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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.

Network44.68.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
44.68.0.0
Broadcast address
44.71.255.255
First usable
44.68.0.1
Last usable
44.71.255.254
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 2C440000 · Integer 742653952 to 742916095
Reverse DNS zones
68.44.in-addr.arpa
69.44.in-addr.arpa
70.44.in-addr.arpa
71.44.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
Address00101100.01000100.00000000.0000000044.68.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00101100.01000100.00000000.0000000044.68.0.0
Broadcast00101100.01000111.11111111.1111111144.71.255.255
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)

44.68.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
144.68.0.0/2344.68.0.1 to 44.68.1.25444.68.1.255510
244.68.2.0/2344.68.2.1 to 44.68.3.25444.68.3.255510
344.68.4.0/2344.68.4.1 to 44.68.5.25444.68.5.255510
444.68.6.0/2344.68.6.1 to 44.68.7.25444.68.7.255510
544.68.8.0/2344.68.8.1 to 44.68.9.25444.68.9.255510
644.68.10.0/2344.68.10.1 to 44.68.11.25444.68.11.255510
744.68.12.0/2344.68.12.1 to 44.68.13.25444.68.13.255510
844.68.14.0/2344.68.14.1 to 44.68.15.25444.68.15.255510
944.68.16.0/2344.68.16.1 to 44.68.17.25444.68.17.255510
1044.68.18.0/2344.68.18.1 to 44.68.19.25444.68.19.255510
1144.68.20.0/2344.68.20.1 to 44.68.21.25444.68.21.255510
1244.68.22.0/2344.68.22.1 to 44.68.23.25444.68.23.255510
1344.68.24.0/2344.68.24.1 to 44.68.25.25444.68.25.255510
1444.68.26.0/2344.68.26.1 to 44.68.27.25444.68.27.255510
1544.68.28.0/2344.68.28.1 to 44.68.29.25444.68.29.255510
1644.68.30.0/2344.68.30.1 to 44.68.31.25444.68.31.255510
1744.68.32.0/2344.68.32.1 to 44.68.33.25444.68.33.255510
1844.68.34.0/2344.68.34.1 to 44.68.35.25444.68.35.255510
1944.68.36.0/2344.68.36.1 to 44.68.37.25444.68.37.255510
2044.68.38.0/2344.68.38.1 to 44.68.39.25444.68.39.255510
2144.68.40.0/2344.68.40.1 to 44.68.41.25444.68.41.255510
2244.68.42.0/2344.68.42.1 to 44.68.43.25444.68.43.255510
2344.68.44.0/2344.68.44.1 to 44.68.45.25444.68.45.255510
2444.68.46.0/2344.68.46.1 to 44.68.47.25444.68.47.255510
2544.68.48.0/2344.68.48.1 to 44.68.49.25444.68.49.255510
2644.68.50.0/2344.68.50.1 to 44.68.51.25444.68.51.255510
2744.68.52.0/2344.68.52.1 to 44.68.53.25444.68.53.255510
2844.68.54.0/2344.68.54.1 to 44.68.55.25444.68.55.255510
2944.68.56.0/2344.68.56.1 to 44.68.57.25444.68.57.255510
3044.68.58.0/2344.68.58.1 to 44.68.59.25444.68.59.255510
3144.68.60.0/2344.68.60.1 to 44.68.61.25444.68.61.255510
3244.68.62.0/2344.68.62.1 to 44.68.63.25444.68.63.255510
3344.68.64.0/2344.68.64.1 to 44.68.65.25444.68.65.255510
3444.68.66.0/2344.68.66.1 to 44.68.67.25444.68.67.255510
