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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.

Network27.0.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
27.0.0.0
Broadcast address
27.3.255.255
First usable
27.0.0.1
Last usable
27.3.255.254
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 1B000000 · Integer 452984832 to 453246975
Reverse DNS zones
0.27.in-addr.arpa
1.27.in-addr.arpa
2.27.in-addr.arpa
3.27.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
Address00011011.00000000.00000000.0000000027.0.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00011011.00000000.00000000.0000000027.0.0.0
Broadcast00011011.00000011.11111111.1111111127.3.255.255
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)

27.0.0.0/14 makes 1,024 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
127.0.0.0/2427.0.0.1 to 27.0.0.25427.0.0.255254
227.0.1.0/2427.0.1.1 to 27.0.1.25427.0.1.255254
327.0.2.0/2427.0.2.1 to 27.0.2.25427.0.2.255254
427.0.3.0/2427.0.3.1 to 27.0.3.25427.0.3.255254
527.0.4.0/2427.0.4.1 to 27.0.4.25427.0.4.255254
627.0.5.0/2427.0.5.1 to 27.0.5.25427.0.5.255254
727.0.6.0/2427.0.6.1 to 27.0.6.25427.0.6.255254
827.0.7.0/2427.0.7.1 to 27.0.7.25427.0.7.255254
927.0.8.0/2427.0.8.1 to 27.0.8.25427.0.8.255254
1027.0.9.0/2427.0.9.1 to 27.0.9.25427.0.9.255254
1127.0.10.0/2427.0.10.1 to 27.0.10.25427.0.10.255254
1227.0.11.0/2427.0.11.1 to 27.0.11.25427.0.11.255254
1327.0.12.0/2427.0.12.1 to 27.0.12.25427.0.12.255254
1427.0.13.0/2427.0.13.1 to 27.0.13.25427.0.13.255254
1527.0.14.0/2427.0.14.1 to 27.0.14.25427.0.14.255254
1627.0.15.0/2427.0.15.1 to 27.0.15.25427.0.15.255254
1727.0.16.0/2427.0.16.1 to 27.0.16.25427.0.16.255254
1827.0.17.0/2427.0.17.1 to 27.0.17.25427.0.17.255254
1927.0.18.0/2427.0.18.1 to 27.0.18.25427.0.18.255254
2027.0.19.0/2427.0.19.1 to 27.0.19.25427.0.19.255254
2127.0.20.0/2427.0.20.1 to 27.0.20.25427.0.20.255254
2227.0.21.0/2427.0.21.1 to 27.0.21.25427.0.21.255254
2327.0.22.0/2427.0.22.1 to 27.0.22.25427.0.22.255254
2427.0.23.0/2427.0.23.1 to 27.0.23.25427.0.23.255254
2527.0.24.0/2427.0.24.1 to 27.0.24.25427.0.24.255254
2627.0.25.0/2427.0.25.1 to 27.0.25.25427.0.25.255254
2727.0.26.0/2427.0.26.1 to 27.0.26.25427.0.26.255254
2827.0.27.0/2427.0.27.1 to 27.0.27.25427.0.27.255254
2927.0.28.0/2427.0.28.1 to 27.0.28.25427.0.28.255254
3027.0.29.0/2427.0.29.1 to 27.0.29.25427.0.29.255254
3127.0.30.0/2427.0.30.1 to 27.0.30.25427.0.30.255254
3227.0.31.0/2427.0.31.1 to 27.0.31.25427.0.31.255254
3327.0.32.0/2427.0.32.1 to 27.0.32.25427.0.32.255254
