
8611.136.170.0/2311.136.170.1 to 11.136.171.25411.136.171.255510
8711.136.172.0/2311.136.172.1 to 11.136.173.25411.136.173.255510
8811.136.174.0/2311.136.174.1 to 11.136.175.25411.136.175.255510
8911.136.176.0/2311.136.176.1 to 11.136.177.25411.136.177.255510
9011.136.178.0/2311.136.178.1 to 11.136.179.25411.136.179.255510
9111.136.180.0/2311.136.180.1 to 11.136.181.25411.136.181.255510
9211.136.182.0/2311.136.182.1 to 11.136.183.25411.136.183.255510
9311.136.184.0/2311.136.184.1 to 11.136.185.25411.136.185.255510
9411.136.186.0/2311.136.186.1 to 11.136.187.25411.136.187.255510
9511.136.188.0/2311.136.188.1 to 11.136.189.25411.136.189.255510
9611.136.190.0/2311.136.190.1 to 11.136.191.25411.136.191.255510
9711.136.192.0/2311.136.192.1 to 11.136.193.25411.136.193.255510
9811.136.194.0/2311.136.194.1 to 11.136.195.25411.136.195.255510
9911.136.196.0/2311.136.196.1 to 11.136.197.25411.136.197.255510
10011.136.198.0/2311.136.198.1 to 11.136.199.25411.136.199.255510
10111.136.200.0/2311.136.200.1 to 11.136.201.25411.136.201.255510
10211.136.202.0/2311.136.202.1 to 11.136.203.25411.136.203.255510
10311.136.204.0/2311.136.204.1 to 11.136.205.25411.136.205.255510
10411.136.206.0/2311.136.206.1 to 11.136.207.25411.136.207.255510
10511.136.208.0/2311.136.208.1 to 11.136.209.25411.136.209.255510
10611.136.210.0/2311.136.210.1 to 11.136.211.25411.136.211.255510
10711.136.212.0/2311.136.212.1 to 11.136.213.25411.136.213.255510
10811.136.214.0/2311.136.214.1 to 11.136.215.25411.136.215.255510
10911.136.216.0/2311.136.216.1 to 11.136.217.25411.136.217.255510
11011.136.218.0/2311.136.218.1 to 11.136.219.25411.136.219.255510
11111.136.220.0/2311.136.220.1 to 11.136.221.25411.136.221.255510
11211.136.222.0/2311.136.222.1 to 11.136.223.25411.136.223.255510
11311.136.224.0/2311.136.224.1 to 11.136.225.25411.136.225.255510
11411.136.226.0/2311.136.226.1 to 11.136.227.25411.136.227.255510
11511.136.228.0/2311.136.228.1 to 11.136.229.25411.136.229.255510
11611.136.230.0/2311.136.230.1 to 11.136.231.25411.136.231.255510
11711.136.232.0/2311.136.232.1 to 11.136.233.25411.136.233.255510
11811.136.234.0/2311.136.234.1 to 11.136.235.25411.136.235.255510
11911.136.236.0/2311.136.236.1 to 11.136.237.25411.136.237.255510
12011.136.238.0/2311.136.238.1 to 11.136.239.25411.136.239.255510
12111.136.240.0/2311.136.240.1 to 11.136.241.25411.136.241.255510
12211.136.242.0/2311.136.242.1 to 11.136.243.25411.136.243.255510
12311.136.244.0/2311.136.244.1 to 11.136.245.25411.136.245.255510
12411.136.246.0/2311.136.246.1 to 11.136.247.25411.136.247.255510
12511.136.248.0/2311.136.248.1 to 11.136.249.25411.136.249.255510
12611.136.250.0/2311.136.250.1 to 11.136.251.25411.136.251.255510
12711.136.252.0/2311.136.252.1 to 11.136.253.25411.136.253.255510
