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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.

Network32.64.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
32.64.0.0
Broadcast address
32.127.255.255
First usable
32.64.0.1
Last usable
32.127.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
A (default /8)
As numbers
Hex 20400000 · Integer 541065216 to 545259519
Reverse DNS zones
64.32.in-addr.arpa
65.32.in-addr.arpa
66.32.in-addr.arpa
67.32.in-addr.arpa
68.32.in-addr.arpa
69.32.in-addr.arpa
70.32.in-addr.arpa
71.32.in-addr.arpa
72.32.in-addr.arpa
73.32.in-addr.arpa
74.32.in-addr.arpa
75.32.in-addr.arpa
76.32.in-addr.arpa
77.32.in-addr.arpa
78.32.in-addr.arpa
79.32.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00100000.01000000.00000000.0000000032.64.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00100000.01000000.00000000.0000000032.64.0.0
Broadcast00100000.01111111.11111111.1111111132.127.255.255
Split into smaller subnets/22
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

32.64.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
132.64.0.0/2232.64.0.1 to 32.64.3.25432.64.3.2551,022
232.64.4.0/2232.64.4.1 to 32.64.7.25432.64.7.2551,022
332.64.8.0/2232.64.8.1 to 32.64.11.25432.64.11.2551,022
432.64.12.0/2232.64.12.1 to 32.64.15.25432.64.15.2551,022
532.64.16.0/2232.64.16.1 to 32.64.19.25432.64.19.2551,022
632.64.20.0/2232.64.20.1 to 32.64.23.25432.64.23.2551,022
732.64.24.0/2232.64.24.1 to 32.64.27.25432.64.27.2551,022
832.64.28.0/2232.64.28.1 to 32.64.31.25432.64.31.2551,022
932.64.32.0/2232.64.32.1 to 32.64.35.25432.64.35.2551,022
1032.64.36.0/2232.64.36.1 to 32.64.39.25432.64.39.2551,022
1132.64.40.0/2232.64.40.1 to 32.64.43.25432.64.43.2551,022
1232.64.44.0/2232.64.44.1 to 32.64.47.25432.64.47.2551,022
1332.64.48.0/2232.64.48.1 to 32.64.51.25432.64.51.2551,022
1432.64.52.0/2232.64.52.1 to 32.64.55.25432.64.55.2551,022
1532.64.56.0/2232.64.56.1 to 32.64.59.25432.64.59.2551,022
1632.64.60.0/2232.64.60.1 to 32.64.63.25432.64.63.2551,022
1732.64.64.0/2232.64.64.1 to 32.64.67.25432.64.67.2551,022
1832.64.68.0/2232.64.68.1 to 32.64.71.25432.64.71.2551,022
1932.64.72.0/2232.64.72.1 to 32.64.75.25432.64.75.2551,022
2032.64.76.0/2232.64.76.1 to 32.64.79.25432.64.79.2551,022
2132.64.80.0/2232.64.80.1 to 32.64.83.25432.64.83.2551,022
2232.64.84.0/2232.64.84.1 to 32.64.87.25432.64.87.2551,022
2332.64.88.0/2232.64.88.1 to 32.64.91.25432.64.91.2551,022
2432.64.92.0/2232.64.92.1 to 32.64.95.25432.64.95.2551,022
2532.64.96.0/2232.64.96.1 to 32.64.99.25432.64.99.2551,022
2632.64.100.0/2232.64.100.1 to 32.64.103.25432.64.103.2551,022
2732.64.104.0/2232.64.104.1 to 32.64.107.25432.64.107.2551,022
2832.64.108.0/2232.64.108.1 to 32.64.111.25432.64.111.2551,022
2932.64.112.0/2232.64.112.1 to 32.64.115.25432.64.115.2551,022
