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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.

Network95.64.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
95.64.0.0
Broadcast address
95.67.255.255
First usable
95.64.0.1
Last usable
95.67.255.254
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 5F400000 · Integer 1598029824 to 1598291967
Reverse DNS zones
64.95.in-addr.arpa
65.95.in-addr.arpa
66.95.in-addr.arpa
67.95.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
Address01011111.01000000.00000000.0000000095.64.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01011111.01000000.00000000.0000000095.64.0.0
Broadcast01011111.01000011.11111111.1111111195.67.255.255
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)

95.64.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
195.64.0.0/2395.64.0.1 to 95.64.1.25495.64.1.255510
295.64.2.0/2395.64.2.1 to 95.64.3.25495.64.3.255510
395.64.4.0/2395.64.4.1 to 95.64.5.25495.64.5.255510
495.64.6.0/2395.64.6.1 to 95.64.7.25495.64.7.255510
595.64.8.0/2395.64.8.1 to 95.64.9.25495.64.9.255510
695.64.10.0/2395.64.10.1 to 95.64.11.25495.64.11.255510
795.64.12.0/2395.64.12.1 to 95.64.13.25495.64.13.255510
895.64.14.0/2395.64.14.1 to 95.64.15.25495.64.15.255510
995.64.16.0/2395.64.16.1 to 95.64.17.25495.64.17.255510
1095.64.18.0/2395.64.18.1 to 95.64.19.25495.64.19.255510
1195.64.20.0/2395.64.20.1 to 95.64.21.25495.64.21.255510
1295.64.22.0/2395.64.22.1 to 95.64.23.25495.64.23.255510
1395.64.24.0/2395.64.24.1 to 95.64.25.25495.64.25.255510
1495.64.26.0/2395.64.26.1 to 95.64.27.25495.64.27.255510
1595.64.28.0/2395.64.28.1 to 95.64.29.25495.64.29.255510
1695.64.30.0/2395.64.30.1 to 95.64.31.25495.64.31.255510
1795.64.32.0/2395.64.32.1 to 95.64.33.25495.64.33.255510
1895.64.34.0/2395.64.34.1 to 95.64.35.25495.64.35.255510
1995.64.36.0/2395.64.36.1 to 95.64.37.25495.64.37.255510
2095.64.38.0/2395.64.38.1 to 95.64.39.25495.64.39.255510
2195.64.40.0/2395.64.40.1 to 95.64.41.25495.64.41.255510
2295.64.42.0/2395.64.42.1 to 95.64.43.25495.64.43.255510
2395.64.44.0/2395.64.44.1 to 95.64.45.25495.64.45.255510
2495.64.46.0/2395.64.46.1 to 95.64.47.25495.64.47.255510
2595.64.48.0/2395.64.48.1 to 95.64.49.25495.64.49.255510
2695.64.50.0/2395.64.50.1 to 95.64.51.25495.64.51.255510
2795.64.52.0/2395.64.52.1 to 95.64.53.25495.64.53.255510
2895.64.54.0/2395.64.54.1 to 95.64.55.25495.64.55.255510
2995.64.56.0/2395.64.56.1 to 95.64.57.25495.64.57.255510
3095.64.58.0/2395.64.58.1 to 95.64.59.25495.64.59.255510
3195.64.60.0/2395.64.60.1 to 95.64.61.25495.64.61.255510
3295.64.62.0/2395.64.62.1 to 95.64.63.25495.64.63.255510
3395.64.64.0/2395.64.64.1 to 95.64.65.25495.64.65.255510