12811.136.254.0/2311.136.254.1 to 11.136.255.25411.136.255.255510
12911.137.0.0/2311.137.0.1 to 11.137.1.25411.137.1.255510
13011.137.2.0/2311.137.2.1 to 11.137.3.25411.137.3.255510
13111.137.4.0/2311.137.4.1 to 11.137.5.25411.137.5.255510
13211.137.6.0/2311.137.6.1 to 11.137.7.25411.137.7.255510
13311.137.8.0/2311.137.8.1 to 11.137.9.25411.137.9.255510
13411.137.10.0/2311.137.10.1 to 11.137.11.25411.137.11.255510
13511.137.12.0/2311.137.12.1 to 11.137.13.25411.137.13.255510
13611.137.14.0/2311.137.14.1 to 11.137.15.25411.137.15.255510
13711.137.16.0/2311.137.16.1 to 11.137.17.25411.137.17.255510
13811.137.18.0/2311.137.18.1 to 11.137.19.25411.137.19.255510
13911.137.20.0/2311.137.20.1 to 11.137.21.25411.137.21.255510
14011.137.22.0/2311.137.22.1 to 11.137.23.25411.137.23.255510
14111.137.24.0/2311.137.24.1 to 11.137.25.25411.137.25.255510
14211.137.26.0/2311.137.26.1 to 11.137.27.25411.137.27.255510
14311.137.28.0/2311.137.28.1 to 11.137.29.25411.137.29.255510
14411.137.30.0/2311.137.30.1 to 11.137.31.25411.137.31.255510
14511.137.32.0/2311.137.32.1 to 11.137.33.25411.137.33.255510
14611.137.34.0/2311.137.34.1 to 11.137.35.25411.137.35.255510
14711.137.36.0/2311.137.36.1 to 11.137.37.25411.137.37.255510
14811.137.38.0/2311.137.38.1 to 11.137.39.25411.137.39.255510
14911.137.40.0/2311.137.40.1 to 11.137.41.25411.137.41.255510
15011.137.42.0/2311.137.42.1 to 11.137.43.25411.137.43.255510
15111.137.44.0/2311.137.44.1 to 11.137.45.25411.137.45.255510
15211.137.46.0/2311.137.46.1 to 11.137.47.25411.137.47.255510
15311.137.48.0/2311.137.48.1 to 11.137.49.25411.137.49.255510
15411.137.50.0/2311.137.50.1 to 11.137.51.25411.137.51.255510
15511.137.52.0/2311.137.52.1 to 11.137.53.25411.137.53.255510
15611.137.54.0/2311.137.54.1 to 11.137.55.25411.137.55.255510
15711.137.56.0/2311.137.56.1 to 11.137.57.25411.137.57.255510
15811.137.58.0/2311.137.58.1 to 11.137.59.25411.137.59.255510
15911.137.60.0/2311.137.60.1 to 11.137.61.25411.137.61.255510
16011.137.62.0/2311.137.62.1 to 11.137.63.25411.137.63.255510
16111.137.64.0/2311.137.64.1 to 11.137.65.25411.137.65.255510
16211.137.66.0/2311.137.66.1 to 11.137.67.25411.137.67.255510
16311.137.68.0/2311.137.68.1 to 11.137.69.25411.137.69.255510
16411.137.70.0/2311.137.70.1 to 11.137.71.25411.137.71.255510
16511.137.72.0/2311.137.72.1 to 11.137.73.25411.137.73.255510
16611.137.74.0/2311.137.74.1 to 11.137.75.25411.137.75.255510
16711.137.76.0/2311.137.76.1 to 11.137.77.25411.137.77.255510
16811.137.78.0/2311.137.78.1 to 11.137.79.25411.137.79.255510
16911.137.80.0/2311.137.80.1 to 11.137.81.25411.137.81.255510
17011.137.82.0/2311.137.82.1 to 11.137.83.25411.137.83.255510
17111.137.84.0/2311.137.84.1 to 11.137.85.25411.137.85.255510
17211.137.86.0/2311.137.86.1 to 11.137.87.25411.137.87.255510
