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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.

Network32.0.0.0/5
Usable hosts134,217,726
Subnet mask248.0.0.0
Addresses134,217,728
Network address
32.0.0.0
Broadcast address
39.255.255.255
First usable
32.0.0.1
Last usable
39.255.255.254
Usable hosts
134,217,726 (134,217,728 less the network and broadcast addresses)
Subnet mask
248.0.0.0
Wildcard mask
7.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/5
Type
Public public
Old class
A (default /8)
As numbers
Hex 20000000 · Integer 536870912 to 671088639
Reverse DNS zones
32.in-addr.arpa
33.in-addr.arpa
34.in-addr.arpa
35.in-addr.arpa
36.in-addr.arpa
37.in-addr.arpa
38.in-addr.arpa
39.in-addr.arpa
/5 is not on a 8-bit boundary, so it takes 8 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00100000.00000000.00000000.0000000032.0.0.0
Subnet mask11111000.00000000.00000000.00000000248.0.0.0
Network00100000.00000000.00000000.0000000032.0.0.0
Broadcast00100111.11111111.11111111.1111111139.255.255.255
Split into smaller subnets/14
/6 (2)/7 (4)/8 (8)/9 (16)/10 (32)/11 (64)/12 (128)/13 (256)/14 (512)/15 (1,024)/16 (2,048)/17 (4,096)

32.0.0.0/5 makes 512 subnets of /14; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
132.0.0.0/1432.0.0.1 to 32.3.255.25432.3.255.255262,142
232.4.0.0/1432.4.0.1 to 32.7.255.25432.7.255.255262,142
332.8.0.0/1432.8.0.1 to 32.11.255.25432.11.255.255262,142
432.12.0.0/1432.12.0.1 to 32.15.255.25432.15.255.255262,142
532.16.0.0/1432.16.0.1 to 32.19.255.25432.19.255.255262,142
632.20.0.0/1432.20.0.1 to 32.23.255.25432.23.255.255262,142
732.24.0.0/1432.24.0.1 to 32.27.255.25432.27.255.255262,142
832.28.0.0/1432.28.0.1 to 32.31.255.25432.31.255.255262,142
932.32.0.0/1432.32.0.1 to 32.35.255.25432.35.255.255262,142
1032.36.0.0/1432.36.0.1 to 32.39.255.25432.39.255.255262,142
1132.40.0.0/1432.40.0.1 to 32.43.255.25432.43.255.255262,142
1232.44.0.0/1432.44.0.1 to 32.47.255.25432.47.255.255262,142
1332.48.0.0/1432.48.0.1 to 32.51.255.25432.51.255.255262,142
1432.52.0.0/1432.52.0.1 to 32.55.255.25432.55.255.255262,142
1532.56.0.0/1432.56.0.1 to 32.59.255.25432.59.255.255262,142
1632.60.0.0/1432.60.0.1 to 32.63.255.25432.63.255.255262,142
1732.64.0.0/1432.64.0.1 to 32.67.255.25432.67.255.255262,142
1832.68.0.0/1432.68.0.1 to 32.71.255.25432.71.255.255262,142
1932.72.0.0/1432.72.0.1 to 32.75.255.25432.75.255.255262,142
2032.76.0.0/1432.76.0.1 to 32.79.255.25432.79.255.255262,142
2132.80.0.0/1432.80.0.1 to 32.83.255.25432.83.255.255262,142
2232.84.0.0/1432.84.0.1 to 32.87.255.25432.87.255.255262,142
2332.88.0.0/1432.88.0.1 to 32.91.255.25432.91.255.255262,142
2432.92.0.0/1432.92.0.1 to 32.95.255.25432.95.255.255262,142
2532.96.0.0/1432.96.0.1 to 32.99.255.25432.99.255.255262,142
2632.100.0.0/1432.100.0.1 to 32.103.255.25432.103.255.255262,142
2732.104.0.0/1432.104.0.1 to 32.107.255.25432.107.255.255262,142
2832.108.0.0/1432.108.0.1 to 32.111.255.25432.111.255.255262,142
