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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.

Network11.84.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
11.84.0.0
Broadcast address
11.87.255.255
First usable
11.84.0.1
Last usable
11.87.255.254
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 0B540000 · Integer 190054400 to 190316543
Reverse DNS zones
84.11.in-addr.arpa
85.11.in-addr.arpa
86.11.in-addr.arpa
87.11.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
Address00001011.01010100.00000000.0000000011.84.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00001011.01010100.00000000.0000000011.84.0.0
Broadcast00001011.01010111.11111111.1111111111.87.255.255
Split into smaller subnets/24
/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)

11.84.0.0/14 makes 1,024 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
111.84.0.0/2411.84.0.1 to 11.84.0.25411.84.0.255254
211.84.1.0/2411.84.1.1 to 11.84.1.25411.84.1.255254
311.84.2.0/2411.84.2.1 to 11.84.2.25411.84.2.255254
411.84.3.0/2411.84.3.1 to 11.84.3.25411.84.3.255254
511.84.4.0/2411.84.4.1 to 11.84.4.25411.84.4.255254
611.84.5.0/2411.84.5.1 to 11.84.5.25411.84.5.255254
711.84.6.0/2411.84.6.1 to 11.84.6.25411.84.6.255254
811.84.7.0/2411.84.7.1 to 11.84.7.25411.84.7.255254
911.84.8.0/2411.84.8.1 to 11.84.8.25411.84.8.255254
1011.84.9.0/2411.84.9.1 to 11.84.9.25411.84.9.255254
1111.84.10.0/2411.84.10.1 to 11.84.10.25411.84.10.255254
1211.84.11.0/2411.84.11.1 to 11.84.11.25411.84.11.255254
1311.84.12.0/2411.84.12.1 to 11.84.12.25411.84.12.255254
1411.84.13.0/2411.84.13.1 to 11.84.13.25411.84.13.255254
1511.84.14.0/2411.84.14.1 to 11.84.14.25411.84.14.255254
1611.84.15.0/2411.84.15.1 to 11.84.15.25411.84.15.255254
1711.84.16.0/2411.84.16.1 to 11.84.16.25411.84.16.255254
1811.84.17.0/2411.84.17.1 to 11.84.17.25411.84.17.255254
1911.84.18.0/2411.84.18.1 to 11.84.18.25411.84.18.255254
2011.84.19.0/2411.84.19.1 to 11.84.19.25411.84.19.255254
2111.84.20.0/2411.84.20.1 to 11.84.20.25411.84.20.255254
2211.84.21.0/2411.84.21.1 to 11.84.21.25411.84.21.255254
2311.84.22.0/2411.84.22.1 to 11.84.22.25411.84.22.255254
2411.84.23.0/2411.84.23.1 to 11.84.23.25411.84.23.255254
2511.84.24.0/2411.84.24.1 to 11.84.24.25411.84.24.255254
2611.84.25.0/2411.84.25.1 to 11.84.25.25411.84.25.255254
2711.84.26.0/2411.84.26.1 to 11.84.26.25411.84.26.255254
2811.84.27.0/2411.84.27.1 to 11.84.27.25411.84.27.255254
2911.84.28.0/2411.84.28.1 to 11.84.28.25411.84.28.255254
3011.84.29.0/2411.84.29.1 to 11.84.29.25411.84.29.255254
3111.84.30.0/2411.84.30.1 to 11.84.30.25411.84.30.255254
3211.84.31.0/2411.84.31.1 to 11.84.31.25411.84.31.255254
3311.84.32.0/2411.84.32.1 to 11.84.32.25411.84.32.255254
