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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.

Network60.0.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
60.0.0.0
Broadcast address
60.7.255.255
First usable
60.0.0.1
Last usable
60.7.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 3C000000 · Integer 1006632960 to 1007157247
Reverse DNS zones
0.60.in-addr.arpa
1.60.in-addr.arpa
2.60.in-addr.arpa
3.60.in-addr.arpa
4.60.in-addr.arpa
5.60.in-addr.arpa
6.60.in-addr.arpa
7.60.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00111100.00000000.00000000.0000000060.0.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network00111100.00000000.00000000.0000000060.0.0.0
Broadcast00111100.00000111.11111111.1111111160.7.255.255
Split into smaller subnets/23
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

60.0.0.0/13 makes 1,024 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
160.0.0.0/2360.0.0.1 to 60.0.1.25460.0.1.255510
260.0.2.0/2360.0.2.1 to 60.0.3.25460.0.3.255510
360.0.4.0/2360.0.4.1 to 60.0.5.25460.0.5.255510
460.0.6.0/2360.0.6.1 to 60.0.7.25460.0.7.255510
560.0.8.0/2360.0.8.1 to 60.0.9.25460.0.9.255510
660.0.10.0/2360.0.10.1 to 60.0.11.25460.0.11.255510
760.0.12.0/2360.0.12.1 to 60.0.13.25460.0.13.255510
860.0.14.0/2360.0.14.1 to 60.0.15.25460.0.15.255510
960.0.16.0/2360.0.16.1 to 60.0.17.25460.0.17.255510
1060.0.18.0/2360.0.18.1 to 60.0.19.25460.0.19.255510
1160.0.20.0/2360.0.20.1 to 60.0.21.25460.0.21.255510
1260.0.22.0/2360.0.22.1 to 60.0.23.25460.0.23.255510
1360.0.24.0/2360.0.24.1 to 60.0.25.25460.0.25.255510
1460.0.26.0/2360.0.26.1 to 60.0.27.25460.0.27.255510
1560.0.28.0/2360.0.28.1 to 60.0.29.25460.0.29.255510
1660.0.30.0/2360.0.30.1 to 60.0.31.25460.0.31.255510
1760.0.32.0/2360.0.32.1 to 60.0.33.25460.0.33.255510
1860.0.34.0/2360.0.34.1 to 60.0.35.25460.0.35.255510
1960.0.36.0/2360.0.36.1 to 60.0.37.25460.0.37.255510
2060.0.38.0/2360.0.38.1 to 60.0.39.25460.0.39.255510
2160.0.40.0/2360.0.40.1 to 60.0.41.25460.0.41.255510
2260.0.42.0/2360.0.42.1 to 60.0.43.25460.0.43.255510
2360.0.44.0/2360.0.44.1 to 60.0.45.25460.0.45.255510
2460.0.46.0/2360.0.46.1 to 60.0.47.25460.0.47.255510
2560.0.48.0/2360.0.48.1 to 60.0.49.25460.0.49.255510
2660.0.50.0/2360.0.50.1 to 60.0.51.25460.0.51.255510
2760.0.52.0/2360.0.52.1 to 60.0.53.25460.0.53.255510
2860.0.54.0/2360.0.54.1 to 60.0.55.25460.0.55.255510
2960.0.56.0/2360.0.56.1 to 60.0.57.25460.0.57.255510
3060.0.58.0/2360.0.58.1 to 60.0.59.25460.0.59.255510
3160.0.60.0/2360.0.60.1 to 60.0.61.25460.0.61.255510
