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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.

Network53.0.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
53.0.0.0
Broadcast address
53.63.255.255
First usable
53.0.0.1
Last usable
53.63.255.254
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 35000000 · Integer 889192448 to 893386751
Reverse DNS zones
0.53.in-addr.arpa
1.53.in-addr.arpa
2.53.in-addr.arpa
3.53.in-addr.arpa
4.53.in-addr.arpa
5.53.in-addr.arpa
6.53.in-addr.arpa
7.53.in-addr.arpa
8.53.in-addr.arpa
9.53.in-addr.arpa
10.53.in-addr.arpa
11.53.in-addr.arpa
12.53.in-addr.arpa
13.53.in-addr.arpa
14.53.in-addr.arpa
15.53.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
Address00110101.00000000.00000000.0000000053.0.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00110101.00000000.00000000.0000000053.0.0.0
Broadcast00110101.00111111.11111111.1111111153.63.255.255
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)

53.0.0.0/10 makes 1,024 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
153.0.0.0/2053.0.0.1 to 53.0.15.25453.0.15.2554,094
253.0.16.0/2053.0.16.1 to 53.0.31.25453.0.31.2554,094
353.0.32.0/2053.0.32.1 to 53.0.47.25453.0.47.2554,094
453.0.48.0/2053.0.48.1 to 53.0.63.25453.0.63.2554,094
553.0.64.0/2053.0.64.1 to 53.0.79.25453.0.79.2554,094
653.0.80.0/2053.0.80.1 to 53.0.95.25453.0.95.2554,094
753.0.96.0/2053.0.96.1 to 53.0.111.25453.0.111.2554,094
853.0.112.0/2053.0.112.1 to 53.0.127.25453.0.127.2554,094
953.0.128.0/2053.0.128.1 to 53.0.143.25453.0.143.2554,094
1053.0.144.0/2053.0.144.1 to 53.0.159.25453.0.159.2554,094
1153.0.160.0/2053.0.160.1 to 53.0.175.25453.0.175.2554,094
1253.0.176.0/2053.0.176.1 to 53.0.191.25453.0.191.2554,094
1353.0.192.0/2053.0.192.1 to 53.0.207.25453.0.207.2554,094
1453.0.208.0/2053.0.208.1 to 53.0.223.25453.0.223.2554,094
1553.0.224.0/2053.0.224.1 to 53.0.239.25453.0.239.2554,094
1653.0.240.0/2053.0.240.1 to 53.0.255.25453.0.255.2554,094
1753.1.0.0/2053.1.0.1 to 53.1.15.25453.1.15.2554,094
1853.1.16.0/2053.1.16.1 to 53.1.31.25453.1.31.2554,094
1953.1.32.0/2053.1.32.1 to 53.1.47.25453.1.47.2554,094
2053.1.48.0/2053.1.48.1 to 53.1.63.25453.1.63.2554,094
2153.1.64.0/2053.1.64.1 to 53.1.79.25453.1.79.2554,094
2253.1.80.0/2053.1.80.1 to 53.1.95.25453.1.95.2554,094
2353.1.96.0/2053.1.96.1 to 53.1.111.25453.1.111.2554,094
2453.1.112.0/2053.1.112.1 to 53.1.127.25453.1.127.2554,094
2553.1.128.0/2053.1.128.1 to 53.1.143.25453.1.143.2554,094
2653.1.144.0/2053.1.144.1 to 53.1.159.25453.1.159.2554,094
2753.1.160.0/2053.1.160.1 to 53.1.175.25453.1.175.2554,094
2853.1.176.0/2053.1.176.1 to 53.1.191.25453.1.191.2554,094
2953.1.192.0/2053.1.192.1 to 53.1.207.25453.1.207.2554,094
