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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.

Network88.0.0.0/5
Usable hosts134,217,726
Subnet mask248.0.0.0
Addresses134,217,728
Network address
88.0.0.0
Broadcast address
95.255.255.255
First usable
88.0.0.1
Last usable
95.255.255.254
Usable hosts
134,217,726 (134,217,728 less the network and broadcast addresses)
Subnet mask
248.0.0.0
Wildcard mask
7.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/5
Type
Public public
Old class
A (default /8)
As numbers
Hex 58000000 · Integer 1476395008 to 1610612735
Reverse DNS zones
88.in-addr.arpa
89.in-addr.arpa
90.in-addr.arpa
91.in-addr.arpa
92.in-addr.arpa
93.in-addr.arpa
94.in-addr.arpa
95.in-addr.arpa
/5 is not on a 8-bit boundary, so it takes 8 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011000.00000000.00000000.0000000088.0.0.0
Subnet mask11111000.00000000.00000000.00000000248.0.0.0
Network01011000.00000000.00000000.0000000088.0.0.0
Broadcast01011111.11111111.11111111.1111111195.255.255.255
Split into smaller subnets/16
/6 (2)/7 (4)/8 (8)/9 (16)/10 (32)/11 (64)/12 (128)/13 (256)/14 (512)/15 (1,024)/16 (2,048)/17 (4,096)

88.0.0.0/5 makes 2,048 subnets of /16; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
188.0.0.0/1688.0.0.1 to 88.0.255.25488.0.255.25565,534
288.1.0.0/1688.1.0.1 to 88.1.255.25488.1.255.25565,534
388.2.0.0/1688.2.0.1 to 88.2.255.25488.2.255.25565,534
488.3.0.0/1688.3.0.1 to 88.3.255.25488.3.255.25565,534
588.4.0.0/1688.4.0.1 to 88.4.255.25488.4.255.25565,534
688.5.0.0/1688.5.0.1 to 88.5.255.25488.5.255.25565,534
788.6.0.0/1688.6.0.1 to 88.6.255.25488.6.255.25565,534
888.7.0.0/1688.7.0.1 to 88.7.255.25488.7.255.25565,534
988.8.0.0/1688.8.0.1 to 88.8.255.25488.8.255.25565,534
1088.9.0.0/1688.9.0.1 to 88.9.255.25488.9.255.25565,534
1188.10.0.0/1688.10.0.1 to 88.10.255.25488.10.255.25565,534
1288.11.0.0/1688.11.0.1 to 88.11.255.25488.11.255.25565,534
1388.12.0.0/1688.12.0.1 to 88.12.255.25488.12.255.25565,534
1488.13.0.0/1688.13.0.1 to 88.13.255.25488.13.255.25565,534
1588.14.0.0/1688.14.0.1 to 88.14.255.25488.14.255.25565,534
1688.15.0.0/1688.15.0.1 to 88.15.255.25488.15.255.25565,534
1788.16.0.0/1688.16.0.1 to 88.16.255.25488.16.255.25565,534
1888.17.0.0/1688.17.0.1 to 88.17.255.25488.17.255.25565,534
1988.18.0.0/1688.18.0.1 to 88.18.255.25488.18.255.25565,534
2088.19.0.0/1688.19.0.1 to 88.19.255.25488.19.255.25565,534
2188.20.0.0/1688.20.0.1 to 88.20.255.25488.20.255.25565,534
2288.21.0.0/1688.21.0.1 to 88.21.255.25488.21.255.25565,534
2388.22.0.0/1688.22.0.1 to 88.22.255.25488.22.255.25565,534
2488.23.0.0/1688.23.0.1 to 88.23.255.25488.23.255.25565,534
2588.24.0.0/1688.24.0.1 to 88.24.255.25488.24.255.25565,534
2688.25.0.0/1688.25.0.1 to 88.25.255.25488.25.255.25565,534
2788.26.0.0/1688.26.0.1 to 88.26.255.25488.26.255.25565,534
2888.27.0.0/1688.27.0.1 to 88.27.255.25488.27.255.25565,534