3260.0.62.0/2360.0.62.1 to 60.0.63.25460.0.63.255510
3360.0.64.0/2360.0.64.1 to 60.0.65.25460.0.65.255510
3460.0.66.0/2360.0.66.1 to 60.0.67.25460.0.67.255510
3560.0.68.0/2360.0.68.1 to 60.0.69.25460.0.69.255510
3660.0.70.0/2360.0.70.1 to 60.0.71.25460.0.71.255510
3760.0.72.0/2360.0.72.1 to 60.0.73.25460.0.73.255510
3860.0.74.0/2360.0.74.1 to 60.0.75.25460.0.75.255510
3960.0.76.0/2360.0.76.1 to 60.0.77.25460.0.77.255510
4060.0.78.0/2360.0.78.1 to 60.0.79.25460.0.79.255510
4160.0.80.0/2360.0.80.1 to 60.0.81.25460.0.81.255510
4260.0.82.0/2360.0.82.1 to 60.0.83.25460.0.83.255510
4360.0.84.0/2360.0.84.1 to 60.0.85.25460.0.85.255510
4460.0.86.0/2360.0.86.1 to 60.0.87.25460.0.87.255510
4560.0.88.0/2360.0.88.1 to 60.0.89.25460.0.89.255510
4660.0.90.0/2360.0.90.1 to 60.0.91.25460.0.91.255510
4760.0.92.0/2360.0.92.1 to 60.0.93.25460.0.93.255510
4860.0.94.0/2360.0.94.1 to 60.0.95.25460.0.95.255510
4960.0.96.0/2360.0.96.1 to 60.0.97.25460.0.97.255510
5060.0.98.0/2360.0.98.1 to 60.0.99.25460.0.99.255510
5160.0.100.0/2360.0.100.1 to 60.0.101.25460.0.101.255510
5260.0.102.0/2360.0.102.1 to 60.0.103.25460.0.103.255510
5360.0.104.0/2360.0.104.1 to 60.0.105.25460.0.105.255510
5460.0.106.0/2360.0.106.1 to 60.0.107.25460.0.107.255510
5560.0.108.0/2360.0.108.1 to 60.0.109.25460.0.109.255510
5660.0.110.0/2360.0.110.1 to 60.0.111.25460.0.111.255510
5760.0.112.0/2360.0.112.1 to 60.0.113.25460.0.113.255510
5860.0.114.0/2360.0.114.1 to 60.0.115.25460.0.115.255510
5960.0.116.0/2360.0.116.1 to 60.0.117.25460.0.117.255510
6060.0.118.0/2360.0.118.1 to 60.0.119.25460.0.119.255510
6160.0.120.0/2360.0.120.1 to 60.0.121.25460.0.121.255510
6260.0.122.0/2360.0.122.1 to 60.0.123.25460.0.123.255510
6360.0.124.0/2360.0.124.1 to 60.0.125.25460.0.125.255510
6460.0.126.0/2360.0.126.1 to 60.0.127.25460.0.127.255510
6560.0.128.0/2360.0.128.1 to 60.0.129.25460.0.129.255510
6660.0.130.0/2360.0.130.1 to 60.0.131.25460.0.131.255510
6760.0.132.0/2360.0.132.1 to 60.0.133.25460.0.133.255510
6860.0.134.0/2360.0.134.1 to 60.0.135.25460.0.135.255510
6960.0.136.0/2360.0.136.1 to 60.0.137.25460.0.137.255510
7060.0.138.0/2360.0.138.1 to 60.0.139.25460.0.139.255510
7160.0.140.0/2360.0.140.1 to 60.0.141.25460.0.141.255510
7260.0.142.0/2360.0.142.1 to 60.0.143.25460.0.143.255510
7360.0.144.0/2360.0.144.1 to 60.0.145.25460.0.145.255510
7460.0.146.0/2360.0.146.1 to 60.0.147.25460.0.147.255510
7560.0.148.0/2360.0.148.1 to 60.0.149.25460.0.149.255510
7660.0.150.0/2360.0.150.1 to 60.0.151.25460.0.151.255510
7760.0.152.0/2360.0.152.1 to 60.0.153.25460.0.153.255510