3495.64.66.0/2395.64.66.1 to 95.64.67.25495.64.67.255510
3595.64.68.0/2395.64.68.1 to 95.64.69.25495.64.69.255510
3695.64.70.0/2395.64.70.1 to 95.64.71.25495.64.71.255510
3795.64.72.0/2395.64.72.1 to 95.64.73.25495.64.73.255510
3895.64.74.0/2395.64.74.1 to 95.64.75.25495.64.75.255510
3995.64.76.0/2395.64.76.1 to 95.64.77.25495.64.77.255510
4095.64.78.0/2395.64.78.1 to 95.64.79.25495.64.79.255510
4195.64.80.0/2395.64.80.1 to 95.64.81.25495.64.81.255510
4295.64.82.0/2395.64.82.1 to 95.64.83.25495.64.83.255510
4395.64.84.0/2395.64.84.1 to 95.64.85.25495.64.85.255510
4495.64.86.0/2395.64.86.1 to 95.64.87.25495.64.87.255510
4595.64.88.0/2395.64.88.1 to 95.64.89.25495.64.89.255510
4695.64.90.0/2395.64.90.1 to 95.64.91.25495.64.91.255510
4795.64.92.0/2395.64.92.1 to 95.64.93.25495.64.93.255510
4895.64.94.0/2395.64.94.1 to 95.64.95.25495.64.95.255510
4995.64.96.0/2395.64.96.1 to 95.64.97.25495.64.97.255510
5095.64.98.0/2395.64.98.1 to 95.64.99.25495.64.99.255510
5195.64.100.0/2395.64.100.1 to 95.64.101.25495.64.101.255510
5295.64.102.0/2395.64.102.1 to 95.64.103.25495.64.103.255510
5395.64.104.0/2395.64.104.1 to 95.64.105.25495.64.105.255510
5495.64.106.0/2395.64.106.1 to 95.64.107.25495.64.107.255510
5595.64.108.0/2395.64.108.1 to 95.64.109.25495.64.109.255510
5695.64.110.0/2395.64.110.1 to 95.64.111.25495.64.111.255510
5795.64.112.0/2395.64.112.1 to 95.64.113.25495.64.113.255510
5895.64.114.0/2395.64.114.1 to 95.64.115.25495.64.115.255510
5995.64.116.0/2395.64.116.1 to 95.64.117.25495.64.117.255510
6095.64.118.0/2395.64.118.1 to 95.64.119.25495.64.119.255510
6195.64.120.0/2395.64.120.1 to 95.64.121.25495.64.121.255510
6295.64.122.0/2395.64.122.1 to 95.64.123.25495.64.123.255510
6395.64.124.0/2395.64.124.1 to 95.64.125.25495.64.125.255510
6495.64.126.0/2395.64.126.1 to 95.64.127.25495.64.127.255510
6595.64.128.0/2395.64.128.1 to 95.64.129.25495.64.129.255510
6695.64.130.0/2395.64.130.1 to 95.64.131.25495.64.131.255510
6795.64.132.0/2395.64.132.1 to 95.64.133.25495.64.133.255510
6895.64.134.0/2395.64.134.1 to 95.64.135.25495.64.135.255510
6995.64.136.0/2395.64.136.1 to 95.64.137.25495.64.137.255510
7095.64.138.0/2395.64.138.1 to 95.64.139.25495.64.139.255510
7195.64.140.0/2395.64.140.1 to 95.64.141.25495.64.141.255510
7295.64.142.0/2395.64.142.1 to 95.64.143.25495.64.143.255510
7395.64.144.0/2395.64.144.1 to 95.64.145.25495.64.145.255510
7495.64.146.0/2395.64.146.1 to 95.64.147.25495.64.147.255510
7595.64.148.0/2395.64.148.1 to 95.64.149.25495.64.149.255510
7695.64.150.0/2395.64.150.1 to 95.64.151.25495.64.151.255510
7795.64.152.0/2395.64.152.1 to 95.64.153.25495.64.153.255510
7895.64.154.0/2395.64.154.1 to 95.64.155.25495.64.155.255510
7995.64.156.0/2395.64.156.1 to 95.64.157.25495.64.157.255510