3032.64.116.0/2232.64.116.1 to 32.64.119.25432.64.119.2551,022
3132.64.120.0/2232.64.120.1 to 32.64.123.25432.64.123.2551,022
3232.64.124.0/2232.64.124.1 to 32.64.127.25432.64.127.2551,022
3332.64.128.0/2232.64.128.1 to 32.64.131.25432.64.131.2551,022
3432.64.132.0/2232.64.132.1 to 32.64.135.25432.64.135.2551,022
3532.64.136.0/2232.64.136.1 to 32.64.139.25432.64.139.2551,022
3632.64.140.0/2232.64.140.1 to 32.64.143.25432.64.143.2551,022
3732.64.144.0/2232.64.144.1 to 32.64.147.25432.64.147.2551,022
3832.64.148.0/2232.64.148.1 to 32.64.151.25432.64.151.2551,022
3932.64.152.0/2232.64.152.1 to 32.64.155.25432.64.155.2551,022
4032.64.156.0/2232.64.156.1 to 32.64.159.25432.64.159.2551,022
4132.64.160.0/2232.64.160.1 to 32.64.163.25432.64.163.2551,022
4232.64.164.0/2232.64.164.1 to 32.64.167.25432.64.167.2551,022
4332.64.168.0/2232.64.168.1 to 32.64.171.25432.64.171.2551,022
4432.64.172.0/2232.64.172.1 to 32.64.175.25432.64.175.2551,022
4532.64.176.0/2232.64.176.1 to 32.64.179.25432.64.179.2551,022
4632.64.180.0/2232.64.180.1 to 32.64.183.25432.64.183.2551,022
4732.64.184.0/2232.64.184.1 to 32.64.187.25432.64.187.2551,022
4832.64.188.0/2232.64.188.1 to 32.64.191.25432.64.191.2551,022
4932.64.192.0/2232.64.192.1 to 32.64.195.25432.64.195.2551,022
5032.64.196.0/2232.64.196.1 to 32.64.199.25432.64.199.2551,022
5132.64.200.0/2232.64.200.1 to 32.64.203.25432.64.203.2551,022
5232.64.204.0/2232.64.204.1 to 32.64.207.25432.64.207.2551,022
5332.64.208.0/2232.64.208.1 to 32.64.211.25432.64.211.2551,022
5432.64.212.0/2232.64.212.1 to 32.64.215.25432.64.215.2551,022
5532.64.216.0/2232.64.216.1 to 32.64.219.25432.64.219.2551,022
5632.64.220.0/2232.64.220.1 to 32.64.223.25432.64.223.2551,022
5732.64.224.0/2232.64.224.1 to 32.64.227.25432.64.227.2551,022
5832.64.228.0/2232.64.228.1 to 32.64.231.25432.64.231.2551,022
5932.64.232.0/2232.64.232.1 to 32.64.235.25432.64.235.2551,022
6032.64.236.0/2232.64.236.1 to 32.64.239.25432.64.239.2551,022
6132.64.240.0/2232.64.240.1 to 32.64.243.25432.64.243.2551,022
6232.64.244.0/2232.64.244.1 to 32.64.247.25432.64.247.2551,022
6332.64.248.0/2232.64.248.1 to 32.64.251.25432.64.251.2551,022
6432.64.252.0/2232.64.252.1 to 32.64.255.25432.64.255.2551,022
6532.65.0.0/2232.65.0.1 to 32.65.3.25432.65.3.2551,022
6632.65.4.0/2232.65.4.1 to 32.65.7.25432.65.7.2551,022
6732.65.8.0/2232.65.8.1 to 32.65.11.25432.65.11.2551,022
6832.65.12.0/2232.65.12.1 to 32.65.15.25432.65.15.2551,022
6932.65.16.0/2232.65.16.1 to 32.65.19.25432.65.19.2551,022
7032.65.20.0/2232.65.20.1 to 32.65.23.25432.65.23.2551,022
7132.65.24.0/2232.65.24.1 to 32.65.27.25432.65.27.2551,022
7232.65.28.0/2232.65.28.1 to 32.65.31.25432.65.31.2551,022
7332.65.32.0/2232.65.32.1 to 32.65.35.25432.65.35.2551,022
7432.65.36.0/2232.65.36.1 to 32.65.39.25432.65.39.2551,022
7532.65.40.0/2232.65.40.1 to 32.65.43.25432.65.43.2551,022
