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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.

Network26.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
26.0.0.0
Broadcast address
26.255.255.255
First usable
26.0.0.1
Last usable
26.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 1A000000 · Integer 436207616 to 452984831
Reverse DNS zone
26.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00011010..00000000.00000000.0000000026.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network00011010..00000000.00000000.0000000026.0.0.0
Broadcast00011010..11111111.11111111.1111111126.255.255.255
Split into smaller subnets/16
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

26.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
126.0.0.0/1626.0.0.1 to 26.0.255.25426.0.255.25565,534
226.1.0.0/1626.1.0.1 to 26.1.255.25426.1.255.25565,534
326.2.0.0/1626.2.0.1 to 26.2.255.25426.2.255.25565,534
426.3.0.0/1626.3.0.1 to 26.3.255.25426.3.255.25565,534
526.4.0.0/1626.4.0.1 to 26.4.255.25426.4.255.25565,534
626.5.0.0/1626.5.0.1 to 26.5.255.25426.5.255.25565,534
726.6.0.0/1626.6.0.1 to 26.6.255.25426.6.255.25565,534
826.7.0.0/1626.7.0.1 to 26.7.255.25426.7.255.25565,534
926.8.0.0/1626.8.0.1 to 26.8.255.25426.8.255.25565,534
1026.9.0.0/1626.9.0.1 to 26.9.255.25426.9.255.25565,534
1126.10.0.0/1626.10.0.1 to 26.10.255.25426.10.255.25565,534
1226.11.0.0/1626.11.0.1 to 26.11.255.25426.11.255.25565,534
1326.12.0.0/1626.12.0.1 to 26.12.255.25426.12.255.25565,534
1426.13.0.0/1626.13.0.1 to 26.13.255.25426.13.255.25565,534
1526.14.0.0/1626.14.0.1 to 26.14.255.25426.14.255.25565,534
1626.15.0.0/1626.15.0.1 to 26.15.255.25426.15.255.25565,534
1726.16.0.0/1626.16.0.1 to 26.16.255.25426.16.255.25565,534
1826.17.0.0/1626.17.0.1 to 26.17.255.25426.17.255.25565,534
1926.18.0.0/1626.18.0.1 to 26.18.255.25426.18.255.25565,534
2026.19.0.0/1626.19.0.1 to 26.19.255.25426.19.255.25565,534
2126.20.0.0/1626.20.0.1 to 26.20.255.25426.20.255.25565,534
2226.21.0.0/1626.21.0.1 to 26.21.255.25426.21.255.25565,534
2326.22.0.0/1626.22.0.1 to 26.22.255.25426.22.255.25565,534
2426.23.0.0/1626.23.0.1 to 26.23.255.25426.23.255.25565,534
2526.24.0.0/1626.24.0.1 to 26.24.255.25426.24.255.25565,534
2626.25.0.0/1626.25.0.1 to 26.25.255.25426.25.255.25565,534
2726.26.0.0/1626.26.0.1 to 26.26.255.25426.26.255.25565,534
2826.27.0.0/1626.27.0.1 to 26.27.255.25426.27.255.25565,534
2926.28.0.0/1626.28.0.1 to 26.28.255.25426.28.255.25565,534
3026.29.0.0/1626.29.0.1 to 26.29.255.25426.29.255.25565,534
3126.30.0.0/1626.30.0.1 to 26.30.255.25426.30.255.25565,534
3226.31.0.0/1626.31.0.1 to 26.31.255.25426.31.255.25565,534
3326.32.0.0/1626.32.0.1 to 26.32.255.25426.32.255.25565,534
3426.33.0.0/1626.33.0.1 to 26.33.255.25426.33.255.25565,534
3526.34.0.0/1626.34.0.1 to 26.34.255.25426.34.255.25565,534
