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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.

Network32.136.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
32.136.0.0
Broadcast address
32.143.255.255
First usable
32.136.0.1
Last usable
32.143.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 20880000 · Integer 545783808 to 546308095
Reverse DNS zones
136.32.in-addr.arpa
137.32.in-addr.arpa
138.32.in-addr.arpa
139.32.in-addr.arpa
140.32.in-addr.arpa
141.32.in-addr.arpa
142.32.in-addr.arpa
143.32.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00100000.10001000.00000000.0000000032.136.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network00100000.10001000.00000000.0000000032.136.0.0
Broadcast00100000.10001111.11111111.1111111132.143.255.255
Split into smaller subnets/24
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

32.136.0.0/13 makes 2,048 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
132.136.0.0/2432.136.0.1 to 32.136.0.25432.136.0.255254
232.136.1.0/2432.136.1.1 to 32.136.1.25432.136.1.255254
332.136.2.0/2432.136.2.1 to 32.136.2.25432.136.2.255254
432.136.3.0/2432.136.3.1 to 32.136.3.25432.136.3.255254
532.136.4.0/2432.136.4.1 to 32.136.4.25432.136.4.255254
632.136.5.0/2432.136.5.1 to 32.136.5.25432.136.5.255254
732.136.6.0/2432.136.6.1 to 32.136.6.25432.136.6.255254
832.136.7.0/2432.136.7.1 to 32.136.7.25432.136.7.255254
932.136.8.0/2432.136.8.1 to 32.136.8.25432.136.8.255254
1032.136.9.0/2432.136.9.1 to 32.136.9.25432.136.9.255254
1132.136.10.0/2432.136.10.1 to 32.136.10.25432.136.10.255254
1232.136.11.0/2432.136.11.1 to 32.136.11.25432.136.11.255254
1332.136.12.0/2432.136.12.1 to 32.136.12.25432.136.12.255254
1432.136.13.0/2432.136.13.1 to 32.136.13.25432.136.13.255254
1532.136.14.0/2432.136.14.1 to 32.136.14.25432.136.14.255254
1632.136.15.0/2432.136.15.1 to 32.136.15.25432.136.15.255254
1732.136.16.0/2432.136.16.1 to 32.136.16.25432.136.16.255254
1832.136.17.0/2432.136.17.1 to 32.136.17.25432.136.17.255254
1932.136.18.0/2432.136.18.1 to 32.136.18.25432.136.18.255254
2032.136.19.0/2432.136.19.1 to 32.136.19.25432.136.19.255254
2132.136.20.0/2432.136.20.1 to 32.136.20.25432.136.20.255254
2232.136.21.0/2432.136.21.1 to 32.136.21.25432.136.21.255254
2332.136.22.0/2432.136.22.1 to 32.136.22.25432.136.22.255254
2432.136.23.0/2432.136.23.1 to 32.136.23.25432.136.23.255254
2532.136.24.0/2432.136.24.1 to 32.136.24.25432.136.24.255254
2632.136.25.0/2432.136.25.1 to 32.136.25.25432.136.25.255254
2732.136.26.0/2432.136.26.1 to 32.136.26.25432.136.26.255254
2832.136.27.0/2432.136.27.1 to 32.136.27.25432.136.27.255254
2932.136.28.0/2432.136.28.1 to 32.136.28.25432.136.28.255254
3032.136.29.0/2432.136.29.1 to 32.136.29.25432.136.29.255254
3132.136.30.0/2432.136.30.1 to 32.136.30.25432.136.30.255254
3232.136.31.0/2432.136.31.1 to 32.136.31.25432.136.31.255254
3332.136.32.0/2432.136.32.1 to 32.136.32.25432.136.32.255254