8095.64.158.0/2395.64.158.1 to 95.64.159.25495.64.159.255510
8195.64.160.0/2395.64.160.1 to 95.64.161.25495.64.161.255510
8295.64.162.0/2395.64.162.1 to 95.64.163.25495.64.163.255510
8395.64.164.0/2395.64.164.1 to 95.64.165.25495.64.165.255510
8495.64.166.0/2395.64.166.1 to 95.64.167.25495.64.167.255510
8595.64.168.0/2395.64.168.1 to 95.64.169.25495.64.169.255510
8695.64.170.0/2395.64.170.1 to 95.64.171.25495.64.171.255510
8795.64.172.0/2395.64.172.1 to 95.64.173.25495.64.173.255510
8895.64.174.0/2395.64.174.1 to 95.64.175.25495.64.175.255510
8995.64.176.0/2395.64.176.1 to 95.64.177.25495.64.177.255510
9095.64.178.0/2395.64.178.1 to 95.64.179.25495.64.179.255510
9195.64.180.0/2395.64.180.1 to 95.64.181.25495.64.181.255510
9295.64.182.0/2395.64.182.1 to 95.64.183.25495.64.183.255510
9395.64.184.0/2395.64.184.1 to 95.64.185.25495.64.185.255510
9495.64.186.0/2395.64.186.1 to 95.64.187.25495.64.187.255510
9595.64.188.0/2395.64.188.1 to 95.64.189.25495.64.189.255510
9695.64.190.0/2395.64.190.1 to 95.64.191.25495.64.191.255510
9795.64.192.0/2395.64.192.1 to 95.64.193.25495.64.193.255510
9895.64.194.0/2395.64.194.1 to 95.64.195.25495.64.195.255510
9995.64.196.0/2395.64.196.1 to 95.64.197.25495.64.197.255510
10095.64.198.0/2395.64.198.1 to 95.64.199.25495.64.199.255510
10195.64.200.0/2395.64.200.1 to 95.64.201.25495.64.201.255510
10295.64.202.0/2395.64.202.1 to 95.64.203.25495.64.203.255510
10395.64.204.0/2395.64.204.1 to 95.64.205.25495.64.205.255510
10495.64.206.0/2395.64.206.1 to 95.64.207.25495.64.207.255510
10595.64.208.0/2395.64.208.1 to 95.64.209.25495.64.209.255510
10695.64.210.0/2395.64.210.1 to 95.64.211.25495.64.211.255510
10795.64.212.0/2395.64.212.1 to 95.64.213.25495.64.213.255510
10895.64.214.0/2395.64.214.1 to 95.64.215.25495.64.215.255510
10995.64.216.0/2395.64.216.1 to 95.64.217.25495.64.217.255510
11095.64.218.0/2395.64.218.1 to 95.64.219.25495.64.219.255510
11195.64.220.0/2395.64.220.1 to 95.64.221.25495.64.221.255510
11295.64.222.0/2395.64.222.1 to 95.64.223.25495.64.223.255510
11395.64.224.0/2395.64.224.1 to 95.64.225.25495.64.225.255510
11495.64.226.0/2395.64.226.1 to 95.64.227.25495.64.227.255510
11595.64.228.0/2395.64.228.1 to 95.64.229.25495.64.229.255510
11695.64.230.0/2395.64.230.1 to 95.64.231.25495.64.231.255510
11795.64.232.0/2395.64.232.1 to 95.64.233.25495.64.233.255510
11895.64.234.0/2395.64.234.1 to 95.64.235.25495.64.235.255510
11995.64.236.0/2395.64.236.1 to 95.64.237.25495.64.237.255510
12095.64.238.0/2395.64.238.1 to 95.64.239.25495.64.239.255510
12195.64.240.0/2395.64.240.1 to 95.64.241.25495.64.241.255510
12295.64.242.0/2395.64.242.1 to 95.64.243.25495.64.243.255510
12395.64.244.0/2395.64.244.1 to 95.64.245.25495.64.245.255510