2988.28.0.0/1688.28.0.1 to 88.28.255.25488.28.255.25565,534
3088.29.0.0/1688.29.0.1 to 88.29.255.25488.29.255.25565,534
3188.30.0.0/1688.30.0.1 to 88.30.255.25488.30.255.25565,534
3288.31.0.0/1688.31.0.1 to 88.31.255.25488.31.255.25565,534
3388.32.0.0/1688.32.0.1 to 88.32.255.25488.32.255.25565,534
3488.33.0.0/1688.33.0.1 to 88.33.255.25488.33.255.25565,534
3588.34.0.0/1688.34.0.1 to 88.34.255.25488.34.255.25565,534
3688.35.0.0/1688.35.0.1 to 88.35.255.25488.35.255.25565,534
3788.36.0.0/1688.36.0.1 to 88.36.255.25488.36.255.25565,534
3888.37.0.0/1688.37.0.1 to 88.37.255.25488.37.255.25565,534
3988.38.0.0/1688.38.0.1 to 88.38.255.25488.38.255.25565,534
4088.39.0.0/1688.39.0.1 to 88.39.255.25488.39.255.25565,534
4188.40.0.0/1688.40.0.1 to 88.40.255.25488.40.255.25565,534
4288.41.0.0/1688.41.0.1 to 88.41.255.25488.41.255.25565,534
4388.42.0.0/1688.42.0.1 to 88.42.255.25488.42.255.25565,534
4488.43.0.0/1688.43.0.1 to 88.43.255.25488.43.255.25565,534
4588.44.0.0/1688.44.0.1 to 88.44.255.25488.44.255.25565,534
4688.45.0.0/1688.45.0.1 to 88.45.255.25488.45.255.25565,534
4788.46.0.0/1688.46.0.1 to 88.46.255.25488.46.255.25565,534
4888.47.0.0/1688.47.0.1 to 88.47.255.25488.47.255.25565,534
4988.48.0.0/1688.48.0.1 to 88.48.255.25488.48.255.25565,534
5088.49.0.0/1688.49.0.1 to 88.49.255.25488.49.255.25565,534
5188.50.0.0/1688.50.0.1 to 88.50.255.25488.50.255.25565,534
5288.51.0.0/1688.51.0.1 to 88.51.255.25488.51.255.25565,534
5388.52.0.0/1688.52.0.1 to 88.52.255.25488.52.255.25565,534
5488.53.0.0/1688.53.0.1 to 88.53.255.25488.53.255.25565,534
5588.54.0.0/1688.54.0.1 to 88.54.255.25488.54.255.25565,534
5688.55.0.0/1688.55.0.1 to 88.55.255.25488.55.255.25565,534
5788.56.0.0/1688.56.0.1 to 88.56.255.25488.56.255.25565,534
5888.57.0.0/1688.57.0.1 to 88.57.255.25488.57.255.25565,534
5988.58.0.0/1688.58.0.1 to 88.58.255.25488.58.255.25565,534
6088.59.0.0/1688.59.0.1 to 88.59.255.25488.59.255.25565,534
6188.60.0.0/1688.60.0.1 to 88.60.255.25488.60.255.25565,534
6288.61.0.0/1688.61.0.1 to 88.61.255.25488.61.255.25565,534
6388.62.0.0/1688.62.0.1 to 88.62.255.25488.62.255.25565,534
6488.63.0.0/1688.63.0.1 to 88.63.255.25488.63.255.25565,534
6588.64.0.0/1688.64.0.1 to 88.64.255.25488.64.255.25565,534
6688.65.0.0/1688.65.0.1 to 88.65.255.25488.65.255.25565,534
6788.66.0.0/1688.66.0.1 to 88.66.255.25488.66.255.25565,534
6888.67.0.0/1688.67.0.1 to 88.67.255.25488.67.255.25565,534
6988.68.0.0/1688.68.0.1 to 88.68.255.25488.68.255.25565,534
7088.69.0.0/1688.69.0.1 to 88.69.255.25488.69.255.25565,534
7188.70.0.0/1688.70.0.1 to 88.70.255.25488.70.255.25565,534
7288.71.0.0/1688.71.0.1 to 88.71.255.25488.71.255.25565,534
7388.72.0.0/1688.72.0.1 to 88.72.255.25488.72.255.25565,534
7488.73.0.0/1688.73.0.1 to 88.73.255.25488.73.255.25565,534
7588.74.0.0/1688.74.0.1 to 88.74.255.25488.74.255.25565,534
7688.75.0.0/1688.75.0.1 to 88.75.255.25488.75.255.25565,534
7788.76.0.0/1688.76.0.1 to 88.76.255.25488.76.255.25565,534
