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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.

Network58.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
58.0.0.0
Broadcast address
59.255.255.255
First usable
58.0.0.1
Last usable
59.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 3A000000 · Integer 973078528 to 1006632959
Reverse DNS zones
58.in-addr.arpa
59.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00111010.00000000.00000000.0000000058.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network00111010.00000000.00000000.0000000058.0.0.0
Broadcast00111011.11111111.11111111.1111111159.255.255.255
Split into smaller subnets/15
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

58.0.0.0/7 makes 256 subnets of /15.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
158.0.0.0/1558.0.0.1 to 58.1.255.25458.1.255.255131,070
258.2.0.0/1558.2.0.1 to 58.3.255.25458.3.255.255131,070
358.4.0.0/1558.4.0.1 to 58.5.255.25458.5.255.255131,070
458.6.0.0/1558.6.0.1 to 58.7.255.25458.7.255.255131,070
558.8.0.0/1558.8.0.1 to 58.9.255.25458.9.255.255131,070
658.10.0.0/1558.10.0.1 to 58.11.255.25458.11.255.255131,070
758.12.0.0/1558.12.0.1 to 58.13.255.25458.13.255.255131,070
858.14.0.0/1558.14.0.1 to 58.15.255.25458.15.255.255131,070
958.16.0.0/1558.16.0.1 to 58.17.255.25458.17.255.255131,070
1058.18.0.0/1558.18.0.1 to 58.19.255.25458.19.255.255131,070
1158.20.0.0/1558.20.0.1 to 58.21.255.25458.21.255.255131,070
1258.22.0.0/1558.22.0.1 to 58.23.255.25458.23.255.255131,070
1358.24.0.0/1558.24.0.1 to 58.25.255.25458.25.255.255131,070
1458.26.0.0/1558.26.0.1 to 58.27.255.25458.27.255.255131,070
1558.28.0.0/1558.28.0.1 to 58.29.255.25458.29.255.255131,070
1658.30.0.0/1558.30.0.1 to 58.31.255.25458.31.255.255131,070
1758.32.0.0/1558.32.0.1 to 58.33.255.25458.33.255.255131,070
1858.34.0.0/1558.34.0.1 to 58.35.255.25458.35.255.255131,070
1958.36.0.0/1558.36.0.1 to 58.37.255.25458.37.255.255131,070
2058.38.0.0/1558.38.0.1 to 58.39.255.25458.39.255.255131,070
2158.40.0.0/1558.40.0.1 to 58.41.255.25458.41.255.255131,070
2258.42.0.0/1558.42.0.1 to 58.43.255.25458.43.255.255131,070
2358.44.0.0/1558.44.0.1 to 58.45.255.25458.45.255.255131,070
2458.46.0.0/1558.46.0.1 to 58.47.255.25458.47.255.255131,070
2558.48.0.0/1558.48.0.1 to 58.49.255.25458.49.255.255131,070
2658.50.0.0/1558.50.0.1 to 58.51.255.25458.51.255.255131,070
2758.52.0.0/1558.52.0.1 to 58.53.255.25458.53.255.255131,070
2858.54.0.0/1558.54.0.1 to 58.55.255.25458.55.255.255131,070
2958.56.0.0/1558.56.0.1 to 58.57.255.25458.57.255.255131,070
3058.58.0.0/1558.58.0.1 to 58.59.255.25458.59.255.255131,070
3158.60.0.0/1558.60.0.1 to 58.61.255.25458.61.255.255131,070
3258.62.0.0/1558.62.0.1 to 58.63.255.25458.63.255.255131,070
3358.64.0.0/1558.64.0.1 to 58.65.255.25458.65.255.255131,070
3458.66.0.0/1558.66.0.1 to 58.67.255.25458.67.255.255131,070