3626.35.0.0/1626.35.0.1 to 26.35.255.25426.35.255.25565,534
3726.36.0.0/1626.36.0.1 to 26.36.255.25426.36.255.25565,534
3826.37.0.0/1626.37.0.1 to 26.37.255.25426.37.255.25565,534
3926.38.0.0/1626.38.0.1 to 26.38.255.25426.38.255.25565,534
4026.39.0.0/1626.39.0.1 to 26.39.255.25426.39.255.25565,534
4126.40.0.0/1626.40.0.1 to 26.40.255.25426.40.255.25565,534
4226.41.0.0/1626.41.0.1 to 26.41.255.25426.41.255.25565,534
4326.42.0.0/1626.42.0.1 to 26.42.255.25426.42.255.25565,534
4426.43.0.0/1626.43.0.1 to 26.43.255.25426.43.255.25565,534
4526.44.0.0/1626.44.0.1 to 26.44.255.25426.44.255.25565,534
4626.45.0.0/1626.45.0.1 to 26.45.255.25426.45.255.25565,534
4726.46.0.0/1626.46.0.1 to 26.46.255.25426.46.255.25565,534
4826.47.0.0/1626.47.0.1 to 26.47.255.25426.47.255.25565,534
4926.48.0.0/1626.48.0.1 to 26.48.255.25426.48.255.25565,534
5026.49.0.0/1626.49.0.1 to 26.49.255.25426.49.255.25565,534
5126.50.0.0/1626.50.0.1 to 26.50.255.25426.50.255.25565,534
5226.51.0.0/1626.51.0.1 to 26.51.255.25426.51.255.25565,534
5326.52.0.0/1626.52.0.1 to 26.52.255.25426.52.255.25565,534
5426.53.0.0/1626.53.0.1 to 26.53.255.25426.53.255.25565,534
5526.54.0.0/1626.54.0.1 to 26.54.255.25426.54.255.25565,534
5626.55.0.0/1626.55.0.1 to 26.55.255.25426.55.255.25565,534
5726.56.0.0/1626.56.0.1 to 26.56.255.25426.56.255.25565,534
5826.57.0.0/1626.57.0.1 to 26.57.255.25426.57.255.25565,534
5926.58.0.0/1626.58.0.1 to 26.58.255.25426.58.255.25565,534
6026.59.0.0/1626.59.0.1 to 26.59.255.25426.59.255.25565,534
6126.60.0.0/1626.60.0.1 to 26.60.255.25426.60.255.25565,534
6226.61.0.0/1626.61.0.1 to 26.61.255.25426.61.255.25565,534
6326.62.0.0/1626.62.0.1 to 26.62.255.25426.62.255.25565,534
6426.63.0.0/1626.63.0.1 to 26.63.255.25426.63.255.25565,534
6526.64.0.0/1626.64.0.1 to 26.64.255.25426.64.255.25565,534
6626.65.0.0/1626.65.0.1 to 26.65.255.25426.65.255.25565,534
6726.66.0.0/1626.66.0.1 to 26.66.255.25426.66.255.25565,534
6826.67.0.0/1626.67.0.1 to 26.67.255.25426.67.255.25565,534
6926.68.0.0/1626.68.0.1 to 26.68.255.25426.68.255.25565,534
7026.69.0.0/1626.69.0.1 to 26.69.255.25426.69.255.25565,534
7126.70.0.0/1626.70.0.1 to 26.70.255.25426.70.255.25565,534
7226.71.0.0/1626.71.0.1 to 26.71.255.25426.71.255.25565,534
7326.72.0.0/1626.72.0.1 to 26.72.255.25426.72.255.25565,534
7426.73.0.0/1626.73.0.1 to 26.73.255.25426.73.255.25565,534
7526.74.0.0/1626.74.0.1 to 26.74.255.25426.74.255.25565,534
7626.75.0.0/1626.75.0.1 to 26.75.255.25426.75.255.25565,534
7726.76.0.0/1626.76.0.1 to 26.76.255.25426.76.255.25565,534
7826.77.0.0/1626.77.0.1 to 26.77.255.25426.77.255.25565,534
7926.78.0.0/1626.78.0.1 to 26.78.255.25426.78.255.25565,534
8026.79.0.0/1626.79.0.1 to 26.79.255.25426.79.255.25565,534
8126.80.0.0/1626.80.0.1 to 26.80.255.25426.80.255.25565,534
8226.81.0.0/1626.81.0.1 to 26.81.255.25426.81.255.25565,534