12495.64.246.0/2395.64.246.1 to 95.64.247.25495.64.247.255510
12595.64.248.0/2395.64.248.1 to 95.64.249.25495.64.249.255510
12695.64.250.0/2395.64.250.1 to 95.64.251.25495.64.251.255510
12795.64.252.0/2395.64.252.1 to 95.64.253.25495.64.253.255510
12895.64.254.0/2395.64.254.1 to 95.64.255.25495.64.255.255510
12995.65.0.0/2395.65.0.1 to 95.65.1.25495.65.1.255510
13095.65.2.0/2395.65.2.1 to 95.65.3.25495.65.3.255510
13195.65.4.0/2395.65.4.1 to 95.65.5.25495.65.5.255510
13295.65.6.0/2395.65.6.1 to 95.65.7.25495.65.7.255510
13395.65.8.0/2395.65.8.1 to 95.65.9.25495.65.9.255510
13495.65.10.0/2395.65.10.1 to 95.65.11.25495.65.11.255510
13595.65.12.0/2395.65.12.1 to 95.65.13.25495.65.13.255510
13695.65.14.0/2395.65.14.1 to 95.65.15.25495.65.15.255510
13795.65.16.0/2395.65.16.1 to 95.65.17.25495.65.17.255510
13895.65.18.0/2395.65.18.1 to 95.65.19.25495.65.19.255510
13995.65.20.0/2395.65.20.1 to 95.65.21.25495.65.21.255510
14095.65.22.0/2395.65.22.1 to 95.65.23.25495.65.23.255510
14195.65.24.0/2395.65.24.1 to 95.65.25.25495.65.25.255510
14295.65.26.0/2395.65.26.1 to 95.65.27.25495.65.27.255510
14395.65.28.0/2395.65.28.1 to 95.65.29.25495.65.29.255510
14495.65.30.0/2395.65.30.1 to 95.65.31.25495.65.31.255510
14595.65.32.0/2395.65.32.1 to 95.65.33.25495.65.33.255510
14695.65.34.0/2395.65.34.1 to 95.65.35.25495.65.35.255510
14795.65.36.0/2395.65.36.1 to 95.65.37.25495.65.37.255510
14895.65.38.0/2395.65.38.1 to 95.65.39.25495.65.39.255510
14995.65.40.0/2395.65.40.1 to 95.65.41.25495.65.41.255510
15095.65.42.0/2395.65.42.1 to 95.65.43.25495.65.43.255510
15195.65.44.0/2395.65.44.1 to 95.65.45.25495.65.45.255510
15295.65.46.0/2395.65.46.1 to 95.65.47.25495.65.47.255510
15395.65.48.0/2395.65.48.1 to 95.65.49.25495.65.49.255510
15495.65.50.0/2395.65.50.1 to 95.65.51.25495.65.51.255510
15595.65.52.0/2395.65.52.1 to 95.65.53.25495.65.53.255510
15695.65.54.0/2395.65.54.1 to 95.65.55.25495.65.55.255510
15795.65.56.0/2395.65.56.1 to 95.65.57.25495.65.57.255510
15895.65.58.0/2395.65.58.1 to 95.65.59.25495.65.59.255510
15995.65.60.0/2395.65.60.1 to 95.65.61.25495.65.61.255510
16095.65.62.0/2395.65.62.1 to 95.65.63.25495.65.63.255510
16195.65.64.0/2395.65.64.1 to 95.65.65.25495.65.65.255510
16295.65.66.0/2395.65.66.1 to 95.65.67.25495.65.67.255510
16395.65.68.0/2395.65.68.1 to 95.65.69.25495.65.69.255510
16495.65.70.0/2395.65.70.1 to 95.65.71.25495.65.71.255510
16595.65.72.0/2395.65.72.1 to 95.65.73.25495.65.73.255510
16695.65.74.0/2395.65.74.1 to 95.65.75.25495.65.75.255510
16795.65.76.0/2395.65.76.1 to 95.65.77.25495.65.77.255510
16895.65.78.0/2395.65.78.1 to 95.65.79.25495.65.79.255510
16995.65.80.0/2395.65.80.1 to 95.65.81.25495.65.81.255510