3432.136.33.0/2432.136.33.1 to 32.136.33.25432.136.33.255254
3532.136.34.0/2432.136.34.1 to 32.136.34.25432.136.34.255254
3632.136.35.0/2432.136.35.1 to 32.136.35.25432.136.35.255254
3732.136.36.0/2432.136.36.1 to 32.136.36.25432.136.36.255254
3832.136.37.0/2432.136.37.1 to 32.136.37.25432.136.37.255254
3932.136.38.0/2432.136.38.1 to 32.136.38.25432.136.38.255254
4032.136.39.0/2432.136.39.1 to 32.136.39.25432.136.39.255254
4132.136.40.0/2432.136.40.1 to 32.136.40.25432.136.40.255254
4232.136.41.0/2432.136.41.1 to 32.136.41.25432.136.41.255254
4332.136.42.0/2432.136.42.1 to 32.136.42.25432.136.42.255254
4432.136.43.0/2432.136.43.1 to 32.136.43.25432.136.43.255254
4532.136.44.0/2432.136.44.1 to 32.136.44.25432.136.44.255254
4632.136.45.0/2432.136.45.1 to 32.136.45.25432.136.45.255254
4732.136.46.0/2432.136.46.1 to 32.136.46.25432.136.46.255254
4832.136.47.0/2432.136.47.1 to 32.136.47.25432.136.47.255254
4932.136.48.0/2432.136.48.1 to 32.136.48.25432.136.48.255254
5032.136.49.0/2432.136.49.1 to 32.136.49.25432.136.49.255254
5132.136.50.0/2432.136.50.1 to 32.136.50.25432.136.50.255254
5232.136.51.0/2432.136.51.1 to 32.136.51.25432.136.51.255254
5332.136.52.0/2432.136.52.1 to 32.136.52.25432.136.52.255254
5432.136.53.0/2432.136.53.1 to 32.136.53.25432.136.53.255254
5532.136.54.0/2432.136.54.1 to 32.136.54.25432.136.54.255254
5632.136.55.0/2432.136.55.1 to 32.136.55.25432.136.55.255254
5732.136.56.0/2432.136.56.1 to 32.136.56.25432.136.56.255254
5832.136.57.0/2432.136.57.1 to 32.136.57.25432.136.57.255254
5932.136.58.0/2432.136.58.1 to 32.136.58.25432.136.58.255254
6032.136.59.0/2432.136.59.1 to 32.136.59.25432.136.59.255254
6132.136.60.0/2432.136.60.1 to 32.136.60.25432.136.60.255254
6232.136.61.0/2432.136.61.1 to 32.136.61.25432.136.61.255254
6332.136.62.0/2432.136.62.1 to 32.136.62.25432.136.62.255254
6432.136.63.0/2432.136.63.1 to 32.136.63.25432.136.63.255254
6532.136.64.0/2432.136.64.1 to 32.136.64.25432.136.64.255254
6632.136.65.0/2432.136.65.1 to 32.136.65.25432.136.65.255254
6732.136.66.0/2432.136.66.1 to 32.136.66.25432.136.66.255254
6832.136.67.0/2432.136.67.1 to 32.136.67.25432.136.67.255254
6932.136.68.0/2432.136.68.1 to 32.136.68.25432.136.68.255254
7032.136.69.0/2432.136.69.1 to 32.136.69.25432.136.69.255254
7132.136.70.0/2432.136.70.1 to 32.136.70.25432.136.70.255254
7232.136.71.0/2432.136.71.1 to 32.136.71.25432.136.71.255254
7332.136.72.0/2432.136.72.1 to 32.136.72.25432.136.72.255254
7432.136.73.0/2432.136.73.1 to 32.136.73.25432.136.73.255254
7532.136.74.0/2432.136.74.1 to 32.136.74.25432.136.74.255254
7632.136.75.0/2432.136.75.1 to 32.136.75.25432.136.75.255254
7732.136.76.0/2432.136.76.1 to 32.136.76.25432.136.76.255254
7832.136.77.0/2432.136.77.1 to 32.136.77.25432.136.77.255254
7932.136.78.0/2432.136.78.1 to 32.136.78.25432.136.78.255254
8032.136.79.0/2432.136.79.1 to 32.136.79.25432.136.79.255254