3544.68.68.0/2344.68.68.1 to 44.68.69.25444.68.69.255510
3644.68.70.0/2344.68.70.1 to 44.68.71.25444.68.71.255510
3744.68.72.0/2344.68.72.1 to 44.68.73.25444.68.73.255510
3844.68.74.0/2344.68.74.1 to 44.68.75.25444.68.75.255510
3944.68.76.0/2344.68.76.1 to 44.68.77.25444.68.77.255510
4044.68.78.0/2344.68.78.1 to 44.68.79.25444.68.79.255510
4144.68.80.0/2344.68.80.1 to 44.68.81.25444.68.81.255510
4244.68.82.0/2344.68.82.1 to 44.68.83.25444.68.83.255510
4344.68.84.0/2344.68.84.1 to 44.68.85.25444.68.85.255510
4444.68.86.0/2344.68.86.1 to 44.68.87.25444.68.87.255510
4544.68.88.0/2344.68.88.1 to 44.68.89.25444.68.89.255510
4644.68.90.0/2344.68.90.1 to 44.68.91.25444.68.91.255510
4744.68.92.0/2344.68.92.1 to 44.68.93.25444.68.93.255510
4844.68.94.0/2344.68.94.1 to 44.68.95.25444.68.95.255510
4944.68.96.0/2344.68.96.1 to 44.68.97.25444.68.97.255510
5044.68.98.0/2344.68.98.1 to 44.68.99.25444.68.99.255510
5144.68.100.0/2344.68.100.1 to 44.68.101.25444.68.101.255510
5244.68.102.0/2344.68.102.1 to 44.68.103.25444.68.103.255510
5344.68.104.0/2344.68.104.1 to 44.68.105.25444.68.105.255510
5444.68.106.0/2344.68.106.1 to 44.68.107.25444.68.107.255510
5544.68.108.0/2344.68.108.1 to 44.68.109.25444.68.109.255510
5644.68.110.0/2344.68.110.1 to 44.68.111.25444.68.111.255510
5744.68.112.0/2344.68.112.1 to 44.68.113.25444.68.113.255510
5844.68.114.0/2344.68.114.1 to 44.68.115.25444.68.115.255510
5944.68.116.0/2344.68.116.1 to 44.68.117.25444.68.117.255510
6044.68.118.0/2344.68.118.1 to 44.68.119.25444.68.119.255510
6144.68.120.0/2344.68.120.1 to 44.68.121.25444.68.121.255510
6244.68.122.0/2344.68.122.1 to 44.68.123.25444.68.123.255510
6344.68.124.0/2344.68.124.1 to 44.68.125.25444.68.125.255510
6444.68.126.0/2344.68.126.1 to 44.68.127.25444.68.127.255510
6544.68.128.0/2344.68.128.1 to 44.68.129.25444.68.129.255510
6644.68.130.0/2344.68.130.1 to 44.68.131.25444.68.131.255510
6744.68.132.0/2344.68.132.1 to 44.68.133.25444.68.133.255510
6844.68.134.0/2344.68.134.1 to 44.68.135.25444.68.135.255510
6944.68.136.0/2344.68.136.1 to 44.68.137.25444.68.137.255510
7044.68.138.0/2344.68.138.1 to 44.68.139.25444.68.139.255510
7144.68.140.0/2344.68.140.1 to 44.68.141.25444.68.141.255510
7244.68.142.0/2344.68.142.1 to 44.68.143.25444.68.143.255510
7344.68.144.0/2344.68.144.1 to 44.68.145.25444.68.145.255510
7444.68.146.0/2344.68.146.1 to 44.68.147.25444.68.147.255510
7544.68.148.0/2344.68.148.1 to 44.68.149.25444.68.149.255510
7644.68.150.0/2344.68.150.1 to 44.68.151.25444.68.151.255510
7744.68.152.0/2344.68.152.1 to 44.68.153.25444.68.153.255510
7844.68.154.0/2344.68.154.1 to 44.68.155.25444.68.155.255510
7944.68.156.0/2344.68.156.1 to 44.68.157.25444.68.157.255510