3411.84.33.0/2411.84.33.1 to 11.84.33.25411.84.33.255254
3511.84.34.0/2411.84.34.1 to 11.84.34.25411.84.34.255254
3611.84.35.0/2411.84.35.1 to 11.84.35.25411.84.35.255254
3711.84.36.0/2411.84.36.1 to 11.84.36.25411.84.36.255254
3811.84.37.0/2411.84.37.1 to 11.84.37.25411.84.37.255254
3911.84.38.0/2411.84.38.1 to 11.84.38.25411.84.38.255254
4011.84.39.0/2411.84.39.1 to 11.84.39.25411.84.39.255254
4111.84.40.0/2411.84.40.1 to 11.84.40.25411.84.40.255254
4211.84.41.0/2411.84.41.1 to 11.84.41.25411.84.41.255254
4311.84.42.0/2411.84.42.1 to 11.84.42.25411.84.42.255254
4411.84.43.0/2411.84.43.1 to 11.84.43.25411.84.43.255254
4511.84.44.0/2411.84.44.1 to 11.84.44.25411.84.44.255254
4611.84.45.0/2411.84.45.1 to 11.84.45.25411.84.45.255254
4711.84.46.0/2411.84.46.1 to 11.84.46.25411.84.46.255254
4811.84.47.0/2411.84.47.1 to 11.84.47.25411.84.47.255254
4911.84.48.0/2411.84.48.1 to 11.84.48.25411.84.48.255254
5011.84.49.0/2411.84.49.1 to 11.84.49.25411.84.49.255254
5111.84.50.0/2411.84.50.1 to 11.84.50.25411.84.50.255254
5211.84.51.0/2411.84.51.1 to 11.84.51.25411.84.51.255254
5311.84.52.0/2411.84.52.1 to 11.84.52.25411.84.52.255254
5411.84.53.0/2411.84.53.1 to 11.84.53.25411.84.53.255254
5511.84.54.0/2411.84.54.1 to 11.84.54.25411.84.54.255254
5611.84.55.0/2411.84.55.1 to 11.84.55.25411.84.55.255254
5711.84.56.0/2411.84.56.1 to 11.84.56.25411.84.56.255254
5811.84.57.0/2411.84.57.1 to 11.84.57.25411.84.57.255254
5911.84.58.0/2411.84.58.1 to 11.84.58.25411.84.58.255254
6011.84.59.0/2411.84.59.1 to 11.84.59.25411.84.59.255254
6111.84.60.0/2411.84.60.1 to 11.84.60.25411.84.60.255254
6211.84.61.0/2411.84.61.1 to 11.84.61.25411.84.61.255254
6311.84.62.0/2411.84.62.1 to 11.84.62.25411.84.62.255254
6411.84.63.0/2411.84.63.1 to 11.84.63.25411.84.63.255254
6511.84.64.0/2411.84.64.1 to 11.84.64.25411.84.64.255254
6611.84.65.0/2411.84.65.1 to 11.84.65.25411.84.65.255254
6711.84.66.0/2411.84.66.1 to 11.84.66.25411.84.66.255254
6811.84.67.0/2411.84.67.1 to 11.84.67.25411.84.67.255254
6911.84.68.0/2411.84.68.1 to 11.84.68.25411.84.68.255254
7011.84.69.0/2411.84.69.1 to 11.84.69.25411.84.69.255254
7111.84.70.0/2411.84.70.1 to 11.84.70.25411.84.70.255254
7211.84.71.0/2411.84.71.1 to 11.84.71.25411.84.71.255254
7311.84.72.0/2411.84.72.1 to 11.84.72.25411.84.72.255254
7411.84.73.0/2411.84.73.1 to 11.84.73.25411.84.73.255254
7511.84.74.0/2411.84.74.1 to 11.84.74.25411.84.74.255254
7611.84.75.0/2411.84.75.1 to 11.84.75.25411.84.75.255254
7711.84.76.0/2411.84.76.1 to 11.84.76.25411.84.76.255254
7811.84.77.0/2411.84.77.1 to 11.84.77.25411.84.77.255254
7911.84.78.0/2411.84.78.1 to 11.84.78.25411.84.78.255254
8011.84.79.0/2411.84.79.1 to 11.84.79.25411.84.79.255254
8111.84.80.0/2411.84.80.1 to 11.84.80.25411.84.80.255254
