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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.

Network97.84.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
97.84.0.0
Broadcast address
97.87.255.255
First usable
97.84.0.1
Last usable
97.87.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 61540000 · Integer 1632894976 to 1633157119
Reverse DNS zones
84.97.in-addr.arpa
85.97.in-addr.arpa
86.97.in-addr.arpa
87.97.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100001.01010100.00000000.0000000097.84.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01100001.01010100.00000000.0000000097.84.0.0
Broadcast01100001.01010111.11111111.1111111197.87.255.255
Split into smaller subnets/23
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

97.84.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
197.84.0.0/2397.84.0.1 to 97.84.1.25497.84.1.255510
297.84.2.0/2397.84.2.1 to 97.84.3.25497.84.3.255510
397.84.4.0/2397.84.4.1 to 97.84.5.25497.84.5.255510
497.84.6.0/2397.84.6.1 to 97.84.7.25497.84.7.255510
597.84.8.0/2397.84.8.1 to 97.84.9.25497.84.9.255510
697.84.10.0/2397.84.10.1 to 97.84.11.25497.84.11.255510
797.84.12.0/2397.84.12.1 to 97.84.13.25497.84.13.255510
897.84.14.0/2397.84.14.1 to 97.84.15.25497.84.15.255510
997.84.16.0/2397.84.16.1 to 97.84.17.25497.84.17.255510
1097.84.18.0/2397.84.18.1 to 97.84.19.25497.84.19.255510
1197.84.20.0/2397.84.20.1 to 97.84.21.25497.84.21.255510
1297.84.22.0/2397.84.22.1 to 97.84.23.25497.84.23.255510
1397.84.24.0/2397.84.24.1 to 97.84.25.25497.84.25.255510
1497.84.26.0/2397.84.26.1 to 97.84.27.25497.84.27.255510
1597.84.28.0/2397.84.28.1 to 97.84.29.25497.84.29.255510
1697.84.30.0/2397.84.30.1 to 97.84.31.25497.84.31.255510
1797.84.32.0/2397.84.32.1 to 97.84.33.25497.84.33.255510
1897.84.34.0/2397.84.34.1 to 97.84.35.25497.84.35.255510
1997.84.36.0/2397.84.36.1 to 97.84.37.25497.84.37.255510
2097.84.38.0/2397.84.38.1 to 97.84.39.25497.84.39.255510
2197.84.40.0/2397.84.40.1 to 97.84.41.25497.84.41.255510
2297.84.42.0/2397.84.42.1 to 97.84.43.25497.84.43.255510
2397.84.44.0/2397.84.44.1 to 97.84.45.25497.84.45.255510
2497.84.46.0/2397.84.46.1 to 97.84.47.25497.84.47.255510
2597.84.48.0/2397.84.48.1 to 97.84.49.25497.84.49.255510
2697.84.50.0/2397.84.50.1 to 97.84.51.25497.84.51.255510
2797.84.52.0/2397.84.52.1 to 97.84.53.25497.84.53.255510
2897.84.54.0/2397.84.54.1 to 97.84.55.25497.84.55.255510
2997.84.56.0/2397.84.56.1 to 97.84.57.25497.84.57.255510
3097.84.58.0/2397.84.58.1 to 97.84.59.25497.84.59.255510
3197.84.60.0/2397.84.60.1 to 97.84.61.25497.84.61.255510
3297.84.62.0/2397.84.62.1 to 97.84.63.25497.84.63.255510
3397.84.64.0/2397.84.64.1 to 97.84.65.25497.84.65.255510
