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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.

Network62.64.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
62.64.0.0
Broadcast address
62.127.255.255
First usable
62.64.0.1
Last usable
62.127.255.254
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 3E400000 · Integer 1044381696 to 1048575999
Reverse DNS zones
64.62.in-addr.arpa
65.62.in-addr.arpa
66.62.in-addr.arpa
67.62.in-addr.arpa
68.62.in-addr.arpa
69.62.in-addr.arpa
70.62.in-addr.arpa
71.62.in-addr.arpa
72.62.in-addr.arpa
73.62.in-addr.arpa
74.62.in-addr.arpa
75.62.in-addr.arpa
76.62.in-addr.arpa
77.62.in-addr.arpa
78.62.in-addr.arpa
79.62.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
Address00111110.01000000.00000000.0000000062.64.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00111110.01000000.00000000.0000000062.64.0.0
Broadcast00111110.01111111.11111111.1111111162.127.255.255
Split into smaller subnets/20
/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)

62.64.0.0/10 makes 1,024 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
162.64.0.0/2062.64.0.1 to 62.64.15.25462.64.15.2554,094
262.64.16.0/2062.64.16.1 to 62.64.31.25462.64.31.2554,094
362.64.32.0/2062.64.32.1 to 62.64.47.25462.64.47.2554,094
462.64.48.0/2062.64.48.1 to 62.64.63.25462.64.63.2554,094
562.64.64.0/2062.64.64.1 to 62.64.79.25462.64.79.2554,094
662.64.80.0/2062.64.80.1 to 62.64.95.25462.64.95.2554,094
762.64.96.0/2062.64.96.1 to 62.64.111.25462.64.111.2554,094
862.64.112.0/2062.64.112.1 to 62.64.127.25462.64.127.2554,094
962.64.128.0/2062.64.128.1 to 62.64.143.25462.64.143.2554,094
1062.64.144.0/2062.64.144.1 to 62.64.159.25462.64.159.2554,094
1162.64.160.0/2062.64.160.1 to 62.64.175.25462.64.175.2554,094
1262.64.176.0/2062.64.176.1 to 62.64.191.25462.64.191.2554,094
1362.64.192.0/2062.64.192.1 to 62.64.207.25462.64.207.2554,094
1462.64.208.0/2062.64.208.1 to 62.64.223.25462.64.223.2554,094
1562.64.224.0/2062.64.224.1 to 62.64.239.25462.64.239.2554,094
1662.64.240.0/2062.64.240.1 to 62.64.255.25462.64.255.2554,094
1762.65.0.0/2062.65.0.1 to 62.65.15.25462.65.15.2554,094
1862.65.16.0/2062.65.16.1 to 62.65.31.25462.65.31.2554,094
1962.65.32.0/2062.65.32.1 to 62.65.47.25462.65.47.2554,094
2062.65.48.0/2062.65.48.1 to 62.65.63.25462.65.63.2554,094
2162.65.64.0/2062.65.64.1 to 62.65.79.25462.65.79.2554,094
2262.65.80.0/2062.65.80.1 to 62.65.95.25462.65.95.2554,094
2362.65.96.0/2062.65.96.1 to 62.65.111.25462.65.111.2554,094
2462.65.112.0/2062.65.112.1 to 62.65.127.25462.65.127.2554,094
2562.65.128.0/2062.65.128.1 to 62.65.143.25462.65.143.2554,094
2662.65.144.0/2062.65.144.1 to 62.65.159.25462.65.159.2554,094
2762.65.160.0/2062.65.160.1 to 62.65.175.25462.65.175.2554,094
2862.65.176.0/2062.65.176.1 to 62.65.191.25462.65.191.2554,094