7632.65.44.0/2232.65.44.1 to 32.65.47.25432.65.47.2551,022
7732.65.48.0/2232.65.48.1 to 32.65.51.25432.65.51.2551,022
7832.65.52.0/2232.65.52.1 to 32.65.55.25432.65.55.2551,022
7932.65.56.0/2232.65.56.1 to 32.65.59.25432.65.59.2551,022
8032.65.60.0/2232.65.60.1 to 32.65.63.25432.65.63.2551,022
8132.65.64.0/2232.65.64.1 to 32.65.67.25432.65.67.2551,022
8232.65.68.0/2232.65.68.1 to 32.65.71.25432.65.71.2551,022
8332.65.72.0/2232.65.72.1 to 32.65.75.25432.65.75.2551,022
8432.65.76.0/2232.65.76.1 to 32.65.79.25432.65.79.2551,022
8532.65.80.0/2232.65.80.1 to 32.65.83.25432.65.83.2551,022
8632.65.84.0/2232.65.84.1 to 32.65.87.25432.65.87.2551,022
8732.65.88.0/2232.65.88.1 to 32.65.91.25432.65.91.2551,022
8832.65.92.0/2232.65.92.1 to 32.65.95.25432.65.95.2551,022
8932.65.96.0/2232.65.96.1 to 32.65.99.25432.65.99.2551,022
9032.65.100.0/2232.65.100.1 to 32.65.103.25432.65.103.2551,022
9132.65.104.0/2232.65.104.1 to 32.65.107.25432.65.107.2551,022
9232.65.108.0/2232.65.108.1 to 32.65.111.25432.65.111.2551,022
9332.65.112.0/2232.65.112.1 to 32.65.115.25432.65.115.2551,022
9432.65.116.0/2232.65.116.1 to 32.65.119.25432.65.119.2551,022
9532.65.120.0/2232.65.120.1 to 32.65.123.25432.65.123.2551,022
9632.65.124.0/2232.65.124.1 to 32.65.127.25432.65.127.2551,022
9732.65.128.0/2232.65.128.1 to 32.65.131.25432.65.131.2551,022
9832.65.132.0/2232.65.132.1 to 32.65.135.25432.65.135.2551,022
9932.65.136.0/2232.65.136.1 to 32.65.139.25432.65.139.2551,022
10032.65.140.0/2232.65.140.1 to 32.65.143.25432.65.143.2551,022
10132.65.144.0/2232.65.144.1 to 32.65.147.25432.65.147.2551,022
10232.65.148.0/2232.65.148.1 to 32.65.151.25432.65.151.2551,022
10332.65.152.0/2232.65.152.1 to 32.65.155.25432.65.155.2551,022
10432.65.156.0/2232.65.156.1 to 32.65.159.25432.65.159.2551,022
10532.65.160.0/2232.65.160.1 to 32.65.163.25432.65.163.2551,022
10632.65.164.0/2232.65.164.1 to 32.65.167.25432.65.167.2551,022
10732.65.168.0/2232.65.168.1 to 32.65.171.25432.65.171.2551,022
10832.65.172.0/2232.65.172.1 to 32.65.175.25432.65.175.2551,022
10932.65.176.0/2232.65.176.1 to 32.65.179.25432.65.179.2551,022
11032.65.180.0/2232.65.180.1 to 32.65.183.25432.65.183.2551,022
11132.65.184.0/2232.65.184.1 to 32.65.187.25432.65.187.2551,022
11232.65.188.0/2232.65.188.1 to 32.65.191.25432.65.191.2551,022
11332.65.192.0/2232.65.192.1 to 32.65.195.25432.65.195.2551,022
11432.65.196.0/2232.65.196.1 to 32.65.199.25432.65.199.2551,022
11532.65.200.0/2232.65.200.1 to 32.65.203.25432.65.203.2551,022
11632.65.204.0/2232.65.204.1 to 32.65.207.25432.65.207.2551,022
11732.65.208.0/2232.65.208.1 to 32.65.211.25432.65.211.2551,022
11832.65.212.0/2232.65.212.1 to 32.65.215.25432.65.215.2551,022
11932.65.216.0/2232.65.216.1 to 32.65.219.25432.65.219.2551,022
12032.65.220.0/2232.65.220.1 to 32.65.223.25432.65.223.2551,022
12132.65.224.0/2232.65.224.1 to 32.65.227.25432.65.227.2551,022