8211.84.81.0/2411.84.81.1 to 11.84.81.25411.84.81.255254
8311.84.82.0/2411.84.82.1 to 11.84.82.25411.84.82.255254
8411.84.83.0/2411.84.83.1 to 11.84.83.25411.84.83.255254
8511.84.84.0/2411.84.84.1 to 11.84.84.25411.84.84.255254
8611.84.85.0/2411.84.85.1 to 11.84.85.25411.84.85.255254
8711.84.86.0/2411.84.86.1 to 11.84.86.25411.84.86.255254
8811.84.87.0/2411.84.87.1 to 11.84.87.25411.84.87.255254
8911.84.88.0/2411.84.88.1 to 11.84.88.25411.84.88.255254
9011.84.89.0/2411.84.89.1 to 11.84.89.25411.84.89.255254
9111.84.90.0/2411.84.90.1 to 11.84.90.25411.84.90.255254
9211.84.91.0/2411.84.91.1 to 11.84.91.25411.84.91.255254
9311.84.92.0/2411.84.92.1 to 11.84.92.25411.84.92.255254
9411.84.93.0/2411.84.93.1 to 11.84.93.25411.84.93.255254
9511.84.94.0/2411.84.94.1 to 11.84.94.25411.84.94.255254
9611.84.95.0/2411.84.95.1 to 11.84.95.25411.84.95.255254
9711.84.96.0/2411.84.96.1 to 11.84.96.25411.84.96.255254
9811.84.97.0/2411.84.97.1 to 11.84.97.25411.84.97.255254
9911.84.98.0/2411.84.98.1 to 11.84.98.25411.84.98.255254
10011.84.99.0/2411.84.99.1 to 11.84.99.25411.84.99.255254
10111.84.100.0/2411.84.100.1 to 11.84.100.25411.84.100.255254
10211.84.101.0/2411.84.101.1 to 11.84.101.25411.84.101.255254
10311.84.102.0/2411.84.102.1 to 11.84.102.25411.84.102.255254
10411.84.103.0/2411.84.103.1 to 11.84.103.25411.84.103.255254
10511.84.104.0/2411.84.104.1 to 11.84.104.25411.84.104.255254
10611.84.105.0/2411.84.105.1 to 11.84.105.25411.84.105.255254
10711.84.106.0/2411.84.106.1 to 11.84.106.25411.84.106.255254
10811.84.107.0/2411.84.107.1 to 11.84.107.25411.84.107.255254
10911.84.108.0/2411.84.108.1 to 11.84.108.25411.84.108.255254
11011.84.109.0/2411.84.109.1 to 11.84.109.25411.84.109.255254
11111.84.110.0/2411.84.110.1 to 11.84.110.25411.84.110.255254
11211.84.111.0/2411.84.111.1 to 11.84.111.25411.84.111.255254
11311.84.112.0/2411.84.112.1 to 11.84.112.25411.84.112.255254
11411.84.113.0/2411.84.113.1 to 11.84.113.25411.84.113.255254
11511.84.114.0/2411.84.114.1 to 11.84.114.25411.84.114.255254
11611.84.115.0/2411.84.115.1 to 11.84.115.25411.84.115.255254
11711.84.116.0/2411.84.116.1 to 11.84.116.25411.84.116.255254
11811.84.117.0/2411.84.117.1 to 11.84.117.25411.84.117.255254
11911.84.118.0/2411.84.118.1 to 11.84.118.25411.84.118.255254
12011.84.119.0/2411.84.119.1 to 11.84.119.25411.84.119.255254
12111.84.120.0/2411.84.120.1 to 11.84.120.25411.84.120.255254
12211.84.121.0/2411.84.121.1 to 11.84.121.25411.84.121.255254
12311.84.122.0/2411.84.122.1 to 11.84.122.25411.84.122.255254
12411.84.123.0/2411.84.123.1 to 11.84.123.25411.84.123.255254
12511.84.124.0/2411.84.124.1 to 11.84.124.25411.84.124.255254
12611.84.125.0/2411.84.125.1 to 11.84.125.25411.84.125.255254