2962.65.192.0/2062.65.192.1 to 62.65.207.25462.65.207.2554,094
3062.65.208.0/2062.65.208.1 to 62.65.223.25462.65.223.2554,094
3162.65.224.0/2062.65.224.1 to 62.65.239.25462.65.239.2554,094
3262.65.240.0/2062.65.240.1 to 62.65.255.25462.65.255.2554,094
3362.66.0.0/2062.66.0.1 to 62.66.15.25462.66.15.2554,094
3462.66.16.0/2062.66.16.1 to 62.66.31.25462.66.31.2554,094
3562.66.32.0/2062.66.32.1 to 62.66.47.25462.66.47.2554,094
3662.66.48.0/2062.66.48.1 to 62.66.63.25462.66.63.2554,094
3762.66.64.0/2062.66.64.1 to 62.66.79.25462.66.79.2554,094
3862.66.80.0/2062.66.80.1 to 62.66.95.25462.66.95.2554,094
3962.66.96.0/2062.66.96.1 to 62.66.111.25462.66.111.2554,094
4062.66.112.0/2062.66.112.1 to 62.66.127.25462.66.127.2554,094
4162.66.128.0/2062.66.128.1 to 62.66.143.25462.66.143.2554,094
4262.66.144.0/2062.66.144.1 to 62.66.159.25462.66.159.2554,094
4362.66.160.0/2062.66.160.1 to 62.66.175.25462.66.175.2554,094
4462.66.176.0/2062.66.176.1 to 62.66.191.25462.66.191.2554,094
4562.66.192.0/2062.66.192.1 to 62.66.207.25462.66.207.2554,094
4662.66.208.0/2062.66.208.1 to 62.66.223.25462.66.223.2554,094
4762.66.224.0/2062.66.224.1 to 62.66.239.25462.66.239.2554,094
4862.66.240.0/2062.66.240.1 to 62.66.255.25462.66.255.2554,094
4962.67.0.0/2062.67.0.1 to 62.67.15.25462.67.15.2554,094
5062.67.16.0/2062.67.16.1 to 62.67.31.25462.67.31.2554,094
5162.67.32.0/2062.67.32.1 to 62.67.47.25462.67.47.2554,094
5262.67.48.0/2062.67.48.1 to 62.67.63.25462.67.63.2554,094
5362.67.64.0/2062.67.64.1 to 62.67.79.25462.67.79.2554,094
5462.67.80.0/2062.67.80.1 to 62.67.95.25462.67.95.2554,094
5562.67.96.0/2062.67.96.1 to 62.67.111.25462.67.111.2554,094
5662.67.112.0/2062.67.112.1 to 62.67.127.25462.67.127.2554,094
5762.67.128.0/2062.67.128.1 to 62.67.143.25462.67.143.2554,094
5862.67.144.0/2062.67.144.1 to 62.67.159.25462.67.159.2554,094
5962.67.160.0/2062.67.160.1 to 62.67.175.25462.67.175.2554,094
6062.67.176.0/2062.67.176.1 to 62.67.191.25462.67.191.2554,094
6162.67.192.0/2062.67.192.1 to 62.67.207.25462.67.207.2554,094
6262.67.208.0/2062.67.208.1 to 62.67.223.25462.67.223.2554,094
6362.67.224.0/2062.67.224.1 to 62.67.239.25462.67.239.2554,094
6462.67.240.0/2062.67.240.1 to 62.67.255.25462.67.255.2554,094
6562.68.0.0/2062.68.0.1 to 62.68.15.25462.68.15.2554,094
6662.68.16.0/2062.68.16.1 to 62.68.31.25462.68.31.2554,094
6762.68.32.0/2062.68.32.1 to 62.68.47.25462.68.47.2554,094
6862.68.48.0/2062.68.48.1 to 62.68.63.25462.68.63.2554,094
6962.68.64.0/2062.68.64.1 to 62.68.79.25462.68.79.2554,094
7062.68.80.0/2062.68.80.1 to 62.68.95.25462.68.95.2554,094
7162.68.96.0/2062.68.96.1 to 62.68.111.25462.68.111.2554,094
7262.68.112.0/2062.68.112.1 to 62.68.127.25462.68.127.2554,094
7362.68.128.0/2062.68.128.1 to 62.68.143.25462.68.143.2554,094
7462.68.144.0/2062.68.144.1 to 62.68.159.25462.68.159.2554,094
7562.68.160.0/2062.68.160.1 to 62.68.175.25462.68.175.2554,094