3053.1.208.0/2053.1.208.1 to 53.1.223.25453.1.223.2554,094
3153.1.224.0/2053.1.224.1 to 53.1.239.25453.1.239.2554,094
3253.1.240.0/2053.1.240.1 to 53.1.255.25453.1.255.2554,094
3353.2.0.0/2053.2.0.1 to 53.2.15.25453.2.15.2554,094
3453.2.16.0/2053.2.16.1 to 53.2.31.25453.2.31.2554,094
3553.2.32.0/2053.2.32.1 to 53.2.47.25453.2.47.2554,094
3653.2.48.0/2053.2.48.1 to 53.2.63.25453.2.63.2554,094
3753.2.64.0/2053.2.64.1 to 53.2.79.25453.2.79.2554,094
3853.2.80.0/2053.2.80.1 to 53.2.95.25453.2.95.2554,094
3953.2.96.0/2053.2.96.1 to 53.2.111.25453.2.111.2554,094
4053.2.112.0/2053.2.112.1 to 53.2.127.25453.2.127.2554,094
4153.2.128.0/2053.2.128.1 to 53.2.143.25453.2.143.2554,094
4253.2.144.0/2053.2.144.1 to 53.2.159.25453.2.159.2554,094
4353.2.160.0/2053.2.160.1 to 53.2.175.25453.2.175.2554,094
4453.2.176.0/2053.2.176.1 to 53.2.191.25453.2.191.2554,094
4553.2.192.0/2053.2.192.1 to 53.2.207.25453.2.207.2554,094
4653.2.208.0/2053.2.208.1 to 53.2.223.25453.2.223.2554,094
4753.2.224.0/2053.2.224.1 to 53.2.239.25453.2.239.2554,094
4853.2.240.0/2053.2.240.1 to 53.2.255.25453.2.255.2554,094
4953.3.0.0/2053.3.0.1 to 53.3.15.25453.3.15.2554,094
5053.3.16.0/2053.3.16.1 to 53.3.31.25453.3.31.2554,094
5153.3.32.0/2053.3.32.1 to 53.3.47.25453.3.47.2554,094
5253.3.48.0/2053.3.48.1 to 53.3.63.25453.3.63.2554,094
5353.3.64.0/2053.3.64.1 to 53.3.79.25453.3.79.2554,094
5453.3.80.0/2053.3.80.1 to 53.3.95.25453.3.95.2554,094
5553.3.96.0/2053.3.96.1 to 53.3.111.25453.3.111.2554,094
5653.3.112.0/2053.3.112.1 to 53.3.127.25453.3.127.2554,094
5753.3.128.0/2053.3.128.1 to 53.3.143.25453.3.143.2554,094
5853.3.144.0/2053.3.144.1 to 53.3.159.25453.3.159.2554,094
5953.3.160.0/2053.3.160.1 to 53.3.175.25453.3.175.2554,094
6053.3.176.0/2053.3.176.1 to 53.3.191.25453.3.191.2554,094
6153.3.192.0/2053.3.192.1 to 53.3.207.25453.3.207.2554,094
6253.3.208.0/2053.3.208.1 to 53.3.223.25453.3.223.2554,094
6353.3.224.0/2053.3.224.1 to 53.3.239.25453.3.239.2554,094
6453.3.240.0/2053.3.240.1 to 53.3.255.25453.3.255.2554,094
6553.4.0.0/2053.4.0.1 to 53.4.15.25453.4.15.2554,094
6653.4.16.0/2053.4.16.1 to 53.4.31.25453.4.31.2554,094
6753.4.32.0/2053.4.32.1 to 53.4.47.25453.4.47.2554,094
6853.4.48.0/2053.4.48.1 to 53.4.63.25453.4.63.2554,094
6953.4.64.0/2053.4.64.1 to 53.4.79.25453.4.79.2554,094
7053.4.80.0/2053.4.80.1 to 53.4.95.25453.4.95.2554,094
7153.4.96.0/2053.4.96.1 to 53.4.111.25453.4.111.2554,094
7253.4.112.0/2053.4.112.1 to 53.4.127.25453.4.127.2554,094
7353.4.128.0/2053.4.128.1 to 53.4.143.25453.4.143.2554,094
7453.4.144.0/2053.4.144.1 to 53.4.159.25453.4.159.2554,094
7553.4.160.0/2053.4.160.1 to 53.4.175.25453.4.175.2554,094
7653.4.176.0/2053.4.176.1 to 53.4.191.25453.4.191.2554,094
7753.4.192.0/2053.4.192.1 to 53.4.207.25453.4.207.2554,094