2932.112.0.0/1432.112.0.1 to 32.115.255.25432.115.255.255262,142
3032.116.0.0/1432.116.0.1 to 32.119.255.25432.119.255.255262,142
3132.120.0.0/1432.120.0.1 to 32.123.255.25432.123.255.255262,142
3232.124.0.0/1432.124.0.1 to 32.127.255.25432.127.255.255262,142
3332.128.0.0/1432.128.0.1 to 32.131.255.25432.131.255.255262,142
3432.132.0.0/1432.132.0.1 to 32.135.255.25432.135.255.255262,142
3532.136.0.0/1432.136.0.1 to 32.139.255.25432.139.255.255262,142
3632.140.0.0/1432.140.0.1 to 32.143.255.25432.143.255.255262,142
3732.144.0.0/1432.144.0.1 to 32.147.255.25432.147.255.255262,142
3832.148.0.0/1432.148.0.1 to 32.151.255.25432.151.255.255262,142
3932.152.0.0/1432.152.0.1 to 32.155.255.25432.155.255.255262,142
4032.156.0.0/1432.156.0.1 to 32.159.255.25432.159.255.255262,142
4132.160.0.0/1432.160.0.1 to 32.163.255.25432.163.255.255262,142
4232.164.0.0/1432.164.0.1 to 32.167.255.25432.167.255.255262,142
4332.168.0.0/1432.168.0.1 to 32.171.255.25432.171.255.255262,142
4432.172.0.0/1432.172.0.1 to 32.175.255.25432.175.255.255262,142
4532.176.0.0/1432.176.0.1 to 32.179.255.25432.179.255.255262,142
4632.180.0.0/1432.180.0.1 to 32.183.255.25432.183.255.255262,142
4732.184.0.0/1432.184.0.1 to 32.187.255.25432.187.255.255262,142
4832.188.0.0/1432.188.0.1 to 32.191.255.25432.191.255.255262,142
4932.192.0.0/1432.192.0.1 to 32.195.255.25432.195.255.255262,142
5032.196.0.0/1432.196.0.1 to 32.199.255.25432.199.255.255262,142
5132.200.0.0/1432.200.0.1 to 32.203.255.25432.203.255.255262,142
5232.204.0.0/1432.204.0.1 to 32.207.255.25432.207.255.255262,142
5332.208.0.0/1432.208.0.1 to 32.211.255.25432.211.255.255262,142
5432.212.0.0/1432.212.0.1 to 32.215.255.25432.215.255.255262,142
5532.216.0.0/1432.216.0.1 to 32.219.255.25432.219.255.255262,142
5632.220.0.0/1432.220.0.1 to 32.223.255.25432.223.255.255262,142
5732.224.0.0/1432.224.0.1 to 32.227.255.25432.227.255.255262,142
5832.228.0.0/1432.228.0.1 to 32.231.255.25432.231.255.255262,142
5932.232.0.0/1432.232.0.1 to 32.235.255.25432.235.255.255262,142
6032.236.0.0/1432.236.0.1 to 32.239.255.25432.239.255.255262,142
6132.240.0.0/1432.240.0.1 to 32.243.255.25432.243.255.255262,142
6232.244.0.0/1432.244.0.1 to 32.247.255.25432.247.255.255262,142
6332.248.0.0/1432.248.0.1 to 32.251.255.25432.251.255.255262,142
6432.252.0.0/1432.252.0.1 to 32.255.255.25432.255.255.255262,142
6533.0.0.0/1433.0.0.1 to 33.3.255.25433.3.255.255262,142
6633.4.0.0/1433.4.0.1 to 33.7.255.25433.7.255.255262,142
6733.8.0.0/1433.8.0.1 to 33.11.255.25433.11.255.255262,142
6833.12.0.0/1433.12.0.1 to 33.15.255.25433.15.255.255262,142
6933.16.0.0/1433.16.0.1 to 33.19.255.25433.19.255.255262,142
7033.20.0.0/1433.20.0.1 to 33.23.255.25433.23.255.255262,142
7133.24.0.0/1433.24.0.1 to 33.27.255.25433.27.255.255262,142
7233.28.0.0/1433.28.0.1 to 33.31.255.25433.31.255.255262,142
7333.32.0.0/1433.32.0.1 to 33.35.255.25433.35.255.255262,142
7433.36.0.0/1433.36.0.1 to 33.39.255.25433.39.255.255262,142