8044.68.158.0/2344.68.158.1 to 44.68.159.25444.68.159.255510
8144.68.160.0/2344.68.160.1 to 44.68.161.25444.68.161.255510
8244.68.162.0/2344.68.162.1 to 44.68.163.25444.68.163.255510
8344.68.164.0/2344.68.164.1 to 44.68.165.25444.68.165.255510
8444.68.166.0/2344.68.166.1 to 44.68.167.25444.68.167.255510
8544.68.168.0/2344.68.168.1 to 44.68.169.25444.68.169.255510
8644.68.170.0/2344.68.170.1 to 44.68.171.25444.68.171.255510
8744.68.172.0/2344.68.172.1 to 44.68.173.25444.68.173.255510
8844.68.174.0/2344.68.174.1 to 44.68.175.25444.68.175.255510
8944.68.176.0/2344.68.176.1 to 44.68.177.25444.68.177.255510
9044.68.178.0/2344.68.178.1 to 44.68.179.25444.68.179.255510
9144.68.180.0/2344.68.180.1 to 44.68.181.25444.68.181.255510
9244.68.182.0/2344.68.182.1 to 44.68.183.25444.68.183.255510
9344.68.184.0/2344.68.184.1 to 44.68.185.25444.68.185.255510
9444.68.186.0/2344.68.186.1 to 44.68.187.25444.68.187.255510
9544.68.188.0/2344.68.188.1 to 44.68.189.25444.68.189.255510
9644.68.190.0/2344.68.190.1 to 44.68.191.25444.68.191.255510
9744.68.192.0/2344.68.192.1 to 44.68.193.25444.68.193.255510
9844.68.194.0/2344.68.194.1 to 44.68.195.25444.68.195.255510
9944.68.196.0/2344.68.196.1 to 44.68.197.25444.68.197.255510
10044.68.198.0/2344.68.198.1 to 44.68.199.25444.68.199.255510
10144.68.200.0/2344.68.200.1 to 44.68.201.25444.68.201.255510
10244.68.202.0/2344.68.202.1 to 44.68.203.25444.68.203.255510
10344.68.204.0/2344.68.204.1 to 44.68.205.25444.68.205.255510
10444.68.206.0/2344.68.206.1 to 44.68.207.25444.68.207.255510
10544.68.208.0/2344.68.208.1 to 44.68.209.25444.68.209.255510
10644.68.210.0/2344.68.210.1 to 44.68.211.25444.68.211.255510
10744.68.212.0/2344.68.212.1 to 44.68.213.25444.68.213.255510
10844.68.214.0/2344.68.214.1 to 44.68.215.25444.68.215.255510
10944.68.216.0/2344.68.216.1 to 44.68.217.25444.68.217.255510
11044.68.218.0/2344.68.218.1 to 44.68.219.25444.68.219.255510
11144.68.220.0/2344.68.220.1 to 44.68.221.25444.68.221.255510
11244.68.222.0/2344.68.222.1 to 44.68.223.25444.68.223.255510
11344.68.224.0/2344.68.224.1 to 44.68.225.25444.68.225.255510
11444.68.226.0/2344.68.226.1 to 44.68.227.25444.68.227.255510
11544.68.228.0/2344.68.228.1 to 44.68.229.25444.68.229.255510
11644.68.230.0/2344.68.230.1 to 44.68.231.25444.68.231.255510
11744.68.232.0/2344.68.232.1 to 44.68.233.25444.68.233.255510
11844.68.234.0/2344.68.234.1 to 44.68.235.25444.68.235.255510
11944.68.236.0/2344.68.236.1 to 44.68.237.25444.68.237.255510
12044.68.238.0/2344.68.238.1 to 44.68.239.25444.68.239.255510
12144.68.240.0/2344.68.240.1 to 44.68.241.25444.68.241.255510
12244.68.242.0/2344.68.242.1 to 44.68.243.25444.68.243.255510
12344.68.244.0/2344.68.244.1 to 44.68.245.25444.68.245.255510