8132.136.80.0/2432.136.80.1 to 32.136.80.25432.136.80.255254
8232.136.81.0/2432.136.81.1 to 32.136.81.25432.136.81.255254
8332.136.82.0/2432.136.82.1 to 32.136.82.25432.136.82.255254
8432.136.83.0/2432.136.83.1 to 32.136.83.25432.136.83.255254
8532.136.84.0/2432.136.84.1 to 32.136.84.25432.136.84.255254
8632.136.85.0/2432.136.85.1 to 32.136.85.25432.136.85.255254
8732.136.86.0/2432.136.86.1 to 32.136.86.25432.136.86.255254
8832.136.87.0/2432.136.87.1 to 32.136.87.25432.136.87.255254
8932.136.88.0/2432.136.88.1 to 32.136.88.25432.136.88.255254
9032.136.89.0/2432.136.89.1 to 32.136.89.25432.136.89.255254
9132.136.90.0/2432.136.90.1 to 32.136.90.25432.136.90.255254
9232.136.91.0/2432.136.91.1 to 32.136.91.25432.136.91.255254
9332.136.92.0/2432.136.92.1 to 32.136.92.25432.136.92.255254
9432.136.93.0/2432.136.93.1 to 32.136.93.25432.136.93.255254
9532.136.94.0/2432.136.94.1 to 32.136.94.25432.136.94.255254
9632.136.95.0/2432.136.95.1 to 32.136.95.25432.136.95.255254
9732.136.96.0/2432.136.96.1 to 32.136.96.25432.136.96.255254
9832.136.97.0/2432.136.97.1 to 32.136.97.25432.136.97.255254
9932.136.98.0/2432.136.98.1 to 32.136.98.25432.136.98.255254
10032.136.99.0/2432.136.99.1 to 32.136.99.25432.136.99.255254
10132.136.100.0/2432.136.100.1 to 32.136.100.25432.136.100.255254
10232.136.101.0/2432.136.101.1 to 32.136.101.25432.136.101.255254
10332.136.102.0/2432.136.102.1 to 32.136.102.25432.136.102.255254
10432.136.103.0/2432.136.103.1 to 32.136.103.25432.136.103.255254
10532.136.104.0/2432.136.104.1 to 32.136.104.25432.136.104.255254
10632.136.105.0/2432.136.105.1 to 32.136.105.25432.136.105.255254
10732.136.106.0/2432.136.106.1 to 32.136.106.25432.136.106.255254
10832.136.107.0/2432.136.107.1 to 32.136.107.25432.136.107.255254
10932.136.108.0/2432.136.108.1 to 32.136.108.25432.136.108.255254
11032.136.109.0/2432.136.109.1 to 32.136.109.25432.136.109.255254
11132.136.110.0/2432.136.110.1 to 32.136.110.25432.136.110.255254
11232.136.111.0/2432.136.111.1 to 32.136.111.25432.136.111.255254
11332.136.112.0/2432.136.112.1 to 32.136.112.25432.136.112.255254
11432.136.113.0/2432.136.113.1 to 32.136.113.25432.136.113.255254
11532.136.114.0/2432.136.114.1 to 32.136.114.25432.136.114.255254
11632.136.115.0/2432.136.115.1 to 32.136.115.25432.136.115.255254
11732.136.116.0/2432.136.116.1 to 32.136.116.25432.136.116.255254
11832.136.117.0/2432.136.117.1 to 32.136.117.25432.136.117.255254
11932.136.118.0/2432.136.118.1 to 32.136.118.25432.136.118.255254
12032.136.119.0/2432.136.119.1 to 32.136.119.25432.136.119.255254
12132.136.120.0/2432.136.120.1 to 32.136.120.25432.136.120.255254
12232.136.121.0/2432.136.121.1 to 32.136.121.25432.136.121.255254
12332.136.122.0/2432.136.122.1 to 32.136.122.25432.136.122.255254
12432.136.123.0/2432.136.123.1 to 32.136.123.25432.136.123.255254
12532.136.124.0/2432.136.124.1 to 32.136.124.25432.136.124.255254