7533.40.0.0/1433.40.0.1 to 33.43.255.25433.43.255.255262,142
7633.44.0.0/1433.44.0.1 to 33.47.255.25433.47.255.255262,142
7733.48.0.0/1433.48.0.1 to 33.51.255.25433.51.255.255262,142
7833.52.0.0/1433.52.0.1 to 33.55.255.25433.55.255.255262,142
7933.56.0.0/1433.56.0.1 to 33.59.255.25433.59.255.255262,142
8033.60.0.0/1433.60.0.1 to 33.63.255.25433.63.255.255262,142
8133.64.0.0/1433.64.0.1 to 33.67.255.25433.67.255.255262,142
8233.68.0.0/1433.68.0.1 to 33.71.255.25433.71.255.255262,142
8333.72.0.0/1433.72.0.1 to 33.75.255.25433.75.255.255262,142
8433.76.0.0/1433.76.0.1 to 33.79.255.25433.79.255.255262,142
8533.80.0.0/1433.80.0.1 to 33.83.255.25433.83.255.255262,142
8633.84.0.0/1433.84.0.1 to 33.87.255.25433.87.255.255262,142
8733.88.0.0/1433.88.0.1 to 33.91.255.25433.91.255.255262,142
8833.92.0.0/1433.92.0.1 to 33.95.255.25433.95.255.255262,142
8933.96.0.0/1433.96.0.1 to 33.99.255.25433.99.255.255262,142
9033.100.0.0/1433.100.0.1 to 33.103.255.25433.103.255.255262,142
9133.104.0.0/1433.104.0.1 to 33.107.255.25433.107.255.255262,142
9233.108.0.0/1433.108.0.1 to 33.111.255.25433.111.255.255262,142
9333.112.0.0/1433.112.0.1 to 33.115.255.25433.115.255.255262,142
9433.116.0.0/1433.116.0.1 to 33.119.255.25433.119.255.255262,142
9533.120.0.0/1433.120.0.1 to 33.123.255.25433.123.255.255262,142
9633.124.0.0/1433.124.0.1 to 33.127.255.25433.127.255.255262,142
9733.128.0.0/1433.128.0.1 to 33.131.255.25433.131.255.255262,142
9833.132.0.0/1433.132.0.1 to 33.135.255.25433.135.255.255262,142
9933.136.0.0/1433.136.0.1 to 33.139.255.25433.139.255.255262,142
10033.140.0.0/1433.140.0.1 to 33.143.255.25433.143.255.255262,142
10133.144.0.0/1433.144.0.1 to 33.147.255.25433.147.255.255262,142
10233.148.0.0/1433.148.0.1 to 33.151.255.25433.151.255.255262,142
10333.152.0.0/1433.152.0.1 to 33.155.255.25433.155.255.255262,142
10433.156.0.0/1433.156.0.1 to 33.159.255.25433.159.255.255262,142
10533.160.0.0/1433.160.0.1 to 33.163.255.25433.163.255.255262,142
10633.164.0.0/1433.164.0.1 to 33.167.255.25433.167.255.255262,142
10733.168.0.0/1433.168.0.1 to 33.171.255.25433.171.255.255262,142
10833.172.0.0/1433.172.0.1 to 33.175.255.25433.175.255.255262,142
10933.176.0.0/1433.176.0.1 to 33.179.255.25433.179.255.255262,142
11033.180.0.0/1433.180.0.1 to 33.183.255.25433.183.255.255262,142
11133.184.0.0/1433.184.0.1 to 33.187.255.25433.187.255.255262,142
11233.188.0.0/1433.188.0.1 to 33.191.255.25433.191.255.255262,142
11333.192.0.0/1433.192.0.1 to 33.195.255.25433.195.255.255262,142
11433.196.0.0/1433.196.0.1 to 33.199.255.25433.199.255.255262,142
11533.200.0.0/1433.200.0.1 to 33.203.255.25433.203.255.255262,142
11633.204.0.0/1433.204.0.1 to 33.207.255.25433.207.255.255262,142
11733.208.0.0/1433.208.0.1 to 33.211.255.25433.211.255.255262,142
11833.212.0.0/1433.212.0.1 to 33.215.255.25433.215.255.255262,142
11933.216.0.0/1433.216.0.1 to 33.219.255.25433.219.255.255262,142
12033.220.0.0/1433.220.0.1 to 33.223.255.25433.223.255.255262,142