12711.84.126.0/2411.84.126.1 to 11.84.126.25411.84.126.255254
12811.84.127.0/2411.84.127.1 to 11.84.127.25411.84.127.255254
12911.84.128.0/2411.84.128.1 to 11.84.128.25411.84.128.255254
13011.84.129.0/2411.84.129.1 to 11.84.129.25411.84.129.255254
13111.84.130.0/2411.84.130.1 to 11.84.130.25411.84.130.255254
13211.84.131.0/2411.84.131.1 to 11.84.131.25411.84.131.255254
13311.84.132.0/2411.84.132.1 to 11.84.132.25411.84.132.255254
13411.84.133.0/2411.84.133.1 to 11.84.133.25411.84.133.255254
13511.84.134.0/2411.84.134.1 to 11.84.134.25411.84.134.255254
13611.84.135.0/2411.84.135.1 to 11.84.135.25411.84.135.255254
13711.84.136.0/2411.84.136.1 to 11.84.136.25411.84.136.255254
13811.84.137.0/2411.84.137.1 to 11.84.137.25411.84.137.255254
13911.84.138.0/2411.84.138.1 to 11.84.138.25411.84.138.255254
14011.84.139.0/2411.84.139.1 to 11.84.139.25411.84.139.255254
14111.84.140.0/2411.84.140.1 to 11.84.140.25411.84.140.255254
14211.84.141.0/2411.84.141.1 to 11.84.141.25411.84.141.255254
14311.84.142.0/2411.84.142.1 to 11.84.142.25411.84.142.255254
14411.84.143.0/2411.84.143.1 to 11.84.143.25411.84.143.255254
14511.84.144.0/2411.84.144.1 to 11.84.144.25411.84.144.255254
14611.84.145.0/2411.84.145.1 to 11.84.145.25411.84.145.255254
14711.84.146.0/2411.84.146.1 to 11.84.146.25411.84.146.255254
14811.84.147.0/2411.84.147.1 to 11.84.147.25411.84.147.255254
14911.84.148.0/2411.84.148.1 to 11.84.148.25411.84.148.255254
15011.84.149.0/2411.84.149.1 to 11.84.149.25411.84.149.255254
15111.84.150.0/2411.84.150.1 to 11.84.150.25411.84.150.255254
15211.84.151.0/2411.84.151.1 to 11.84.151.25411.84.151.255254
15311.84.152.0/2411.84.152.1 to 11.84.152.25411.84.152.255254
15411.84.153.0/2411.84.153.1 to 11.84.153.25411.84.153.255254
15511.84.154.0/2411.84.154.1 to 11.84.154.25411.84.154.255254
15611.84.155.0/2411.84.155.1 to 11.84.155.25411.84.155.255254
15711.84.156.0/2411.84.156.1 to 11.84.156.25411.84.156.255254
15811.84.157.0/2411.84.157.1 to 11.84.157.25411.84.157.255254
15911.84.158.0/2411.84.158.1 to 11.84.158.25411.84.158.255254
16011.84.159.0/2411.84.159.1 to 11.84.159.25411.84.159.255254
16111.84.160.0/2411.84.160.1 to 11.84.160.25411.84.160.255254
16211.84.161.0/2411.84.161.1 to 11.84.161.25411.84.161.255254
16311.84.162.0/2411.84.162.1 to 11.84.162.25411.84.162.255254
16411.84.163.0/2411.84.163.1 to 11.84.163.25411.84.163.255254
16511.84.164.0/2411.84.164.1 to 11.84.164.25411.84.164.255254
16611.84.165.0/2411.84.165.1 to 11.84.165.25411.84.165.255254
16711.84.166.0/2411.84.166.1 to 11.84.166.25411.84.166.255254
16811.84.167.0/2411.84.167.1 to 11.84.167.25411.84.167.255254
16911.84.168.0/2411.84.168.1 to 11.84.168.25411.84.168.255254
17011.84.169.0/2411.84.169.1 to 11.84.169.25411.84.169.255254