7662.68.176.0/2062.68.176.1 to 62.68.191.25462.68.191.2554,094
7762.68.192.0/2062.68.192.1 to 62.68.207.25462.68.207.2554,094
7862.68.208.0/2062.68.208.1 to 62.68.223.25462.68.223.2554,094
7962.68.224.0/2062.68.224.1 to 62.68.239.25462.68.239.2554,094
8062.68.240.0/2062.68.240.1 to 62.68.255.25462.68.255.2554,094
8162.69.0.0/2062.69.0.1 to 62.69.15.25462.69.15.2554,094
8262.69.16.0/2062.69.16.1 to 62.69.31.25462.69.31.2554,094
8362.69.32.0/2062.69.32.1 to 62.69.47.25462.69.47.2554,094
8462.69.48.0/2062.69.48.1 to 62.69.63.25462.69.63.2554,094
8562.69.64.0/2062.69.64.1 to 62.69.79.25462.69.79.2554,094
8662.69.80.0/2062.69.80.1 to 62.69.95.25462.69.95.2554,094
8762.69.96.0/2062.69.96.1 to 62.69.111.25462.69.111.2554,094
8862.69.112.0/2062.69.112.1 to 62.69.127.25462.69.127.2554,094
8962.69.128.0/2062.69.128.1 to 62.69.143.25462.69.143.2554,094
9062.69.144.0/2062.69.144.1 to 62.69.159.25462.69.159.2554,094
9162.69.160.0/2062.69.160.1 to 62.69.175.25462.69.175.2554,094
9262.69.176.0/2062.69.176.1 to 62.69.191.25462.69.191.2554,094
9362.69.192.0/2062.69.192.1 to 62.69.207.25462.69.207.2554,094
9462.69.208.0/2062.69.208.1 to 62.69.223.25462.69.223.2554,094
9562.69.224.0/2062.69.224.1 to 62.69.239.25462.69.239.2554,094
9662.69.240.0/2062.69.240.1 to 62.69.255.25462.69.255.2554,094
9762.70.0.0/2062.70.0.1 to 62.70.15.25462.70.15.2554,094
9862.70.16.0/2062.70.16.1 to 62.70.31.25462.70.31.2554,094
9962.70.32.0/2062.70.32.1 to 62.70.47.25462.70.47.2554,094
10062.70.48.0/2062.70.48.1 to 62.70.63.25462.70.63.2554,094
10162.70.64.0/2062.70.64.1 to 62.70.79.25462.70.79.2554,094
10262.70.80.0/2062.70.80.1 to 62.70.95.25462.70.95.2554,094
10362.70.96.0/2062.70.96.1 to 62.70.111.25462.70.111.2554,094
10462.70.112.0/2062.70.112.1 to 62.70.127.25462.70.127.2554,094
10562.70.128.0/2062.70.128.1 to 62.70.143.25462.70.143.2554,094
10662.70.144.0/2062.70.144.1 to 62.70.159.25462.70.159.2554,094
10762.70.160.0/2062.70.160.1 to 62.70.175.25462.70.175.2554,094
10862.70.176.0/2062.70.176.1 to 62.70.191.25462.70.191.2554,094
10962.70.192.0/2062.70.192.1 to 62.70.207.25462.70.207.2554,094
11062.70.208.0/2062.70.208.1 to 62.70.223.25462.70.223.2554,094
11162.70.224.0/2062.70.224.1 to 62.70.239.25462.70.239.2554,094
11262.70.240.0/2062.70.240.1 to 62.70.255.25462.70.255.2554,094
11362.71.0.0/2062.71.0.1 to 62.71.15.25462.71.15.2554,094
11462.71.16.0/2062.71.16.1 to 62.71.31.25462.71.31.2554,094
11562.71.32.0/2062.71.32.1 to 62.71.47.25462.71.47.2554,094
11662.71.48.0/2062.71.48.1 to 62.71.63.25462.71.63.2554,094
11762.71.64.0/2062.71.64.1 to 62.71.79.25462.71.79.2554,094
11862.71.80.0/2062.71.80.1 to 62.71.95.25462.71.95.2554,094
11962.71.96.0/2062.71.96.1 to 62.71.111.25462.71.111.2554,094
12062.71.112.0/2062.71.112.1 to 62.71.127.25462.71.127.2554,094
12162.71.128.0/2062.71.128.1 to 62.71.143.25462.71.143.2554,094
