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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.

Network50.32.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
50.32.0.0
Broadcast address
50.63.255.255
First usable
50.32.0.1
Last usable
50.63.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Public public
Old class
A (default /8)
As numbers
Hex 32200000 · Integer 840957952 to 843055103
Reverse DNS zones
32.50.in-addr.arpa
33.50.in-addr.arpa
34.50.in-addr.arpa
35.50.in-addr.arpa
36.50.in-addr.arpa
37.50.in-addr.arpa
38.50.in-addr.arpa
39.50.in-addr.arpa
40.50.in-addr.arpa
41.50.in-addr.arpa
42.50.in-addr.arpa
43.50.in-addr.arpa
44.50.in-addr.arpa
45.50.in-addr.arpa
46.50.in-addr.arpa
47.50.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110010.00100000.00000000.0000000050.32.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network00110010.00100000.00000000.0000000050.32.0.0
Broadcast00110010.00111111.11111111.1111111150.63.255.255
Split into smaller subnets/21
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

50.32.0.0/11 makes 1,024 subnets of /21; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
150.32.0.0/2150.32.0.1 to 50.32.7.25450.32.7.2552,046
250.32.8.0/2150.32.8.1 to 50.32.15.25450.32.15.2552,046
350.32.16.0/2150.32.16.1 to 50.32.23.25450.32.23.2552,046
450.32.24.0/2150.32.24.1 to 50.32.31.25450.32.31.2552,046
550.32.32.0/2150.32.32.1 to 50.32.39.25450.32.39.2552,046
650.32.40.0/2150.32.40.1 to 50.32.47.25450.32.47.2552,046
750.32.48.0/2150.32.48.1 to 50.32.55.25450.32.55.2552,046
850.32.56.0/2150.32.56.1 to 50.32.63.25450.32.63.2552,046
950.32.64.0/2150.32.64.1 to 50.32.71.25450.32.71.2552,046
1050.32.72.0/2150.32.72.1 to 50.32.79.25450.32.79.2552,046
1150.32.80.0/2150.32.80.1 to 50.32.87.25450.32.87.2552,046
1250.32.88.0/2150.32.88.1 to 50.32.95.25450.32.95.2552,046
1350.32.96.0/2150.32.96.1 to 50.32.103.25450.32.103.2552,046
1450.32.104.0/2150.32.104.1 to 50.32.111.25450.32.111.2552,046
1550.32.112.0/2150.32.112.1 to 50.32.119.25450.32.119.2552,046
1650.32.120.0/2150.32.120.1 to 50.32.127.25450.32.127.2552,046
1750.32.128.0/2150.32.128.1 to 50.32.135.25450.32.135.2552,046
1850.32.136.0/2150.32.136.1 to 50.32.143.25450.32.143.2552,046
1950.32.144.0/2150.32.144.1 to 50.32.151.25450.32.151.2552,046
2050.32.152.0/2150.32.152.1 to 50.32.159.25450.32.159.2552,046
2150.32.160.0/2150.32.160.1 to 50.32.167.25450.32.167.2552,046
2250.32.168.0/2150.32.168.1 to 50.32.175.25450.32.175.2552,046
2350.32.176.0/2150.32.176.1 to 50.32.183.25450.32.183.2552,046
2450.32.184.0/2150.32.184.1 to 50.32.191.25450.32.191.2552,046
2550.32.192.0/2150.32.192.1 to 50.32.199.25450.32.199.2552,046
2650.32.200.0/2150.32.200.1 to 50.32.207.25450.32.207.2552,046
2750.32.208.0/2150.32.208.1 to 50.32.215.25450.32.215.2552,046
2850.32.216.0/2150.32.216.1 to 50.32.223.25450.32.223.2552,046