3427.0.33.0/2427.0.33.1 to 27.0.33.25427.0.33.255254
3527.0.34.0/2427.0.34.1 to 27.0.34.25427.0.34.255254
3627.0.35.0/2427.0.35.1 to 27.0.35.25427.0.35.255254
3727.0.36.0/2427.0.36.1 to 27.0.36.25427.0.36.255254
3827.0.37.0/2427.0.37.1 to 27.0.37.25427.0.37.255254
3927.0.38.0/2427.0.38.1 to 27.0.38.25427.0.38.255254
4027.0.39.0/2427.0.39.1 to 27.0.39.25427.0.39.255254
4127.0.40.0/2427.0.40.1 to 27.0.40.25427.0.40.255254
4227.0.41.0/2427.0.41.1 to 27.0.41.25427.0.41.255254
4327.0.42.0/2427.0.42.1 to 27.0.42.25427.0.42.255254
4427.0.43.0/2427.0.43.1 to 27.0.43.25427.0.43.255254
4527.0.44.0/2427.0.44.1 to 27.0.44.25427.0.44.255254
4627.0.45.0/2427.0.45.1 to 27.0.45.25427.0.45.255254
4727.0.46.0/2427.0.46.1 to 27.0.46.25427.0.46.255254
4827.0.47.0/2427.0.47.1 to 27.0.47.25427.0.47.255254
4927.0.48.0/2427.0.48.1 to 27.0.48.25427.0.48.255254
5027.0.49.0/2427.0.49.1 to 27.0.49.25427.0.49.255254
5127.0.50.0/2427.0.50.1 to 27.0.50.25427.0.50.255254
5227.0.51.0/2427.0.51.1 to 27.0.51.25427.0.51.255254
5327.0.52.0/2427.0.52.1 to 27.0.52.25427.0.52.255254
5427.0.53.0/2427.0.53.1 to 27.0.53.25427.0.53.255254
5527.0.54.0/2427.0.54.1 to 27.0.54.25427.0.54.255254
5627.0.55.0/2427.0.55.1 to 27.0.55.25427.0.55.255254
5727.0.56.0/2427.0.56.1 to 27.0.56.25427.0.56.255254
5827.0.57.0/2427.0.57.1 to 27.0.57.25427.0.57.255254
5927.0.58.0/2427.0.58.1 to 27.0.58.25427.0.58.255254
6027.0.59.0/2427.0.59.1 to 27.0.59.25427.0.59.255254
6127.0.60.0/2427.0.60.1 to 27.0.60.25427.0.60.255254
6227.0.61.0/2427.0.61.1 to 27.0.61.25427.0.61.255254
6327.0.62.0/2427.0.62.1 to 27.0.62.25427.0.62.255254
6427.0.63.0/2427.0.63.1 to 27.0.63.25427.0.63.255254
6527.0.64.0/2427.0.64.1 to 27.0.64.25427.0.64.255254
6627.0.65.0/2427.0.65.1 to 27.0.65.25427.0.65.255254
6727.0.66.0/2427.0.66.1 to 27.0.66.25427.0.66.255254
6827.0.67.0/2427.0.67.1 to 27.0.67.25427.0.67.255254
6927.0.68.0/2427.0.68.1 to 27.0.68.25427.0.68.255254
7027.0.69.0/2427.0.69.1 to 27.0.69.25427.0.69.255254
7127.0.70.0/2427.0.70.1 to 27.0.70.25427.0.70.255254
7227.0.71.0/2427.0.71.1 to 27.0.71.25427.0.71.255254
7327.0.72.0/2427.0.72.1 to 27.0.72.25427.0.72.255254
7427.0.73.0/2427.0.73.1 to 27.0.73.25427.0.73.255254
7527.0.74.0/2427.0.74.1 to 27.0.74.25427.0.74.255254
7627.0.75.0/2427.0.75.1 to 27.0.75.25427.0.75.255254
7727.0.76.0/2427.0.76.1 to 27.0.76.25427.0.76.255254
7827.0.77.0/2427.0.77.1 to 27.0.77.25427.0.77.255254
7927.0.78.0/2427.0.78.1 to 27.0.78.25427.0.78.255254
8027.0.79.0/2427.0.79.1 to 27.0.79.25427.0.79.255254
8127.0.80.0/2427.0.80.1 to 27.0.80.25427.0.80.255254