17111.84.170.0/2411.84.170.1 to 11.84.170.25411.84.170.255254
17211.84.171.0/2411.84.171.1 to 11.84.171.25411.84.171.255254
17311.84.172.0/2411.84.172.1 to 11.84.172.25411.84.172.255254
17411.84.173.0/2411.84.173.1 to 11.84.173.25411.84.173.255254
17511.84.174.0/2411.84.174.1 to 11.84.174.25411.84.174.255254
17611.84.175.0/2411.84.175.1 to 11.84.175.25411.84.175.255254
17711.84.176.0/2411.84.176.1 to 11.84.176.25411.84.176.255254
17811.84.177.0/2411.84.177.1 to 11.84.177.25411.84.177.255254
17911.84.178.0/2411.84.178.1 to 11.84.178.25411.84.178.255254
18011.84.179.0/2411.84.179.1 to 11.84.179.25411.84.179.255254
18111.84.180.0/2411.84.180.1 to 11.84.180.25411.84.180.255254
18211.84.181.0/2411.84.181.1 to 11.84.181.25411.84.181.255254
18311.84.182.0/2411.84.182.1 to 11.84.182.25411.84.182.255254
18411.84.183.0/2411.84.183.1 to 11.84.183.25411.84.183.255254
18511.84.184.0/2411.84.184.1 to 11.84.184.25411.84.184.255254
18611.84.185.0/2411.84.185.1 to 11.84.185.25411.84.185.255254
18711.84.186.0/2411.84.186.1 to 11.84.186.25411.84.186.255254
18811.84.187.0/2411.84.187.1 to 11.84.187.25411.84.187.255254
18911.84.188.0/2411.84.188.1 to 11.84.188.25411.84.188.255254
19011.84.189.0/2411.84.189.1 to 11.84.189.25411.84.189.255254
19111.84.190.0/2411.84.190.1 to 11.84.190.25411.84.190.255254
19211.84.191.0/2411.84.191.1 to 11.84.191.25411.84.191.255254
19311.84.192.0/2411.84.192.1 to 11.84.192.25411.84.192.255254
19411.84.193.0/2411.84.193.1 to 11.84.193.25411.84.193.255254
19511.84.194.0/2411.84.194.1 to 11.84.194.25411.84.194.255254
19611.84.195.0/2411.84.195.1 to 11.84.195.25411.84.195.255254
19711.84.196.0/2411.84.196.1 to 11.84.196.25411.84.196.255254
19811.84.197.0/2411.84.197.1 to 11.84.197.25411.84.197.255254
19911.84.198.0/2411.84.198.1 to 11.84.198.25411.84.198.255254
20011.84.199.0/2411.84.199.1 to 11.84.199.25411.84.199.255254
20111.84.200.0/2411.84.200.1 to 11.84.200.25411.84.200.255254
20211.84.201.0/2411.84.201.1 to 11.84.201.25411.84.201.255254
20311.84.202.0/2411.84.202.1 to 11.84.202.25411.84.202.255254
20411.84.203.0/2411.84.203.1 to 11.84.203.25411.84.203.255254
20511.84.204.0/2411.84.204.1 to 11.84.204.25411.84.204.255254
20611.84.205.0/2411.84.205.1 to 11.84.205.25411.84.205.255254
20711.84.206.0/2411.84.206.1 to 11.84.206.25411.84.206.255254
20811.84.207.0/2411.84.207.1 to 11.84.207.25411.84.207.255254
20911.84.208.0/2411.84.208.1 to 11.84.208.25411.84.208.255254
21011.84.209.0/2411.84.209.1 to 11.84.209.25411.84.209.255254
21111.84.210.0/2411.84.210.1 to 11.84.210.25411.84.210.255254
21211.84.211.0/2411.84.211.1 to 11.84.211.25411.84.211.255254
21311.84.212.0/2411.84.212.1 to 11.84.212.25411.84.212.255254