2950.32.224.0/2150.32.224.1 to 50.32.231.25450.32.231.2552,046
3050.32.232.0/2150.32.232.1 to 50.32.239.25450.32.239.2552,046
3150.32.240.0/2150.32.240.1 to 50.32.247.25450.32.247.2552,046
3250.32.248.0/2150.32.248.1 to 50.32.255.25450.32.255.2552,046
3350.33.0.0/2150.33.0.1 to 50.33.7.25450.33.7.2552,046
3450.33.8.0/2150.33.8.1 to 50.33.15.25450.33.15.2552,046
3550.33.16.0/2150.33.16.1 to 50.33.23.25450.33.23.2552,046
3650.33.24.0/2150.33.24.1 to 50.33.31.25450.33.31.2552,046
3750.33.32.0/2150.33.32.1 to 50.33.39.25450.33.39.2552,046
3850.33.40.0/2150.33.40.1 to 50.33.47.25450.33.47.2552,046
3950.33.48.0/2150.33.48.1 to 50.33.55.25450.33.55.2552,046
4050.33.56.0/2150.33.56.1 to 50.33.63.25450.33.63.2552,046
4150.33.64.0/2150.33.64.1 to 50.33.71.25450.33.71.2552,046
4250.33.72.0/2150.33.72.1 to 50.33.79.25450.33.79.2552,046
4350.33.80.0/2150.33.80.1 to 50.33.87.25450.33.87.2552,046
4450.33.88.0/2150.33.88.1 to 50.33.95.25450.33.95.2552,046
4550.33.96.0/2150.33.96.1 to 50.33.103.25450.33.103.2552,046
4650.33.104.0/2150.33.104.1 to 50.33.111.25450.33.111.2552,046
4750.33.112.0/2150.33.112.1 to 50.33.119.25450.33.119.2552,046
4850.33.120.0/2150.33.120.1 to 50.33.127.25450.33.127.2552,046
4950.33.128.0/2150.33.128.1 to 50.33.135.25450.33.135.2552,046
5050.33.136.0/2150.33.136.1 to 50.33.143.25450.33.143.2552,046
5150.33.144.0/2150.33.144.1 to 50.33.151.25450.33.151.2552,046
5250.33.152.0/2150.33.152.1 to 50.33.159.25450.33.159.2552,046
5350.33.160.0/2150.33.160.1 to 50.33.167.25450.33.167.2552,046
5450.33.168.0/2150.33.168.1 to 50.33.175.25450.33.175.2552,046
5550.33.176.0/2150.33.176.1 to 50.33.183.25450.33.183.2552,046
5650.33.184.0/2150.33.184.1 to 50.33.191.25450.33.191.2552,046
5750.33.192.0/2150.33.192.1 to 50.33.199.25450.33.199.2552,046
5850.33.200.0/2150.33.200.1 to 50.33.207.25450.33.207.2552,046
5950.33.208.0/2150.33.208.1 to 50.33.215.25450.33.215.2552,046
6050.33.216.0/2150.33.216.1 to 50.33.223.25450.33.223.2552,046
6150.33.224.0/2150.33.224.1 to 50.33.231.25450.33.231.2552,046
6250.33.232.0/2150.33.232.1 to 50.33.239.25450.33.239.2552,046
6350.33.240.0/2150.33.240.1 to 50.33.247.25450.33.247.2552,046
6450.33.248.0/2150.33.248.1 to 50.33.255.25450.33.255.2552,046
6550.34.0.0/2150.34.0.1 to 50.34.7.25450.34.7.2552,046
6650.34.8.0/2150.34.8.1 to 50.34.15.25450.34.15.2552,046
6750.34.16.0/2150.34.16.1 to 50.34.23.25450.34.23.2552,046
6850.34.24.0/2150.34.24.1 to 50.34.31.25450.34.31.2552,046
6950.34.32.0/2150.34.32.1 to 50.34.39.25450.34.39.2552,046
7050.34.40.0/2150.34.40.1 to 50.34.47.25450.34.47.2552,046
7150.34.48.0/2150.34.48.1 to 50.34.55.25450.34.55.2552,046
7250.34.56.0/2150.34.56.1 to 50.34.63.25450.34.63.2552,046
7350.34.64.0/2150.34.64.1 to 50.34.71.25450.34.71.2552,046
7450.34.72.0/2150.34.72.1 to 50.34.79.25450.34.79.2552,046
7550.34.80.0/2150.34.80.1 to 50.34.87.25450.34.87.2552,046