8227.0.81.0/2427.0.81.1 to 27.0.81.25427.0.81.255254
8327.0.82.0/2427.0.82.1 to 27.0.82.25427.0.82.255254
8427.0.83.0/2427.0.83.1 to 27.0.83.25427.0.83.255254
8527.0.84.0/2427.0.84.1 to 27.0.84.25427.0.84.255254
8627.0.85.0/2427.0.85.1 to 27.0.85.25427.0.85.255254
8727.0.86.0/2427.0.86.1 to 27.0.86.25427.0.86.255254
8827.0.87.0/2427.0.87.1 to 27.0.87.25427.0.87.255254
8927.0.88.0/2427.0.88.1 to 27.0.88.25427.0.88.255254
9027.0.89.0/2427.0.89.1 to 27.0.89.25427.0.89.255254
9127.0.90.0/2427.0.90.1 to 27.0.90.25427.0.90.255254
9227.0.91.0/2427.0.91.1 to 27.0.91.25427.0.91.255254
9327.0.92.0/2427.0.92.1 to 27.0.92.25427.0.92.255254
9427.0.93.0/2427.0.93.1 to 27.0.93.25427.0.93.255254
9527.0.94.0/2427.0.94.1 to 27.0.94.25427.0.94.255254
9627.0.95.0/2427.0.95.1 to 27.0.95.25427.0.95.255254
9727.0.96.0/2427.0.96.1 to 27.0.96.25427.0.96.255254
9827.0.97.0/2427.0.97.1 to 27.0.97.25427.0.97.255254
9927.0.98.0/2427.0.98.1 to 27.0.98.25427.0.98.255254
10027.0.99.0/2427.0.99.1 to 27.0.99.25427.0.99.255254
10127.0.100.0/2427.0.100.1 to 27.0.100.25427.0.100.255254
10227.0.101.0/2427.0.101.1 to 27.0.101.25427.0.101.255254
10327.0.102.0/2427.0.102.1 to 27.0.102.25427.0.102.255254
10427.0.103.0/2427.0.103.1 to 27.0.103.25427.0.103.255254
10527.0.104.0/2427.0.104.1 to 27.0.104.25427.0.104.255254
10627.0.105.0/2427.0.105.1 to 27.0.105.25427.0.105.255254
10727.0.106.0/2427.0.106.1 to 27.0.106.25427.0.106.255254
10827.0.107.0/2427.0.107.1 to 27.0.107.25427.0.107.255254
10927.0.108.0/2427.0.108.1 to 27.0.108.25427.0.108.255254
11027.0.109.0/2427.0.109.1 to 27.0.109.25427.0.109.255254
11127.0.110.0/2427.0.110.1 to 27.0.110.25427.0.110.255254
11227.0.111.0/2427.0.111.1 to 27.0.111.25427.0.111.255254
11327.0.112.0/2427.0.112.1 to 27.0.112.25427.0.112.255254
11427.0.113.0/2427.0.113.1 to 27.0.113.25427.0.113.255254
11527.0.114.0/2427.0.114.1 to 27.0.114.25427.0.114.255254
11627.0.115.0/2427.0.115.1 to 27.0.115.25427.0.115.255254
11727.0.116.0/2427.0.116.1 to 27.0.116.25427.0.116.255254
11827.0.117.0/2427.0.117.1 to 27.0.117.25427.0.117.255254
11927.0.118.0/2427.0.118.1 to 27.0.118.25427.0.118.255254
12027.0.119.0/2427.0.119.1 to 27.0.119.25427.0.119.255254
12127.0.120.0/2427.0.120.1 to 27.0.120.25427.0.120.255254
12227.0.121.0/2427.0.121.1 to 27.0.121.25427.0.121.255254
12327.0.122.0/2427.0.122.1 to 27.0.122.25427.0.122.255254
12427.0.123.0/2427.0.123.1 to 27.0.123.25427.0.123.255254
12527.0.124.0/2427.0.124.1 to 27.0.124.25427.0.124.255254
12627.0.125.0/2427.0.125.1 to 27.0.125.25427.0.125.255254