3558.68.0.0/1558.68.0.1 to 58.69.255.25458.69.255.255131,070
3658.70.0.0/1558.70.0.1 to 58.71.255.25458.71.255.255131,070
3758.72.0.0/1558.72.0.1 to 58.73.255.25458.73.255.255131,070
3858.74.0.0/1558.74.0.1 to 58.75.255.25458.75.255.255131,070
3958.76.0.0/1558.76.0.1 to 58.77.255.25458.77.255.255131,070
4058.78.0.0/1558.78.0.1 to 58.79.255.25458.79.255.255131,070
4158.80.0.0/1558.80.0.1 to 58.81.255.25458.81.255.255131,070
4258.82.0.0/1558.82.0.1 to 58.83.255.25458.83.255.255131,070
4358.84.0.0/1558.84.0.1 to 58.85.255.25458.85.255.255131,070
4458.86.0.0/1558.86.0.1 to 58.87.255.25458.87.255.255131,070
4558.88.0.0/1558.88.0.1 to 58.89.255.25458.89.255.255131,070
4658.90.0.0/1558.90.0.1 to 58.91.255.25458.91.255.255131,070
4758.92.0.0/1558.92.0.1 to 58.93.255.25458.93.255.255131,070
4858.94.0.0/1558.94.0.1 to 58.95.255.25458.95.255.255131,070
4958.96.0.0/1558.96.0.1 to 58.97.255.25458.97.255.255131,070
5058.98.0.0/1558.98.0.1 to 58.99.255.25458.99.255.255131,070
5158.100.0.0/1558.100.0.1 to 58.101.255.25458.101.255.255131,070
5258.102.0.0/1558.102.0.1 to 58.103.255.25458.103.255.255131,070
5358.104.0.0/1558.104.0.1 to 58.105.255.25458.105.255.255131,070
5458.106.0.0/1558.106.0.1 to 58.107.255.25458.107.255.255131,070
5558.108.0.0/1558.108.0.1 to 58.109.255.25458.109.255.255131,070
5658.110.0.0/1558.110.0.1 to 58.111.255.25458.111.255.255131,070
5758.112.0.0/1558.112.0.1 to 58.113.255.25458.113.255.255131,070
5858.114.0.0/1558.114.0.1 to 58.115.255.25458.115.255.255131,070
5958.116.0.0/1558.116.0.1 to 58.117.255.25458.117.255.255131,070
6058.118.0.0/1558.118.0.1 to 58.119.255.25458.119.255.255131,070
6158.120.0.0/1558.120.0.1 to 58.121.255.25458.121.255.255131,070
6258.122.0.0/1558.122.0.1 to 58.123.255.25458.123.255.255131,070
6358.124.0.0/1558.124.0.1 to 58.125.255.25458.125.255.255131,070
6458.126.0.0/1558.126.0.1 to 58.127.255.25458.127.255.255131,070
6558.128.0.0/1558.128.0.1 to 58.129.255.25458.129.255.255131,070
6658.130.0.0/1558.130.0.1 to 58.131.255.25458.131.255.255131,070
6758.132.0.0/1558.132.0.1 to 58.133.255.25458.133.255.255131,070
6858.134.0.0/1558.134.0.1 to 58.135.255.25458.135.255.255131,070
6958.136.0.0/1558.136.0.1 to 58.137.255.25458.137.255.255131,070
7058.138.0.0/1558.138.0.1 to 58.139.255.25458.139.255.255131,070
7158.140.0.0/1558.140.0.1 to 58.141.255.25458.141.255.255131,070
7258.142.0.0/1558.142.0.1 to 58.143.255.25458.143.255.255131,070
7358.144.0.0/1558.144.0.1 to 58.145.255.25458.145.255.255131,070
7458.146.0.0/1558.146.0.1 to 58.147.255.25458.147.255.255131,070
7558.148.0.0/1558.148.0.1 to 58.149.255.25458.149.255.255131,070
7658.150.0.0/1558.150.0.1 to 58.151.255.25458.151.255.255131,070
7758.152.0.0/1558.152.0.1 to 58.153.255.25458.153.255.255131,070
7858.154.0.0/1558.154.0.1 to 58.155.255.25458.155.255.255131,070
7958.156.0.0/1558.156.0.1 to 58.157.255.25458.157.255.255131,070