3497.84.66.0/2397.84.66.1 to 97.84.67.25497.84.67.255510
3597.84.68.0/2397.84.68.1 to 97.84.69.25497.84.69.255510
3697.84.70.0/2397.84.70.1 to 97.84.71.25497.84.71.255510
3797.84.72.0/2397.84.72.1 to 97.84.73.25497.84.73.255510
3897.84.74.0/2397.84.74.1 to 97.84.75.25497.84.75.255510
3997.84.76.0/2397.84.76.1 to 97.84.77.25497.84.77.255510
4097.84.78.0/2397.84.78.1 to 97.84.79.25497.84.79.255510
4197.84.80.0/2397.84.80.1 to 97.84.81.25497.84.81.255510
4297.84.82.0/2397.84.82.1 to 97.84.83.25497.84.83.255510
4397.84.84.0/2397.84.84.1 to 97.84.85.25497.84.85.255510
4497.84.86.0/2397.84.86.1 to 97.84.87.25497.84.87.255510
4597.84.88.0/2397.84.88.1 to 97.84.89.25497.84.89.255510
4697.84.90.0/2397.84.90.1 to 97.84.91.25497.84.91.255510
4797.84.92.0/2397.84.92.1 to 97.84.93.25497.84.93.255510
4897.84.94.0/2397.84.94.1 to 97.84.95.25497.84.95.255510
4997.84.96.0/2397.84.96.1 to 97.84.97.25497.84.97.255510
5097.84.98.0/2397.84.98.1 to 97.84.99.25497.84.99.255510
5197.84.100.0/2397.84.100.1 to 97.84.101.25497.84.101.255510
5297.84.102.0/2397.84.102.1 to 97.84.103.25497.84.103.255510
5397.84.104.0/2397.84.104.1 to 97.84.105.25497.84.105.255510
5497.84.106.0/2397.84.106.1 to 97.84.107.25497.84.107.255510
5597.84.108.0/2397.84.108.1 to 97.84.109.25497.84.109.255510
5697.84.110.0/2397.84.110.1 to 97.84.111.25497.84.111.255510
5797.84.112.0/2397.84.112.1 to 97.84.113.25497.84.113.255510
5897.84.114.0/2397.84.114.1 to 97.84.115.25497.84.115.255510
5997.84.116.0/2397.84.116.1 to 97.84.117.25497.84.117.255510
6097.84.118.0/2397.84.118.1 to 97.84.119.25497.84.119.255510
6197.84.120.0/2397.84.120.1 to 97.84.121.25497.84.121.255510
6297.84.122.0/2397.84.122.1 to 97.84.123.25497.84.123.255510
6397.84.124.0/2397.84.124.1 to 97.84.125.25497.84.125.255510
6497.84.126.0/2397.84.126.1 to 97.84.127.25497.84.127.255510
6597.84.128.0/2397.84.128.1 to 97.84.129.25497.84.129.255510
6697.84.130.0/2397.84.130.1 to 97.84.131.25497.84.131.255510
6797.84.132.0/2397.84.132.1 to 97.84.133.25497.84.133.255510
6897.84.134.0/2397.84.134.1 to 97.84.135.25497.84.135.255510
6997.84.136.0/2397.84.136.1 to 97.84.137.25497.84.137.255510
7097.84.138.0/2397.84.138.1 to 97.84.139.25497.84.139.255510
7197.84.140.0/2397.84.140.1 to 97.84.141.25497.84.141.255510
7297.84.142.0/2397.84.142.1 to 97.84.143.25497.84.143.255510
7397.84.144.0/2397.84.144.1 to 97.84.145.25497.84.145.255510
7497.84.146.0/2397.84.146.1 to 97.84.147.25497.84.147.255510
7597.84.148.0/2397.84.148.1 to 97.84.149.25497.84.149.255510
7697.84.150.0/2397.84.150.1 to 97.84.151.25497.84.151.255510
7797.84.152.0/2397.84.152.1 to 97.84.153.25497.84.153.255510
7897.84.154.0/2397.84.154.1 to 97.84.155.25497.84.155.255510
7997.84.156.0/2397.84.156.1 to 97.84.157.25497.84.157.255510