7860.0.154.0/2360.0.154.1 to 60.0.155.25460.0.155.255510
7960.0.156.0/2360.0.156.1 to 60.0.157.25460.0.157.255510
8060.0.158.0/2360.0.158.1 to 60.0.159.25460.0.159.255510
8160.0.160.0/2360.0.160.1 to 60.0.161.25460.0.161.255510
8260.0.162.0/2360.0.162.1 to 60.0.163.25460.0.163.255510
8360.0.164.0/2360.0.164.1 to 60.0.165.25460.0.165.255510
8460.0.166.0/2360.0.166.1 to 60.0.167.25460.0.167.255510
8560.0.168.0/2360.0.168.1 to 60.0.169.25460.0.169.255510
8660.0.170.0/2360.0.170.1 to 60.0.171.25460.0.171.255510
8760.0.172.0/2360.0.172.1 to 60.0.173.25460.0.173.255510
8860.0.174.0/2360.0.174.1 to 60.0.175.25460.0.175.255510
8960.0.176.0/2360.0.176.1 to 60.0.177.25460.0.177.255510
9060.0.178.0/2360.0.178.1 to 60.0.179.25460.0.179.255510
9160.0.180.0/2360.0.180.1 to 60.0.181.25460.0.181.255510
9260.0.182.0/2360.0.182.1 to 60.0.183.25460.0.183.255510
9360.0.184.0/2360.0.184.1 to 60.0.185.25460.0.185.255510
9460.0.186.0/2360.0.186.1 to 60.0.187.25460.0.187.255510
9560.0.188.0/2360.0.188.1 to 60.0.189.25460.0.189.255510
9660.0.190.0/2360.0.190.1 to 60.0.191.25460.0.191.255510
9760.0.192.0/2360.0.192.1 to 60.0.193.25460.0.193.255510
9860.0.194.0/2360.0.194.1 to 60.0.195.25460.0.195.255510
9960.0.196.0/2360.0.196.1 to 60.0.197.25460.0.197.255510
10060.0.198.0/2360.0.198.1 to 60.0.199.25460.0.199.255510
10160.0.200.0/2360.0.200.1 to 60.0.201.25460.0.201.255510
10260.0.202.0/2360.0.202.1 to 60.0.203.25460.0.203.255510
10360.0.204.0/2360.0.204.1 to 60.0.205.25460.0.205.255510
10460.0.206.0/2360.0.206.1 to 60.0.207.25460.0.207.255510
10560.0.208.0/2360.0.208.1 to 60.0.209.25460.0.209.255510
10660.0.210.0/2360.0.210.1 to 60.0.211.25460.0.211.255510
10760.0.212.0/2360.0.212.1 to 60.0.213.25460.0.213.255510
10860.0.214.0/2360.0.214.1 to 60.0.215.25460.0.215.255510
10960.0.216.0/2360.0.216.1 to 60.0.217.25460.0.217.255510
11060.0.218.0/2360.0.218.1 to 60.0.219.25460.0.219.255510
11160.0.220.0/2360.0.220.1 to 60.0.221.25460.0.221.255510
11260.0.222.0/2360.0.222.1 to 60.0.223.25460.0.223.255510
11360.0.224.0/2360.0.224.1 to 60.0.225.25460.0.225.255510
11460.0.226.0/2360.0.226.1 to 60.0.227.25460.0.227.255510
11560.0.228.0/2360.0.228.1 to 60.0.229.25460.0.229.255510
11660.0.230.0/2360.0.230.1 to 60.0.231.25460.0.231.255510
11760.0.232.0/2360.0.232.1 to 60.0.233.25460.0.233.255510
11860.0.234.0/2360.0.234.1 to 60.0.235.25460.0.235.255510
11960.0.236.0/2360.0.236.1 to 60.0.237.25460.0.237.255510
12060.0.238.0/2360.0.238.1 to 60.0.239.25460.0.239.255510
12160.0.240.0/2360.0.240.1 to 60.0.241.25460.0.241.255510