7888.77.0.0/1688.77.0.1 to 88.77.255.25488.77.255.25565,534
7988.78.0.0/1688.78.0.1 to 88.78.255.25488.78.255.25565,534
8088.79.0.0/1688.79.0.1 to 88.79.255.25488.79.255.25565,534
8188.80.0.0/1688.80.0.1 to 88.80.255.25488.80.255.25565,534
8288.81.0.0/1688.81.0.1 to 88.81.255.25488.81.255.25565,534
8388.82.0.0/1688.82.0.1 to 88.82.255.25488.82.255.25565,534
8488.83.0.0/1688.83.0.1 to 88.83.255.25488.83.255.25565,534
8588.84.0.0/1688.84.0.1 to 88.84.255.25488.84.255.25565,534
8688.85.0.0/1688.85.0.1 to 88.85.255.25488.85.255.25565,534
8788.86.0.0/1688.86.0.1 to 88.86.255.25488.86.255.25565,534
8888.87.0.0/1688.87.0.1 to 88.87.255.25488.87.255.25565,534
8988.88.0.0/1688.88.0.1 to 88.88.255.25488.88.255.25565,534
9088.89.0.0/1688.89.0.1 to 88.89.255.25488.89.255.25565,534
9188.90.0.0/1688.90.0.1 to 88.90.255.25488.90.255.25565,534
9288.91.0.0/1688.91.0.1 to 88.91.255.25488.91.255.25565,534
9388.92.0.0/1688.92.0.1 to 88.92.255.25488.92.255.25565,534
9488.93.0.0/1688.93.0.1 to 88.93.255.25488.93.255.25565,534
9588.94.0.0/1688.94.0.1 to 88.94.255.25488.94.255.25565,534
9688.95.0.0/1688.95.0.1 to 88.95.255.25488.95.255.25565,534
9788.96.0.0/1688.96.0.1 to 88.96.255.25488.96.255.25565,534
9888.97.0.0/1688.97.0.1 to 88.97.255.25488.97.255.25565,534
9988.98.0.0/1688.98.0.1 to 88.98.255.25488.98.255.25565,534
10088.99.0.0/1688.99.0.1 to 88.99.255.25488.99.255.25565,534
10188.100.0.0/1688.100.0.1 to 88.100.255.25488.100.255.25565,534
10288.101.0.0/1688.101.0.1 to 88.101.255.25488.101.255.25565,534
10388.102.0.0/1688.102.0.1 to 88.102.255.25488.102.255.25565,534
10488.103.0.0/1688.103.0.1 to 88.103.255.25488.103.255.25565,534
10588.104.0.0/1688.104.0.1 to 88.104.255.25488.104.255.25565,534
10688.105.0.0/1688.105.0.1 to 88.105.255.25488.105.255.25565,534
10788.106.0.0/1688.106.0.1 to 88.106.255.25488.106.255.25565,534
10888.107.0.0/1688.107.0.1 to 88.107.255.25488.107.255.25565,534
10988.108.0.0/1688.108.0.1 to 88.108.255.25488.108.255.25565,534
11088.109.0.0/1688.109.0.1 to 88.109.255.25488.109.255.25565,534
11188.110.0.0/1688.110.0.1 to 88.110.255.25488.110.255.25565,534
11288.111.0.0/1688.111.0.1 to 88.111.255.25488.111.255.25565,534
11388.112.0.0/1688.112.0.1 to 88.112.255.25488.112.255.25565,534
11488.113.0.0/1688.113.0.1 to 88.113.255.25488.113.255.25565,534
11588.114.0.0/1688.114.0.1 to 88.114.255.25488.114.255.25565,534
11688.115.0.0/1688.115.0.1 to 88.115.255.25488.115.255.25565,534
11788.116.0.0/1688.116.0.1 to 88.116.255.25488.116.255.25565,534
11888.117.0.0/1688.117.0.1 to 88.117.255.25488.117.255.25565,534
11988.118.0.0/1688.118.0.1 to 88.118.255.25488.118.255.25565,534
12088.119.0.0/1688.119.0.1 to 88.119.255.25488.119.255.25565,534
12188.120.0.0/1688.120.0.1 to 88.120.255.25488.120.255.25565,534
12288.121.0.0/1688.121.0.1 to 88.121.255.25488.121.255.25565,534
12388.122.0.0/1688.122.0.1 to 88.122.255.25488.122.255.25565,534