12133.224.0.0/1433.224.0.1 to 33.227.255.25433.227.255.255262,142
12233.228.0.0/1433.228.0.1 to 33.231.255.25433.231.255.255262,142
12333.232.0.0/1433.232.0.1 to 33.235.255.25433.235.255.255262,142
12433.236.0.0/1433.236.0.1 to 33.239.255.25433.239.255.255262,142
12533.240.0.0/1433.240.0.1 to 33.243.255.25433.243.255.255262,142
12633.244.0.0/1433.244.0.1 to 33.247.255.25433.247.255.255262,142
12733.248.0.0/1433.248.0.1 to 33.251.255.25433.251.255.255262,142
12833.252.0.0/1433.252.0.1 to 33.255.255.25433.255.255.255262,142
12934.0.0.0/1434.0.0.1 to 34.3.255.25434.3.255.255262,142
13034.4.0.0/1434.4.0.1 to 34.7.255.25434.7.255.255262,142
13134.8.0.0/1434.8.0.1 to 34.11.255.25434.11.255.255262,142
13234.12.0.0/1434.12.0.1 to 34.15.255.25434.15.255.255262,142
13334.16.0.0/1434.16.0.1 to 34.19.255.25434.19.255.255262,142
13434.20.0.0/1434.20.0.1 to 34.23.255.25434.23.255.255262,142
13534.24.0.0/1434.24.0.1 to 34.27.255.25434.27.255.255262,142
13634.28.0.0/1434.28.0.1 to 34.31.255.25434.31.255.255262,142
13734.32.0.0/1434.32.0.1 to 34.35.255.25434.35.255.255262,142
13834.36.0.0/1434.36.0.1 to 34.39.255.25434.39.255.255262,142
13934.40.0.0/1434.40.0.1 to 34.43.255.25434.43.255.255262,142
14034.44.0.0/1434.44.0.1 to 34.47.255.25434.47.255.255262,142
14134.48.0.0/1434.48.0.1 to 34.51.255.25434.51.255.255262,142
14234.52.0.0/1434.52.0.1 to 34.55.255.25434.55.255.255262,142
14334.56.0.0/1434.56.0.1 to 34.59.255.25434.59.255.255262,142
14434.60.0.0/1434.60.0.1 to 34.63.255.25434.63.255.255262,142
14534.64.0.0/1434.64.0.1 to 34.67.255.25434.67.255.255262,142
14634.68.0.0/1434.68.0.1 to 34.71.255.25434.71.255.255262,142
14734.72.0.0/1434.72.0.1 to 34.75.255.25434.75.255.255262,142
14834.76.0.0/1434.76.0.1 to 34.79.255.25434.79.255.255262,142
14934.80.0.0/1434.80.0.1 to 34.83.255.25434.83.255.255262,142
15034.84.0.0/1434.84.0.1 to 34.87.255.25434.87.255.255262,142
15134.88.0.0/1434.88.0.1 to 34.91.255.25434.91.255.255262,142
15234.92.0.0/1434.92.0.1 to 34.95.255.25434.95.255.255262,142
15334.96.0.0/1434.96.0.1 to 34.99.255.25434.99.255.255262,142
15434.100.0.0/1434.100.0.1 to 34.103.255.25434.103.255.255262,142
15534.104.0.0/1434.104.0.1 to 34.107.255.25434.107.255.255262,142
15634.108.0.0/1434.108.0.1 to 34.111.255.25434.111.255.255262,142
15734.112.0.0/1434.112.0.1 to 34.115.255.25434.115.255.255262,142
15834.116.0.0/1434.116.0.1 to 34.119.255.25434.119.255.255262,142
15934.120.0.0/1434.120.0.1 to 34.123.255.25434.123.255.255262,142
16034.124.0.0/1434.124.0.1 to 34.127.255.25434.127.255.255262,142
16134.128.0.0/1434.128.0.1 to 34.131.255.25434.131.255.255262,142
16234.132.0.0/1434.132.0.1 to 34.135.255.25434.135.255.255262,142
16334.136.0.0/1434.136.0.1 to 34.139.255.25434.139.255.255262,142
16434.140.0.0/1434.140.0.1 to 34.143.255.25434.143.255.255262,142
16534.144.0.0/1434.144.0.1 to 34.147.255.25434.147.255.255262,142
16634.148.0.0/1434.148.0.1 to 34.151.255.25434.151.255.255262,142