8058.158.0.0/1558.158.0.1 to 58.159.255.25458.159.255.255131,070
8158.160.0.0/1558.160.0.1 to 58.161.255.25458.161.255.255131,070
8258.162.0.0/1558.162.0.1 to 58.163.255.25458.163.255.255131,070
8358.164.0.0/1558.164.0.1 to 58.165.255.25458.165.255.255131,070
8458.166.0.0/1558.166.0.1 to 58.167.255.25458.167.255.255131,070
8558.168.0.0/1558.168.0.1 to 58.169.255.25458.169.255.255131,070
8658.170.0.0/1558.170.0.1 to 58.171.255.25458.171.255.255131,070
8758.172.0.0/1558.172.0.1 to 58.173.255.25458.173.255.255131,070
8858.174.0.0/1558.174.0.1 to 58.175.255.25458.175.255.255131,070
8958.176.0.0/1558.176.0.1 to 58.177.255.25458.177.255.255131,070
9058.178.0.0/1558.178.0.1 to 58.179.255.25458.179.255.255131,070
9158.180.0.0/1558.180.0.1 to 58.181.255.25458.181.255.255131,070
9258.182.0.0/1558.182.0.1 to 58.183.255.25458.183.255.255131,070
9358.184.0.0/1558.184.0.1 to 58.185.255.25458.185.255.255131,070
9458.186.0.0/1558.186.0.1 to 58.187.255.25458.187.255.255131,070
9558.188.0.0/1558.188.0.1 to 58.189.255.25458.189.255.255131,070
9658.190.0.0/1558.190.0.1 to 58.191.255.25458.191.255.255131,070
9758.192.0.0/1558.192.0.1 to 58.193.255.25458.193.255.255131,070
9858.194.0.0/1558.194.0.1 to 58.195.255.25458.195.255.255131,070
9958.196.0.0/1558.196.0.1 to 58.197.255.25458.197.255.255131,070
10058.198.0.0/1558.198.0.1 to 58.199.255.25458.199.255.255131,070
10158.200.0.0/1558.200.0.1 to 58.201.255.25458.201.255.255131,070
10258.202.0.0/1558.202.0.1 to 58.203.255.25458.203.255.255131,070
10358.204.0.0/1558.204.0.1 to 58.205.255.25458.205.255.255131,070
10458.206.0.0/1558.206.0.1 to 58.207.255.25458.207.255.255131,070
10558.208.0.0/1558.208.0.1 to 58.209.255.25458.209.255.255131,070
10658.210.0.0/1558.210.0.1 to 58.211.255.25458.211.255.255131,070
10758.212.0.0/1558.212.0.1 to 58.213.255.25458.213.255.255131,070
10858.214.0.0/1558.214.0.1 to 58.215.255.25458.215.255.255131,070
10958.216.0.0/1558.216.0.1 to 58.217.255.25458.217.255.255131,070
11058.218.0.0/1558.218.0.1 to 58.219.255.25458.219.255.255131,070
11158.220.0.0/1558.220.0.1 to 58.221.255.25458.221.255.255131,070
11258.222.0.0/1558.222.0.1 to 58.223.255.25458.223.255.255131,070
11358.224.0.0/1558.224.0.1 to 58.225.255.25458.225.255.255131,070
11458.226.0.0/1558.226.0.1 to 58.227.255.25458.227.255.255131,070
11558.228.0.0/1558.228.0.1 to 58.229.255.25458.229.255.255131,070
11658.230.0.0/1558.230.0.1 to 58.231.255.25458.231.255.255131,070
11758.232.0.0/1558.232.0.1 to 58.233.255.25458.233.255.255131,070
11858.234.0.0/1558.234.0.1 to 58.235.255.25458.235.255.255131,070
11958.236.0.0/1558.236.0.1 to 58.237.255.25458.237.255.255131,070
12058.238.0.0/1558.238.0.1 to 58.239.255.25458.239.255.255131,070
12158.240.0.0/1558.240.0.1 to 58.241.255.25458.241.255.255131,070
12258.242.0.0/1558.242.0.1 to 58.243.255.25458.243.255.255131,070
12358.244.0.0/1558.244.0.1 to 58.245.255.25458.245.255.255131,070