12232.65.228.0/2232.65.228.1 to 32.65.231.25432.65.231.2551,022
12332.65.232.0/2232.65.232.1 to 32.65.235.25432.65.235.2551,022
12432.65.236.0/2232.65.236.1 to 32.65.239.25432.65.239.2551,022
12532.65.240.0/2232.65.240.1 to 32.65.243.25432.65.243.2551,022
12632.65.244.0/2232.65.244.1 to 32.65.247.25432.65.247.2551,022
12732.65.248.0/2232.65.248.1 to 32.65.251.25432.65.251.2551,022
12832.65.252.0/2232.65.252.1 to 32.65.255.25432.65.255.2551,022
12932.66.0.0/2232.66.0.1 to 32.66.3.25432.66.3.2551,022
13032.66.4.0/2232.66.4.1 to 32.66.7.25432.66.7.2551,022
13132.66.8.0/2232.66.8.1 to 32.66.11.25432.66.11.2551,022
13232.66.12.0/2232.66.12.1 to 32.66.15.25432.66.15.2551,022
13332.66.16.0/2232.66.16.1 to 32.66.19.25432.66.19.2551,022
13432.66.20.0/2232.66.20.1 to 32.66.23.25432.66.23.2551,022
13532.66.24.0/2232.66.24.1 to 32.66.27.25432.66.27.2551,022
13632.66.28.0/2232.66.28.1 to 32.66.31.25432.66.31.2551,022
13732.66.32.0/2232.66.32.1 to 32.66.35.25432.66.35.2551,022
13832.66.36.0/2232.66.36.1 to 32.66.39.25432.66.39.2551,022
13932.66.40.0/2232.66.40.1 to 32.66.43.25432.66.43.2551,022
14032.66.44.0/2232.66.44.1 to 32.66.47.25432.66.47.2551,022
14132.66.48.0/2232.66.48.1 to 32.66.51.25432.66.51.2551,022
14232.66.52.0/2232.66.52.1 to 32.66.55.25432.66.55.2551,022
14332.66.56.0/2232.66.56.1 to 32.66.59.25432.66.59.2551,022
14432.66.60.0/2232.66.60.1 to 32.66.63.25432.66.63.2551,022
14532.66.64.0/2232.66.64.1 to 32.66.67.25432.66.67.2551,022
14632.66.68.0/2232.66.68.1 to 32.66.71.25432.66.71.2551,022
14732.66.72.0/2232.66.72.1 to 32.66.75.25432.66.75.2551,022
14832.66.76.0/2232.66.76.1 to 32.66.79.25432.66.79.2551,022
14932.66.80.0/2232.66.80.1 to 32.66.83.25432.66.83.2551,022
15032.66.84.0/2232.66.84.1 to 32.66.87.25432.66.87.2551,022
15132.66.88.0/2232.66.88.1 to 32.66.91.25432.66.91.2551,022
15232.66.92.0/2232.66.92.1 to 32.66.95.25432.66.95.2551,022
15332.66.96.0/2232.66.96.1 to 32.66.99.25432.66.99.2551,022
15432.66.100.0/2232.66.100.1 to 32.66.103.25432.66.103.2551,022
15532.66.104.0/2232.66.104.1 to 32.66.107.25432.66.107.2551,022
15632.66.108.0/2232.66.108.1 to 32.66.111.25432.66.111.2551,022
15732.66.112.0/2232.66.112.1 to 32.66.115.25432.66.115.2551,022
15832.66.116.0/2232.66.116.1 to 32.66.119.25432.66.119.2551,022
15932.66.120.0/2232.66.120.1 to 32.66.123.25432.66.123.2551,022
16032.66.124.0/2232.66.124.1 to 32.66.127.25432.66.127.2551,022
16132.66.128.0/2232.66.128.1 to 32.66.131.25432.66.131.2551,022
16232.66.132.0/2232.66.132.1 to 32.66.135.25432.66.135.2551,022
16332.66.136.0/2232.66.136.1 to 32.66.139.25432.66.139.2551,022
16432.66.140.0/2232.66.140.1 to 32.66.143.25432.66.143.2551,022
16532.66.144.0/2232.66.144.1 to 32.66.147.25432.66.147.2551,022
16632.66.148.0/2232.66.148.1 to 32.66.151.25432.66.151.2551,022
16732.66.152.0/2232.66.152.1 to 32.66.155.25432.66.155.2551,022