21411.84.213.0/2411.84.213.1 to 11.84.213.25411.84.213.255254
21511.84.214.0/2411.84.214.1 to 11.84.214.25411.84.214.255254
21611.84.215.0/2411.84.215.1 to 11.84.215.25411.84.215.255254
21711.84.216.0/2411.84.216.1 to 11.84.216.25411.84.216.255254
21811.84.217.0/2411.84.217.1 to 11.84.217.25411.84.217.255254
21911.84.218.0/2411.84.218.1 to 11.84.218.25411.84.218.255254
22011.84.219.0/2411.84.219.1 to 11.84.219.25411.84.219.255254
22111.84.220.0/2411.84.220.1 to 11.84.220.25411.84.220.255254
22211.84.221.0/2411.84.221.1 to 11.84.221.25411.84.221.255254
22311.84.222.0/2411.84.222.1 to 11.84.222.25411.84.222.255254
22411.84.223.0/2411.84.223.1 to 11.84.223.25411.84.223.255254
22511.84.224.0/2411.84.224.1 to 11.84.224.25411.84.224.255254
22611.84.225.0/2411.84.225.1 to 11.84.225.25411.84.225.255254
22711.84.226.0/2411.84.226.1 to 11.84.226.25411.84.226.255254
22811.84.227.0/2411.84.227.1 to 11.84.227.25411.84.227.255254
22911.84.228.0/2411.84.228.1 to 11.84.228.25411.84.228.255254
23011.84.229.0/2411.84.229.1 to 11.84.229.25411.84.229.255254
23111.84.230.0/2411.84.230.1 to 11.84.230.25411.84.230.255254
23211.84.231.0/2411.84.231.1 to 11.84.231.25411.84.231.255254
23311.84.232.0/2411.84.232.1 to 11.84.232.25411.84.232.255254
23411.84.233.0/2411.84.233.1 to 11.84.233.25411.84.233.255254
23511.84.234.0/2411.84.234.1 to 11.84.234.25411.84.234.255254
23611.84.235.0/2411.84.235.1 to 11.84.235.25411.84.235.255254
23711.84.236.0/2411.84.236.1 to 11.84.236.25411.84.236.255254
23811.84.237.0/2411.84.237.1 to 11.84.237.25411.84.237.255254
23911.84.238.0/2411.84.238.1 to 11.84.238.25411.84.238.255254
24011.84.239.0/2411.84.239.1 to 11.84.239.25411.84.239.255254
24111.84.240.0/2411.84.240.1 to 11.84.240.25411.84.240.255254
24211.84.241.0/2411.84.241.1 to 11.84.241.25411.84.241.255254
24311.84.242.0/2411.84.242.1 to 11.84.242.25411.84.242.255254
24411.84.243.0/2411.84.243.1 to 11.84.243.25411.84.243.255254
24511.84.244.0/2411.84.244.1 to 11.84.244.25411.84.244.255254
24611.84.245.0/2411.84.245.1 to 11.84.245.25411.84.245.255254
24711.84.246.0/2411.84.246.1 to 11.84.246.25411.84.246.255254
24811.84.247.0/2411.84.247.1 to 11.84.247.25411.84.247.255254
24911.84.248.0/2411.84.248.1 to 11.84.248.25411.84.248.255254
25011.84.249.0/2411.84.249.1 to 11.84.249.25411.84.249.255254
25111.84.250.0/2411.84.250.1 to 11.84.250.25411.84.250.255254
25211.84.251.0/2411.84.251.1 to 11.84.251.25411.84.251.255254
25311.84.252.0/2411.84.252.1 to 11.84.252.25411.84.252.255254
25411.84.253.0/2411.84.253.1 to 11.84.253.25411.84.253.255254
25511.84.254.0/2411.84.254.1 to 11.84.254.25411.84.254.255254
25611.84.255.0/2411.84.255.1 to 11.84.255.25411.84.255.255254

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.