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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.

Network29.224.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
29.224.0.0
Broadcast address
29.255.255.255
First usable
29.224.0.1
Last usable
29.255.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Public public
Old class
A (default /8)
As numbers
Hex 1DE00000 · Integer 501219328 to 503316479
Reverse DNS zones
224.29.in-addr.arpa
225.29.in-addr.arpa
226.29.in-addr.arpa
227.29.in-addr.arpa
228.29.in-addr.arpa
229.29.in-addr.arpa
230.29.in-addr.arpa
231.29.in-addr.arpa
232.29.in-addr.arpa
233.29.in-addr.arpa
234.29.in-addr.arpa
235.29.in-addr.arpa
236.29.in-addr.arpa
237.29.in-addr.arpa
238.29.in-addr.arpa
239.29.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00011101.11100000.00000000.0000000029.224.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network00011101.11100000.00000000.0000000029.224.0.0
Broadcast00011101.11111111.11111111.1111111129.255.255.255
Split into smaller subnets/23
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

29.224.0.0/11 makes 4,096 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
129.224.0.0/2329.224.0.1 to 29.224.1.25429.224.1.255510
229.224.2.0/2329.224.2.1 to 29.224.3.25429.224.3.255510
329.224.4.0/2329.224.4.1 to 29.224.5.25429.224.5.255510
429.224.6.0/2329.224.6.1 to 29.224.7.25429.224.7.255510
529.224.8.0/2329.224.8.1 to 29.224.9.25429.224.9.255510
629.224.10.0/2329.224.10.1 to 29.224.11.25429.224.11.255510
729.224.12.0/2329.224.12.1 to 29.224.13.25429.224.13.255510
829.224.14.0/2329.224.14.1 to 29.224.15.25429.224.15.255510
929.224.16.0/2329.224.16.1 to 29.224.17.25429.224.17.255510
1029.224.18.0/2329.224.18.1 to 29.224.19.25429.224.19.255510
1129.224.20.0/2329.224.20.1 to 29.224.21.25429.224.21.255510
1229.224.22.0/2329.224.22.1 to 29.224.23.25429.224.23.255510
1329.224.24.0/2329.224.24.1 to 29.224.25.25429.224.25.255510
1429.224.26.0/2329.224.26.1 to 29.224.27.25429.224.27.255510
1529.224.28.0/2329.224.28.1 to 29.224.29.25429.224.29.255510
1629.224.30.0/2329.224.30.1 to 29.224.31.25429.224.31.255510
1729.224.32.0/2329.224.32.1 to 29.224.33.25429.224.33.255510
1829.224.34.0/2329.224.34.1 to 29.224.35.25429.224.35.255510
1929.224.36.0/2329.224.36.1 to 29.224.37.25429.224.37.255510
2029.224.38.0/2329.224.38.1 to 29.224.39.25429.224.39.255510
2129.224.40.0/2329.224.40.1 to 29.224.41.25429.224.41.255510
2229.224.42.0/2329.224.42.1 to 29.224.43.25429.224.43.255510
2329.224.44.0/2329.224.44.1 to 29.224.45.25429.224.45.255510
2429.224.46.0/2329.224.46.1 to 29.224.47.25429.224.47.255510
2529.224.48.0/2329.224.48.1 to 29.224.49.25429.224.49.255510
2629.224.50.0/2329.224.50.1 to 29.224.51.25429.224.51.255510
2729.224.52.0/2329.224.52.1 to 29.224.53.25429.224.53.255510
2829.224.54.0/2329.224.54.1 to 29.224.55.25429.224.55.255510
2929.224.56.0/2329.224.56.1 to 29.224.57.25429.224.57.255510