12727.0.126.0/2427.0.126.1 to 27.0.126.25427.0.126.255254
12827.0.127.0/2427.0.127.1 to 27.0.127.25427.0.127.255254
12927.0.128.0/2427.0.128.1 to 27.0.128.25427.0.128.255254
13027.0.129.0/2427.0.129.1 to 27.0.129.25427.0.129.255254
13127.0.130.0/2427.0.130.1 to 27.0.130.25427.0.130.255254
13227.0.131.0/2427.0.131.1 to 27.0.131.25427.0.131.255254
13327.0.132.0/2427.0.132.1 to 27.0.132.25427.0.132.255254
13427.0.133.0/2427.0.133.1 to 27.0.133.25427.0.133.255254
13527.0.134.0/2427.0.134.1 to 27.0.134.25427.0.134.255254
13627.0.135.0/2427.0.135.1 to 27.0.135.25427.0.135.255254
13727.0.136.0/2427.0.136.1 to 27.0.136.25427.0.136.255254
13827.0.137.0/2427.0.137.1 to 27.0.137.25427.0.137.255254
13927.0.138.0/2427.0.138.1 to 27.0.138.25427.0.138.255254
14027.0.139.0/2427.0.139.1 to 27.0.139.25427.0.139.255254
14127.0.140.0/2427.0.140.1 to 27.0.140.25427.0.140.255254
14227.0.141.0/2427.0.141.1 to 27.0.141.25427.0.141.255254
14327.0.142.0/2427.0.142.1 to 27.0.142.25427.0.142.255254
14427.0.143.0/2427.0.143.1 to 27.0.143.25427.0.143.255254
14527.0.144.0/2427.0.144.1 to 27.0.144.25427.0.144.255254
14627.0.145.0/2427.0.145.1 to 27.0.145.25427.0.145.255254
14727.0.146.0/2427.0.146.1 to 27.0.146.25427.0.146.255254
14827.0.147.0/2427.0.147.1 to 27.0.147.25427.0.147.255254
14927.0.148.0/2427.0.148.1 to 27.0.148.25427.0.148.255254
15027.0.149.0/2427.0.149.1 to 27.0.149.25427.0.149.255254
15127.0.150.0/2427.0.150.1 to 27.0.150.25427.0.150.255254
15227.0.151.0/2427.0.151.1 to 27.0.151.25427.0.151.255254
15327.0.152.0/2427.0.152.1 to 27.0.152.25427.0.152.255254
15427.0.153.0/2427.0.153.1 to 27.0.153.25427.0.153.255254
15527.0.154.0/2427.0.154.1 to 27.0.154.25427.0.154.255254
15627.0.155.0/2427.0.155.1 to 27.0.155.25427.0.155.255254
15727.0.156.0/2427.0.156.1 to 27.0.156.25427.0.156.255254
15827.0.157.0/2427.0.157.1 to 27.0.157.25427.0.157.255254
15927.0.158.0/2427.0.158.1 to 27.0.158.25427.0.158.255254
16027.0.159.0/2427.0.159.1 to 27.0.159.25427.0.159.255254
16127.0.160.0/2427.0.160.1 to 27.0.160.25427.0.160.255254
16227.0.161.0/2427.0.161.1 to 27.0.161.25427.0.161.255254
16327.0.162.0/2427.0.162.1 to 27.0.162.25427.0.162.255254
16427.0.163.0/2427.0.163.1 to 27.0.163.25427.0.163.255254
16527.0.164.0/2427.0.164.1 to 27.0.164.25427.0.164.255254
16627.0.165.0/2427.0.165.1 to 27.0.165.25427.0.165.255254
16727.0.166.0/2427.0.166.1 to 27.0.166.25427.0.166.255254
16827.0.167.0/2427.0.167.1 to 27.0.167.25427.0.167.255254
16927.0.168.0/2427.0.168.1 to 27.0.168.25427.0.168.255254
17027.0.169.0/2427.0.169.1 to 27.0.169.25427.0.169.255254