12458.246.0.0/1558.246.0.1 to 58.247.255.25458.247.255.255131,070
12558.248.0.0/1558.248.0.1 to 58.249.255.25458.249.255.255131,070
12658.250.0.0/1558.250.0.1 to 58.251.255.25458.251.255.255131,070
12758.252.0.0/1558.252.0.1 to 58.253.255.25458.253.255.255131,070
12858.254.0.0/1558.254.0.1 to 58.255.255.25458.255.255.255131,070
12959.0.0.0/1559.0.0.1 to 59.1.255.25459.1.255.255131,070
13059.2.0.0/1559.2.0.1 to 59.3.255.25459.3.255.255131,070
13159.4.0.0/1559.4.0.1 to 59.5.255.25459.5.255.255131,070
13259.6.0.0/1559.6.0.1 to 59.7.255.25459.7.255.255131,070
13359.8.0.0/1559.8.0.1 to 59.9.255.25459.9.255.255131,070
13459.10.0.0/1559.10.0.1 to 59.11.255.25459.11.255.255131,070
13559.12.0.0/1559.12.0.1 to 59.13.255.25459.13.255.255131,070
13659.14.0.0/1559.14.0.1 to 59.15.255.25459.15.255.255131,070
13759.16.0.0/1559.16.0.1 to 59.17.255.25459.17.255.255131,070
13859.18.0.0/1559.18.0.1 to 59.19.255.25459.19.255.255131,070
13959.20.0.0/1559.20.0.1 to 59.21.255.25459.21.255.255131,070
14059.22.0.0/1559.22.0.1 to 59.23.255.25459.23.255.255131,070
14159.24.0.0/1559.24.0.1 to 59.25.255.25459.25.255.255131,070
14259.26.0.0/1559.26.0.1 to 59.27.255.25459.27.255.255131,070
14359.28.0.0/1559.28.0.1 to 59.29.255.25459.29.255.255131,070
14459.30.0.0/1559.30.0.1 to 59.31.255.25459.31.255.255131,070
14559.32.0.0/1559.32.0.1 to 59.33.255.25459.33.255.255131,070
14659.34.0.0/1559.34.0.1 to 59.35.255.25459.35.255.255131,070
14759.36.0.0/1559.36.0.1 to 59.37.255.25459.37.255.255131,070
14859.38.0.0/1559.38.0.1 to 59.39.255.25459.39.255.255131,070
14959.40.0.0/1559.40.0.1 to 59.41.255.25459.41.255.255131,070
15059.42.0.0/1559.42.0.1 to 59.43.255.25459.43.255.255131,070
15159.44.0.0/1559.44.0.1 to 59.45.255.25459.45.255.255131,070
15259.46.0.0/1559.46.0.1 to 59.47.255.25459.47.255.255131,070
15359.48.0.0/1559.48.0.1 to 59.49.255.25459.49.255.255131,070
15459.50.0.0/1559.50.0.1 to 59.51.255.25459.51.255.255131,070
15559.52.0.0/1559.52.0.1 to 59.53.255.25459.53.255.255131,070
15659.54.0.0/1559.54.0.1 to 59.55.255.25459.55.255.255131,070
15759.56.0.0/1559.56.0.1 to 59.57.255.25459.57.255.255131,070
15859.58.0.0/1559.58.0.1 to 59.59.255.25459.59.255.255131,070
15959.60.0.0/1559.60.0.1 to 59.61.255.25459.61.255.255131,070
16059.62.0.0/1559.62.0.1 to 59.63.255.25459.63.255.255131,070
16159.64.0.0/1559.64.0.1 to 59.65.255.25459.65.255.255131,070
16259.66.0.0/1559.66.0.1 to 59.67.255.25459.67.255.255131,070
16359.68.0.0/1559.68.0.1 to 59.69.255.25459.69.255.255131,070
16459.70.0.0/1559.70.0.1 to 59.71.255.25459.71.255.255131,070
16559.72.0.0/1559.72.0.1 to 59.73.255.25459.73.255.255131,070
16659.74.0.0/1559.74.0.1 to 59.75.255.25459.75.255.255131,070
16759.76.0.0/1559.76.0.1 to 59.77.255.25459.77.255.255131,070
16859.78.0.0/1559.78.0.1 to 59.79.255.25459.79.255.255131,070
16959.80.0.0/1559.80.0.1 to 59.81.255.25459.81.255.255131,070