16832.66.156.0/2232.66.156.1 to 32.66.159.25432.66.159.2551,022
16932.66.160.0/2232.66.160.1 to 32.66.163.25432.66.163.2551,022
17032.66.164.0/2232.66.164.1 to 32.66.167.25432.66.167.2551,022
17132.66.168.0/2232.66.168.1 to 32.66.171.25432.66.171.2551,022
17232.66.172.0/2232.66.172.1 to 32.66.175.25432.66.175.2551,022
17332.66.176.0/2232.66.176.1 to 32.66.179.25432.66.179.2551,022
17432.66.180.0/2232.66.180.1 to 32.66.183.25432.66.183.2551,022
17532.66.184.0/2232.66.184.1 to 32.66.187.25432.66.187.2551,022
17632.66.188.0/2232.66.188.1 to 32.66.191.25432.66.191.2551,022
17732.66.192.0/2232.66.192.1 to 32.66.195.25432.66.195.2551,022
17832.66.196.0/2232.66.196.1 to 32.66.199.25432.66.199.2551,022
17932.66.200.0/2232.66.200.1 to 32.66.203.25432.66.203.2551,022
18032.66.204.0/2232.66.204.1 to 32.66.207.25432.66.207.2551,022
18132.66.208.0/2232.66.208.1 to 32.66.211.25432.66.211.2551,022
18232.66.212.0/2232.66.212.1 to 32.66.215.25432.66.215.2551,022
18332.66.216.0/2232.66.216.1 to 32.66.219.25432.66.219.2551,022
18432.66.220.0/2232.66.220.1 to 32.66.223.25432.66.223.2551,022
18532.66.224.0/2232.66.224.1 to 32.66.227.25432.66.227.2551,022
18632.66.228.0/2232.66.228.1 to 32.66.231.25432.66.231.2551,022
18732.66.232.0/2232.66.232.1 to 32.66.235.25432.66.235.2551,022
18832.66.236.0/2232.66.236.1 to 32.66.239.25432.66.239.2551,022
18932.66.240.0/2232.66.240.1 to 32.66.243.25432.66.243.2551,022
19032.66.244.0/2232.66.244.1 to 32.66.247.25432.66.247.2551,022
19132.66.248.0/2232.66.248.1 to 32.66.251.25432.66.251.2551,022
19232.66.252.0/2232.66.252.1 to 32.66.255.25432.66.255.2551,022
19332.67.0.0/2232.67.0.1 to 32.67.3.25432.67.3.2551,022
19432.67.4.0/2232.67.4.1 to 32.67.7.25432.67.7.2551,022
19532.67.8.0/2232.67.8.1 to 32.67.11.25432.67.11.2551,022
19632.67.12.0/2232.67.12.1 to 32.67.15.25432.67.15.2551,022
19732.67.16.0/2232.67.16.1 to 32.67.19.25432.67.19.2551,022
19832.67.20.0/2232.67.20.1 to 32.67.23.25432.67.23.2551,022
19932.67.24.0/2232.67.24.1 to 32.67.27.25432.67.27.2551,022
20032.67.28.0/2232.67.28.1 to 32.67.31.25432.67.31.2551,022
20132.67.32.0/2232.67.32.1 to 32.67.35.25432.67.35.2551,022
20232.67.36.0/2232.67.36.1 to 32.67.39.25432.67.39.2551,022
20332.67.40.0/2232.67.40.1 to 32.67.43.25432.67.43.2551,022
20432.67.44.0/2232.67.44.1 to 32.67.47.25432.67.47.2551,022
20532.67.48.0/2232.67.48.1 to 32.67.51.25432.67.51.2551,022
20632.67.52.0/2232.67.52.1 to 32.67.55.25432.67.55.2551,022
20732.67.56.0/2232.67.56.1 to 32.67.59.25432.67.59.2551,022
20832.67.60.0/2232.67.60.1 to 32.67.63.25432.67.63.2551,022
20932.67.64.0/2232.67.64.1 to 32.67.67.25432.67.67.2551,022
21032.67.68.0/2232.67.68.1 to 32.67.71.25432.67.71.2551,022
21132.67.72.0/2232.67.72.1 to 32.67.75.25432.67.75.2551,022
21232.67.76.0/2232.67.76.1 to 32.67.79.25432.67.79.2551,022