12262.71.144.0/2062.71.144.1 to 62.71.159.25462.71.159.2554,094
12362.71.160.0/2062.71.160.1 to 62.71.175.25462.71.175.2554,094
12462.71.176.0/2062.71.176.1 to 62.71.191.25462.71.191.2554,094
12562.71.192.0/2062.71.192.1 to 62.71.207.25462.71.207.2554,094
12662.71.208.0/2062.71.208.1 to 62.71.223.25462.71.223.2554,094
12762.71.224.0/2062.71.224.1 to 62.71.239.25462.71.239.2554,094
12862.71.240.0/2062.71.240.1 to 62.71.255.25462.71.255.2554,094
12962.72.0.0/2062.72.0.1 to 62.72.15.25462.72.15.2554,094
13062.72.16.0/2062.72.16.1 to 62.72.31.25462.72.31.2554,094
13162.72.32.0/2062.72.32.1 to 62.72.47.25462.72.47.2554,094
13262.72.48.0/2062.72.48.1 to 62.72.63.25462.72.63.2554,094
13362.72.64.0/2062.72.64.1 to 62.72.79.25462.72.79.2554,094
13462.72.80.0/2062.72.80.1 to 62.72.95.25462.72.95.2554,094
13562.72.96.0/2062.72.96.1 to 62.72.111.25462.72.111.2554,094
13662.72.112.0/2062.72.112.1 to 62.72.127.25462.72.127.2554,094
13762.72.128.0/2062.72.128.1 to 62.72.143.25462.72.143.2554,094
13862.72.144.0/2062.72.144.1 to 62.72.159.25462.72.159.2554,094
13962.72.160.0/2062.72.160.1 to 62.72.175.25462.72.175.2554,094
14062.72.176.0/2062.72.176.1 to 62.72.191.25462.72.191.2554,094
14162.72.192.0/2062.72.192.1 to 62.72.207.25462.72.207.2554,094
14262.72.208.0/2062.72.208.1 to 62.72.223.25462.72.223.2554,094
14362.72.224.0/2062.72.224.1 to 62.72.239.25462.72.239.2554,094
14462.72.240.0/2062.72.240.1 to 62.72.255.25462.72.255.2554,094
14562.73.0.0/2062.73.0.1 to 62.73.15.25462.73.15.2554,094
14662.73.16.0/2062.73.16.1 to 62.73.31.25462.73.31.2554,094
14762.73.32.0/2062.73.32.1 to 62.73.47.25462.73.47.2554,094
14862.73.48.0/2062.73.48.1 to 62.73.63.25462.73.63.2554,094
14962.73.64.0/2062.73.64.1 to 62.73.79.25462.73.79.2554,094
15062.73.80.0/2062.73.80.1 to 62.73.95.25462.73.95.2554,094
15162.73.96.0/2062.73.96.1 to 62.73.111.25462.73.111.2554,094
15262.73.112.0/2062.73.112.1 to 62.73.127.25462.73.127.2554,094
15362.73.128.0/2062.73.128.1 to 62.73.143.25462.73.143.2554,094
15462.73.144.0/2062.73.144.1 to 62.73.159.25462.73.159.2554,094
15562.73.160.0/2062.73.160.1 to 62.73.175.25462.73.175.2554,094
15662.73.176.0/2062.73.176.1 to 62.73.191.25462.73.191.2554,094
15762.73.192.0/2062.73.192.1 to 62.73.207.25462.73.207.2554,094
15862.73.208.0/2062.73.208.1 to 62.73.223.25462.73.223.2554,094
15962.73.224.0/2062.73.224.1 to 62.73.239.25462.73.239.2554,094
16062.73.240.0/2062.73.240.1 to 62.73.255.25462.73.255.2554,094
16162.74.0.0/2062.74.0.1 to 62.74.15.25462.74.15.2554,094
16262.74.16.0/2062.74.16.1 to 62.74.31.25462.74.31.2554,094
16362.74.32.0/2062.74.32.1 to 62.74.47.25462.74.47.2554,094
16462.74.48.0/2062.74.48.1 to 62.74.63.25462.74.63.2554,094
16562.74.64.0/2062.74.64.1 to 62.74.79.25462.74.79.2554,094
16662.74.80.0/2062.74.80.1 to 62.74.95.25462.74.95.2554,094