17095.65.82.0/2395.65.82.1 to 95.65.83.25495.65.83.255510
17195.65.84.0/2395.65.84.1 to 95.65.85.25495.65.85.255510
17295.65.86.0/2395.65.86.1 to 95.65.87.25495.65.87.255510
17395.65.88.0/2395.65.88.1 to 95.65.89.25495.65.89.255510
17495.65.90.0/2395.65.90.1 to 95.65.91.25495.65.91.255510
17595.65.92.0/2395.65.92.1 to 95.65.93.25495.65.93.255510
17695.65.94.0/2395.65.94.1 to 95.65.95.25495.65.95.255510
17795.65.96.0/2395.65.96.1 to 95.65.97.25495.65.97.255510
17895.65.98.0/2395.65.98.1 to 95.65.99.25495.65.99.255510
17995.65.100.0/2395.65.100.1 to 95.65.101.25495.65.101.255510
18095.65.102.0/2395.65.102.1 to 95.65.103.25495.65.103.255510
18195.65.104.0/2395.65.104.1 to 95.65.105.25495.65.105.255510
18295.65.106.0/2395.65.106.1 to 95.65.107.25495.65.107.255510
18395.65.108.0/2395.65.108.1 to 95.65.109.25495.65.109.255510
18495.65.110.0/2395.65.110.1 to 95.65.111.25495.65.111.255510
18595.65.112.0/2395.65.112.1 to 95.65.113.25495.65.113.255510
18695.65.114.0/2395.65.114.1 to 95.65.115.25495.65.115.255510
18795.65.116.0/2395.65.116.1 to 95.65.117.25495.65.117.255510
18895.65.118.0/2395.65.118.1 to 95.65.119.25495.65.119.255510
18995.65.120.0/2395.65.120.1 to 95.65.121.25495.65.121.255510
19095.65.122.0/2395.65.122.1 to 95.65.123.25495.65.123.255510
19195.65.124.0/2395.65.124.1 to 95.65.125.25495.65.125.255510
19295.65.126.0/2395.65.126.1 to 95.65.127.25495.65.127.255510
19395.65.128.0/2395.65.128.1 to 95.65.129.25495.65.129.255510
19495.65.130.0/2395.65.130.1 to 95.65.131.25495.65.131.255510
19595.65.132.0/2395.65.132.1 to 95.65.133.25495.65.133.255510
19695.65.134.0/2395.65.134.1 to 95.65.135.25495.65.135.255510
19795.65.136.0/2395.65.136.1 to 95.65.137.25495.65.137.255510
19895.65.138.0/2395.65.138.1 to 95.65.139.25495.65.139.255510
19995.65.140.0/2395.65.140.1 to 95.65.141.25495.65.141.255510
20095.65.142.0/2395.65.142.1 to 95.65.143.25495.65.143.255510
20195.65.144.0/2395.65.144.1 to 95.65.145.25495.65.145.255510
20295.65.146.0/2395.65.146.1 to 95.65.147.25495.65.147.255510
20395.65.148.0/2395.65.148.1 to 95.65.149.25495.65.149.255510
20495.65.150.0/2395.65.150.1 to 95.65.151.25495.65.151.255510
20595.65.152.0/2395.65.152.1 to 95.65.153.25495.65.153.255510
20695.65.154.0/2395.65.154.1 to 95.65.155.25495.65.155.255510
20795.65.156.0/2395.65.156.1 to 95.65.157.25495.65.157.255510
20895.65.158.0/2395.65.158.1 to 95.65.159.25495.65.159.255510
20995.65.160.0/2395.65.160.1 to 95.65.161.25495.65.161.255510
21095.65.162.0/2395.65.162.1 to 95.65.163.25495.65.163.255510
21195.65.164.0/2395.65.164.1 to 95.65.165.25495.65.165.255510
21295.65.166.0/2395.65.166.1 to 95.65.167.25495.65.167.255510
21395.65.168.0/2395.65.168.1 to 95.65.169.25495.65.169.255510