17059.82.0.0/1559.82.0.1 to 59.83.255.25459.83.255.255131,070
17159.84.0.0/1559.84.0.1 to 59.85.255.25459.85.255.255131,070
17259.86.0.0/1559.86.0.1 to 59.87.255.25459.87.255.255131,070
17359.88.0.0/1559.88.0.1 to 59.89.255.25459.89.255.255131,070
17459.90.0.0/1559.90.0.1 to 59.91.255.25459.91.255.255131,070
17559.92.0.0/1559.92.0.1 to 59.93.255.25459.93.255.255131,070
17659.94.0.0/1559.94.0.1 to 59.95.255.25459.95.255.255131,070
17759.96.0.0/1559.96.0.1 to 59.97.255.25459.97.255.255131,070
17859.98.0.0/1559.98.0.1 to 59.99.255.25459.99.255.255131,070
17959.100.0.0/1559.100.0.1 to 59.101.255.25459.101.255.255131,070
18059.102.0.0/1559.102.0.1 to 59.103.255.25459.103.255.255131,070
18159.104.0.0/1559.104.0.1 to 59.105.255.25459.105.255.255131,070
18259.106.0.0/1559.106.0.1 to 59.107.255.25459.107.255.255131,070
18359.108.0.0/1559.108.0.1 to 59.109.255.25459.109.255.255131,070
18459.110.0.0/1559.110.0.1 to 59.111.255.25459.111.255.255131,070
18559.112.0.0/1559.112.0.1 to 59.113.255.25459.113.255.255131,070
18659.114.0.0/1559.114.0.1 to 59.115.255.25459.115.255.255131,070
18759.116.0.0/1559.116.0.1 to 59.117.255.25459.117.255.255131,070
18859.118.0.0/1559.118.0.1 to 59.119.255.25459.119.255.255131,070
18959.120.0.0/1559.120.0.1 to 59.121.255.25459.121.255.255131,070
19059.122.0.0/1559.122.0.1 to 59.123.255.25459.123.255.255131,070
19159.124.0.0/1559.124.0.1 to 59.125.255.25459.125.255.255131,070
19259.126.0.0/1559.126.0.1 to 59.127.255.25459.127.255.255131,070
19359.128.0.0/1559.128.0.1 to 59.129.255.25459.129.255.255131,070
19459.130.0.0/1559.130.0.1 to 59.131.255.25459.131.255.255131,070
19559.132.0.0/1559.132.0.1 to 59.133.255.25459.133.255.255131,070
19659.134.0.0/1559.134.0.1 to 59.135.255.25459.135.255.255131,070
19759.136.0.0/1559.136.0.1 to 59.137.255.25459.137.255.255131,070
19859.138.0.0/1559.138.0.1 to 59.139.255.25459.139.255.255131,070
19959.140.0.0/1559.140.0.1 to 59.141.255.25459.141.255.255131,070
20059.142.0.0/1559.142.0.1 to 59.143.255.25459.143.255.255131,070
20159.144.0.0/1559.144.0.1 to 59.145.255.25459.145.255.255131,070
20259.146.0.0/1559.146.0.1 to 59.147.255.25459.147.255.255131,070
20359.148.0.0/1559.148.0.1 to 59.149.255.25459.149.255.255131,070
20459.150.0.0/1559.150.0.1 to 59.151.255.25459.151.255.255131,070
20559.152.0.0/1559.152.0.1 to 59.153.255.25459.153.255.255131,070
20659.154.0.0/1559.154.0.1 to 59.155.255.25459.155.255.255131,070
20759.156.0.0/1559.156.0.1 to 59.157.255.25459.157.255.255131,070
20859.158.0.0/1559.158.0.1 to 59.159.255.25459.159.255.255131,070
20959.160.0.0/1559.160.0.1 to 59.161.255.25459.161.255.255131,070
21059.162.0.0/1559.162.0.1 to 59.163.255.25459.163.255.255131,070
21159.164.0.0/1559.164.0.1 to 59.165.255.25459.165.255.255131,070
21259.166.0.0/1559.166.0.1 to 59.167.255.25459.167.255.255131,070
21359.168.0.0/1559.168.0.1 to 59.169.255.25459.169.255.255131,070