3029.224.58.0/2329.224.58.1 to 29.224.59.25429.224.59.255510
3129.224.60.0/2329.224.60.1 to 29.224.61.25429.224.61.255510
3229.224.62.0/2329.224.62.1 to 29.224.63.25429.224.63.255510
3329.224.64.0/2329.224.64.1 to 29.224.65.25429.224.65.255510
3429.224.66.0/2329.224.66.1 to 29.224.67.25429.224.67.255510
3529.224.68.0/2329.224.68.1 to 29.224.69.25429.224.69.255510
3629.224.70.0/2329.224.70.1 to 29.224.71.25429.224.71.255510
3729.224.72.0/2329.224.72.1 to 29.224.73.25429.224.73.255510
3829.224.74.0/2329.224.74.1 to 29.224.75.25429.224.75.255510
3929.224.76.0/2329.224.76.1 to 29.224.77.25429.224.77.255510
4029.224.78.0/2329.224.78.1 to 29.224.79.25429.224.79.255510
4129.224.80.0/2329.224.80.1 to 29.224.81.25429.224.81.255510
4229.224.82.0/2329.224.82.1 to 29.224.83.25429.224.83.255510
4329.224.84.0/2329.224.84.1 to 29.224.85.25429.224.85.255510
4429.224.86.0/2329.224.86.1 to 29.224.87.25429.224.87.255510
4529.224.88.0/2329.224.88.1 to 29.224.89.25429.224.89.255510
4629.224.90.0/2329.224.90.1 to 29.224.91.25429.224.91.255510
4729.224.92.0/2329.224.92.1 to 29.224.93.25429.224.93.255510
4829.224.94.0/2329.224.94.1 to 29.224.95.25429.224.95.255510
4929.224.96.0/2329.224.96.1 to 29.224.97.25429.224.97.255510
5029.224.98.0/2329.224.98.1 to 29.224.99.25429.224.99.255510
5129.224.100.0/2329.224.100.1 to 29.224.101.25429.224.101.255510
5229.224.102.0/2329.224.102.1 to 29.224.103.25429.224.103.255510
5329.224.104.0/2329.224.104.1 to 29.224.105.25429.224.105.255510
5429.224.106.0/2329.224.106.1 to 29.224.107.25429.224.107.255510
5529.224.108.0/2329.224.108.1 to 29.224.109.25429.224.109.255510
5629.224.110.0/2329.224.110.1 to 29.224.111.25429.224.111.255510
5729.224.112.0/2329.224.112.1 to 29.224.113.25429.224.113.255510
5829.224.114.0/2329.224.114.1 to 29.224.115.25429.224.115.255510
5929.224.116.0/2329.224.116.1 to 29.224.117.25429.224.117.255510
6029.224.118.0/2329.224.118.1 to 29.224.119.25429.224.119.255510
6129.224.120.0/2329.224.120.1 to 29.224.121.25429.224.121.255510
6229.224.122.0/2329.224.122.1 to 29.224.123.25429.224.123.255510
6329.224.124.0/2329.224.124.1 to 29.224.125.25429.224.125.255510
6429.224.126.0/2329.224.126.1 to 29.224.127.25429.224.127.255510
6529.224.128.0/2329.224.128.1 to 29.224.129.25429.224.129.255510
6629.224.130.0/2329.224.130.1 to 29.224.131.25429.224.131.255510
6729.224.132.0/2329.224.132.1 to 29.224.133.25429.224.133.255510
6829.224.134.0/2329.224.134.1 to 29.224.135.25429.224.135.255510
6929.224.136.0/2329.224.136.1 to 29.224.137.25429.224.137.255510
7029.224.138.0/2329.224.138.1 to 29.224.139.25429.224.139.255510
7129.224.140.0/2329.224.140.1 to 29.224.141.25429.224.141.255510
7229.224.142.0/2329.224.142.1 to 29.224.143.25429.224.143.255510
7329.224.144.0/2329.224.144.1 to 29.224.145.25429.224.145.255510
7429.224.146.0/2329.224.146.1 to 29.224.147.25429.224.147.255510
7529.224.148.0/2329.224.148.1 to 29.224.149.25429.224.149.255510
7629.224.150.0/2329.224.150.1 to 29.224.151.25429.224.151.255510