12632.136.125.0/2432.136.125.1 to 32.136.125.25432.136.125.255254
12732.136.126.0/2432.136.126.1 to 32.136.126.25432.136.126.255254
12832.136.127.0/2432.136.127.1 to 32.136.127.25432.136.127.255254
12932.136.128.0/2432.136.128.1 to 32.136.128.25432.136.128.255254
13032.136.129.0/2432.136.129.1 to 32.136.129.25432.136.129.255254
13132.136.130.0/2432.136.130.1 to 32.136.130.25432.136.130.255254
13232.136.131.0/2432.136.131.1 to 32.136.131.25432.136.131.255254
13332.136.132.0/2432.136.132.1 to 32.136.132.25432.136.132.255254
13432.136.133.0/2432.136.133.1 to 32.136.133.25432.136.133.255254
13532.136.134.0/2432.136.134.1 to 32.136.134.25432.136.134.255254
13632.136.135.0/2432.136.135.1 to 32.136.135.25432.136.135.255254
13732.136.136.0/2432.136.136.1 to 32.136.136.25432.136.136.255254
13832.136.137.0/2432.136.137.1 to 32.136.137.25432.136.137.255254
13932.136.138.0/2432.136.138.1 to 32.136.138.25432.136.138.255254
14032.136.139.0/2432.136.139.1 to 32.136.139.25432.136.139.255254
14132.136.140.0/2432.136.140.1 to 32.136.140.25432.136.140.255254
14232.136.141.0/2432.136.141.1 to 32.136.141.25432.136.141.255254
14332.136.142.0/2432.136.142.1 to 32.136.142.25432.136.142.255254
14432.136.143.0/2432.136.143.1 to 32.136.143.25432.136.143.255254
14532.136.144.0/2432.136.144.1 to 32.136.144.25432.136.144.255254
14632.136.145.0/2432.136.145.1 to 32.136.145.25432.136.145.255254
14732.136.146.0/2432.136.146.1 to 32.136.146.25432.136.146.255254
14832.136.147.0/2432.136.147.1 to 32.136.147.25432.136.147.255254
14932.136.148.0/2432.136.148.1 to 32.136.148.25432.136.148.255254
15032.136.149.0/2432.136.149.1 to 32.136.149.25432.136.149.255254
15132.136.150.0/2432.136.150.1 to 32.136.150.25432.136.150.255254
15232.136.151.0/2432.136.151.1 to 32.136.151.25432.136.151.255254
15332.136.152.0/2432.136.152.1 to 32.136.152.25432.136.152.255254
15432.136.153.0/2432.136.153.1 to 32.136.153.25432.136.153.255254
15532.136.154.0/2432.136.154.1 to 32.136.154.25432.136.154.255254
15632.136.155.0/2432.136.155.1 to 32.136.155.25432.136.155.255254
15732.136.156.0/2432.136.156.1 to 32.136.156.25432.136.156.255254
15832.136.157.0/2432.136.157.1 to 32.136.157.25432.136.157.255254
15932.136.158.0/2432.136.158.1 to 32.136.158.25432.136.158.255254
16032.136.159.0/2432.136.159.1 to 32.136.159.25432.136.159.255254
16132.136.160.0/2432.136.160.1 to 32.136.160.25432.136.160.255254
16232.136.161.0/2432.136.161.1 to 32.136.161.25432.136.161.255254
16332.136.162.0/2432.136.162.1 to 32.136.162.25432.136.162.255254
16432.136.163.0/2432.136.163.1 to 32.136.163.25432.136.163.255254
16532.136.164.0/2432.136.164.1 to 32.136.164.25432.136.164.255254
16632.136.165.0/2432.136.165.1 to 32.136.165.25432.136.165.255254
16732.136.166.0/2432.136.166.1 to 32.136.166.25432.136.166.255254
16832.136.167.0/2432.136.167.1 to 32.136.167.25432.136.167.255254
16932.136.168.0/2432.136.168.1 to 32.136.168.25432.136.168.255254