8326.82.0.0/1626.82.0.1 to 26.82.255.25426.82.255.25565,534
8426.83.0.0/1626.83.0.1 to 26.83.255.25426.83.255.25565,534
8526.84.0.0/1626.84.0.1 to 26.84.255.25426.84.255.25565,534
8626.85.0.0/1626.85.0.1 to 26.85.255.25426.85.255.25565,534
8726.86.0.0/1626.86.0.1 to 26.86.255.25426.86.255.25565,534
8826.87.0.0/1626.87.0.1 to 26.87.255.25426.87.255.25565,534
8926.88.0.0/1626.88.0.1 to 26.88.255.25426.88.255.25565,534
9026.89.0.0/1626.89.0.1 to 26.89.255.25426.89.255.25565,534
9126.90.0.0/1626.90.0.1 to 26.90.255.25426.90.255.25565,534
9226.91.0.0/1626.91.0.1 to 26.91.255.25426.91.255.25565,534
9326.92.0.0/1626.92.0.1 to 26.92.255.25426.92.255.25565,534
9426.93.0.0/1626.93.0.1 to 26.93.255.25426.93.255.25565,534
9526.94.0.0/1626.94.0.1 to 26.94.255.25426.94.255.25565,534
9626.95.0.0/1626.95.0.1 to 26.95.255.25426.95.255.25565,534
9726.96.0.0/1626.96.0.1 to 26.96.255.25426.96.255.25565,534
9826.97.0.0/1626.97.0.1 to 26.97.255.25426.97.255.25565,534
9926.98.0.0/1626.98.0.1 to 26.98.255.25426.98.255.25565,534
10026.99.0.0/1626.99.0.1 to 26.99.255.25426.99.255.25565,534
10126.100.0.0/1626.100.0.1 to 26.100.255.25426.100.255.25565,534
10226.101.0.0/1626.101.0.1 to 26.101.255.25426.101.255.25565,534
10326.102.0.0/1626.102.0.1 to 26.102.255.25426.102.255.25565,534
10426.103.0.0/1626.103.0.1 to 26.103.255.25426.103.255.25565,534
10526.104.0.0/1626.104.0.1 to 26.104.255.25426.104.255.25565,534
10626.105.0.0/1626.105.0.1 to 26.105.255.25426.105.255.25565,534
10726.106.0.0/1626.106.0.1 to 26.106.255.25426.106.255.25565,534
10826.107.0.0/1626.107.0.1 to 26.107.255.25426.107.255.25565,534
10926.108.0.0/1626.108.0.1 to 26.108.255.25426.108.255.25565,534
11026.109.0.0/1626.109.0.1 to 26.109.255.25426.109.255.25565,534
11126.110.0.0/1626.110.0.1 to 26.110.255.25426.110.255.25565,534
11226.111.0.0/1626.111.0.1 to 26.111.255.25426.111.255.25565,534
11326.112.0.0/1626.112.0.1 to 26.112.255.25426.112.255.25565,534
11426.113.0.0/1626.113.0.1 to 26.113.255.25426.113.255.25565,534
11526.114.0.0/1626.114.0.1 to 26.114.255.25426.114.255.25565,534
11626.115.0.0/1626.115.0.1 to 26.115.255.25426.115.255.25565,534
11726.116.0.0/1626.116.0.1 to 26.116.255.25426.116.255.25565,534
11826.117.0.0/1626.117.0.1 to 26.117.255.25426.117.255.25565,534
11926.118.0.0/1626.118.0.1 to 26.118.255.25426.118.255.25565,534
12026.119.0.0/1626.119.0.1 to 26.119.255.25426.119.255.25565,534
12126.120.0.0/1626.120.0.1 to 26.120.255.25426.120.255.25565,534
12226.121.0.0/1626.121.0.1 to 26.121.255.25426.121.255.25565,534
12326.122.0.0/1626.122.0.1 to 26.122.255.25426.122.255.25565,534
12426.123.0.0/1626.123.0.1 to 26.123.255.25426.123.255.25565,534
12526.124.0.0/1626.124.0.1 to 26.124.255.25426.124.255.25565,534
12626.125.0.0/1626.125.0.1 to 26.125.255.25426.125.255.25565,534
12726.126.0.0/1626.126.0.1 to 26.126.255.25426.126.255.25565,534