7729.224.152.0/2329.224.152.1 to 29.224.153.25429.224.153.255510
7829.224.154.0/2329.224.154.1 to 29.224.155.25429.224.155.255510
7929.224.156.0/2329.224.156.1 to 29.224.157.25429.224.157.255510
8029.224.158.0/2329.224.158.1 to 29.224.159.25429.224.159.255510
8129.224.160.0/2329.224.160.1 to 29.224.161.25429.224.161.255510
8229.224.162.0/2329.224.162.1 to 29.224.163.25429.224.163.255510
8329.224.164.0/2329.224.164.1 to 29.224.165.25429.224.165.255510
8429.224.166.0/2329.224.166.1 to 29.224.167.25429.224.167.255510
8529.224.168.0/2329.224.168.1 to 29.224.169.25429.224.169.255510
8629.224.170.0/2329.224.170.1 to 29.224.171.25429.224.171.255510
8729.224.172.0/2329.224.172.1 to 29.224.173.25429.224.173.255510
8829.224.174.0/2329.224.174.1 to 29.224.175.25429.224.175.255510
8929.224.176.0/2329.224.176.1 to 29.224.177.25429.224.177.255510
9029.224.178.0/2329.224.178.1 to 29.224.179.25429.224.179.255510
9129.224.180.0/2329.224.180.1 to 29.224.181.25429.224.181.255510
9229.224.182.0/2329.224.182.1 to 29.224.183.25429.224.183.255510
9329.224.184.0/2329.224.184.1 to 29.224.185.25429.224.185.255510
9429.224.186.0/2329.224.186.1 to 29.224.187.25429.224.187.255510
9529.224.188.0/2329.224.188.1 to 29.224.189.25429.224.189.255510
9629.224.190.0/2329.224.190.1 to 29.224.191.25429.224.191.255510
9729.224.192.0/2329.224.192.1 to 29.224.193.25429.224.193.255510
9829.224.194.0/2329.224.194.1 to 29.224.195.25429.224.195.255510
9929.224.196.0/2329.224.196.1 to 29.224.197.25429.224.197.255510
10029.224.198.0/2329.224.198.1 to 29.224.199.25429.224.199.255510
10129.224.200.0/2329.224.200.1 to 29.224.201.25429.224.201.255510
10229.224.202.0/2329.224.202.1 to 29.224.203.25429.224.203.255510
10329.224.204.0/2329.224.204.1 to 29.224.205.25429.224.205.255510
10429.224.206.0/2329.224.206.1 to 29.224.207.25429.224.207.255510
10529.224.208.0/2329.224.208.1 to 29.224.209.25429.224.209.255510
10629.224.210.0/2329.224.210.1 to 29.224.211.25429.224.211.255510
10729.224.212.0/2329.224.212.1 to 29.224.213.25429.224.213.255510
10829.224.214.0/2329.224.214.1 to 29.224.215.25429.224.215.255510
10929.224.216.0/2329.224.216.1 to 29.224.217.25429.224.217.255510
11029.224.218.0/2329.224.218.1 to 29.224.219.25429.224.219.255510
11129.224.220.0/2329.224.220.1 to 29.224.221.25429.224.221.255510
11229.224.222.0/2329.224.222.1 to 29.224.223.25429.224.223.255510
11329.224.224.0/2329.224.224.1 to 29.224.225.25429.224.225.255510
11429.224.226.0/2329.224.226.1 to 29.224.227.25429.224.227.255510
11529.224.228.0/2329.224.228.1 to 29.224.229.25429.224.229.255510
11629.224.230.0/2329.224.230.1 to 29.224.231.25429.224.231.255510
11729.224.232.0/2329.224.232.1 to 29.224.233.25429.224.233.255510
11829.224.234.0/2329.224.234.1 to 29.224.235.25429.224.235.255510
11929.224.236.0/2329.224.236.1 to 29.224.237.25429.224.237.255510
12029.224.238.0/2329.224.238.1 to 29.224.239.25429.224.239.255510