17127.0.170.0/2427.0.170.1 to 27.0.170.25427.0.170.255254
17227.0.171.0/2427.0.171.1 to 27.0.171.25427.0.171.255254
17327.0.172.0/2427.0.172.1 to 27.0.172.25427.0.172.255254
17427.0.173.0/2427.0.173.1 to 27.0.173.25427.0.173.255254
17527.0.174.0/2427.0.174.1 to 27.0.174.25427.0.174.255254
17627.0.175.0/2427.0.175.1 to 27.0.175.25427.0.175.255254
17727.0.176.0/2427.0.176.1 to 27.0.176.25427.0.176.255254
17827.0.177.0/2427.0.177.1 to 27.0.177.25427.0.177.255254
17927.0.178.0/2427.0.178.1 to 27.0.178.25427.0.178.255254
18027.0.179.0/2427.0.179.1 to 27.0.179.25427.0.179.255254
18127.0.180.0/2427.0.180.1 to 27.0.180.25427.0.180.255254
18227.0.181.0/2427.0.181.1 to 27.0.181.25427.0.181.255254
18327.0.182.0/2427.0.182.1 to 27.0.182.25427.0.182.255254
18427.0.183.0/2427.0.183.1 to 27.0.183.25427.0.183.255254
18527.0.184.0/2427.0.184.1 to 27.0.184.25427.0.184.255254
18627.0.185.0/2427.0.185.1 to 27.0.185.25427.0.185.255254
18727.0.186.0/2427.0.186.1 to 27.0.186.25427.0.186.255254
18827.0.187.0/2427.0.187.1 to 27.0.187.25427.0.187.255254
18927.0.188.0/2427.0.188.1 to 27.0.188.25427.0.188.255254
19027.0.189.0/2427.0.189.1 to 27.0.189.25427.0.189.255254
19127.0.190.0/2427.0.190.1 to 27.0.190.25427.0.190.255254
19227.0.191.0/2427.0.191.1 to 27.0.191.25427.0.191.255254
19327.0.192.0/2427.0.192.1 to 27.0.192.25427.0.192.255254
19427.0.193.0/2427.0.193.1 to 27.0.193.25427.0.193.255254
19527.0.194.0/2427.0.194.1 to 27.0.194.25427.0.194.255254
19627.0.195.0/2427.0.195.1 to 27.0.195.25427.0.195.255254
19727.0.196.0/2427.0.196.1 to 27.0.196.25427.0.196.255254
19827.0.197.0/2427.0.197.1 to 27.0.197.25427.0.197.255254
19927.0.198.0/2427.0.198.1 to 27.0.198.25427.0.198.255254
20027.0.199.0/2427.0.199.1 to 27.0.199.25427.0.199.255254
20127.0.200.0/2427.0.200.1 to 27.0.200.25427.0.200.255254
20227.0.201.0/2427.0.201.1 to 27.0.201.25427.0.201.255254
20327.0.202.0/2427.0.202.1 to 27.0.202.25427.0.202.255254
20427.0.203.0/2427.0.203.1 to 27.0.203.25427.0.203.255254
20527.0.204.0/2427.0.204.1 to 27.0.204.25427.0.204.255254
20627.0.205.0/2427.0.205.1 to 27.0.205.25427.0.205.255254
20727.0.206.0/2427.0.206.1 to 27.0.206.25427.0.206.255254
20827.0.207.0/2427.0.207.1 to 27.0.207.25427.0.207.255254
20927.0.208.0/2427.0.208.1 to 27.0.208.25427.0.208.255254
21027.0.209.0/2427.0.209.1 to 27.0.209.25427.0.209.255254
21127.0.210.0/2427.0.210.1 to 27.0.210.25427.0.210.255254
21227.0.211.0/2427.0.211.1 to 27.0.211.25427.0.211.255254
21327.0.212.0/2427.0.212.1 to 27.0.212.25427.0.212.255254
