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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.

Network26.0.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
26.0.0.0
Broadcast address
26.63.255.255
First usable
26.0.0.1
Last usable
26.63.255.254
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 1A000000 · Integer 436207616 to 440401919
Reverse DNS zones
0.26.in-addr.arpa
1.26.in-addr.arpa
2.26.in-addr.arpa
3.26.in-addr.arpa
4.26.in-addr.arpa
5.26.in-addr.arpa
6.26.in-addr.arpa
7.26.in-addr.arpa
8.26.in-addr.arpa
9.26.in-addr.arpa
10.26.in-addr.arpa
11.26.in-addr.arpa
12.26.in-addr.arpa
13.26.in-addr.arpa
14.26.in-addr.arpa
15.26.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
Address00011010.00000000.00000000.0000000026.0.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00011010.00000000.00000000.0000000026.0.0.0
Broadcast00011010.00111111.11111111.1111111126.63.255.255
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)

26.0.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
126.0.0.0/2226.0.0.1 to 26.0.3.25426.0.3.2551,022
226.0.4.0/2226.0.4.1 to 26.0.7.25426.0.7.2551,022
326.0.8.0/2226.0.8.1 to 26.0.11.25426.0.11.2551,022
426.0.12.0/2226.0.12.1 to 26.0.15.25426.0.15.2551,022
526.0.16.0/2226.0.16.1 to 26.0.19.25426.0.19.2551,022
626.0.20.0/2226.0.20.1 to 26.0.23.25426.0.23.2551,022
726.0.24.0/2226.0.24.1 to 26.0.27.25426.0.27.2551,022
826.0.28.0/2226.0.28.1 to 26.0.31.25426.0.31.2551,022
926.0.32.0/2226.0.32.1 to 26.0.35.25426.0.35.2551,022
1026.0.36.0/2226.0.36.1 to 26.0.39.25426.0.39.2551,022
1126.0.40.0/2226.0.40.1 to 26.0.43.25426.0.43.2551,022
1226.0.44.0/2226.0.44.1 to 26.0.47.25426.0.47.2551,022
1326.0.48.0/2226.0.48.1 to 26.0.51.25426.0.51.2551,022
1426.0.52.0/2226.0.52.1 to 26.0.55.25426.0.55.2551,022
1526.0.56.0/2226.0.56.1 to 26.0.59.25426.0.59.2551,022
1626.0.60.0/2226.0.60.1 to 26.0.63.25426.0.63.2551,022
1726.0.64.0/2226.0.64.1 to 26.0.67.25426.0.67.2551,022
1826.0.68.0/2226.0.68.1 to 26.0.71.25426.0.71.2551,022
1926.0.72.0/2226.0.72.1 to 26.0.75.25426.0.75.2551,022
2026.0.76.0/2226.0.76.1 to 26.0.79.25426.0.79.2551,022
2126.0.80.0/2226.0.80.1 to 26.0.83.25426.0.83.2551,022
2226.0.84.0/2226.0.84.1 to 26.0.87.25426.0.87.2551,022
2326.0.88.0/2226.0.88.1 to 26.0.91.25426.0.91.2551,022
2426.0.92.0/2226.0.92.1 to 26.0.95.25426.0.95.2551,022
2526.0.96.0/2226.0.96.1 to 26.0.99.25426.0.99.2551,022
2626.0.100.0/2226.0.100.1 to 26.0.103.25426.0.103.2551,022
2726.0.104.0/2226.0.104.1 to 26.0.107.25426.0.107.2551,022
2826.0.108.0/2226.0.108.1 to 26.0.111.25426.0.111.2551,022
2926.0.112.0/2226.0.112.1 to 26.0.115.25426.0.115.2551,022