12488.123.0.0/1688.123.0.1 to 88.123.255.25488.123.255.25565,534
12588.124.0.0/1688.124.0.1 to 88.124.255.25488.124.255.25565,534
12688.125.0.0/1688.125.0.1 to 88.125.255.25488.125.255.25565,534
12788.126.0.0/1688.126.0.1 to 88.126.255.25488.126.255.25565,534
12888.127.0.0/1688.127.0.1 to 88.127.255.25488.127.255.25565,534
12988.128.0.0/1688.128.0.1 to 88.128.255.25488.128.255.25565,534
13088.129.0.0/1688.129.0.1 to 88.129.255.25488.129.255.25565,534
13188.130.0.0/1688.130.0.1 to 88.130.255.25488.130.255.25565,534
13288.131.0.0/1688.131.0.1 to 88.131.255.25488.131.255.25565,534
13388.132.0.0/1688.132.0.1 to 88.132.255.25488.132.255.25565,534
13488.133.0.0/1688.133.0.1 to 88.133.255.25488.133.255.25565,534
13588.134.0.0/1688.134.0.1 to 88.134.255.25488.134.255.25565,534
13688.135.0.0/1688.135.0.1 to 88.135.255.25488.135.255.25565,534
13788.136.0.0/1688.136.0.1 to 88.136.255.25488.136.255.25565,534
13888.137.0.0/1688.137.0.1 to 88.137.255.25488.137.255.25565,534
13988.138.0.0/1688.138.0.1 to 88.138.255.25488.138.255.25565,534
14088.139.0.0/1688.139.0.1 to 88.139.255.25488.139.255.25565,534
14188.140.0.0/1688.140.0.1 to 88.140.255.25488.140.255.25565,534
14288.141.0.0/1688.141.0.1 to 88.141.255.25488.141.255.25565,534
14388.142.0.0/1688.142.0.1 to 88.142.255.25488.142.255.25565,534
14488.143.0.0/1688.143.0.1 to 88.143.255.25488.143.255.25565,534
14588.144.0.0/1688.144.0.1 to 88.144.255.25488.144.255.25565,534
14688.145.0.0/1688.145.0.1 to 88.145.255.25488.145.255.25565,534
14788.146.0.0/1688.146.0.1 to 88.146.255.25488.146.255.25565,534
14888.147.0.0/1688.147.0.1 to 88.147.255.25488.147.255.25565,534
14988.148.0.0/1688.148.0.1 to 88.148.255.25488.148.255.25565,534
15088.149.0.0/1688.149.0.1 to 88.149.255.25488.149.255.25565,534
15188.150.0.0/1688.150.0.1 to 88.150.255.25488.150.255.25565,534
15288.151.0.0/1688.151.0.1 to 88.151.255.25488.151.255.25565,534
15388.152.0.0/1688.152.0.1 to 88.152.255.25488.152.255.25565,534
15488.153.0.0/1688.153.0.1 to 88.153.255.25488.153.255.25565,534
15588.154.0.0/1688.154.0.1 to 88.154.255.25488.154.255.25565,534
15688.155.0.0/1688.155.0.1 to 88.155.255.25488.155.255.25565,534
15788.156.0.0/1688.156.0.1 to 88.156.255.25488.156.255.25565,534
15888.157.0.0/1688.157.0.1 to 88.157.255.25488.157.255.25565,534
15988.158.0.0/1688.158.0.1 to 88.158.255.25488.158.255.25565,534
16088.159.0.0/1688.159.0.1 to 88.159.255.25488.159.255.25565,534
16188.160.0.0/1688.160.0.1 to 88.160.255.25488.160.255.25565,534
16288.161.0.0/1688.161.0.1 to 88.161.255.25488.161.255.25565,534
16388.162.0.0/1688.162.0.1 to 88.162.255.25488.162.255.25565,534
16488.163.0.0/1688.163.0.1 to 88.163.255.25488.163.255.25565,534
16588.164.0.0/1688.164.0.1 to 88.164.255.25488.164.255.25565,534
16688.165.0.0/1688.165.0.1 to 88.165.255.25488.165.255.25565,534
16788.166.0.0/1688.166.0.1 to 88.166.255.25488.166.255.25565,534
16888.167.0.0/1688.167.0.1 to 88.167.255.25488.167.255.25565,534