12826.127.0.0/1626.127.0.1 to 26.127.255.25426.127.255.25565,534
12926.128.0.0/1626.128.0.1 to 26.128.255.25426.128.255.25565,534
13026.129.0.0/1626.129.0.1 to 26.129.255.25426.129.255.25565,534
13126.130.0.0/1626.130.0.1 to 26.130.255.25426.130.255.25565,534
13226.131.0.0/1626.131.0.1 to 26.131.255.25426.131.255.25565,534
13326.132.0.0/1626.132.0.1 to 26.132.255.25426.132.255.25565,534
13426.133.0.0/1626.133.0.1 to 26.133.255.25426.133.255.25565,534
13526.134.0.0/1626.134.0.1 to 26.134.255.25426.134.255.25565,534
13626.135.0.0/1626.135.0.1 to 26.135.255.25426.135.255.25565,534
13726.136.0.0/1626.136.0.1 to 26.136.255.25426.136.255.25565,534
13826.137.0.0/1626.137.0.1 to 26.137.255.25426.137.255.25565,534
13926.138.0.0/1626.138.0.1 to 26.138.255.25426.138.255.25565,534
14026.139.0.0/1626.139.0.1 to 26.139.255.25426.139.255.25565,534
14126.140.0.0/1626.140.0.1 to 26.140.255.25426.140.255.25565,534
14226.141.0.0/1626.141.0.1 to 26.141.255.25426.141.255.25565,534
14326.142.0.0/1626.142.0.1 to 26.142.255.25426.142.255.25565,534
14426.143.0.0/1626.143.0.1 to 26.143.255.25426.143.255.25565,534
14526.144.0.0/1626.144.0.1 to 26.144.255.25426.144.255.25565,534
14626.145.0.0/1626.145.0.1 to 26.145.255.25426.145.255.25565,534
14726.146.0.0/1626.146.0.1 to 26.146.255.25426.146.255.25565,534
14826.147.0.0/1626.147.0.1 to 26.147.255.25426.147.255.25565,534
14926.148.0.0/1626.148.0.1 to 26.148.255.25426.148.255.25565,534
15026.149.0.0/1626.149.0.1 to 26.149.255.25426.149.255.25565,534
15126.150.0.0/1626.150.0.1 to 26.150.255.25426.150.255.25565,534
15226.151.0.0/1626.151.0.1 to 26.151.255.25426.151.255.25565,534
15326.152.0.0/1626.152.0.1 to 26.152.255.25426.152.255.25565,534
15426.153.0.0/1626.153.0.1 to 26.153.255.25426.153.255.25565,534
15526.154.0.0/1626.154.0.1 to 26.154.255.25426.154.255.25565,534
15626.155.0.0/1626.155.0.1 to 26.155.255.25426.155.255.25565,534
15726.156.0.0/1626.156.0.1 to 26.156.255.25426.156.255.25565,534
15826.157.0.0/1626.157.0.1 to 26.157.255.25426.157.255.25565,534
15926.158.0.0/1626.158.0.1 to 26.158.255.25426.158.255.25565,534
16026.159.0.0/1626.159.0.1 to 26.159.255.25426.159.255.25565,534
16126.160.0.0/1626.160.0.1 to 26.160.255.25426.160.255.25565,534
16226.161.0.0/1626.161.0.1 to 26.161.255.25426.161.255.25565,534
16326.162.0.0/1626.162.0.1 to 26.162.255.25426.162.255.25565,534
16426.163.0.0/1626.163.0.1 to 26.163.255.25426.163.255.25565,534
16526.164.0.0/1626.164.0.1 to 26.164.255.25426.164.255.25565,534
16626.165.0.0/1626.165.0.1 to 26.165.255.25426.165.255.25565,534
16726.166.0.0/1626.166.0.1 to 26.166.255.25426.166.255.25565,534
16826.167.0.0/1626.167.0.1 to 26.167.255.25426.167.255.25565,534
16926.168.0.0/1626.168.0.1 to 26.168.255.25426.168.255.25565,534
17026.169.0.0/1626.169.0.1 to 26.169.255.25426.169.255.25565,534