21332.67.80.0/2232.67.80.1 to 32.67.83.25432.67.83.2551,022
21432.67.84.0/2232.67.84.1 to 32.67.87.25432.67.87.2551,022
21532.67.88.0/2232.67.88.1 to 32.67.91.25432.67.91.2551,022
21632.67.92.0/2232.67.92.1 to 32.67.95.25432.67.95.2551,022
21732.67.96.0/2232.67.96.1 to 32.67.99.25432.67.99.2551,022
21832.67.100.0/2232.67.100.1 to 32.67.103.25432.67.103.2551,022
21932.67.104.0/2232.67.104.1 to 32.67.107.25432.67.107.2551,022
22032.67.108.0/2232.67.108.1 to 32.67.111.25432.67.111.2551,022
22132.67.112.0/2232.67.112.1 to 32.67.115.25432.67.115.2551,022
22232.67.116.0/2232.67.116.1 to 32.67.119.25432.67.119.2551,022
22332.67.120.0/2232.67.120.1 to 32.67.123.25432.67.123.2551,022
22432.67.124.0/2232.67.124.1 to 32.67.127.25432.67.127.2551,022
22532.67.128.0/2232.67.128.1 to 32.67.131.25432.67.131.2551,022
22632.67.132.0/2232.67.132.1 to 32.67.135.25432.67.135.2551,022
22732.67.136.0/2232.67.136.1 to 32.67.139.25432.67.139.2551,022
22832.67.140.0/2232.67.140.1 to 32.67.143.25432.67.143.2551,022
22932.67.144.0/2232.67.144.1 to 32.67.147.25432.67.147.2551,022
23032.67.148.0/2232.67.148.1 to 32.67.151.25432.67.151.2551,022
23132.67.152.0/2232.67.152.1 to 32.67.155.25432.67.155.2551,022
23232.67.156.0/2232.67.156.1 to 32.67.159.25432.67.159.2551,022
23332.67.160.0/2232.67.160.1 to 32.67.163.25432.67.163.2551,022
23432.67.164.0/2232.67.164.1 to 32.67.167.25432.67.167.2551,022
23532.67.168.0/2232.67.168.1 to 32.67.171.25432.67.171.2551,022
23632.67.172.0/2232.67.172.1 to 32.67.175.25432.67.175.2551,022
23732.67.176.0/2232.67.176.1 to 32.67.179.25432.67.179.2551,022
23832.67.180.0/2232.67.180.1 to 32.67.183.25432.67.183.2551,022
23932.67.184.0/2232.67.184.1 to 32.67.187.25432.67.187.2551,022
24032.67.188.0/2232.67.188.1 to 32.67.191.25432.67.191.2551,022
24132.67.192.0/2232.67.192.1 to 32.67.195.25432.67.195.2551,022
24232.67.196.0/2232.67.196.1 to 32.67.199.25432.67.199.2551,022
24332.67.200.0/2232.67.200.1 to 32.67.203.25432.67.203.2551,022
24432.67.204.0/2232.67.204.1 to 32.67.207.25432.67.207.2551,022
24532.67.208.0/2232.67.208.1 to 32.67.211.25432.67.211.2551,022
24632.67.212.0/2232.67.212.1 to 32.67.215.25432.67.215.2551,022
24732.67.216.0/2232.67.216.1 to 32.67.219.25432.67.219.2551,022
24832.67.220.0/2232.67.220.1 to 32.67.223.25432.67.223.2551,022
24932.67.224.0/2232.67.224.1 to 32.67.227.25432.67.227.2551,022
25032.67.228.0/2232.67.228.1 to 32.67.231.25432.67.231.2551,022
25132.67.232.0/2232.67.232.1 to 32.67.235.25432.67.235.2551,022
25232.67.236.0/2232.67.236.1 to 32.67.239.25432.67.239.2551,022
25332.67.240.0/2232.67.240.1 to 32.67.243.25432.67.243.2551,022
25432.67.244.0/2232.67.244.1 to 32.67.247.25432.67.247.2551,022
25532.67.248.0/2232.67.248.1 to 32.67.251.25432.67.251.2551,022
25632.67.252.0/2232.67.252.1 to 32.67.255.25432.67.255.2551,022

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.