16762.74.96.0/2062.74.96.1 to 62.74.111.25462.74.111.2554,094
16862.74.112.0/2062.74.112.1 to 62.74.127.25462.74.127.2554,094
16962.74.128.0/2062.74.128.1 to 62.74.143.25462.74.143.2554,094
17062.74.144.0/2062.74.144.1 to 62.74.159.25462.74.159.2554,094
17162.74.160.0/2062.74.160.1 to 62.74.175.25462.74.175.2554,094
17262.74.176.0/2062.74.176.1 to 62.74.191.25462.74.191.2554,094
17362.74.192.0/2062.74.192.1 to 62.74.207.25462.74.207.2554,094
17462.74.208.0/2062.74.208.1 to 62.74.223.25462.74.223.2554,094
17562.74.224.0/2062.74.224.1 to 62.74.239.25462.74.239.2554,094
17662.74.240.0/2062.74.240.1 to 62.74.255.25462.74.255.2554,094
17762.75.0.0/2062.75.0.1 to 62.75.15.25462.75.15.2554,094
17862.75.16.0/2062.75.16.1 to 62.75.31.25462.75.31.2554,094
17962.75.32.0/2062.75.32.1 to 62.75.47.25462.75.47.2554,094
18062.75.48.0/2062.75.48.1 to 62.75.63.25462.75.63.2554,094
18162.75.64.0/2062.75.64.1 to 62.75.79.25462.75.79.2554,094
18262.75.80.0/2062.75.80.1 to 62.75.95.25462.75.95.2554,094
18362.75.96.0/2062.75.96.1 to 62.75.111.25462.75.111.2554,094
18462.75.112.0/2062.75.112.1 to 62.75.127.25462.75.127.2554,094
18562.75.128.0/2062.75.128.1 to 62.75.143.25462.75.143.2554,094
18662.75.144.0/2062.75.144.1 to 62.75.159.25462.75.159.2554,094
18762.75.160.0/2062.75.160.1 to 62.75.175.25462.75.175.2554,094
18862.75.176.0/2062.75.176.1 to 62.75.191.25462.75.191.2554,094
18962.75.192.0/2062.75.192.1 to 62.75.207.25462.75.207.2554,094
19062.75.208.0/2062.75.208.1 to 62.75.223.25462.75.223.2554,094
19162.75.224.0/2062.75.224.1 to 62.75.239.25462.75.239.2554,094
19262.75.240.0/2062.75.240.1 to 62.75.255.25462.75.255.2554,094
19362.76.0.0/2062.76.0.1 to 62.76.15.25462.76.15.2554,094
19462.76.16.0/2062.76.16.1 to 62.76.31.25462.76.31.2554,094
19562.76.32.0/2062.76.32.1 to 62.76.47.25462.76.47.2554,094
19662.76.48.0/2062.76.48.1 to 62.76.63.25462.76.63.2554,094
19762.76.64.0/2062.76.64.1 to 62.76.79.25462.76.79.2554,094
19862.76.80.0/2062.76.80.1 to 62.76.95.25462.76.95.2554,094
19962.76.96.0/2062.76.96.1 to 62.76.111.25462.76.111.2554,094
20062.76.112.0/2062.76.112.1 to 62.76.127.25462.76.127.2554,094
20162.76.128.0/2062.76.128.1 to 62.76.143.25462.76.143.2554,094
20262.76.144.0/2062.76.144.1 to 62.76.159.25462.76.159.2554,094
20362.76.160.0/2062.76.160.1 to 62.76.175.25462.76.175.2554,094
20462.76.176.0/2062.76.176.1 to 62.76.191.25462.76.191.2554,094
20562.76.192.0/2062.76.192.1 to 62.76.207.25462.76.207.2554,094
20662.76.208.0/2062.76.208.1 to 62.76.223.25462.76.223.2554,094
20762.76.224.0/2062.76.224.1 to 62.76.239.25462.76.239.2554,094
20862.76.240.0/2062.76.240.1 to 62.76.255.25462.76.255.2554,094
20962.77.0.0/2062.77.0.1 to 62.77.15.25462.77.15.2554,094
21062.77.16.0/2062.77.16.1 to 62.77.31.25462.77.31.2554,094
21162.77.32.0/2062.77.32.1 to 62.77.47.25462.77.47.2554,094
21262.77.48.0/2062.77.48.1 to 62.77.63.25462.77.63.2554,094