12444.68.246.0/2344.68.246.1 to 44.68.247.25444.68.247.255510
12544.68.248.0/2344.68.248.1 to 44.68.249.25444.68.249.255510
12644.68.250.0/2344.68.250.1 to 44.68.251.25444.68.251.255510
12744.68.252.0/2344.68.252.1 to 44.68.253.25444.68.253.255510
12844.68.254.0/2344.68.254.1 to 44.68.255.25444.68.255.255510
12944.69.0.0/2344.69.0.1 to 44.69.1.25444.69.1.255510
13044.69.2.0/2344.69.2.1 to 44.69.3.25444.69.3.255510
13144.69.4.0/2344.69.4.1 to 44.69.5.25444.69.5.255510
13244.69.6.0/2344.69.6.1 to 44.69.7.25444.69.7.255510
13344.69.8.0/2344.69.8.1 to 44.69.9.25444.69.9.255510
13444.69.10.0/2344.69.10.1 to 44.69.11.25444.69.11.255510
13544.69.12.0/2344.69.12.1 to 44.69.13.25444.69.13.255510
13644.69.14.0/2344.69.14.1 to 44.69.15.25444.69.15.255510
13744.69.16.0/2344.69.16.1 to 44.69.17.25444.69.17.255510
13844.69.18.0/2344.69.18.1 to 44.69.19.25444.69.19.255510
13944.69.20.0/2344.69.20.1 to 44.69.21.25444.69.21.255510
14044.69.22.0/2344.69.22.1 to 44.69.23.25444.69.23.255510
14144.69.24.0/2344.69.24.1 to 44.69.25.25444.69.25.255510
14244.69.26.0/2344.69.26.1 to 44.69.27.25444.69.27.255510
14344.69.28.0/2344.69.28.1 to 44.69.29.25444.69.29.255510
14444.69.30.0/2344.69.30.1 to 44.69.31.25444.69.31.255510
14544.69.32.0/2344.69.32.1 to 44.69.33.25444.69.33.255510
14644.69.34.0/2344.69.34.1 to 44.69.35.25444.69.35.255510
14744.69.36.0/2344.69.36.1 to 44.69.37.25444.69.37.255510
14844.69.38.0/2344.69.38.1 to 44.69.39.25444.69.39.255510
14944.69.40.0/2344.69.40.1 to 44.69.41.25444.69.41.255510
15044.69.42.0/2344.69.42.1 to 44.69.43.25444.69.43.255510
15144.69.44.0/2344.69.44.1 to 44.69.45.25444.69.45.255510
15244.69.46.0/2344.69.46.1 to 44.69.47.25444.69.47.255510
15344.69.48.0/2344.69.48.1 to 44.69.49.25444.69.49.255510
15444.69.50.0/2344.69.50.1 to 44.69.51.25444.69.51.255510
15544.69.52.0/2344.69.52.1 to 44.69.53.25444.69.53.255510
15644.69.54.0/2344.69.54.1 to 44.69.55.25444.69.55.255510
15744.69.56.0/2344.69.56.1 to 44.69.57.25444.69.57.255510
15844.69.58.0/2344.69.58.1 to 44.69.59.25444.69.59.255510
15944.69.60.0/2344.69.60.1 to 44.69.61.25444.69.61.255510
16044.69.62.0/2344.69.62.1 to 44.69.63.25444.69.63.255510
16144.69.64.0/2344.69.64.1 to 44.69.65.25444.69.65.255510
16244.69.66.0/2344.69.66.1 to 44.69.67.25444.69.67.255510
16344.69.68.0/2344.69.68.1 to 44.69.69.25444.69.69.255510
16444.69.70.0/2344.69.70.1 to 44.69.71.25444.69.71.255510
16544.69.72.0/2344.69.72.1 to 44.69.73.25444.69.73.255510
16644.69.74.0/2344.69.74.1 to 44.69.75.25444.69.75.255510
16744.69.76.0/2344.69.76.1 to 44.69.77.25444.69.77.255510
16844.69.78.0/2344.69.78.1 to 44.69.79.25444.69.79.255510
16944.69.80.0/2344.69.80.1 to 44.69.81.25444.69.81.255510