7650.34.88.0/2150.34.88.1 to 50.34.95.25450.34.95.2552,046
7750.34.96.0/2150.34.96.1 to 50.34.103.25450.34.103.2552,046
7850.34.104.0/2150.34.104.1 to 50.34.111.25450.34.111.2552,046
7950.34.112.0/2150.34.112.1 to 50.34.119.25450.34.119.2552,046
8050.34.120.0/2150.34.120.1 to 50.34.127.25450.34.127.2552,046
8150.34.128.0/2150.34.128.1 to 50.34.135.25450.34.135.2552,046
8250.34.136.0/2150.34.136.1 to 50.34.143.25450.34.143.2552,046
8350.34.144.0/2150.34.144.1 to 50.34.151.25450.34.151.2552,046
8450.34.152.0/2150.34.152.1 to 50.34.159.25450.34.159.2552,046
8550.34.160.0/2150.34.160.1 to 50.34.167.25450.34.167.2552,046
8650.34.168.0/2150.34.168.1 to 50.34.175.25450.34.175.2552,046
8750.34.176.0/2150.34.176.1 to 50.34.183.25450.34.183.2552,046
8850.34.184.0/2150.34.184.1 to 50.34.191.25450.34.191.2552,046
8950.34.192.0/2150.34.192.1 to 50.34.199.25450.34.199.2552,046
9050.34.200.0/2150.34.200.1 to 50.34.207.25450.34.207.2552,046
9150.34.208.0/2150.34.208.1 to 50.34.215.25450.34.215.2552,046
9250.34.216.0/2150.34.216.1 to 50.34.223.25450.34.223.2552,046
9350.34.224.0/2150.34.224.1 to 50.34.231.25450.34.231.2552,046
9450.34.232.0/2150.34.232.1 to 50.34.239.25450.34.239.2552,046
9550.34.240.0/2150.34.240.1 to 50.34.247.25450.34.247.2552,046
9650.34.248.0/2150.34.248.1 to 50.34.255.25450.34.255.2552,046
9750.35.0.0/2150.35.0.1 to 50.35.7.25450.35.7.2552,046
9850.35.8.0/2150.35.8.1 to 50.35.15.25450.35.15.2552,046
9950.35.16.0/2150.35.16.1 to 50.35.23.25450.35.23.2552,046
10050.35.24.0/2150.35.24.1 to 50.35.31.25450.35.31.2552,046
10150.35.32.0/2150.35.32.1 to 50.35.39.25450.35.39.2552,046
10250.35.40.0/2150.35.40.1 to 50.35.47.25450.35.47.2552,046
10350.35.48.0/2150.35.48.1 to 50.35.55.25450.35.55.2552,046
10450.35.56.0/2150.35.56.1 to 50.35.63.25450.35.63.2552,046
10550.35.64.0/2150.35.64.1 to 50.35.71.25450.35.71.2552,046
10650.35.72.0/2150.35.72.1 to 50.35.79.25450.35.79.2552,046
10750.35.80.0/2150.35.80.1 to 50.35.87.25450.35.87.2552,046
10850.35.88.0/2150.35.88.1 to 50.35.95.25450.35.95.2552,046
10950.35.96.0/2150.35.96.1 to 50.35.103.25450.35.103.2552,046
11050.35.104.0/2150.35.104.1 to 50.35.111.25450.35.111.2552,046
11150.35.112.0/2150.35.112.1 to 50.35.119.25450.35.119.2552,046
11250.35.120.0/2150.35.120.1 to 50.35.127.25450.35.127.2552,046
11350.35.128.0/2150.35.128.1 to 50.35.135.25450.35.135.2552,046
11450.35.136.0/2150.35.136.1 to 50.35.143.25450.35.143.2552,046
11550.35.144.0/2150.35.144.1 to 50.35.151.25450.35.151.2552,046
11650.35.152.0/2150.35.152.1 to 50.35.159.25450.35.159.2552,046
11750.35.160.0/2150.35.160.1 to 50.35.167.25450.35.167.2552,046
11850.35.168.0/2150.35.168.1 to 50.35.175.25450.35.175.2552,046
11950.35.176.0/2150.35.176.1 to 50.35.183.25450.35.183.2552,046
12050.35.184.0/2150.35.184.1 to 50.35.191.25450.35.191.2552,046