16988.168.0.0/1688.168.0.1 to 88.168.255.25488.168.255.25565,534
17088.169.0.0/1688.169.0.1 to 88.169.255.25488.169.255.25565,534
17188.170.0.0/1688.170.0.1 to 88.170.255.25488.170.255.25565,534
17288.171.0.0/1688.171.0.1 to 88.171.255.25488.171.255.25565,534
17388.172.0.0/1688.172.0.1 to 88.172.255.25488.172.255.25565,534
17488.173.0.0/1688.173.0.1 to 88.173.255.25488.173.255.25565,534
17588.174.0.0/1688.174.0.1 to 88.174.255.25488.174.255.25565,534
17688.175.0.0/1688.175.0.1 to 88.175.255.25488.175.255.25565,534
17788.176.0.0/1688.176.0.1 to 88.176.255.25488.176.255.25565,534
17888.177.0.0/1688.177.0.1 to 88.177.255.25488.177.255.25565,534
17988.178.0.0/1688.178.0.1 to 88.178.255.25488.178.255.25565,534
18088.179.0.0/1688.179.0.1 to 88.179.255.25488.179.255.25565,534
18188.180.0.0/1688.180.0.1 to 88.180.255.25488.180.255.25565,534
18288.181.0.0/1688.181.0.1 to 88.181.255.25488.181.255.25565,534
18388.182.0.0/1688.182.0.1 to 88.182.255.25488.182.255.25565,534
18488.183.0.0/1688.183.0.1 to 88.183.255.25488.183.255.25565,534
18588.184.0.0/1688.184.0.1 to 88.184.255.25488.184.255.25565,534
18688.185.0.0/1688.185.0.1 to 88.185.255.25488.185.255.25565,534
18788.186.0.0/1688.186.0.1 to 88.186.255.25488.186.255.25565,534
18888.187.0.0/1688.187.0.1 to 88.187.255.25488.187.255.25565,534
18988.188.0.0/1688.188.0.1 to 88.188.255.25488.188.255.25565,534
19088.189.0.0/1688.189.0.1 to 88.189.255.25488.189.255.25565,534
19188.190.0.0/1688.190.0.1 to 88.190.255.25488.190.255.25565,534
19288.191.0.0/1688.191.0.1 to 88.191.255.25488.191.255.25565,534
19388.192.0.0/1688.192.0.1 to 88.192.255.25488.192.255.25565,534
19488.193.0.0/1688.193.0.1 to 88.193.255.25488.193.255.25565,534
19588.194.0.0/1688.194.0.1 to 88.194.255.25488.194.255.25565,534
19688.195.0.0/1688.195.0.1 to 88.195.255.25488.195.255.25565,534
19788.196.0.0/1688.196.0.1 to 88.196.255.25488.196.255.25565,534
19888.197.0.0/1688.197.0.1 to 88.197.255.25488.197.255.25565,534
19988.198.0.0/1688.198.0.1 to 88.198.255.25488.198.255.25565,534
20088.199.0.0/1688.199.0.1 to 88.199.255.25488.199.255.25565,534
20188.200.0.0/1688.200.0.1 to 88.200.255.25488.200.255.25565,534
20288.201.0.0/1688.201.0.1 to 88.201.255.25488.201.255.25565,534
20388.202.0.0/1688.202.0.1 to 88.202.255.25488.202.255.25565,534
20488.203.0.0/1688.203.0.1 to 88.203.255.25488.203.255.25565,534
20588.204.0.0/1688.204.0.1 to 88.204.255.25488.204.255.25565,534
20688.205.0.0/1688.205.0.1 to 88.205.255.25488.205.255.25565,534
20788.206.0.0/1688.206.0.1 to 88.206.255.25488.206.255.25565,534
20888.207.0.0/1688.207.0.1 to 88.207.255.25488.207.255.25565,534
20988.208.0.0/1688.208.0.1 to 88.208.255.25488.208.255.25565,534
21088.209.0.0/1688.209.0.1 to 88.209.255.25488.209.255.25565,534
21188.210.0.0/1688.210.0.1 to 88.210.255.25488.210.255.25565,534
21288.211.0.0/1688.211.0.1 to 88.211.255.25488.211.255.25565,534