12260.0.242.0/2360.0.242.1 to 60.0.243.25460.0.243.255510
12360.0.244.0/2360.0.244.1 to 60.0.245.25460.0.245.255510
12460.0.246.0/2360.0.246.1 to 60.0.247.25460.0.247.255510
12560.0.248.0/2360.0.248.1 to 60.0.249.25460.0.249.255510
12660.0.250.0/2360.0.250.1 to 60.0.251.25460.0.251.255510
12760.0.252.0/2360.0.252.1 to 60.0.253.25460.0.253.255510
12860.0.254.0/2360.0.254.1 to 60.0.255.25460.0.255.255510
12960.1.0.0/2360.1.0.1 to 60.1.1.25460.1.1.255510
13060.1.2.0/2360.1.2.1 to 60.1.3.25460.1.3.255510
13160.1.4.0/2360.1.4.1 to 60.1.5.25460.1.5.255510
13260.1.6.0/2360.1.6.1 to 60.1.7.25460.1.7.255510
13360.1.8.0/2360.1.8.1 to 60.1.9.25460.1.9.255510
13460.1.10.0/2360.1.10.1 to 60.1.11.25460.1.11.255510
13560.1.12.0/2360.1.12.1 to 60.1.13.25460.1.13.255510
13660.1.14.0/2360.1.14.1 to 60.1.15.25460.1.15.255510
13760.1.16.0/2360.1.16.1 to 60.1.17.25460.1.17.255510
13860.1.18.0/2360.1.18.1 to 60.1.19.25460.1.19.255510
13960.1.20.0/2360.1.20.1 to 60.1.21.25460.1.21.255510
14060.1.22.0/2360.1.22.1 to 60.1.23.25460.1.23.255510
14160.1.24.0/2360.1.24.1 to 60.1.25.25460.1.25.255510
14260.1.26.0/2360.1.26.1 to 60.1.27.25460.1.27.255510
14360.1.28.0/2360.1.28.1 to 60.1.29.25460.1.29.255510
14460.1.30.0/2360.1.30.1 to 60.1.31.25460.1.31.255510
14560.1.32.0/2360.1.32.1 to 60.1.33.25460.1.33.255510
14660.1.34.0/2360.1.34.1 to 60.1.35.25460.1.35.255510
14760.1.36.0/2360.1.36.1 to 60.1.37.25460.1.37.255510
14860.1.38.0/2360.1.38.1 to 60.1.39.25460.1.39.255510
14960.1.40.0/2360.1.40.1 to 60.1.41.25460.1.41.255510
15060.1.42.0/2360.1.42.1 to 60.1.43.25460.1.43.255510
15160.1.44.0/2360.1.44.1 to 60.1.45.25460.1.45.255510
15260.1.46.0/2360.1.46.1 to 60.1.47.25460.1.47.255510
15360.1.48.0/2360.1.48.1 to 60.1.49.25460.1.49.255510
15460.1.50.0/2360.1.50.1 to 60.1.51.25460.1.51.255510
15560.1.52.0/2360.1.52.1 to 60.1.53.25460.1.53.255510
15660.1.54.0/2360.1.54.1 to 60.1.55.25460.1.55.255510
15760.1.56.0/2360.1.56.1 to 60.1.57.25460.1.57.255510
15860.1.58.0/2360.1.58.1 to 60.1.59.25460.1.59.255510
15960.1.60.0/2360.1.60.1 to 60.1.61.25460.1.61.255510
16060.1.62.0/2360.1.62.1 to 60.1.63.25460.1.63.255510
16160.1.64.0/2360.1.64.1 to 60.1.65.25460.1.65.255510
16260.1.66.0/2360.1.66.1 to 60.1.67.25460.1.67.255510
16360.1.68.0/2360.1.68.1 to 60.1.69.25460.1.69.255510
16460.1.70.0/2360.1.70.1 to 60.1.71.25460.1.71.255510
16560.1.72.0/2360.1.72.1 to 60.1.73.25460.1.73.255510
16660.1.74.0/2360.1.74.1 to 60.1.75.25460.1.75.255510
16760.1.76.0/2360.1.76.1 to 60.1.77.25460.1.77.255510
16860.1.78.0/2360.1.78.1 to 60.1.79.25460.1.79.255510
16960.1.80.0/2360.1.80.1 to 60.1.81.25460.1.81.255510