8097.84.158.0/2397.84.158.1 to 97.84.159.25497.84.159.255510
8197.84.160.0/2397.84.160.1 to 97.84.161.25497.84.161.255510
8297.84.162.0/2397.84.162.1 to 97.84.163.25497.84.163.255510
8397.84.164.0/2397.84.164.1 to 97.84.165.25497.84.165.255510
8497.84.166.0/2397.84.166.1 to 97.84.167.25497.84.167.255510
8597.84.168.0/2397.84.168.1 to 97.84.169.25497.84.169.255510
8697.84.170.0/2397.84.170.1 to 97.84.171.25497.84.171.255510
8797.84.172.0/2397.84.172.1 to 97.84.173.25497.84.173.255510
8897.84.174.0/2397.84.174.1 to 97.84.175.25497.84.175.255510
8997.84.176.0/2397.84.176.1 to 97.84.177.25497.84.177.255510
9097.84.178.0/2397.84.178.1 to 97.84.179.25497.84.179.255510
9197.84.180.0/2397.84.180.1 to 97.84.181.25497.84.181.255510
9297.84.182.0/2397.84.182.1 to 97.84.183.25497.84.183.255510
9397.84.184.0/2397.84.184.1 to 97.84.185.25497.84.185.255510
9497.84.186.0/2397.84.186.1 to 97.84.187.25497.84.187.255510
9597.84.188.0/2397.84.188.1 to 97.84.189.25497.84.189.255510
9697.84.190.0/2397.84.190.1 to 97.84.191.25497.84.191.255510
9797.84.192.0/2397.84.192.1 to 97.84.193.25497.84.193.255510
9897.84.194.0/2397.84.194.1 to 97.84.195.25497.84.195.255510
9997.84.196.0/2397.84.196.1 to 97.84.197.25497.84.197.255510
10097.84.198.0/2397.84.198.1 to 97.84.199.25497.84.199.255510
10197.84.200.0/2397.84.200.1 to 97.84.201.25497.84.201.255510
10297.84.202.0/2397.84.202.1 to 97.84.203.25497.84.203.255510
10397.84.204.0/2397.84.204.1 to 97.84.205.25497.84.205.255510
10497.84.206.0/2397.84.206.1 to 97.84.207.25497.84.207.255510
10597.84.208.0/2397.84.208.1 to 97.84.209.25497.84.209.255510
10697.84.210.0/2397.84.210.1 to 97.84.211.25497.84.211.255510
10797.84.212.0/2397.84.212.1 to 97.84.213.25497.84.213.255510
10897.84.214.0/2397.84.214.1 to 97.84.215.25497.84.215.255510
10997.84.216.0/2397.84.216.1 to 97.84.217.25497.84.217.255510
11097.84.218.0/2397.84.218.1 to 97.84.219.25497.84.219.255510
11197.84.220.0/2397.84.220.1 to 97.84.221.25497.84.221.255510
11297.84.222.0/2397.84.222.1 to 97.84.223.25497.84.223.255510
11397.84.224.0/2397.84.224.1 to 97.84.225.25497.84.225.255510
11497.84.226.0/2397.84.226.1 to 97.84.227.25497.84.227.255510
11597.84.228.0/2397.84.228.1 to 97.84.229.25497.84.229.255510
11697.84.230.0/2397.84.230.1 to 97.84.231.25497.84.231.255510
11797.84.232.0/2397.84.232.1 to 97.84.233.25497.84.233.255510
11897.84.234.0/2397.84.234.1 to 97.84.235.25497.84.235.255510
11997.84.236.0/2397.84.236.1 to 97.84.237.25497.84.237.255510
12097.84.238.0/2397.84.238.1 to 97.84.239.25497.84.239.255510
12197.84.240.0/2397.84.240.1 to 97.84.241.25497.84.241.255510
12297.84.242.0/2397.84.242.1 to 97.84.243.25497.84.243.255510
12397.84.244.0/2397.84.244.1 to 97.84.245.25497.84.245.255510