12129.224.240.0/2329.224.240.1 to 29.224.241.25429.224.241.255510
12229.224.242.0/2329.224.242.1 to 29.224.243.25429.224.243.255510
12329.224.244.0/2329.224.244.1 to 29.224.245.25429.224.245.255510
12429.224.246.0/2329.224.246.1 to 29.224.247.25429.224.247.255510
12529.224.248.0/2329.224.248.1 to 29.224.249.25429.224.249.255510
12629.224.250.0/2329.224.250.1 to 29.224.251.25429.224.251.255510
12729.224.252.0/2329.224.252.1 to 29.224.253.25429.224.253.255510
12829.224.254.0/2329.224.254.1 to 29.224.255.25429.224.255.255510
12929.225.0.0/2329.225.0.1 to 29.225.1.25429.225.1.255510
13029.225.2.0/2329.225.2.1 to 29.225.3.25429.225.3.255510
13129.225.4.0/2329.225.4.1 to 29.225.5.25429.225.5.255510
13229.225.6.0/2329.225.6.1 to 29.225.7.25429.225.7.255510
13329.225.8.0/2329.225.8.1 to 29.225.9.25429.225.9.255510
13429.225.10.0/2329.225.10.1 to 29.225.11.25429.225.11.255510
13529.225.12.0/2329.225.12.1 to 29.225.13.25429.225.13.255510
13629.225.14.0/2329.225.14.1 to 29.225.15.25429.225.15.255510
13729.225.16.0/2329.225.16.1 to 29.225.17.25429.225.17.255510
13829.225.18.0/2329.225.18.1 to 29.225.19.25429.225.19.255510
13929.225.20.0/2329.225.20.1 to 29.225.21.25429.225.21.255510
14029.225.22.0/2329.225.22.1 to 29.225.23.25429.225.23.255510
14129.225.24.0/2329.225.24.1 to 29.225.25.25429.225.25.255510
14229.225.26.0/2329.225.26.1 to 29.225.27.25429.225.27.255510
14329.225.28.0/2329.225.28.1 to 29.225.29.25429.225.29.255510
14429.225.30.0/2329.225.30.1 to 29.225.31.25429.225.31.255510
14529.225.32.0/2329.225.32.1 to 29.225.33.25429.225.33.255510
14629.225.34.0/2329.225.34.1 to 29.225.35.25429.225.35.255510
14729.225.36.0/2329.225.36.1 to 29.225.37.25429.225.37.255510
14829.225.38.0/2329.225.38.1 to 29.225.39.25429.225.39.255510
14929.225.40.0/2329.225.40.1 to 29.225.41.25429.225.41.255510
15029.225.42.0/2329.225.42.1 to 29.225.43.25429.225.43.255510
15129.225.44.0/2329.225.44.1 to 29.225.45.25429.225.45.255510
15229.225.46.0/2329.225.46.1 to 29.225.47.25429.225.47.255510
15329.225.48.0/2329.225.48.1 to 29.225.49.25429.225.49.255510
15429.225.50.0/2329.225.50.1 to 29.225.51.25429.225.51.255510
15529.225.52.0/2329.225.52.1 to 29.225.53.25429.225.53.255510
15629.225.54.0/2329.225.54.1 to 29.225.55.25429.225.55.255510
15729.225.56.0/2329.225.56.1 to 29.225.57.25429.225.57.255510
15829.225.58.0/2329.225.58.1 to 29.225.59.25429.225.59.255510
15929.225.60.0/2329.225.60.1 to 29.225.61.25429.225.61.255510
16029.225.62.0/2329.225.62.1 to 29.225.63.25429.225.63.255510
16129.225.64.0/2329.225.64.1 to 29.225.65.25429.225.65.255510
16229.225.66.0/2329.225.66.1 to 29.225.67.25429.225.67.255510
16329.225.68.0/2329.225.68.1 to 29.225.69.25429.225.69.255510
16429.225.70.0/2329.225.70.1 to 29.225.71.25429.225.71.255510
16529.225.72.0/2329.225.72.1 to 29.225.73.25429.225.73.255510
16629.225.74.0/2329.225.74.1 to 29.225.75.25429.225.75.255510
16729.225.76.0/2329.225.76.1 to 29.225.77.25429.225.77.255510