3026.0.116.0/2226.0.116.1 to 26.0.119.25426.0.119.2551,022
3126.0.120.0/2226.0.120.1 to 26.0.123.25426.0.123.2551,022
3226.0.124.0/2226.0.124.1 to 26.0.127.25426.0.127.2551,022
3326.0.128.0/2226.0.128.1 to 26.0.131.25426.0.131.2551,022
3426.0.132.0/2226.0.132.1 to 26.0.135.25426.0.135.2551,022
3526.0.136.0/2226.0.136.1 to 26.0.139.25426.0.139.2551,022
3626.0.140.0/2226.0.140.1 to 26.0.143.25426.0.143.2551,022
3726.0.144.0/2226.0.144.1 to 26.0.147.25426.0.147.2551,022
3826.0.148.0/2226.0.148.1 to 26.0.151.25426.0.151.2551,022
3926.0.152.0/2226.0.152.1 to 26.0.155.25426.0.155.2551,022
4026.0.156.0/2226.0.156.1 to 26.0.159.25426.0.159.2551,022
4126.0.160.0/2226.0.160.1 to 26.0.163.25426.0.163.2551,022
4226.0.164.0/2226.0.164.1 to 26.0.167.25426.0.167.2551,022
4326.0.168.0/2226.0.168.1 to 26.0.171.25426.0.171.2551,022
4426.0.172.0/2226.0.172.1 to 26.0.175.25426.0.175.2551,022
4526.0.176.0/2226.0.176.1 to 26.0.179.25426.0.179.2551,022
4626.0.180.0/2226.0.180.1 to 26.0.183.25426.0.183.2551,022
4726.0.184.0/2226.0.184.1 to 26.0.187.25426.0.187.2551,022
4826.0.188.0/2226.0.188.1 to 26.0.191.25426.0.191.2551,022
4926.0.192.0/2226.0.192.1 to 26.0.195.25426.0.195.2551,022
5026.0.196.0/2226.0.196.1 to 26.0.199.25426.0.199.2551,022
5126.0.200.0/2226.0.200.1 to 26.0.203.25426.0.203.2551,022
5226.0.204.0/2226.0.204.1 to 26.0.207.25426.0.207.2551,022
5326.0.208.0/2226.0.208.1 to 26.0.211.25426.0.211.2551,022
5426.0.212.0/2226.0.212.1 to 26.0.215.25426.0.215.2551,022
5526.0.216.0/2226.0.216.1 to 26.0.219.25426.0.219.2551,022
5626.0.220.0/2226.0.220.1 to 26.0.223.25426.0.223.2551,022
5726.0.224.0/2226.0.224.1 to 26.0.227.25426.0.227.2551,022
5826.0.228.0/2226.0.228.1 to 26.0.231.25426.0.231.2551,022
5926.0.232.0/2226.0.232.1 to 26.0.235.25426.0.235.2551,022
6026.0.236.0/2226.0.236.1 to 26.0.239.25426.0.239.2551,022
6126.0.240.0/2226.0.240.1 to 26.0.243.25426.0.243.2551,022
6226.0.244.0/2226.0.244.1 to 26.0.247.25426.0.247.2551,022
6326.0.248.0/2226.0.248.1 to 26.0.251.25426.0.251.2551,022
6426.0.252.0/2226.0.252.1 to 26.0.255.25426.0.255.2551,022
6526.1.0.0/2226.1.0.1 to 26.1.3.25426.1.3.2551,022
6626.1.4.0/2226.1.4.1 to 26.1.7.25426.1.7.2551,022
6726.1.8.0/2226.1.8.1 to 26.1.11.25426.1.11.2551,022
6826.1.12.0/2226.1.12.1 to 26.1.15.25426.1.15.2551,022
6926.1.16.0/2226.1.16.1 to 26.1.19.25426.1.19.2551,022
7026.1.20.0/2226.1.20.1 to 26.1.23.25426.1.23.2551,022
7126.1.24.0/2226.1.24.1 to 26.1.27.25426.1.27.2551,022
7226.1.28.0/2226.1.28.1 to 26.1.31.25426.1.31.2551,022
7326.1.32.0/2226.1.32.1 to 26.1.35.25426.1.35.2551,022
7426.1.36.0/2226.1.36.1 to 26.1.39.25426.1.39.2551,022
7526.1.40.0/2226.1.40.1 to 26.1.43.25426.1.43.2551,022