17126.170.0.0/1626.170.0.1 to 26.170.255.25426.170.255.25565,534
17226.171.0.0/1626.171.0.1 to 26.171.255.25426.171.255.25565,534
17326.172.0.0/1626.172.0.1 to 26.172.255.25426.172.255.25565,534
17426.173.0.0/1626.173.0.1 to 26.173.255.25426.173.255.25565,534
17526.174.0.0/1626.174.0.1 to 26.174.255.25426.174.255.25565,534
17626.175.0.0/1626.175.0.1 to 26.175.255.25426.175.255.25565,534
17726.176.0.0/1626.176.0.1 to 26.176.255.25426.176.255.25565,534
17826.177.0.0/1626.177.0.1 to 26.177.255.25426.177.255.25565,534
17926.178.0.0/1626.178.0.1 to 26.178.255.25426.178.255.25565,534
18026.179.0.0/1626.179.0.1 to 26.179.255.25426.179.255.25565,534
18126.180.0.0/1626.180.0.1 to 26.180.255.25426.180.255.25565,534
18226.181.0.0/1626.181.0.1 to 26.181.255.25426.181.255.25565,534
18326.182.0.0/1626.182.0.1 to 26.182.255.25426.182.255.25565,534
18426.183.0.0/1626.183.0.1 to 26.183.255.25426.183.255.25565,534
18526.184.0.0/1626.184.0.1 to 26.184.255.25426.184.255.25565,534
18626.185.0.0/1626.185.0.1 to 26.185.255.25426.185.255.25565,534
18726.186.0.0/1626.186.0.1 to 26.186.255.25426.186.255.25565,534
18826.187.0.0/1626.187.0.1 to 26.187.255.25426.187.255.25565,534
18926.188.0.0/1626.188.0.1 to 26.188.255.25426.188.255.25565,534
19026.189.0.0/1626.189.0.1 to 26.189.255.25426.189.255.25565,534
19126.190.0.0/1626.190.0.1 to 26.190.255.25426.190.255.25565,534
19226.191.0.0/1626.191.0.1 to 26.191.255.25426.191.255.25565,534
19326.192.0.0/1626.192.0.1 to 26.192.255.25426.192.255.25565,534
19426.193.0.0/1626.193.0.1 to 26.193.255.25426.193.255.25565,534
19526.194.0.0/1626.194.0.1 to 26.194.255.25426.194.255.25565,534
19626.195.0.0/1626.195.0.1 to 26.195.255.25426.195.255.25565,534
19726.196.0.0/1626.196.0.1 to 26.196.255.25426.196.255.25565,534
19826.197.0.0/1626.197.0.1 to 26.197.255.25426.197.255.25565,534
19926.198.0.0/1626.198.0.1 to 26.198.255.25426.198.255.25565,534
20026.199.0.0/1626.199.0.1 to 26.199.255.25426.199.255.25565,534
20126.200.0.0/1626.200.0.1 to 26.200.255.25426.200.255.25565,534
20226.201.0.0/1626.201.0.1 to 26.201.255.25426.201.255.25565,534
20326.202.0.0/1626.202.0.1 to 26.202.255.25426.202.255.25565,534
20426.203.0.0/1626.203.0.1 to 26.203.255.25426.203.255.25565,534
20526.204.0.0/1626.204.0.1 to 26.204.255.25426.204.255.25565,534
20626.205.0.0/1626.205.0.1 to 26.205.255.25426.205.255.25565,534
20726.206.0.0/1626.206.0.1 to 26.206.255.25426.206.255.25565,534
20826.207.0.0/1626.207.0.1 to 26.207.255.25426.207.255.25565,534
20926.208.0.0/1626.208.0.1 to 26.208.255.25426.208.255.25565,534
21026.209.0.0/1626.209.0.1 to 26.209.255.25426.209.255.25565,534
21126.210.0.0/1626.210.0.1 to 26.210.255.25426.210.255.25565,534
21226.211.0.0/1626.211.0.1 to 26.211.255.25426.211.255.25565,534
21326.212.0.0/1626.212.0.1 to 26.212.255.25426.212.255.25565,534