21388.212.0.0/1688.212.0.1 to 88.212.255.25488.212.255.25565,534
21488.213.0.0/1688.213.0.1 to 88.213.255.25488.213.255.25565,534
21588.214.0.0/1688.214.0.1 to 88.214.255.25488.214.255.25565,534
21688.215.0.0/1688.215.0.1 to 88.215.255.25488.215.255.25565,534
21788.216.0.0/1688.216.0.1 to 88.216.255.25488.216.255.25565,534
21888.217.0.0/1688.217.0.1 to 88.217.255.25488.217.255.25565,534
21988.218.0.0/1688.218.0.1 to 88.218.255.25488.218.255.25565,534
22088.219.0.0/1688.219.0.1 to 88.219.255.25488.219.255.25565,534
22188.220.0.0/1688.220.0.1 to 88.220.255.25488.220.255.25565,534
22288.221.0.0/1688.221.0.1 to 88.221.255.25488.221.255.25565,534
22388.222.0.0/1688.222.0.1 to 88.222.255.25488.222.255.25565,534
22488.223.0.0/1688.223.0.1 to 88.223.255.25488.223.255.25565,534
22588.224.0.0/1688.224.0.1 to 88.224.255.25488.224.255.25565,534
22688.225.0.0/1688.225.0.1 to 88.225.255.25488.225.255.25565,534
22788.226.0.0/1688.226.0.1 to 88.226.255.25488.226.255.25565,534
22888.227.0.0/1688.227.0.1 to 88.227.255.25488.227.255.25565,534
22988.228.0.0/1688.228.0.1 to 88.228.255.25488.228.255.25565,534
23088.229.0.0/1688.229.0.1 to 88.229.255.25488.229.255.25565,534
23188.230.0.0/1688.230.0.1 to 88.230.255.25488.230.255.25565,534
23288.231.0.0/1688.231.0.1 to 88.231.255.25488.231.255.25565,534
23388.232.0.0/1688.232.0.1 to 88.232.255.25488.232.255.25565,534
23488.233.0.0/1688.233.0.1 to 88.233.255.25488.233.255.25565,534
23588.234.0.0/1688.234.0.1 to 88.234.255.25488.234.255.25565,534
23688.235.0.0/1688.235.0.1 to 88.235.255.25488.235.255.25565,534
23788.236.0.0/1688.236.0.1 to 88.236.255.25488.236.255.25565,534
23888.237.0.0/1688.237.0.1 to 88.237.255.25488.237.255.25565,534
23988.238.0.0/1688.238.0.1 to 88.238.255.25488.238.255.25565,534
24088.239.0.0/1688.239.0.1 to 88.239.255.25488.239.255.25565,534
24188.240.0.0/1688.240.0.1 to 88.240.255.25488.240.255.25565,534
24288.241.0.0/1688.241.0.1 to 88.241.255.25488.241.255.25565,534
24388.242.0.0/1688.242.0.1 to 88.242.255.25488.242.255.25565,534
24488.243.0.0/1688.243.0.1 to 88.243.255.25488.243.255.25565,534
24588.244.0.0/1688.244.0.1 to 88.244.255.25488.244.255.25565,534
24688.245.0.0/1688.245.0.1 to 88.245.255.25488.245.255.25565,534
24788.246.0.0/1688.246.0.1 to 88.246.255.25488.246.255.25565,534
24888.247.0.0/1688.247.0.1 to 88.247.255.25488.247.255.25565,534
24988.248.0.0/1688.248.0.1 to 88.248.255.25488.248.255.25565,534
25088.249.0.0/1688.249.0.1 to 88.249.255.25488.249.255.25565,534
25188.250.0.0/1688.250.0.1 to 88.250.255.25488.250.255.25565,534
25288.251.0.0/1688.251.0.1 to 88.251.255.25488.251.255.25565,534
25388.252.0.0/1688.252.0.1 to 88.252.255.25488.252.255.25565,534
25488.253.0.0/1688.253.0.1 to 88.253.255.25488.253.255.25565,534
25588.254.0.0/1688.254.0.1 to 88.254.255.25488.254.255.25565,534
25688.255.0.0/1688.255.0.1 to 88.255.255.25488.255.255.25565,534

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.