17311.137.88.0/2311.137.88.1 to 11.137.89.25411.137.89.255510
17411.137.90.0/2311.137.90.1 to 11.137.91.25411.137.91.255510
17511.137.92.0/2311.137.92.1 to 11.137.93.25411.137.93.255510
17611.137.94.0/2311.137.94.1 to 11.137.95.25411.137.95.255510
17711.137.96.0/2311.137.96.1 to 11.137.97.25411.137.97.255510
17811.137.98.0/2311.137.98.1 to 11.137.99.25411.137.99.255510
17911.137.100.0/2311.137.100.1 to 11.137.101.25411.137.101.255510
18011.137.102.0/2311.137.102.1 to 11.137.103.25411.137.103.255510
18111.137.104.0/2311.137.104.1 to 11.137.105.25411.137.105.255510
18211.137.106.0/2311.137.106.1 to 11.137.107.25411.137.107.255510
18311.137.108.0/2311.137.108.1 to 11.137.109.25411.137.109.255510
18411.137.110.0/2311.137.110.1 to 11.137.111.25411.137.111.255510
18511.137.112.0/2311.137.112.1 to 11.137.113.25411.137.113.255510
18611.137.114.0/2311.137.114.1 to 11.137.115.25411.137.115.255510
18711.137.116.0/2311.137.116.1 to 11.137.117.25411.137.117.255510
18811.137.118.0/2311.137.118.1 to 11.137.119.25411.137.119.255510
18911.137.120.0/2311.137.120.1 to 11.137.121.25411.137.121.255510
19011.137.122.0/2311.137.122.1 to 11.137.123.25411.137.123.255510
19111.137.124.0/2311.137.124.1 to 11.137.125.25411.137.125.255510
19211.137.126.0/2311.137.126.1 to 11.137.127.25411.137.127.255510
19311.137.128.0/2311.137.128.1 to 11.137.129.25411.137.129.255510
19411.137.130.0/2311.137.130.1 to 11.137.131.25411.137.131.255510
19511.137.132.0/2311.137.132.1 to 11.137.133.25411.137.133.255510
19611.137.134.0/2311.137.134.1 to 11.137.135.25411.137.135.255510
19711.137.136.0/2311.137.136.1 to 11.137.137.25411.137.137.255510
19811.137.138.0/2311.137.138.1 to 11.137.139.25411.137.139.255510
19911.137.140.0/2311.137.140.1 to 11.137.141.25411.137.141.255510
20011.137.142.0/2311.137.142.1 to 11.137.143.25411.137.143.255510
20111.137.144.0/2311.137.144.1 to 11.137.145.25411.137.145.255510
20211.137.146.0/2311.137.146.1 to 11.137.147.25411.137.147.255510
20311.137.148.0/2311.137.148.1 to 11.137.149.25411.137.149.255510
20411.137.150.0/2311.137.150.1 to 11.137.151.25411.137.151.255510
20511.137.152.0/2311.137.152.1 to 11.137.153.25411.137.153.255510
20611.137.154.0/2311.137.154.1 to 11.137.155.25411.137.155.255510
20711.137.156.0/2311.137.156.1 to 11.137.157.25411.137.157.255510
20811.137.158.0/2311.137.158.1 to 11.137.159.25411.137.159.255510
20911.137.160.0/2311.137.160.1 to 11.137.161.25411.137.161.255510
21011.137.162.0/2311.137.162.1 to 11.137.163.25411.137.163.255510
21111.137.164.0/2311.137.164.1 to 11.137.165.25411.137.165.255510
21211.137.166.0/2311.137.166.1 to 11.137.167.25411.137.167.255510
21311.137.168.0/2311.137.168.1 to 11.137.169.25411.137.169.255510
21411.137.170.0/2311.137.170.1 to 11.137.171.25411.137.171.255510
21511.137.172.0/2311.137.172.1 to 11.137.173.25411.137.173.255510