16829.225.78.0/2329.225.78.1 to 29.225.79.25429.225.79.255510
16929.225.80.0/2329.225.80.1 to 29.225.81.25429.225.81.255510
17029.225.82.0/2329.225.82.1 to 29.225.83.25429.225.83.255510
17129.225.84.0/2329.225.84.1 to 29.225.85.25429.225.85.255510
17229.225.86.0/2329.225.86.1 to 29.225.87.25429.225.87.255510
17329.225.88.0/2329.225.88.1 to 29.225.89.25429.225.89.255510
17429.225.90.0/2329.225.90.1 to 29.225.91.25429.225.91.255510
17529.225.92.0/2329.225.92.1 to 29.225.93.25429.225.93.255510
17629.225.94.0/2329.225.94.1 to 29.225.95.25429.225.95.255510
17729.225.96.0/2329.225.96.1 to 29.225.97.25429.225.97.255510
17829.225.98.0/2329.225.98.1 to 29.225.99.25429.225.99.255510
17929.225.100.0/2329.225.100.1 to 29.225.101.25429.225.101.255510
18029.225.102.0/2329.225.102.1 to 29.225.103.25429.225.103.255510
18129.225.104.0/2329.225.104.1 to 29.225.105.25429.225.105.255510
18229.225.106.0/2329.225.106.1 to 29.225.107.25429.225.107.255510
18329.225.108.0/2329.225.108.1 to 29.225.109.25429.225.109.255510
18429.225.110.0/2329.225.110.1 to 29.225.111.25429.225.111.255510
18529.225.112.0/2329.225.112.1 to 29.225.113.25429.225.113.255510
18629.225.114.0/2329.225.114.1 to 29.225.115.25429.225.115.255510
18729.225.116.0/2329.225.116.1 to 29.225.117.25429.225.117.255510
18829.225.118.0/2329.225.118.1 to 29.225.119.25429.225.119.255510
18929.225.120.0/2329.225.120.1 to 29.225.121.25429.225.121.255510
19029.225.122.0/2329.225.122.1 to 29.225.123.25429.225.123.255510
19129.225.124.0/2329.225.124.1 to 29.225.125.25429.225.125.255510
19229.225.126.0/2329.225.126.1 to 29.225.127.25429.225.127.255510
19329.225.128.0/2329.225.128.1 to 29.225.129.25429.225.129.255510
19429.225.130.0/2329.225.130.1 to 29.225.131.25429.225.131.255510
19529.225.132.0/2329.225.132.1 to 29.225.133.25429.225.133.255510
19629.225.134.0/2329.225.134.1 to 29.225.135.25429.225.135.255510
19729.225.136.0/2329.225.136.1 to 29.225.137.25429.225.137.255510
19829.225.138.0/2329.225.138.1 to 29.225.139.25429.225.139.255510
19929.225.140.0/2329.225.140.1 to 29.225.141.25429.225.141.255510
20029.225.142.0/2329.225.142.1 to 29.225.143.25429.225.143.255510
20129.225.144.0/2329.225.144.1 to 29.225.145.25429.225.145.255510
20229.225.146.0/2329.225.146.1 to 29.225.147.25429.225.147.255510
20329.225.148.0/2329.225.148.1 to 29.225.149.25429.225.149.255510
20429.225.150.0/2329.225.150.1 to 29.225.151.25429.225.151.255510
20529.225.152.0/2329.225.152.1 to 29.225.153.25429.225.153.255510
20629.225.154.0/2329.225.154.1 to 29.225.155.25429.225.155.255510
20729.225.156.0/2329.225.156.1 to 29.225.157.25429.225.157.255510
20829.225.158.0/2329.225.158.1 to 29.225.159.25429.225.159.255510
20929.225.160.0/2329.225.160.1 to 29.225.161.25429.225.161.255510
21029.225.162.0/2329.225.162.1 to 29.225.163.25429.225.163.255510
21129.225.164.0/2329.225.164.1 to 29.225.165.25429.225.165.255510
21229.225.166.0/2329.225.166.1 to 29.225.167.25429.225.167.255510