17044.69.82.0/2344.69.82.1 to 44.69.83.25444.69.83.255510
17144.69.84.0/2344.69.84.1 to 44.69.85.25444.69.85.255510
17244.69.86.0/2344.69.86.1 to 44.69.87.25444.69.87.255510
17344.69.88.0/2344.69.88.1 to 44.69.89.25444.69.89.255510
17444.69.90.0/2344.69.90.1 to 44.69.91.25444.69.91.255510
17544.69.92.0/2344.69.92.1 to 44.69.93.25444.69.93.255510
17644.69.94.0/2344.69.94.1 to 44.69.95.25444.69.95.255510
17744.69.96.0/2344.69.96.1 to 44.69.97.25444.69.97.255510
17844.69.98.0/2344.69.98.1 to 44.69.99.25444.69.99.255510
17944.69.100.0/2344.69.100.1 to 44.69.101.25444.69.101.255510
18044.69.102.0/2344.69.102.1 to 44.69.103.25444.69.103.255510
18144.69.104.0/2344.69.104.1 to 44.69.105.25444.69.105.255510
18244.69.106.0/2344.69.106.1 to 44.69.107.25444.69.107.255510
18344.69.108.0/2344.69.108.1 to 44.69.109.25444.69.109.255510
18444.69.110.0/2344.69.110.1 to 44.69.111.25444.69.111.255510
18544.69.112.0/2344.69.112.1 to 44.69.113.25444.69.113.255510
18644.69.114.0/2344.69.114.1 to 44.69.115.25444.69.115.255510
18744.69.116.0/2344.69.116.1 to 44.69.117.25444.69.117.255510
18844.69.118.0/2344.69.118.1 to 44.69.119.25444.69.119.255510
18944.69.120.0/2344.69.120.1 to 44.69.121.25444.69.121.255510
19044.69.122.0/2344.69.122.1 to 44.69.123.25444.69.123.255510
19144.69.124.0/2344.69.124.1 to 44.69.125.25444.69.125.255510
19244.69.126.0/2344.69.126.1 to 44.69.127.25444.69.127.255510
19344.69.128.0/2344.69.128.1 to 44.69.129.25444.69.129.255510
19444.69.130.0/2344.69.130.1 to 44.69.131.25444.69.131.255510
19544.69.132.0/2344.69.132.1 to 44.69.133.25444.69.133.255510
19644.69.134.0/2344.69.134.1 to 44.69.135.25444.69.135.255510
19744.69.136.0/2344.69.136.1 to 44.69.137.25444.69.137.255510
19844.69.138.0/2344.69.138.1 to 44.69.139.25444.69.139.255510
19944.69.140.0/2344.69.140.1 to 44.69.141.25444.69.141.255510
20044.69.142.0/2344.69.142.1 to 44.69.143.25444.69.143.255510
20144.69.144.0/2344.69.144.1 to 44.69.145.25444.69.145.255510
20244.69.146.0/2344.69.146.1 to 44.69.147.25444.69.147.255510
20344.69.148.0/2344.69.148.1 to 44.69.149.25444.69.149.255510
20444.69.150.0/2344.69.150.1 to 44.69.151.25444.69.151.255510
20544.69.152.0/2344.69.152.1 to 44.69.153.25444.69.153.255510
20644.69.154.0/2344.69.154.1 to 44.69.155.25444.69.155.255510
20744.69.156.0/2344.69.156.1 to 44.69.157.25444.69.157.255510
20844.69.158.0/2344.69.158.1 to 44.69.159.25444.69.159.255510
20944.69.160.0/2344.69.160.1 to 44.69.161.25444.69.161.255510
21044.69.162.0/2344.69.162.1 to 44.69.163.25444.69.163.255510
21144.69.164.0/2344.69.164.1 to 44.69.165.25444.69.165.255510
21244.69.166.0/2344.69.166.1 to 44.69.167.25444.69.167.255510
21344.69.168.0/2344.69.168.1 to 44.69.169.25444.69.169.255510