7626.1.44.0/2226.1.44.1 to 26.1.47.25426.1.47.2551,022
7726.1.48.0/2226.1.48.1 to 26.1.51.25426.1.51.2551,022
7826.1.52.0/2226.1.52.1 to 26.1.55.25426.1.55.2551,022
7926.1.56.0/2226.1.56.1 to 26.1.59.25426.1.59.2551,022
8026.1.60.0/2226.1.60.1 to 26.1.63.25426.1.63.2551,022
8126.1.64.0/2226.1.64.1 to 26.1.67.25426.1.67.2551,022
8226.1.68.0/2226.1.68.1 to 26.1.71.25426.1.71.2551,022
8326.1.72.0/2226.1.72.1 to 26.1.75.25426.1.75.2551,022
8426.1.76.0/2226.1.76.1 to 26.1.79.25426.1.79.2551,022
8526.1.80.0/2226.1.80.1 to 26.1.83.25426.1.83.2551,022
8626.1.84.0/2226.1.84.1 to 26.1.87.25426.1.87.2551,022
8726.1.88.0/2226.1.88.1 to 26.1.91.25426.1.91.2551,022
8826.1.92.0/2226.1.92.1 to 26.1.95.25426.1.95.2551,022
8926.1.96.0/2226.1.96.1 to 26.1.99.25426.1.99.2551,022
9026.1.100.0/2226.1.100.1 to 26.1.103.25426.1.103.2551,022
9126.1.104.0/2226.1.104.1 to 26.1.107.25426.1.107.2551,022
9226.1.108.0/2226.1.108.1 to 26.1.111.25426.1.111.2551,022
9326.1.112.0/2226.1.112.1 to 26.1.115.25426.1.115.2551,022
9426.1.116.0/2226.1.116.1 to 26.1.119.25426.1.119.2551,022
9526.1.120.0/2226.1.120.1 to 26.1.123.25426.1.123.2551,022
9626.1.124.0/2226.1.124.1 to 26.1.127.25426.1.127.2551,022
9726.1.128.0/2226.1.128.1 to 26.1.131.25426.1.131.2551,022
9826.1.132.0/2226.1.132.1 to 26.1.135.25426.1.135.2551,022
9926.1.136.0/2226.1.136.1 to 26.1.139.25426.1.139.2551,022
10026.1.140.0/2226.1.140.1 to 26.1.143.25426.1.143.2551,022
10126.1.144.0/2226.1.144.1 to 26.1.147.25426.1.147.2551,022
10226.1.148.0/2226.1.148.1 to 26.1.151.25426.1.151.2551,022
10326.1.152.0/2226.1.152.1 to 26.1.155.25426.1.155.2551,022
10426.1.156.0/2226.1.156.1 to 26.1.159.25426.1.159.2551,022
10526.1.160.0/2226.1.160.1 to 26.1.163.25426.1.163.2551,022
10626.1.164.0/2226.1.164.1 to 26.1.167.25426.1.167.2551,022
10726.1.168.0/2226.1.168.1 to 26.1.171.25426.1.171.2551,022
10826.1.172.0/2226.1.172.1 to 26.1.175.25426.1.175.2551,022
10926.1.176.0/2226.1.176.1 to 26.1.179.25426.1.179.2551,022
11026.1.180.0/2226.1.180.1 to 26.1.183.25426.1.183.2551,022
11126.1.184.0/2226.1.184.1 to 26.1.187.25426.1.187.2551,022
11226.1.188.0/2226.1.188.1 to 26.1.191.25426.1.191.2551,022
11326.1.192.0/2226.1.192.1 to 26.1.195.25426.1.195.2551,022
11426.1.196.0/2226.1.196.1 to 26.1.199.25426.1.199.2551,022
11526.1.200.0/2226.1.200.1 to 26.1.203.25426.1.203.2551,022
11626.1.204.0/2226.1.204.1 to 26.1.207.25426.1.207.2551,022
11726.1.208.0/2226.1.208.1 to 26.1.211.25426.1.211.2551,022
11826.1.212.0/2226.1.212.1 to 26.1.215.25426.1.215.2551,022
11926.1.216.0/2226.1.216.1 to 26.1.219.25426.1.219.2551,022
12026.1.220.0/2226.1.220.1 to 26.1.223.25426.1.223.2551,022
12126.1.224.0/2226.1.224.1 to 26.1.227.25426.1.227.2551,022