21459.170.0.0/1559.170.0.1 to 59.171.255.25459.171.255.255131,070
21559.172.0.0/1559.172.0.1 to 59.173.255.25459.173.255.255131,070
21659.174.0.0/1559.174.0.1 to 59.175.255.25459.175.255.255131,070
21759.176.0.0/1559.176.0.1 to 59.177.255.25459.177.255.255131,070
21859.178.0.0/1559.178.0.1 to 59.179.255.25459.179.255.255131,070
21959.180.0.0/1559.180.0.1 to 59.181.255.25459.181.255.255131,070
22059.182.0.0/1559.182.0.1 to 59.183.255.25459.183.255.255131,070
22159.184.0.0/1559.184.0.1 to 59.185.255.25459.185.255.255131,070
22259.186.0.0/1559.186.0.1 to 59.187.255.25459.187.255.255131,070
22359.188.0.0/1559.188.0.1 to 59.189.255.25459.189.255.255131,070
22459.190.0.0/1559.190.0.1 to 59.191.255.25459.191.255.255131,070
22559.192.0.0/1559.192.0.1 to 59.193.255.25459.193.255.255131,070
22659.194.0.0/1559.194.0.1 to 59.195.255.25459.195.255.255131,070
22759.196.0.0/1559.196.0.1 to 59.197.255.25459.197.255.255131,070
22859.198.0.0/1559.198.0.1 to 59.199.255.25459.199.255.255131,070
22959.200.0.0/1559.200.0.1 to 59.201.255.25459.201.255.255131,070
23059.202.0.0/1559.202.0.1 to 59.203.255.25459.203.255.255131,070
23159.204.0.0/1559.204.0.1 to 59.205.255.25459.205.255.255131,070
23259.206.0.0/1559.206.0.1 to 59.207.255.25459.207.255.255131,070
23359.208.0.0/1559.208.0.1 to 59.209.255.25459.209.255.255131,070
23459.210.0.0/1559.210.0.1 to 59.211.255.25459.211.255.255131,070
23559.212.0.0/1559.212.0.1 to 59.213.255.25459.213.255.255131,070
23659.214.0.0/1559.214.0.1 to 59.215.255.25459.215.255.255131,070
23759.216.0.0/1559.216.0.1 to 59.217.255.25459.217.255.255131,070
23859.218.0.0/1559.218.0.1 to 59.219.255.25459.219.255.255131,070
23959.220.0.0/1559.220.0.1 to 59.221.255.25459.221.255.255131,070
24059.222.0.0/1559.222.0.1 to 59.223.255.25459.223.255.255131,070
24159.224.0.0/1559.224.0.1 to 59.225.255.25459.225.255.255131,070
24259.226.0.0/1559.226.0.1 to 59.227.255.25459.227.255.255131,070
24359.228.0.0/1559.228.0.1 to 59.229.255.25459.229.255.255131,070
24459.230.0.0/1559.230.0.1 to 59.231.255.25459.231.255.255131,070
24559.232.0.0/1559.232.0.1 to 59.233.255.25459.233.255.255131,070
24659.234.0.0/1559.234.0.1 to 59.235.255.25459.235.255.255131,070
24759.236.0.0/1559.236.0.1 to 59.237.255.25459.237.255.255131,070
24859.238.0.0/1559.238.0.1 to 59.239.255.25459.239.255.255131,070
24959.240.0.0/1559.240.0.1 to 59.241.255.25459.241.255.255131,070
25059.242.0.0/1559.242.0.1 to 59.243.255.25459.243.255.255131,070
25159.244.0.0/1559.244.0.1 to 59.245.255.25459.245.255.255131,070
25259.246.0.0/1559.246.0.1 to 59.247.255.25459.247.255.255131,070
25359.248.0.0/1559.248.0.1 to 59.249.255.25459.249.255.255131,070
25459.250.0.0/1559.250.0.1 to 59.251.255.25459.251.255.255131,070
25559.252.0.0/1559.252.0.1 to 59.253.255.25459.253.255.255131,070
25659.254.0.0/1559.254.0.1 to 59.255.255.25459.255.255.255131,070

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.