21426.213.0.0/1626.213.0.1 to 26.213.255.25426.213.255.25565,534
21526.214.0.0/1626.214.0.1 to 26.214.255.25426.214.255.25565,534
21626.215.0.0/1626.215.0.1 to 26.215.255.25426.215.255.25565,534
21726.216.0.0/1626.216.0.1 to 26.216.255.25426.216.255.25565,534
21826.217.0.0/1626.217.0.1 to 26.217.255.25426.217.255.25565,534
21926.218.0.0/1626.218.0.1 to 26.218.255.25426.218.255.25565,534
22026.219.0.0/1626.219.0.1 to 26.219.255.25426.219.255.25565,534
22126.220.0.0/1626.220.0.1 to 26.220.255.25426.220.255.25565,534
22226.221.0.0/1626.221.0.1 to 26.221.255.25426.221.255.25565,534
22326.222.0.0/1626.222.0.1 to 26.222.255.25426.222.255.25565,534
22426.223.0.0/1626.223.0.1 to 26.223.255.25426.223.255.25565,534
22526.224.0.0/1626.224.0.1 to 26.224.255.25426.224.255.25565,534
22626.225.0.0/1626.225.0.1 to 26.225.255.25426.225.255.25565,534
22726.226.0.0/1626.226.0.1 to 26.226.255.25426.226.255.25565,534
22826.227.0.0/1626.227.0.1 to 26.227.255.25426.227.255.25565,534
22926.228.0.0/1626.228.0.1 to 26.228.255.25426.228.255.25565,534
23026.229.0.0/1626.229.0.1 to 26.229.255.25426.229.255.25565,534
23126.230.0.0/1626.230.0.1 to 26.230.255.25426.230.255.25565,534
23226.231.0.0/1626.231.0.1 to 26.231.255.25426.231.255.25565,534
23326.232.0.0/1626.232.0.1 to 26.232.255.25426.232.255.25565,534
23426.233.0.0/1626.233.0.1 to 26.233.255.25426.233.255.25565,534
23526.234.0.0/1626.234.0.1 to 26.234.255.25426.234.255.25565,534
23626.235.0.0/1626.235.0.1 to 26.235.255.25426.235.255.25565,534
23726.236.0.0/1626.236.0.1 to 26.236.255.25426.236.255.25565,534
23826.237.0.0/1626.237.0.1 to 26.237.255.25426.237.255.25565,534
23926.238.0.0/1626.238.0.1 to 26.238.255.25426.238.255.25565,534
24026.239.0.0/1626.239.0.1 to 26.239.255.25426.239.255.25565,534
24126.240.0.0/1626.240.0.1 to 26.240.255.25426.240.255.25565,534
24226.241.0.0/1626.241.0.1 to 26.241.255.25426.241.255.25565,534
24326.242.0.0/1626.242.0.1 to 26.242.255.25426.242.255.25565,534
24426.243.0.0/1626.243.0.1 to 26.243.255.25426.243.255.25565,534
24526.244.0.0/1626.244.0.1 to 26.244.255.25426.244.255.25565,534
24626.245.0.0/1626.245.0.1 to 26.245.255.25426.245.255.25565,534
24726.246.0.0/1626.246.0.1 to 26.246.255.25426.246.255.25565,534
24826.247.0.0/1626.247.0.1 to 26.247.255.25426.247.255.25565,534
24926.248.0.0/1626.248.0.1 to 26.248.255.25426.248.255.25565,534
25026.249.0.0/1626.249.0.1 to 26.249.255.25426.249.255.25565,534
25126.250.0.0/1626.250.0.1 to 26.250.255.25426.250.255.25565,534
25226.251.0.0/1626.251.0.1 to 26.251.255.25426.251.255.25565,534
25326.252.0.0/1626.252.0.1 to 26.252.255.25426.252.255.25565,534
25426.253.0.0/1626.253.0.1 to 26.253.255.25426.253.255.25565,534
25526.254.0.0/1626.254.0.1 to 26.254.255.25426.254.255.25565,534
25626.255.0.0/1626.255.0.1 to 26.255.255.25426.255.255.25565,534

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.