12226.1.228.0/2226.1.228.1 to 26.1.231.25426.1.231.2551,022
12326.1.232.0/2226.1.232.1 to 26.1.235.25426.1.235.2551,022
12426.1.236.0/2226.1.236.1 to 26.1.239.25426.1.239.2551,022
12526.1.240.0/2226.1.240.1 to 26.1.243.25426.1.243.2551,022
12626.1.244.0/2226.1.244.1 to 26.1.247.25426.1.247.2551,022
12726.1.248.0/2226.1.248.1 to 26.1.251.25426.1.251.2551,022
12826.1.252.0/2226.1.252.1 to 26.1.255.25426.1.255.2551,022
12926.2.0.0/2226.2.0.1 to 26.2.3.25426.2.3.2551,022
13026.2.4.0/2226.2.4.1 to 26.2.7.25426.2.7.2551,022
13126.2.8.0/2226.2.8.1 to 26.2.11.25426.2.11.2551,022
13226.2.12.0/2226.2.12.1 to 26.2.15.25426.2.15.2551,022
13326.2.16.0/2226.2.16.1 to 26.2.19.25426.2.19.2551,022
13426.2.20.0/2226.2.20.1 to 26.2.23.25426.2.23.2551,022
13526.2.24.0/2226.2.24.1 to 26.2.27.25426.2.27.2551,022
13626.2.28.0/2226.2.28.1 to 26.2.31.25426.2.31.2551,022
13726.2.32.0/2226.2.32.1 to 26.2.35.25426.2.35.2551,022
13826.2.36.0/2226.2.36.1 to 26.2.39.25426.2.39.2551,022
13926.2.40.0/2226.2.40.1 to 26.2.43.25426.2.43.2551,022
14026.2.44.0/2226.2.44.1 to 26.2.47.25426.2.47.2551,022
14126.2.48.0/2226.2.48.1 to 26.2.51.25426.2.51.2551,022
14226.2.52.0/2226.2.52.1 to 26.2.55.25426.2.55.2551,022
14326.2.56.0/2226.2.56.1 to 26.2.59.25426.2.59.2551,022
14426.2.60.0/2226.2.60.1 to 26.2.63.25426.2.63.2551,022
14526.2.64.0/2226.2.64.1 to 26.2.67.25426.2.67.2551,022
14626.2.68.0/2226.2.68.1 to 26.2.71.25426.2.71.2551,022
14726.2.72.0/2226.2.72.1 to 26.2.75.25426.2.75.2551,022
14826.2.76.0/2226.2.76.1 to 26.2.79.25426.2.79.2551,022
14926.2.80.0/2226.2.80.1 to 26.2.83.25426.2.83.2551,022
15026.2.84.0/2226.2.84.1 to 26.2.87.25426.2.87.2551,022
15126.2.88.0/2226.2.88.1 to 26.2.91.25426.2.91.2551,022
15226.2.92.0/2226.2.92.1 to 26.2.95.25426.2.95.2551,022
15326.2.96.0/2226.2.96.1 to 26.2.99.25426.2.99.2551,022
15426.2.100.0/2226.2.100.1 to 26.2.103.25426.2.103.2551,022
15526.2.104.0/2226.2.104.1 to 26.2.107.25426.2.107.2551,022
15626.2.108.0/2226.2.108.1 to 26.2.111.25426.2.111.2551,022
15726.2.112.0/2226.2.112.1 to 26.2.115.25426.2.115.2551,022
15826.2.116.0/2226.2.116.1 to 26.2.119.25426.2.119.2551,022
15926.2.120.0/2226.2.120.1 to 26.2.123.25426.2.123.2551,022
16026.2.124.0/2226.2.124.1 to 26.2.127.25426.2.127.2551,022
16126.2.128.0/2226.2.128.1 to 26.2.131.25426.2.131.2551,022
16226.2.132.0/2226.2.132.1 to 26.2.135.25426.2.135.2551,022
16326.2.136.0/2226.2.136.1 to 26.2.139.25426.2.139.2551,022
16426.2.140.0/2226.2.140.1 to 26.2.143.25426.2.143.2551,022
16526.2.144.0/2226.2.144.1 to 26.2.147.25426.2.147.2551,022
16626.2.148.0/2226.2.148.1 to 26.2.151.25426.2.151.2551,022
16726.2.152.0/2226.2.152.1 to 26.2.155.25426.2.155.2551,022