12150.35.192.0/2150.35.192.1 to 50.35.199.25450.35.199.2552,046
12250.35.200.0/2150.35.200.1 to 50.35.207.25450.35.207.2552,046
12350.35.208.0/2150.35.208.1 to 50.35.215.25450.35.215.2552,046
12450.35.216.0/2150.35.216.1 to 50.35.223.25450.35.223.2552,046
12550.35.224.0/2150.35.224.1 to 50.35.231.25450.35.231.2552,046
12650.35.232.0/2150.35.232.1 to 50.35.239.25450.35.239.2552,046
12750.35.240.0/2150.35.240.1 to 50.35.247.25450.35.247.2552,046
12850.35.248.0/2150.35.248.1 to 50.35.255.25450.35.255.2552,046
12950.36.0.0/2150.36.0.1 to 50.36.7.25450.36.7.2552,046
13050.36.8.0/2150.36.8.1 to 50.36.15.25450.36.15.2552,046
13150.36.16.0/2150.36.16.1 to 50.36.23.25450.36.23.2552,046
13250.36.24.0/2150.36.24.1 to 50.36.31.25450.36.31.2552,046
13350.36.32.0/2150.36.32.1 to 50.36.39.25450.36.39.2552,046
13450.36.40.0/2150.36.40.1 to 50.36.47.25450.36.47.2552,046
13550.36.48.0/2150.36.48.1 to 50.36.55.25450.36.55.2552,046
13650.36.56.0/2150.36.56.1 to 50.36.63.25450.36.63.2552,046
13750.36.64.0/2150.36.64.1 to 50.36.71.25450.36.71.2552,046
13850.36.72.0/2150.36.72.1 to 50.36.79.25450.36.79.2552,046
13950.36.80.0/2150.36.80.1 to 50.36.87.25450.36.87.2552,046
14050.36.88.0/2150.36.88.1 to 50.36.95.25450.36.95.2552,046
14150.36.96.0/2150.36.96.1 to 50.36.103.25450.36.103.2552,046
14250.36.104.0/2150.36.104.1 to 50.36.111.25450.36.111.2552,046
14350.36.112.0/2150.36.112.1 to 50.36.119.25450.36.119.2552,046
14450.36.120.0/2150.36.120.1 to 50.36.127.25450.36.127.2552,046
14550.36.128.0/2150.36.128.1 to 50.36.135.25450.36.135.2552,046
14650.36.136.0/2150.36.136.1 to 50.36.143.25450.36.143.2552,046
14750.36.144.0/2150.36.144.1 to 50.36.151.25450.36.151.2552,046
14850.36.152.0/2150.36.152.1 to 50.36.159.25450.36.159.2552,046
14950.36.160.0/2150.36.160.1 to 50.36.167.25450.36.167.2552,046
15050.36.168.0/2150.36.168.1 to 50.36.175.25450.36.175.2552,046
15150.36.176.0/2150.36.176.1 to 50.36.183.25450.36.183.2552,046
15250.36.184.0/2150.36.184.1 to 50.36.191.25450.36.191.2552,046
15350.36.192.0/2150.36.192.1 to 50.36.199.25450.36.199.2552,046
15450.36.200.0/2150.36.200.1 to 50.36.207.25450.36.207.2552,046
15550.36.208.0/2150.36.208.1 to 50.36.215.25450.36.215.2552,046
15650.36.216.0/2150.36.216.1 to 50.36.223.25450.36.223.2552,046
15750.36.224.0/2150.36.224.1 to 50.36.231.25450.36.231.2552,046
15850.36.232.0/2150.36.232.1 to 50.36.239.25450.36.239.2552,046
15950.36.240.0/2150.36.240.1 to 50.36.247.25450.36.247.2552,046
16050.36.248.0/2150.36.248.1 to 50.36.255.25450.36.255.2552,046
16150.37.0.0/2150.37.0.1 to 50.37.7.25450.37.7.2552,046
16250.37.8.0/2150.37.8.1 to 50.37.15.25450.37.15.2552,046
16350.37.16.0/2150.37.16.1 to 50.37.23.25450.37.23.2552,046
16450.37.24.0/2150.37.24.1 to 50.37.31.25450.37.31.2552,046
16550.37.32.0/2150.37.32.1 to 50.37.39.25450.37.39.2552,046
16650.37.40.0/2150.37.40.1 to 50.37.47.25450.37.47.2552,046