21611.137.174.0/2311.137.174.1 to 11.137.175.25411.137.175.255510
21711.137.176.0/2311.137.176.1 to 11.137.177.25411.137.177.255510
21811.137.178.0/2311.137.178.1 to 11.137.179.25411.137.179.255510
21911.137.180.0/2311.137.180.1 to 11.137.181.25411.137.181.255510
22011.137.182.0/2311.137.182.1 to 11.137.183.25411.137.183.255510
22111.137.184.0/2311.137.184.1 to 11.137.185.25411.137.185.255510
22211.137.186.0/2311.137.186.1 to 11.137.187.25411.137.187.255510
22311.137.188.0/2311.137.188.1 to 11.137.189.25411.137.189.255510
22411.137.190.0/2311.137.190.1 to 11.137.191.25411.137.191.255510
22511.137.192.0/2311.137.192.1 to 11.137.193.25411.137.193.255510
22611.137.194.0/2311.137.194.1 to 11.137.195.25411.137.195.255510
22711.137.196.0/2311.137.196.1 to 11.137.197.25411.137.197.255510
22811.137.198.0/2311.137.198.1 to 11.137.199.25411.137.199.255510
22911.137.200.0/2311.137.200.1 to 11.137.201.25411.137.201.255510
23011.137.202.0/2311.137.202.1 to 11.137.203.25411.137.203.255510
23111.137.204.0/2311.137.204.1 to 11.137.205.25411.137.205.255510
23211.137.206.0/2311.137.206.1 to 11.137.207.25411.137.207.255510
23311.137.208.0/2311.137.208.1 to 11.137.209.25411.137.209.255510
23411.137.210.0/2311.137.210.1 to 11.137.211.25411.137.211.255510
23511.137.212.0/2311.137.212.1 to 11.137.213.25411.137.213.255510
23611.137.214.0/2311.137.214.1 to 11.137.215.25411.137.215.255510
23711.137.216.0/2311.137.216.1 to 11.137.217.25411.137.217.255510
23811.137.218.0/2311.137.218.1 to 11.137.219.25411.137.219.255510
23911.137.220.0/2311.137.220.1 to 11.137.221.25411.137.221.255510
24011.137.222.0/2311.137.222.1 to 11.137.223.25411.137.223.255510
24111.137.224.0/2311.137.224.1 to 11.137.225.25411.137.225.255510
24211.137.226.0/2311.137.226.1 to 11.137.227.25411.137.227.255510
24311.137.228.0/2311.137.228.1 to 11.137.229.25411.137.229.255510
24411.137.230.0/2311.137.230.1 to 11.137.231.25411.137.231.255510
24511.137.232.0/2311.137.232.1 to 11.137.233.25411.137.233.255510
24611.137.234.0/2311.137.234.1 to 11.137.235.25411.137.235.255510
24711.137.236.0/2311.137.236.1 to 11.137.237.25411.137.237.255510
24811.137.238.0/2311.137.238.1 to 11.137.239.25411.137.239.255510
24911.137.240.0/2311.137.240.1 to 11.137.241.25411.137.241.255510
25011.137.242.0/2311.137.242.1 to 11.137.243.25411.137.243.255510
25111.137.244.0/2311.137.244.1 to 11.137.245.25411.137.245.255510
25211.137.246.0/2311.137.246.1 to 11.137.247.25411.137.247.255510
25311.137.248.0/2311.137.248.1 to 11.137.249.25411.137.249.255510
25411.137.250.0/2311.137.250.1 to 11.137.251.25411.137.251.255510
25511.137.252.0/2311.137.252.1 to 11.137.253.25411.137.253.255510
25611.137.254.0/2311.137.254.1 to 11.137.255.25411.137.255.255510

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.