21495.65.170.0/2395.65.170.1 to 95.65.171.25495.65.171.255510
21595.65.172.0/2395.65.172.1 to 95.65.173.25495.65.173.255510
21695.65.174.0/2395.65.174.1 to 95.65.175.25495.65.175.255510
21795.65.176.0/2395.65.176.1 to 95.65.177.25495.65.177.255510
21895.65.178.0/2395.65.178.1 to 95.65.179.25495.65.179.255510
21995.65.180.0/2395.65.180.1 to 95.65.181.25495.65.181.255510
22095.65.182.0/2395.65.182.1 to 95.65.183.25495.65.183.255510
22195.65.184.0/2395.65.184.1 to 95.65.185.25495.65.185.255510
22295.65.186.0/2395.65.186.1 to 95.65.187.25495.65.187.255510
22395.65.188.0/2395.65.188.1 to 95.65.189.25495.65.189.255510
22495.65.190.0/2395.65.190.1 to 95.65.191.25495.65.191.255510
22595.65.192.0/2395.65.192.1 to 95.65.193.25495.65.193.255510
22695.65.194.0/2395.65.194.1 to 95.65.195.25495.65.195.255510
22795.65.196.0/2395.65.196.1 to 95.65.197.25495.65.197.255510
22895.65.198.0/2395.65.198.1 to 95.65.199.25495.65.199.255510
22995.65.200.0/2395.65.200.1 to 95.65.201.25495.65.201.255510
23095.65.202.0/2395.65.202.1 to 95.65.203.25495.65.203.255510
23195.65.204.0/2395.65.204.1 to 95.65.205.25495.65.205.255510
23295.65.206.0/2395.65.206.1 to 95.65.207.25495.65.207.255510
23395.65.208.0/2395.65.208.1 to 95.65.209.25495.65.209.255510
23495.65.210.0/2395.65.210.1 to 95.65.211.25495.65.211.255510
23595.65.212.0/2395.65.212.1 to 95.65.213.25495.65.213.255510
23695.65.214.0/2395.65.214.1 to 95.65.215.25495.65.215.255510
23795.65.216.0/2395.65.216.1 to 95.65.217.25495.65.217.255510
23895.65.218.0/2395.65.218.1 to 95.65.219.25495.65.219.255510
23995.65.220.0/2395.65.220.1 to 95.65.221.25495.65.221.255510
24095.65.222.0/2395.65.222.1 to 95.65.223.25495.65.223.255510
24195.65.224.0/2395.65.224.1 to 95.65.225.25495.65.225.255510
24295.65.226.0/2395.65.226.1 to 95.65.227.25495.65.227.255510
24395.65.228.0/2395.65.228.1 to 95.65.229.25495.65.229.255510
24495.65.230.0/2395.65.230.1 to 95.65.231.25495.65.231.255510
24595.65.232.0/2395.65.232.1 to 95.65.233.25495.65.233.255510
24695.65.234.0/2395.65.234.1 to 95.65.235.25495.65.235.255510
24795.65.236.0/2395.65.236.1 to 95.65.237.25495.65.237.255510
24895.65.238.0/2395.65.238.1 to 95.65.239.25495.65.239.255510
24995.65.240.0/2395.65.240.1 to 95.65.241.25495.65.241.255510
25095.65.242.0/2395.65.242.1 to 95.65.243.25495.65.243.255510
25195.65.244.0/2395.65.244.1 to 95.65.245.25495.65.245.255510
25295.65.246.0/2395.65.246.1 to 95.65.247.25495.65.247.255510
25395.65.248.0/2395.65.248.1 to 95.65.249.25495.65.249.255510
25495.65.250.0/2395.65.250.1 to 95.65.251.25495.65.251.255510
25595.65.252.0/2395.65.252.1 to 95.65.253.25495.65.253.255510
25695.65.254.0/2395.65.254.1 to 95.65.255.25495.65.255.255510

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.