12497.84.246.0/2397.84.246.1 to 97.84.247.25497.84.247.255510
12597.84.248.0/2397.84.248.1 to 97.84.249.25497.84.249.255510
12697.84.250.0/2397.84.250.1 to 97.84.251.25497.84.251.255510
12797.84.252.0/2397.84.252.1 to 97.84.253.25497.84.253.255510
12897.84.254.0/2397.84.254.1 to 97.84.255.25497.84.255.255510
12997.85.0.0/2397.85.0.1 to 97.85.1.25497.85.1.255510
13097.85.2.0/2397.85.2.1 to 97.85.3.25497.85.3.255510
13197.85.4.0/2397.85.4.1 to 97.85.5.25497.85.5.255510
13297.85.6.0/2397.85.6.1 to 97.85.7.25497.85.7.255510
13397.85.8.0/2397.85.8.1 to 97.85.9.25497.85.9.255510
13497.85.10.0/2397.85.10.1 to 97.85.11.25497.85.11.255510
13597.85.12.0/2397.85.12.1 to 97.85.13.25497.85.13.255510
13697.85.14.0/2397.85.14.1 to 97.85.15.25497.85.15.255510
13797.85.16.0/2397.85.16.1 to 97.85.17.25497.85.17.255510
13897.85.18.0/2397.85.18.1 to 97.85.19.25497.85.19.255510
13997.85.20.0/2397.85.20.1 to 97.85.21.25497.85.21.255510
14097.85.22.0/2397.85.22.1 to 97.85.23.25497.85.23.255510
14197.85.24.0/2397.85.24.1 to 97.85.25.25497.85.25.255510
14297.85.26.0/2397.85.26.1 to 97.85.27.25497.85.27.255510
14397.85.28.0/2397.85.28.1 to 97.85.29.25497.85.29.255510
14497.85.30.0/2397.85.30.1 to 97.85.31.25497.85.31.255510
14597.85.32.0/2397.85.32.1 to 97.85.33.25497.85.33.255510
14697.85.34.0/2397.85.34.1 to 97.85.35.25497.85.35.255510
14797.85.36.0/2397.85.36.1 to 97.85.37.25497.85.37.255510
14897.85.38.0/2397.85.38.1 to 97.85.39.25497.85.39.255510
14997.85.40.0/2397.85.40.1 to 97.85.41.25497.85.41.255510
15097.85.42.0/2397.85.42.1 to 97.85.43.25497.85.43.255510
15197.85.44.0/2397.85.44.1 to 97.85.45.25497.85.45.255510
15297.85.46.0/2397.85.46.1 to 97.85.47.25497.85.47.255510
15397.85.48.0/2397.85.48.1 to 97.85.49.25497.85.49.255510
15497.85.50.0/2397.85.50.1 to 97.85.51.25497.85.51.255510
15597.85.52.0/2397.85.52.1 to 97.85.53.25497.85.53.255510
15697.85.54.0/2397.85.54.1 to 97.85.55.25497.85.55.255510
15797.85.56.0/2397.85.56.1 to 97.85.57.25497.85.57.255510
15897.85.58.0/2397.85.58.1 to 97.85.59.25497.85.59.255510
15997.85.60.0/2397.85.60.1 to 97.85.61.25497.85.61.255510
16097.85.62.0/2397.85.62.1 to 97.85.63.25497.85.63.255510
16197.85.64.0/2397.85.64.1 to 97.85.65.25497.85.65.255510
16297.85.66.0/2397.85.66.1 to 97.85.67.25497.85.67.255510
16397.85.68.0/2397.85.68.1 to 97.85.69.25497.85.69.255510
16497.85.70.0/2397.85.70.1 to 97.85.71.25497.85.71.255510
16597.85.72.0/2397.85.72.1 to 97.85.73.25497.85.73.255510
16697.85.74.0/2397.85.74.1 to 97.85.75.25497.85.75.255510
16797.85.76.0/2397.85.76.1 to 97.85.77.25497.85.77.255510
16897.85.78.0/2397.85.78.1 to 97.85.79.25497.85.79.255510
16997.85.80.0/2397.85.80.1 to 97.85.81.25497.85.81.255510