17032.136.169.0/2432.136.169.1 to 32.136.169.25432.136.169.255254
17132.136.170.0/2432.136.170.1 to 32.136.170.25432.136.170.255254
17232.136.171.0/2432.136.171.1 to 32.136.171.25432.136.171.255254
17332.136.172.0/2432.136.172.1 to 32.136.172.25432.136.172.255254
17432.136.173.0/2432.136.173.1 to 32.136.173.25432.136.173.255254
17532.136.174.0/2432.136.174.1 to 32.136.174.25432.136.174.255254
17632.136.175.0/2432.136.175.1 to 32.136.175.25432.136.175.255254
17732.136.176.0/2432.136.176.1 to 32.136.176.25432.136.176.255254
17832.136.177.0/2432.136.177.1 to 32.136.177.25432.136.177.255254
17932.136.178.0/2432.136.178.1 to 32.136.178.25432.136.178.255254
18032.136.179.0/2432.136.179.1 to 32.136.179.25432.136.179.255254
18132.136.180.0/2432.136.180.1 to 32.136.180.25432.136.180.255254
18232.136.181.0/2432.136.181.1 to 32.136.181.25432.136.181.255254
18332.136.182.0/2432.136.182.1 to 32.136.182.25432.136.182.255254
18432.136.183.0/2432.136.183.1 to 32.136.183.25432.136.183.255254
18532.136.184.0/2432.136.184.1 to 32.136.184.25432.136.184.255254
18632.136.185.0/2432.136.185.1 to 32.136.185.25432.136.185.255254
18732.136.186.0/2432.136.186.1 to 32.136.186.25432.136.186.255254
18832.136.187.0/2432.136.187.1 to 32.136.187.25432.136.187.255254
18932.136.188.0/2432.136.188.1 to 32.136.188.25432.136.188.255254
19032.136.189.0/2432.136.189.1 to 32.136.189.25432.136.189.255254
19132.136.190.0/2432.136.190.1 to 32.136.190.25432.136.190.255254
19232.136.191.0/2432.136.191.1 to 32.136.191.25432.136.191.255254
19332.136.192.0/2432.136.192.1 to 32.136.192.25432.136.192.255254
19432.136.193.0/2432.136.193.1 to 32.136.193.25432.136.193.255254
19532.136.194.0/2432.136.194.1 to 32.136.194.25432.136.194.255254
19632.136.195.0/2432.136.195.1 to 32.136.195.25432.136.195.255254
19732.136.196.0/2432.136.196.1 to 32.136.196.25432.136.196.255254
19832.136.197.0/2432.136.197.1 to 32.136.197.25432.136.197.255254
19932.136.198.0/2432.136.198.1 to 32.136.198.25432.136.198.255254
20032.136.199.0/2432.136.199.1 to 32.136.199.25432.136.199.255254
20132.136.200.0/2432.136.200.1 to 32.136.200.25432.136.200.255254
20232.136.201.0/2432.136.201.1 to 32.136.201.25432.136.201.255254
20332.136.202.0/2432.136.202.1 to 32.136.202.25432.136.202.255254
20432.136.203.0/2432.136.203.1 to 32.136.203.25432.136.203.255254
20532.136.204.0/2432.136.204.1 to 32.136.204.25432.136.204.255254
20632.136.205.0/2432.136.205.1 to 32.136.205.25432.136.205.255254
20732.136.206.0/2432.136.206.1 to 32.136.206.25432.136.206.255254
20832.136.207.0/2432.136.207.1 to 32.136.207.25432.136.207.255254
20932.136.208.0/2432.136.208.1 to 32.136.208.25432.136.208.255254
21032.136.209.0/2432.136.209.1 to 32.136.209.25432.136.209.255254
21132.136.210.0/2432.136.210.1 to 32.136.210.25432.136.210.255254
21232.136.211.0/2432.136.211.1 to 32.136.211.25432.136.211.255254
21332.136.212.0/2432.136.212.1 to 32.136.212.25432.136.212.255254