16750.37.48.0/2150.37.48.1 to 50.37.55.25450.37.55.2552,046
16850.37.56.0/2150.37.56.1 to 50.37.63.25450.37.63.2552,046
16950.37.64.0/2150.37.64.1 to 50.37.71.25450.37.71.2552,046
17050.37.72.0/2150.37.72.1 to 50.37.79.25450.37.79.2552,046
17150.37.80.0/2150.37.80.1 to 50.37.87.25450.37.87.2552,046
17250.37.88.0/2150.37.88.1 to 50.37.95.25450.37.95.2552,046
17350.37.96.0/2150.37.96.1 to 50.37.103.25450.37.103.2552,046
17450.37.104.0/2150.37.104.1 to 50.37.111.25450.37.111.2552,046
17550.37.112.0/2150.37.112.1 to 50.37.119.25450.37.119.2552,046
17650.37.120.0/2150.37.120.1 to 50.37.127.25450.37.127.2552,046
17750.37.128.0/2150.37.128.1 to 50.37.135.25450.37.135.2552,046
17850.37.136.0/2150.37.136.1 to 50.37.143.25450.37.143.2552,046
17950.37.144.0/2150.37.144.1 to 50.37.151.25450.37.151.2552,046
18050.37.152.0/2150.37.152.1 to 50.37.159.25450.37.159.2552,046
18150.37.160.0/2150.37.160.1 to 50.37.167.25450.37.167.2552,046
18250.37.168.0/2150.37.168.1 to 50.37.175.25450.37.175.2552,046
18350.37.176.0/2150.37.176.1 to 50.37.183.25450.37.183.2552,046
18450.37.184.0/2150.37.184.1 to 50.37.191.25450.37.191.2552,046
18550.37.192.0/2150.37.192.1 to 50.37.199.25450.37.199.2552,046
18650.37.200.0/2150.37.200.1 to 50.37.207.25450.37.207.2552,046
18750.37.208.0/2150.37.208.1 to 50.37.215.25450.37.215.2552,046
18850.37.216.0/2150.37.216.1 to 50.37.223.25450.37.223.2552,046
18950.37.224.0/2150.37.224.1 to 50.37.231.25450.37.231.2552,046
19050.37.232.0/2150.37.232.1 to 50.37.239.25450.37.239.2552,046
19150.37.240.0/2150.37.240.1 to 50.37.247.25450.37.247.2552,046
19250.37.248.0/2150.37.248.1 to 50.37.255.25450.37.255.2552,046
19350.38.0.0/2150.38.0.1 to 50.38.7.25450.38.7.2552,046
19450.38.8.0/2150.38.8.1 to 50.38.15.25450.38.15.2552,046
19550.38.16.0/2150.38.16.1 to 50.38.23.25450.38.23.2552,046
19650.38.24.0/2150.38.24.1 to 50.38.31.25450.38.31.2552,046
19750.38.32.0/2150.38.32.1 to 50.38.39.25450.38.39.2552,046
19850.38.40.0/2150.38.40.1 to 50.38.47.25450.38.47.2552,046
19950.38.48.0/2150.38.48.1 to 50.38.55.25450.38.55.2552,046
20050.38.56.0/2150.38.56.1 to 50.38.63.25450.38.63.2552,046
20150.38.64.0/2150.38.64.1 to 50.38.71.25450.38.71.2552,046
20250.38.72.0/2150.38.72.1 to 50.38.79.25450.38.79.2552,046
20350.38.80.0/2150.38.80.1 to 50.38.87.25450.38.87.2552,046
20450.38.88.0/2150.38.88.1 to 50.38.95.25450.38.95.2552,046
20550.38.96.0/2150.38.96.1 to 50.38.103.25450.38.103.2552,046
20650.38.104.0/2150.38.104.1 to 50.38.111.25450.38.111.2552,046
20750.38.112.0/2150.38.112.1 to 50.38.119.25450.38.119.2552,046
20850.38.120.0/2150.38.120.1 to 50.38.127.25450.38.127.2552,046
20950.38.128.0/2150.38.128.1 to 50.38.135.25450.38.135.2552,046
21050.38.136.0/2150.38.136.1 to 50.38.143.25450.38.143.2552,046
21150.38.144.0/2150.38.144.1 to 50.38.151.25450.38.151.2552,046
21250.38.152.0/2150.38.152.1 to 50.38.159.25450.38.159.2552,046