16734.152.0.0/1434.152.0.1 to 34.155.255.25434.155.255.255262,142
16834.156.0.0/1434.156.0.1 to 34.159.255.25434.159.255.255262,142
16934.160.0.0/1434.160.0.1 to 34.163.255.25434.163.255.255262,142
17034.164.0.0/1434.164.0.1 to 34.167.255.25434.167.255.255262,142
17134.168.0.0/1434.168.0.1 to 34.171.255.25434.171.255.255262,142
17234.172.0.0/1434.172.0.1 to 34.175.255.25434.175.255.255262,142
17334.176.0.0/1434.176.0.1 to 34.179.255.25434.179.255.255262,142
17434.180.0.0/1434.180.0.1 to 34.183.255.25434.183.255.255262,142
17534.184.0.0/1434.184.0.1 to 34.187.255.25434.187.255.255262,142
17634.188.0.0/1434.188.0.1 to 34.191.255.25434.191.255.255262,142
17734.192.0.0/1434.192.0.1 to 34.195.255.25434.195.255.255262,142
17834.196.0.0/1434.196.0.1 to 34.199.255.25434.199.255.255262,142
17934.200.0.0/1434.200.0.1 to 34.203.255.25434.203.255.255262,142
18034.204.0.0/1434.204.0.1 to 34.207.255.25434.207.255.255262,142
18134.208.0.0/1434.208.0.1 to 34.211.255.25434.211.255.255262,142
18234.212.0.0/1434.212.0.1 to 34.215.255.25434.215.255.255262,142
18334.216.0.0/1434.216.0.1 to 34.219.255.25434.219.255.255262,142
18434.220.0.0/1434.220.0.1 to 34.223.255.25434.223.255.255262,142
18534.224.0.0/1434.224.0.1 to 34.227.255.25434.227.255.255262,142
18634.228.0.0/1434.228.0.1 to 34.231.255.25434.231.255.255262,142
18734.232.0.0/1434.232.0.1 to 34.235.255.25434.235.255.255262,142
18834.236.0.0/1434.236.0.1 to 34.239.255.25434.239.255.255262,142
18934.240.0.0/1434.240.0.1 to 34.243.255.25434.243.255.255262,142
19034.244.0.0/1434.244.0.1 to 34.247.255.25434.247.255.255262,142
19134.248.0.0/1434.248.0.1 to 34.251.255.25434.251.255.255262,142
19234.252.0.0/1434.252.0.1 to 34.255.255.25434.255.255.255262,142
19335.0.0.0/1435.0.0.1 to 35.3.255.25435.3.255.255262,142
19435.4.0.0/1435.4.0.1 to 35.7.255.25435.7.255.255262,142
19535.8.0.0/1435.8.0.1 to 35.11.255.25435.11.255.255262,142
19635.12.0.0/1435.12.0.1 to 35.15.255.25435.15.255.255262,142
19735.16.0.0/1435.16.0.1 to 35.19.255.25435.19.255.255262,142
19835.20.0.0/1435.20.0.1 to 35.23.255.25435.23.255.255262,142
19935.24.0.0/1435.24.0.1 to 35.27.255.25435.27.255.255262,142
20035.28.0.0/1435.28.0.1 to 35.31.255.25435.31.255.255262,142
20135.32.0.0/1435.32.0.1 to 35.35.255.25435.35.255.255262,142
20235.36.0.0/1435.36.0.1 to 35.39.255.25435.39.255.255262,142
20335.40.0.0/1435.40.0.1 to 35.43.255.25435.43.255.255262,142
20435.44.0.0/1435.44.0.1 to 35.47.255.25435.47.255.255262,142
20535.48.0.0/1435.48.0.1 to 35.51.255.25435.51.255.255262,142
20635.52.0.0/1435.52.0.1 to 35.55.255.25435.55.255.255262,142
20735.56.0.0/1435.56.0.1 to 35.59.255.25435.59.255.255262,142
20835.60.0.0/1435.60.0.1 to 35.63.255.25435.63.255.255262,142
20935.64.0.0/1435.64.0.1 to 35.67.255.25435.67.255.255262,142
21035.68.0.0/1435.68.0.1 to 35.71.255.25435.71.255.255262,142
21135.72.0.0/1435.72.0.1 to 35.75.255.25435.75.255.255262,142
21235.76.0.0/1435.76.0.1 to 35.79.255.25435.79.255.255262,142