21432.136.213.0/2432.136.213.1 to 32.136.213.25432.136.213.255254
21532.136.214.0/2432.136.214.1 to 32.136.214.25432.136.214.255254
21632.136.215.0/2432.136.215.1 to 32.136.215.25432.136.215.255254
21732.136.216.0/2432.136.216.1 to 32.136.216.25432.136.216.255254
21832.136.217.0/2432.136.217.1 to 32.136.217.25432.136.217.255254
21932.136.218.0/2432.136.218.1 to 32.136.218.25432.136.218.255254
22032.136.219.0/2432.136.219.1 to 32.136.219.25432.136.219.255254
22132.136.220.0/2432.136.220.1 to 32.136.220.25432.136.220.255254
22232.136.221.0/2432.136.221.1 to 32.136.221.25432.136.221.255254
22332.136.222.0/2432.136.222.1 to 32.136.222.25432.136.222.255254
22432.136.223.0/2432.136.223.1 to 32.136.223.25432.136.223.255254
22532.136.224.0/2432.136.224.1 to 32.136.224.25432.136.224.255254
22632.136.225.0/2432.136.225.1 to 32.136.225.25432.136.225.255254
22732.136.226.0/2432.136.226.1 to 32.136.226.25432.136.226.255254
22832.136.227.0/2432.136.227.1 to 32.136.227.25432.136.227.255254
22932.136.228.0/2432.136.228.1 to 32.136.228.25432.136.228.255254
23032.136.229.0/2432.136.229.1 to 32.136.229.25432.136.229.255254
23132.136.230.0/2432.136.230.1 to 32.136.230.25432.136.230.255254
23232.136.231.0/2432.136.231.1 to 32.136.231.25432.136.231.255254
23332.136.232.0/2432.136.232.1 to 32.136.232.25432.136.232.255254
23432.136.233.0/2432.136.233.1 to 32.136.233.25432.136.233.255254
23532.136.234.0/2432.136.234.1 to 32.136.234.25432.136.234.255254
23632.136.235.0/2432.136.235.1 to 32.136.235.25432.136.235.255254
23732.136.236.0/2432.136.236.1 to 32.136.236.25432.136.236.255254
23832.136.237.0/2432.136.237.1 to 32.136.237.25432.136.237.255254
23932.136.238.0/2432.136.238.1 to 32.136.238.25432.136.238.255254
24032.136.239.0/2432.136.239.1 to 32.136.239.25432.136.239.255254
24132.136.240.0/2432.136.240.1 to 32.136.240.25432.136.240.255254
24232.136.241.0/2432.136.241.1 to 32.136.241.25432.136.241.255254
24332.136.242.0/2432.136.242.1 to 32.136.242.25432.136.242.255254
24432.136.243.0/2432.136.243.1 to 32.136.243.25432.136.243.255254
24532.136.244.0/2432.136.244.1 to 32.136.244.25432.136.244.255254
24632.136.245.0/2432.136.245.1 to 32.136.245.25432.136.245.255254
24732.136.246.0/2432.136.246.1 to 32.136.246.25432.136.246.255254
24832.136.247.0/2432.136.247.1 to 32.136.247.25432.136.247.255254
24932.136.248.0/2432.136.248.1 to 32.136.248.25432.136.248.255254
25032.136.249.0/2432.136.249.1 to 32.136.249.25432.136.249.255254
25132.136.250.0/2432.136.250.1 to 32.136.250.25432.136.250.255254
25232.136.251.0/2432.136.251.1 to 32.136.251.25432.136.251.255254
25332.136.252.0/2432.136.252.1 to 32.136.252.25432.136.252.255254
25432.136.253.0/2432.136.253.1 to 32.136.253.25432.136.253.255254
25532.136.254.0/2432.136.254.1 to 32.136.254.25432.136.254.255254
25632.136.255.0/2432.136.255.1 to 32.136.255.25432.136.255.255254

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.