21362.77.64.0/2062.77.64.1 to 62.77.79.25462.77.79.2554,094
21462.77.80.0/2062.77.80.1 to 62.77.95.25462.77.95.2554,094
21562.77.96.0/2062.77.96.1 to 62.77.111.25462.77.111.2554,094
21662.77.112.0/2062.77.112.1 to 62.77.127.25462.77.127.2554,094
21762.77.128.0/2062.77.128.1 to 62.77.143.25462.77.143.2554,094
21862.77.144.0/2062.77.144.1 to 62.77.159.25462.77.159.2554,094
21962.77.160.0/2062.77.160.1 to 62.77.175.25462.77.175.2554,094
22062.77.176.0/2062.77.176.1 to 62.77.191.25462.77.191.2554,094
22162.77.192.0/2062.77.192.1 to 62.77.207.25462.77.207.2554,094
22262.77.208.0/2062.77.208.1 to 62.77.223.25462.77.223.2554,094
22362.77.224.0/2062.77.224.1 to 62.77.239.25462.77.239.2554,094
22462.77.240.0/2062.77.240.1 to 62.77.255.25462.77.255.2554,094
22562.78.0.0/2062.78.0.1 to 62.78.15.25462.78.15.2554,094
22662.78.16.0/2062.78.16.1 to 62.78.31.25462.78.31.2554,094
22762.78.32.0/2062.78.32.1 to 62.78.47.25462.78.47.2554,094
22862.78.48.0/2062.78.48.1 to 62.78.63.25462.78.63.2554,094
22962.78.64.0/2062.78.64.1 to 62.78.79.25462.78.79.2554,094
23062.78.80.0/2062.78.80.1 to 62.78.95.25462.78.95.2554,094
23162.78.96.0/2062.78.96.1 to 62.78.111.25462.78.111.2554,094
23262.78.112.0/2062.78.112.1 to 62.78.127.25462.78.127.2554,094
23362.78.128.0/2062.78.128.1 to 62.78.143.25462.78.143.2554,094
23462.78.144.0/2062.78.144.1 to 62.78.159.25462.78.159.2554,094
23562.78.160.0/2062.78.160.1 to 62.78.175.25462.78.175.2554,094
23662.78.176.0/2062.78.176.1 to 62.78.191.25462.78.191.2554,094
23762.78.192.0/2062.78.192.1 to 62.78.207.25462.78.207.2554,094
23862.78.208.0/2062.78.208.1 to 62.78.223.25462.78.223.2554,094
23962.78.224.0/2062.78.224.1 to 62.78.239.25462.78.239.2554,094
24062.78.240.0/2062.78.240.1 to 62.78.255.25462.78.255.2554,094
24162.79.0.0/2062.79.0.1 to 62.79.15.25462.79.15.2554,094
24262.79.16.0/2062.79.16.1 to 62.79.31.25462.79.31.2554,094
24362.79.32.0/2062.79.32.1 to 62.79.47.25462.79.47.2554,094
24462.79.48.0/2062.79.48.1 to 62.79.63.25462.79.63.2554,094
24562.79.64.0/2062.79.64.1 to 62.79.79.25462.79.79.2554,094
24662.79.80.0/2062.79.80.1 to 62.79.95.25462.79.95.2554,094
24762.79.96.0/2062.79.96.1 to 62.79.111.25462.79.111.2554,094
24862.79.112.0/2062.79.112.1 to 62.79.127.25462.79.127.2554,094
24962.79.128.0/2062.79.128.1 to 62.79.143.25462.79.143.2554,094
25062.79.144.0/2062.79.144.1 to 62.79.159.25462.79.159.2554,094
25162.79.160.0/2062.79.160.1 to 62.79.175.25462.79.175.2554,094
25262.79.176.0/2062.79.176.1 to 62.79.191.25462.79.191.2554,094
25362.79.192.0/2062.79.192.1 to 62.79.207.25462.79.207.2554,094
25462.79.208.0/2062.79.208.1 to 62.79.223.25462.79.223.2554,094
25562.79.224.0/2062.79.224.1 to 62.79.239.25462.79.239.2554,094
25662.79.240.0/2062.79.240.1 to 62.79.255.25462.79.255.2554,094

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.