21350.38.160.0/2150.38.160.1 to 50.38.167.25450.38.167.2552,046
21450.38.168.0/2150.38.168.1 to 50.38.175.25450.38.175.2552,046
21550.38.176.0/2150.38.176.1 to 50.38.183.25450.38.183.2552,046
21650.38.184.0/2150.38.184.1 to 50.38.191.25450.38.191.2552,046
21750.38.192.0/2150.38.192.1 to 50.38.199.25450.38.199.2552,046
21850.38.200.0/2150.38.200.1 to 50.38.207.25450.38.207.2552,046
21950.38.208.0/2150.38.208.1 to 50.38.215.25450.38.215.2552,046
22050.38.216.0/2150.38.216.1 to 50.38.223.25450.38.223.2552,046
22150.38.224.0/2150.38.224.1 to 50.38.231.25450.38.231.2552,046
22250.38.232.0/2150.38.232.1 to 50.38.239.25450.38.239.2552,046
22350.38.240.0/2150.38.240.1 to 50.38.247.25450.38.247.2552,046
22450.38.248.0/2150.38.248.1 to 50.38.255.25450.38.255.2552,046
22550.39.0.0/2150.39.0.1 to 50.39.7.25450.39.7.2552,046
22650.39.8.0/2150.39.8.1 to 50.39.15.25450.39.15.2552,046
22750.39.16.0/2150.39.16.1 to 50.39.23.25450.39.23.2552,046
22850.39.24.0/2150.39.24.1 to 50.39.31.25450.39.31.2552,046
22950.39.32.0/2150.39.32.1 to 50.39.39.25450.39.39.2552,046
23050.39.40.0/2150.39.40.1 to 50.39.47.25450.39.47.2552,046
23150.39.48.0/2150.39.48.1 to 50.39.55.25450.39.55.2552,046
23250.39.56.0/2150.39.56.1 to 50.39.63.25450.39.63.2552,046
23350.39.64.0/2150.39.64.1 to 50.39.71.25450.39.71.2552,046
23450.39.72.0/2150.39.72.1 to 50.39.79.25450.39.79.2552,046
23550.39.80.0/2150.39.80.1 to 50.39.87.25450.39.87.2552,046
23650.39.88.0/2150.39.88.1 to 50.39.95.25450.39.95.2552,046
23750.39.96.0/2150.39.96.1 to 50.39.103.25450.39.103.2552,046
23850.39.104.0/2150.39.104.1 to 50.39.111.25450.39.111.2552,046
23950.39.112.0/2150.39.112.1 to 50.39.119.25450.39.119.2552,046
24050.39.120.0/2150.39.120.1 to 50.39.127.25450.39.127.2552,046
24150.39.128.0/2150.39.128.1 to 50.39.135.25450.39.135.2552,046
24250.39.136.0/2150.39.136.1 to 50.39.143.25450.39.143.2552,046
24350.39.144.0/2150.39.144.1 to 50.39.151.25450.39.151.2552,046
24450.39.152.0/2150.39.152.1 to 50.39.159.25450.39.159.2552,046
24550.39.160.0/2150.39.160.1 to 50.39.167.25450.39.167.2552,046
24650.39.168.0/2150.39.168.1 to 50.39.175.25450.39.175.2552,046
24750.39.176.0/2150.39.176.1 to 50.39.183.25450.39.183.2552,046
24850.39.184.0/2150.39.184.1 to 50.39.191.25450.39.191.2552,046
24950.39.192.0/2150.39.192.1 to 50.39.199.25450.39.199.2552,046
25050.39.200.0/2150.39.200.1 to 50.39.207.25450.39.207.2552,046
25150.39.208.0/2150.39.208.1 to 50.39.215.25450.39.215.2552,046
25250.39.216.0/2150.39.216.1 to 50.39.223.25450.39.223.2552,046
25350.39.224.0/2150.39.224.1 to 50.39.231.25450.39.231.2552,046
25450.39.232.0/2150.39.232.1 to 50.39.239.25450.39.239.2552,046
25550.39.240.0/2150.39.240.1 to 50.39.247.25450.39.247.2552,046
25650.39.248.0/2150.39.248.1 to 50.39.255.25450.39.255.2552,046

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.