17097.85.82.0/2397.85.82.1 to 97.85.83.25497.85.83.255510
17197.85.84.0/2397.85.84.1 to 97.85.85.25497.85.85.255510
17297.85.86.0/2397.85.86.1 to 97.85.87.25497.85.87.255510
17397.85.88.0/2397.85.88.1 to 97.85.89.25497.85.89.255510
17497.85.90.0/2397.85.90.1 to 97.85.91.25497.85.91.255510
17597.85.92.0/2397.85.92.1 to 97.85.93.25497.85.93.255510
17697.85.94.0/2397.85.94.1 to 97.85.95.25497.85.95.255510
17797.85.96.0/2397.85.96.1 to 97.85.97.25497.85.97.255510
17897.85.98.0/2397.85.98.1 to 97.85.99.25497.85.99.255510
17997.85.100.0/2397.85.100.1 to 97.85.101.25497.85.101.255510
18097.85.102.0/2397.85.102.1 to 97.85.103.25497.85.103.255510
18197.85.104.0/2397.85.104.1 to 97.85.105.25497.85.105.255510
18297.85.106.0/2397.85.106.1 to 97.85.107.25497.85.107.255510
18397.85.108.0/2397.85.108.1 to 97.85.109.25497.85.109.255510
18497.85.110.0/2397.85.110.1 to 97.85.111.25497.85.111.255510
18597.85.112.0/2397.85.112.1 to 97.85.113.25497.85.113.255510
18697.85.114.0/2397.85.114.1 to 97.85.115.25497.85.115.255510
18797.85.116.0/2397.85.116.1 to 97.85.117.25497.85.117.255510
18897.85.118.0/2397.85.118.1 to 97.85.119.25497.85.119.255510
18997.85.120.0/2397.85.120.1 to 97.85.121.25497.85.121.255510
19097.85.122.0/2397.85.122.1 to 97.85.123.25497.85.123.255510
19197.85.124.0/2397.85.124.1 to 97.85.125.25497.85.125.255510
19297.85.126.0/2397.85.126.1 to 97.85.127.25497.85.127.255510
19397.85.128.0/2397.85.128.1 to 97.85.129.25497.85.129.255510
19497.85.130.0/2397.85.130.1 to 97.85.131.25497.85.131.255510
19597.85.132.0/2397.85.132.1 to 97.85.133.25497.85.133.255510
19697.85.134.0/2397.85.134.1 to 97.85.135.25497.85.135.255510
19797.85.136.0/2397.85.136.1 to 97.85.137.25497.85.137.255510
19897.85.138.0/2397.85.138.1 to 97.85.139.25497.85.139.255510
19997.85.140.0/2397.85.140.1 to 97.85.141.25497.85.141.255510
20097.85.142.0/2397.85.142.1 to 97.85.143.25497.85.143.255510
20197.85.144.0/2397.85.144.1 to 97.85.145.25497.85.145.255510
20297.85.146.0/2397.85.146.1 to 97.85.147.25497.85.147.255510
20397.85.148.0/2397.85.148.1 to 97.85.149.25497.85.149.255510
20497.85.150.0/2397.85.150.1 to 97.85.151.25497.85.151.255510
20597.85.152.0/2397.85.152.1 to 97.85.153.25497.85.153.255510
20697.85.154.0/2397.85.154.1 to 97.85.155.25497.85.155.255510
20797.85.156.0/2397.85.156.1 to 97.85.157.25497.85.157.255510
20897.85.158.0/2397.85.158.1 to 97.85.159.25497.85.159.255510
20997.85.160.0/2397.85.160.1 to 97.85.161.25497.85.161.255510
21097.85.162.0/2397.85.162.1 to 97.85.163.25497.85.163.255510
21197.85.164.0/2397.85.164.1 to 97.85.165.25497.85.165.255510
21297.85.166.0/2397.85.166.1 to 97.85.167.25497.85.167.255510
21397.85.168.0/2397.85.168.1 to 97.85.169.25497.85.169.255510