17060.1.82.0/2360.1.82.1 to 60.1.83.25460.1.83.255510
17160.1.84.0/2360.1.84.1 to 60.1.85.25460.1.85.255510
17260.1.86.0/2360.1.86.1 to 60.1.87.25460.1.87.255510
17360.1.88.0/2360.1.88.1 to 60.1.89.25460.1.89.255510
17460.1.90.0/2360.1.90.1 to 60.1.91.25460.1.91.255510
17560.1.92.0/2360.1.92.1 to 60.1.93.25460.1.93.255510
17660.1.94.0/2360.1.94.1 to 60.1.95.25460.1.95.255510
17760.1.96.0/2360.1.96.1 to 60.1.97.25460.1.97.255510
17860.1.98.0/2360.1.98.1 to 60.1.99.25460.1.99.255510
17960.1.100.0/2360.1.100.1 to 60.1.101.25460.1.101.255510
18060.1.102.0/2360.1.102.1 to 60.1.103.25460.1.103.255510
18160.1.104.0/2360.1.104.1 to 60.1.105.25460.1.105.255510
18260.1.106.0/2360.1.106.1 to 60.1.107.25460.1.107.255510
18360.1.108.0/2360.1.108.1 to 60.1.109.25460.1.109.255510
18460.1.110.0/2360.1.110.1 to 60.1.111.25460.1.111.255510
18560.1.112.0/2360.1.112.1 to 60.1.113.25460.1.113.255510
18660.1.114.0/2360.1.114.1 to 60.1.115.25460.1.115.255510
18760.1.116.0/2360.1.116.1 to 60.1.117.25460.1.117.255510
18860.1.118.0/2360.1.118.1 to 60.1.119.25460.1.119.255510
18960.1.120.0/2360.1.120.1 to 60.1.121.25460.1.121.255510
19060.1.122.0/2360.1.122.1 to 60.1.123.25460.1.123.255510
19160.1.124.0/2360.1.124.1 to 60.1.125.25460.1.125.255510
19260.1.126.0/2360.1.126.1 to 60.1.127.25460.1.127.255510
19360.1.128.0/2360.1.128.1 to 60.1.129.25460.1.129.255510
19460.1.130.0/2360.1.130.1 to 60.1.131.25460.1.131.255510
19560.1.132.0/2360.1.132.1 to 60.1.133.25460.1.133.255510
19660.1.134.0/2360.1.134.1 to 60.1.135.25460.1.135.255510
19760.1.136.0/2360.1.136.1 to 60.1.137.25460.1.137.255510
19860.1.138.0/2360.1.138.1 to 60.1.139.25460.1.139.255510
19960.1.140.0/2360.1.140.1 to 60.1.141.25460.1.141.255510
20060.1.142.0/2360.1.142.1 to 60.1.143.25460.1.143.255510
20160.1.144.0/2360.1.144.1 to 60.1.145.25460.1.145.255510
20260.1.146.0/2360.1.146.1 to 60.1.147.25460.1.147.255510
20360.1.148.0/2360.1.148.1 to 60.1.149.25460.1.149.255510
20460.1.150.0/2360.1.150.1 to 60.1.151.25460.1.151.255510
20560.1.152.0/2360.1.152.1 to 60.1.153.25460.1.153.255510
20660.1.154.0/2360.1.154.1 to 60.1.155.25460.1.155.255510
20760.1.156.0/2360.1.156.1 to 60.1.157.25460.1.157.255510
20860.1.158.0/2360.1.158.1 to 60.1.159.25460.1.159.255510
20960.1.160.0/2360.1.160.1 to 60.1.161.25460.1.161.255510
21060.1.162.0/2360.1.162.1 to 60.1.163.25460.1.163.255510
21160.1.164.0/2360.1.164.1 to 60.1.165.25460.1.165.255510
21260.1.166.0/2360.1.166.1 to 60.1.167.25460.1.167.255510
21360.1.168.0/2360.1.168.1 to 60.1.169.25460.1.169.255510