21427.0.213.0/2427.0.213.1 to 27.0.213.25427.0.213.255254
21527.0.214.0/2427.0.214.1 to 27.0.214.25427.0.214.255254
21627.0.215.0/2427.0.215.1 to 27.0.215.25427.0.215.255254
21727.0.216.0/2427.0.216.1 to 27.0.216.25427.0.216.255254
21827.0.217.0/2427.0.217.1 to 27.0.217.25427.0.217.255254
21927.0.218.0/2427.0.218.1 to 27.0.218.25427.0.218.255254
22027.0.219.0/2427.0.219.1 to 27.0.219.25427.0.219.255254
22127.0.220.0/2427.0.220.1 to 27.0.220.25427.0.220.255254
22227.0.221.0/2427.0.221.1 to 27.0.221.25427.0.221.255254
22327.0.222.0/2427.0.222.1 to 27.0.222.25427.0.222.255254
22427.0.223.0/2427.0.223.1 to 27.0.223.25427.0.223.255254
22527.0.224.0/2427.0.224.1 to 27.0.224.25427.0.224.255254
22627.0.225.0/2427.0.225.1 to 27.0.225.25427.0.225.255254
22727.0.226.0/2427.0.226.1 to 27.0.226.25427.0.226.255254
22827.0.227.0/2427.0.227.1 to 27.0.227.25427.0.227.255254
22927.0.228.0/2427.0.228.1 to 27.0.228.25427.0.228.255254
23027.0.229.0/2427.0.229.1 to 27.0.229.25427.0.229.255254
23127.0.230.0/2427.0.230.1 to 27.0.230.25427.0.230.255254
23227.0.231.0/2427.0.231.1 to 27.0.231.25427.0.231.255254
23327.0.232.0/2427.0.232.1 to 27.0.232.25427.0.232.255254
23427.0.233.0/2427.0.233.1 to 27.0.233.25427.0.233.255254
23527.0.234.0/2427.0.234.1 to 27.0.234.25427.0.234.255254
23627.0.235.0/2427.0.235.1 to 27.0.235.25427.0.235.255254
23727.0.236.0/2427.0.236.1 to 27.0.236.25427.0.236.255254
23827.0.237.0/2427.0.237.1 to 27.0.237.25427.0.237.255254
23927.0.238.0/2427.0.238.1 to 27.0.238.25427.0.238.255254
24027.0.239.0/2427.0.239.1 to 27.0.239.25427.0.239.255254
24127.0.240.0/2427.0.240.1 to 27.0.240.25427.0.240.255254
24227.0.241.0/2427.0.241.1 to 27.0.241.25427.0.241.255254
24327.0.242.0/2427.0.242.1 to 27.0.242.25427.0.242.255254
24427.0.243.0/2427.0.243.1 to 27.0.243.25427.0.243.255254
24527.0.244.0/2427.0.244.1 to 27.0.244.25427.0.244.255254
24627.0.245.0/2427.0.245.1 to 27.0.245.25427.0.245.255254
24727.0.246.0/2427.0.246.1 to 27.0.246.25427.0.246.255254
24827.0.247.0/2427.0.247.1 to 27.0.247.25427.0.247.255254
24927.0.248.0/2427.0.248.1 to 27.0.248.25427.0.248.255254
25027.0.249.0/2427.0.249.1 to 27.0.249.25427.0.249.255254
25127.0.250.0/2427.0.250.1 to 27.0.250.25427.0.250.255254
25227.0.251.0/2427.0.251.1 to 27.0.251.25427.0.251.255254
25327.0.252.0/2427.0.252.1 to 27.0.252.25427.0.252.255254
25427.0.253.0/2427.0.253.1 to 27.0.253.25427.0.253.255254
25527.0.254.0/2427.0.254.1 to 27.0.254.25427.0.254.255254
25627.0.255.0/2427.0.255.1 to 27.0.255.25427.0.255.255254

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.