21335.80.0.0/1435.80.0.1 to 35.83.255.25435.83.255.255262,142
21435.84.0.0/1435.84.0.1 to 35.87.255.25435.87.255.255262,142
21535.88.0.0/1435.88.0.1 to 35.91.255.25435.91.255.255262,142
21635.92.0.0/1435.92.0.1 to 35.95.255.25435.95.255.255262,142
21735.96.0.0/1435.96.0.1 to 35.99.255.25435.99.255.255262,142
21835.100.0.0/1435.100.0.1 to 35.103.255.25435.103.255.255262,142
21935.104.0.0/1435.104.0.1 to 35.107.255.25435.107.255.255262,142
22035.108.0.0/1435.108.0.1 to 35.111.255.25435.111.255.255262,142
22135.112.0.0/1435.112.0.1 to 35.115.255.25435.115.255.255262,142
22235.116.0.0/1435.116.0.1 to 35.119.255.25435.119.255.255262,142
22335.120.0.0/1435.120.0.1 to 35.123.255.25435.123.255.255262,142
22435.124.0.0/1435.124.0.1 to 35.127.255.25435.127.255.255262,142
22535.128.0.0/1435.128.0.1 to 35.131.255.25435.131.255.255262,142
22635.132.0.0/1435.132.0.1 to 35.135.255.25435.135.255.255262,142
22735.136.0.0/1435.136.0.1 to 35.139.255.25435.139.255.255262,142
22835.140.0.0/1435.140.0.1 to 35.143.255.25435.143.255.255262,142
22935.144.0.0/1435.144.0.1 to 35.147.255.25435.147.255.255262,142
23035.148.0.0/1435.148.0.1 to 35.151.255.25435.151.255.255262,142
23135.152.0.0/1435.152.0.1 to 35.155.255.25435.155.255.255262,142
23235.156.0.0/1435.156.0.1 to 35.159.255.25435.159.255.255262,142
23335.160.0.0/1435.160.0.1 to 35.163.255.25435.163.255.255262,142
23435.164.0.0/1435.164.0.1 to 35.167.255.25435.167.255.255262,142
23535.168.0.0/1435.168.0.1 to 35.171.255.25435.171.255.255262,142
23635.172.0.0/1435.172.0.1 to 35.175.255.25435.175.255.255262,142
23735.176.0.0/1435.176.0.1 to 35.179.255.25435.179.255.255262,142
23835.180.0.0/1435.180.0.1 to 35.183.255.25435.183.255.255262,142
23935.184.0.0/1435.184.0.1 to 35.187.255.25435.187.255.255262,142
24035.188.0.0/1435.188.0.1 to 35.191.255.25435.191.255.255262,142
24135.192.0.0/1435.192.0.1 to 35.195.255.25435.195.255.255262,142
24235.196.0.0/1435.196.0.1 to 35.199.255.25435.199.255.255262,142
24335.200.0.0/1435.200.0.1 to 35.203.255.25435.203.255.255262,142
24435.204.0.0/1435.204.0.1 to 35.207.255.25435.207.255.255262,142
24535.208.0.0/1435.208.0.1 to 35.211.255.25435.211.255.255262,142
24635.212.0.0/1435.212.0.1 to 35.215.255.25435.215.255.255262,142
24735.216.0.0/1435.216.0.1 to 35.219.255.25435.219.255.255262,142
24835.220.0.0/1435.220.0.1 to 35.223.255.25435.223.255.255262,142
24935.224.0.0/1435.224.0.1 to 35.227.255.25435.227.255.255262,142
25035.228.0.0/1435.228.0.1 to 35.231.255.25435.231.255.255262,142
25135.232.0.0/1435.232.0.1 to 35.235.255.25435.235.255.255262,142
25235.236.0.0/1435.236.0.1 to 35.239.255.25435.239.255.255262,142
25335.240.0.0/1435.240.0.1 to 35.243.255.25435.243.255.255262,142
25435.244.0.0/1435.244.0.1 to 35.247.255.25435.247.255.255262,142
25535.248.0.0/1435.248.0.1 to 35.251.255.25435.251.255.255262,142
25635.252.0.0/1435.252.0.1 to 35.255.255.25435.255.255.255262,142

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.