16826.2.156.0/2226.2.156.1 to 26.2.159.25426.2.159.2551,022
16926.2.160.0/2226.2.160.1 to 26.2.163.25426.2.163.2551,022
17026.2.164.0/2226.2.164.1 to 26.2.167.25426.2.167.2551,022
17126.2.168.0/2226.2.168.1 to 26.2.171.25426.2.171.2551,022
17226.2.172.0/2226.2.172.1 to 26.2.175.25426.2.175.2551,022
17326.2.176.0/2226.2.176.1 to 26.2.179.25426.2.179.2551,022
17426.2.180.0/2226.2.180.1 to 26.2.183.25426.2.183.2551,022
17526.2.184.0/2226.2.184.1 to 26.2.187.25426.2.187.2551,022
17626.2.188.0/2226.2.188.1 to 26.2.191.25426.2.191.2551,022
17726.2.192.0/2226.2.192.1 to 26.2.195.25426.2.195.2551,022
17826.2.196.0/2226.2.196.1 to 26.2.199.25426.2.199.2551,022
17926.2.200.0/2226.2.200.1 to 26.2.203.25426.2.203.2551,022
18026.2.204.0/2226.2.204.1 to 26.2.207.25426.2.207.2551,022
18126.2.208.0/2226.2.208.1 to 26.2.211.25426.2.211.2551,022
18226.2.212.0/2226.2.212.1 to 26.2.215.25426.2.215.2551,022
18326.2.216.0/2226.2.216.1 to 26.2.219.25426.2.219.2551,022
18426.2.220.0/2226.2.220.1 to 26.2.223.25426.2.223.2551,022
18526.2.224.0/2226.2.224.1 to 26.2.227.25426.2.227.2551,022
18626.2.228.0/2226.2.228.1 to 26.2.231.25426.2.231.2551,022
18726.2.232.0/2226.2.232.1 to 26.2.235.25426.2.235.2551,022
18826.2.236.0/2226.2.236.1 to 26.2.239.25426.2.239.2551,022
18926.2.240.0/2226.2.240.1 to 26.2.243.25426.2.243.2551,022
19026.2.244.0/2226.2.244.1 to 26.2.247.25426.2.247.2551,022
19126.2.248.0/2226.2.248.1 to 26.2.251.25426.2.251.2551,022
19226.2.252.0/2226.2.252.1 to 26.2.255.25426.2.255.2551,022
19326.3.0.0/2226.3.0.1 to 26.3.3.25426.3.3.2551,022
19426.3.4.0/2226.3.4.1 to 26.3.7.25426.3.7.2551,022
19526.3.8.0/2226.3.8.1 to 26.3.11.25426.3.11.2551,022
19626.3.12.0/2226.3.12.1 to 26.3.15.25426.3.15.2551,022
19726.3.16.0/2226.3.16.1 to 26.3.19.25426.3.19.2551,022
19826.3.20.0/2226.3.20.1 to 26.3.23.25426.3.23.2551,022
19926.3.24.0/2226.3.24.1 to 26.3.27.25426.3.27.2551,022
20026.3.28.0/2226.3.28.1 to 26.3.31.25426.3.31.2551,022
20126.3.32.0/2226.3.32.1 to 26.3.35.25426.3.35.2551,022
20226.3.36.0/2226.3.36.1 to 26.3.39.25426.3.39.2551,022
20326.3.40.0/2226.3.40.1 to 26.3.43.25426.3.43.2551,022
20426.3.44.0/2226.3.44.1 to 26.3.47.25426.3.47.2551,022
20526.3.48.0/2226.3.48.1 to 26.3.51.25426.3.51.2551,022
20626.3.52.0/2226.3.52.1 to 26.3.55.25426.3.55.2551,022
20726.3.56.0/2226.3.56.1 to 26.3.59.25426.3.59.2551,022
20826.3.60.0/2226.3.60.1 to 26.3.63.25426.3.63.2551,022
20926.3.64.0/2226.3.64.1 to 26.3.67.25426.3.67.2551,022
21026.3.68.0/2226.3.68.1 to 26.3.71.25426.3.71.2551,022
21126.3.72.0/2226.3.72.1 to 26.3.75.25426.3.75.2551,022
21226.3.76.0/2226.3.76.1 to 26.3.79.25426.3.79.2551,022