21444.69.170.0/2344.69.170.1 to 44.69.171.25444.69.171.255510
21544.69.172.0/2344.69.172.1 to 44.69.173.25444.69.173.255510
21644.69.174.0/2344.69.174.1 to 44.69.175.25444.69.175.255510
21744.69.176.0/2344.69.176.1 to 44.69.177.25444.69.177.255510
21844.69.178.0/2344.69.178.1 to 44.69.179.25444.69.179.255510
21944.69.180.0/2344.69.180.1 to 44.69.181.25444.69.181.255510
22044.69.182.0/2344.69.182.1 to 44.69.183.25444.69.183.255510
22144.69.184.0/2344.69.184.1 to 44.69.185.25444.69.185.255510
22244.69.186.0/2344.69.186.1 to 44.69.187.25444.69.187.255510
22344.69.188.0/2344.69.188.1 to 44.69.189.25444.69.189.255510
22444.69.190.0/2344.69.190.1 to 44.69.191.25444.69.191.255510
22544.69.192.0/2344.69.192.1 to 44.69.193.25444.69.193.255510
22644.69.194.0/2344.69.194.1 to 44.69.195.25444.69.195.255510
22744.69.196.0/2344.69.196.1 to 44.69.197.25444.69.197.255510
22844.69.198.0/2344.69.198.1 to 44.69.199.25444.69.199.255510
22944.69.200.0/2344.69.200.1 to 44.69.201.25444.69.201.255510
23044.69.202.0/2344.69.202.1 to 44.69.203.25444.69.203.255510
23144.69.204.0/2344.69.204.1 to 44.69.205.25444.69.205.255510
23244.69.206.0/2344.69.206.1 to 44.69.207.25444.69.207.255510
23344.69.208.0/2344.69.208.1 to 44.69.209.25444.69.209.255510
23444.69.210.0/2344.69.210.1 to 44.69.211.25444.69.211.255510
23544.69.212.0/2344.69.212.1 to 44.69.213.25444.69.213.255510
23644.69.214.0/2344.69.214.1 to 44.69.215.25444.69.215.255510
23744.69.216.0/2344.69.216.1 to 44.69.217.25444.69.217.255510
23844.69.218.0/2344.69.218.1 to 44.69.219.25444.69.219.255510
23944.69.220.0/2344.69.220.1 to 44.69.221.25444.69.221.255510
24044.69.222.0/2344.69.222.1 to 44.69.223.25444.69.223.255510
24144.69.224.0/2344.69.224.1 to 44.69.225.25444.69.225.255510
24244.69.226.0/2344.69.226.1 to 44.69.227.25444.69.227.255510
24344.69.228.0/2344.69.228.1 to 44.69.229.25444.69.229.255510
24444.69.230.0/2344.69.230.1 to 44.69.231.25444.69.231.255510
24544.69.232.0/2344.69.232.1 to 44.69.233.25444.69.233.255510
24644.69.234.0/2344.69.234.1 to 44.69.235.25444.69.235.255510
24744.69.236.0/2344.69.236.1 to 44.69.237.25444.69.237.255510
24844.69.238.0/2344.69.238.1 to 44.69.239.25444.69.239.255510
24944.69.240.0/2344.69.240.1 to 44.69.241.25444.69.241.255510
25044.69.242.0/2344.69.242.1 to 44.69.243.25444.69.243.255510
25144.69.244.0/2344.69.244.1 to 44.69.245.25444.69.245.255510
25244.69.246.0/2344.69.246.1 to 44.69.247.25444.69.247.255510
25344.69.248.0/2344.69.248.1 to 44.69.249.25444.69.249.255510
25444.69.250.0/2344.69.250.1 to 44.69.251.25444.69.251.255510
25544.69.252.0/2344.69.252.1 to 44.69.253.25444.69.253.255510
25644.69.254.0/2344.69.254.1 to 44.69.255.25444.69.255.255510

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.