21460.1.170.0/2360.1.170.1 to 60.1.171.25460.1.171.255510
21560.1.172.0/2360.1.172.1 to 60.1.173.25460.1.173.255510
21660.1.174.0/2360.1.174.1 to 60.1.175.25460.1.175.255510
21760.1.176.0/2360.1.176.1 to 60.1.177.25460.1.177.255510
21860.1.178.0/2360.1.178.1 to 60.1.179.25460.1.179.255510
21960.1.180.0/2360.1.180.1 to 60.1.181.25460.1.181.255510
22060.1.182.0/2360.1.182.1 to 60.1.183.25460.1.183.255510
22160.1.184.0/2360.1.184.1 to 60.1.185.25460.1.185.255510
22260.1.186.0/2360.1.186.1 to 60.1.187.25460.1.187.255510
22360.1.188.0/2360.1.188.1 to 60.1.189.25460.1.189.255510
22460.1.190.0/2360.1.190.1 to 60.1.191.25460.1.191.255510
22560.1.192.0/2360.1.192.1 to 60.1.193.25460.1.193.255510
22660.1.194.0/2360.1.194.1 to 60.1.195.25460.1.195.255510
22760.1.196.0/2360.1.196.1 to 60.1.197.25460.1.197.255510
22860.1.198.0/2360.1.198.1 to 60.1.199.25460.1.199.255510
22960.1.200.0/2360.1.200.1 to 60.1.201.25460.1.201.255510
23060.1.202.0/2360.1.202.1 to 60.1.203.25460.1.203.255510
23160.1.204.0/2360.1.204.1 to 60.1.205.25460.1.205.255510
23260.1.206.0/2360.1.206.1 to 60.1.207.25460.1.207.255510
23360.1.208.0/2360.1.208.1 to 60.1.209.25460.1.209.255510
23460.1.210.0/2360.1.210.1 to 60.1.211.25460.1.211.255510
23560.1.212.0/2360.1.212.1 to 60.1.213.25460.1.213.255510
23660.1.214.0/2360.1.214.1 to 60.1.215.25460.1.215.255510
23760.1.216.0/2360.1.216.1 to 60.1.217.25460.1.217.255510
23860.1.218.0/2360.1.218.1 to 60.1.219.25460.1.219.255510
23960.1.220.0/2360.1.220.1 to 60.1.221.25460.1.221.255510
24060.1.222.0/2360.1.222.1 to 60.1.223.25460.1.223.255510
24160.1.224.0/2360.1.224.1 to 60.1.225.25460.1.225.255510
24260.1.226.0/2360.1.226.1 to 60.1.227.25460.1.227.255510
24360.1.228.0/2360.1.228.1 to 60.1.229.25460.1.229.255510
24460.1.230.0/2360.1.230.1 to 60.1.231.25460.1.231.255510
24560.1.232.0/2360.1.232.1 to 60.1.233.25460.1.233.255510
24660.1.234.0/2360.1.234.1 to 60.1.235.25460.1.235.255510
24760.1.236.0/2360.1.236.1 to 60.1.237.25460.1.237.255510
24860.1.238.0/2360.1.238.1 to 60.1.239.25460.1.239.255510
24960.1.240.0/2360.1.240.1 to 60.1.241.25460.1.241.255510
25060.1.242.0/2360.1.242.1 to 60.1.243.25460.1.243.255510
25160.1.244.0/2360.1.244.1 to 60.1.245.25460.1.245.255510
25260.1.246.0/2360.1.246.1 to 60.1.247.25460.1.247.255510
25360.1.248.0/2360.1.248.1 to 60.1.249.25460.1.249.255510
25460.1.250.0/2360.1.250.1 to 60.1.251.25460.1.251.255510
25560.1.252.0/2360.1.252.1 to 60.1.253.25460.1.253.255510
25660.1.254.0/2360.1.254.1 to 60.1.255.25460.1.255.255510

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.