21497.85.170.0/2397.85.170.1 to 97.85.171.25497.85.171.255510
21597.85.172.0/2397.85.172.1 to 97.85.173.25497.85.173.255510
21697.85.174.0/2397.85.174.1 to 97.85.175.25497.85.175.255510
21797.85.176.0/2397.85.176.1 to 97.85.177.25497.85.177.255510
21897.85.178.0/2397.85.178.1 to 97.85.179.25497.85.179.255510
21997.85.180.0/2397.85.180.1 to 97.85.181.25497.85.181.255510
22097.85.182.0/2397.85.182.1 to 97.85.183.25497.85.183.255510
22197.85.184.0/2397.85.184.1 to 97.85.185.25497.85.185.255510
22297.85.186.0/2397.85.186.1 to 97.85.187.25497.85.187.255510
22397.85.188.0/2397.85.188.1 to 97.85.189.25497.85.189.255510
22497.85.190.0/2397.85.190.1 to 97.85.191.25497.85.191.255510
22597.85.192.0/2397.85.192.1 to 97.85.193.25497.85.193.255510
22697.85.194.0/2397.85.194.1 to 97.85.195.25497.85.195.255510
22797.85.196.0/2397.85.196.1 to 97.85.197.25497.85.197.255510
22897.85.198.0/2397.85.198.1 to 97.85.199.25497.85.199.255510
22997.85.200.0/2397.85.200.1 to 97.85.201.25497.85.201.255510
23097.85.202.0/2397.85.202.1 to 97.85.203.25497.85.203.255510
23197.85.204.0/2397.85.204.1 to 97.85.205.25497.85.205.255510
23297.85.206.0/2397.85.206.1 to 97.85.207.25497.85.207.255510
23397.85.208.0/2397.85.208.1 to 97.85.209.25497.85.209.255510
23497.85.210.0/2397.85.210.1 to 97.85.211.25497.85.211.255510
23597.85.212.0/2397.85.212.1 to 97.85.213.25497.85.213.255510
23697.85.214.0/2397.85.214.1 to 97.85.215.25497.85.215.255510
23797.85.216.0/2397.85.216.1 to 97.85.217.25497.85.217.255510
23897.85.218.0/2397.85.218.1 to 97.85.219.25497.85.219.255510
23997.85.220.0/2397.85.220.1 to 97.85.221.25497.85.221.255510
24097.85.222.0/2397.85.222.1 to 97.85.223.25497.85.223.255510
24197.85.224.0/2397.85.224.1 to 97.85.225.25497.85.225.255510
24297.85.226.0/2397.85.226.1 to 97.85.227.25497.85.227.255510
24397.85.228.0/2397.85.228.1 to 97.85.229.25497.85.229.255510
24497.85.230.0/2397.85.230.1 to 97.85.231.25497.85.231.255510
24597.85.232.0/2397.85.232.1 to 97.85.233.25497.85.233.255510
24697.85.234.0/2397.85.234.1 to 97.85.235.25497.85.235.255510
24797.85.236.0/2397.85.236.1 to 97.85.237.25497.85.237.255510
24897.85.238.0/2397.85.238.1 to 97.85.239.25497.85.239.255510
24997.85.240.0/2397.85.240.1 to 97.85.241.25497.85.241.255510
25097.85.242.0/2397.85.242.1 to 97.85.243.25497.85.243.255510
25197.85.244.0/2397.85.244.1 to 97.85.245.25497.85.245.255510
25297.85.246.0/2397.85.246.1 to 97.85.247.25497.85.247.255510
25397.85.248.0/2397.85.248.1 to 97.85.249.25497.85.249.255510
25497.85.250.0/2397.85.250.1 to 97.85.251.25497.85.251.255510
25597.85.252.0/2397.85.252.1 to 97.85.253.25497.85.253.255510
25697.85.254.0/2397.85.254.1 to 97.85.255.25497.85.255.255510

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.