21329.225.168.0/2329.225.168.1 to 29.225.169.25429.225.169.255510
21429.225.170.0/2329.225.170.1 to 29.225.171.25429.225.171.255510
21529.225.172.0/2329.225.172.1 to 29.225.173.25429.225.173.255510
21629.225.174.0/2329.225.174.1 to 29.225.175.25429.225.175.255510
21729.225.176.0/2329.225.176.1 to 29.225.177.25429.225.177.255510
21829.225.178.0/2329.225.178.1 to 29.225.179.25429.225.179.255510
21929.225.180.0/2329.225.180.1 to 29.225.181.25429.225.181.255510
22029.225.182.0/2329.225.182.1 to 29.225.183.25429.225.183.255510
22129.225.184.0/2329.225.184.1 to 29.225.185.25429.225.185.255510
22229.225.186.0/2329.225.186.1 to 29.225.187.25429.225.187.255510
22329.225.188.0/2329.225.188.1 to 29.225.189.25429.225.189.255510
22429.225.190.0/2329.225.190.1 to 29.225.191.25429.225.191.255510
22529.225.192.0/2329.225.192.1 to 29.225.193.25429.225.193.255510
22629.225.194.0/2329.225.194.1 to 29.225.195.25429.225.195.255510
22729.225.196.0/2329.225.196.1 to 29.225.197.25429.225.197.255510
22829.225.198.0/2329.225.198.1 to 29.225.199.25429.225.199.255510
22929.225.200.0/2329.225.200.1 to 29.225.201.25429.225.201.255510
23029.225.202.0/2329.225.202.1 to 29.225.203.25429.225.203.255510
23129.225.204.0/2329.225.204.1 to 29.225.205.25429.225.205.255510
23229.225.206.0/2329.225.206.1 to 29.225.207.25429.225.207.255510
23329.225.208.0/2329.225.208.1 to 29.225.209.25429.225.209.255510
23429.225.210.0/2329.225.210.1 to 29.225.211.25429.225.211.255510
23529.225.212.0/2329.225.212.1 to 29.225.213.25429.225.213.255510
23629.225.214.0/2329.225.214.1 to 29.225.215.25429.225.215.255510
23729.225.216.0/2329.225.216.1 to 29.225.217.25429.225.217.255510
23829.225.218.0/2329.225.218.1 to 29.225.219.25429.225.219.255510
23929.225.220.0/2329.225.220.1 to 29.225.221.25429.225.221.255510
24029.225.222.0/2329.225.222.1 to 29.225.223.25429.225.223.255510
24129.225.224.0/2329.225.224.1 to 29.225.225.25429.225.225.255510
24229.225.226.0/2329.225.226.1 to 29.225.227.25429.225.227.255510
24329.225.228.0/2329.225.228.1 to 29.225.229.25429.225.229.255510
24429.225.230.0/2329.225.230.1 to 29.225.231.25429.225.231.255510
24529.225.232.0/2329.225.232.1 to 29.225.233.25429.225.233.255510
24629.225.234.0/2329.225.234.1 to 29.225.235.25429.225.235.255510
24729.225.236.0/2329.225.236.1 to 29.225.237.25429.225.237.255510
24829.225.238.0/2329.225.238.1 to 29.225.239.25429.225.239.255510
24929.225.240.0/2329.225.240.1 to 29.225.241.25429.225.241.255510
25029.225.242.0/2329.225.242.1 to 29.225.243.25429.225.243.255510
25129.225.244.0/2329.225.244.1 to 29.225.245.25429.225.245.255510
25229.225.246.0/2329.225.246.1 to 29.225.247.25429.225.247.255510
25329.225.248.0/2329.225.248.1 to 29.225.249.25429.225.249.255510
25429.225.250.0/2329.225.250.1 to 29.225.251.25429.225.251.255510
25529.225.252.0/2329.225.252.1 to 29.225.253.25429.225.253.255510
25629.225.254.0/2329.225.254.1 to 29.225.255.25429.225.255.255510

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.