21326.3.80.0/2226.3.80.1 to 26.3.83.25426.3.83.2551,022
21426.3.84.0/2226.3.84.1 to 26.3.87.25426.3.87.2551,022
21526.3.88.0/2226.3.88.1 to 26.3.91.25426.3.91.2551,022
21626.3.92.0/2226.3.92.1 to 26.3.95.25426.3.95.2551,022
21726.3.96.0/2226.3.96.1 to 26.3.99.25426.3.99.2551,022
21826.3.100.0/2226.3.100.1 to 26.3.103.25426.3.103.2551,022
21926.3.104.0/2226.3.104.1 to 26.3.107.25426.3.107.2551,022
22026.3.108.0/2226.3.108.1 to 26.3.111.25426.3.111.2551,022
22126.3.112.0/2226.3.112.1 to 26.3.115.25426.3.115.2551,022
22226.3.116.0/2226.3.116.1 to 26.3.119.25426.3.119.2551,022
22326.3.120.0/2226.3.120.1 to 26.3.123.25426.3.123.2551,022
22426.3.124.0/2226.3.124.1 to 26.3.127.25426.3.127.2551,022
22526.3.128.0/2226.3.128.1 to 26.3.131.25426.3.131.2551,022
22626.3.132.0/2226.3.132.1 to 26.3.135.25426.3.135.2551,022
22726.3.136.0/2226.3.136.1 to 26.3.139.25426.3.139.2551,022
22826.3.140.0/2226.3.140.1 to 26.3.143.25426.3.143.2551,022
22926.3.144.0/2226.3.144.1 to 26.3.147.25426.3.147.2551,022
23026.3.148.0/2226.3.148.1 to 26.3.151.25426.3.151.2551,022
23126.3.152.0/2226.3.152.1 to 26.3.155.25426.3.155.2551,022
23226.3.156.0/2226.3.156.1 to 26.3.159.25426.3.159.2551,022
23326.3.160.0/2226.3.160.1 to 26.3.163.25426.3.163.2551,022
23426.3.164.0/2226.3.164.1 to 26.3.167.25426.3.167.2551,022
23526.3.168.0/2226.3.168.1 to 26.3.171.25426.3.171.2551,022
23626.3.172.0/2226.3.172.1 to 26.3.175.25426.3.175.2551,022
23726.3.176.0/2226.3.176.1 to 26.3.179.25426.3.179.2551,022
23826.3.180.0/2226.3.180.1 to 26.3.183.25426.3.183.2551,022
23926.3.184.0/2226.3.184.1 to 26.3.187.25426.3.187.2551,022
24026.3.188.0/2226.3.188.1 to 26.3.191.25426.3.191.2551,022
24126.3.192.0/2226.3.192.1 to 26.3.195.25426.3.195.2551,022
24226.3.196.0/2226.3.196.1 to 26.3.199.25426.3.199.2551,022
24326.3.200.0/2226.3.200.1 to 26.3.203.25426.3.203.2551,022
24426.3.204.0/2226.3.204.1 to 26.3.207.25426.3.207.2551,022
24526.3.208.0/2226.3.208.1 to 26.3.211.25426.3.211.2551,022
24626.3.212.0/2226.3.212.1 to 26.3.215.25426.3.215.2551,022
24726.3.216.0/2226.3.216.1 to 26.3.219.25426.3.219.2551,022
24826.3.220.0/2226.3.220.1 to 26.3.223.25426.3.223.2551,022
24926.3.224.0/2226.3.224.1 to 26.3.227.25426.3.227.2551,022
25026.3.228.0/2226.3.228.1 to 26.3.231.25426.3.231.2551,022
25126.3.232.0/2226.3.232.1 to 26.3.235.25426.3.235.2551,022
25226.3.236.0/2226.3.236.1 to 26.3.239.25426.3.239.2551,022
25326.3.240.0/2226.3.240.1 to 26.3.243.25426.3.243.2551,022
25426.3.244.0/2226.3.244.1 to 26.3.247.25426.3.247.2551,022
25526.3.248.0/2226.3.248.1 to 26.3.251.25426.3.251.2551,022
25626.3.252.0/2226.3.252.1 to 26.3.255.25426.3.255.2551,022

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.