7853.4.208.0/2053.4.208.1 to 53.4.223.25453.4.223.2554,094
7953.4.224.0/2053.4.224.1 to 53.4.239.25453.4.239.2554,094
8053.4.240.0/2053.4.240.1 to 53.4.255.25453.4.255.2554,094
8153.5.0.0/2053.5.0.1 to 53.5.15.25453.5.15.2554,094
8253.5.16.0/2053.5.16.1 to 53.5.31.25453.5.31.2554,094
8353.5.32.0/2053.5.32.1 to 53.5.47.25453.5.47.2554,094
8453.5.48.0/2053.5.48.1 to 53.5.63.25453.5.63.2554,094
8553.5.64.0/2053.5.64.1 to 53.5.79.25453.5.79.2554,094
8653.5.80.0/2053.5.80.1 to 53.5.95.25453.5.95.2554,094
8753.5.96.0/2053.5.96.1 to 53.5.111.25453.5.111.2554,094
8853.5.112.0/2053.5.112.1 to 53.5.127.25453.5.127.2554,094
8953.5.128.0/2053.5.128.1 to 53.5.143.25453.5.143.2554,094
9053.5.144.0/2053.5.144.1 to 53.5.159.25453.5.159.2554,094
9153.5.160.0/2053.5.160.1 to 53.5.175.25453.5.175.2554,094
9253.5.176.0/2053.5.176.1 to 53.5.191.25453.5.191.2554,094
9353.5.192.0/2053.5.192.1 to 53.5.207.25453.5.207.2554,094
9453.5.208.0/2053.5.208.1 to 53.5.223.25453.5.223.2554,094
9553.5.224.0/2053.5.224.1 to 53.5.239.25453.5.239.2554,094
9653.5.240.0/2053.5.240.1 to 53.5.255.25453.5.255.2554,094
9753.6.0.0/2053.6.0.1 to 53.6.15.25453.6.15.2554,094
9853.6.16.0/2053.6.16.1 to 53.6.31.25453.6.31.2554,094
9953.6.32.0/2053.6.32.1 to 53.6.47.25453.6.47.2554,094
10053.6.48.0/2053.6.48.1 to 53.6.63.25453.6.63.2554,094
10153.6.64.0/2053.6.64.1 to 53.6.79.25453.6.79.2554,094
10253.6.80.0/2053.6.80.1 to 53.6.95.25453.6.95.2554,094
10353.6.96.0/2053.6.96.1 to 53.6.111.25453.6.111.2554,094
10453.6.112.0/2053.6.112.1 to 53.6.127.25453.6.127.2554,094
10553.6.128.0/2053.6.128.1 to 53.6.143.25453.6.143.2554,094
10653.6.144.0/2053.6.144.1 to 53.6.159.25453.6.159.2554,094
10753.6.160.0/2053.6.160.1 to 53.6.175.25453.6.175.2554,094
10853.6.176.0/2053.6.176.1 to 53.6.191.25453.6.191.2554,094
10953.6.192.0/2053.6.192.1 to 53.6.207.25453.6.207.2554,094
11053.6.208.0/2053.6.208.1 to 53.6.223.25453.6.223.2554,094
11153.6.224.0/2053.6.224.1 to 53.6.239.25453.6.239.2554,094
11253.6.240.0/2053.6.240.1 to 53.6.255.25453.6.255.2554,094
11353.7.0.0/2053.7.0.1 to 53.7.15.25453.7.15.2554,094
11453.7.16.0/2053.7.16.1 to 53.7.31.25453.7.31.2554,094
11553.7.32.0/2053.7.32.1 to 53.7.47.25453.7.47.2554,094
11653.7.48.0/2053.7.48.1 to 53.7.63.25453.7.63.2554,094
11753.7.64.0/2053.7.64.1 to 53.7.79.25453.7.79.2554,094
11853.7.80.0/2053.7.80.1 to 53.7.95.25453.7.95.2554,094
11953.7.96.0/2053.7.96.1 to 53.7.111.25453.7.111.2554,094
12053.7.112.0/2053.7.112.1 to 53.7.127.25453.7.127.2554,094
12153.7.128.0/2053.7.128.1 to 53.7.143.25453.7.143.2554,094
12253.7.144.0/2053.7.144.1 to 53.7.159.25453.7.159.2554,094
12353.7.160.0/2053.7.160.1 to 53.7.175.25453.7.175.2554,094
12453.7.176.0/2053.7.176.1 to 53.7.191.25453.7.191.2554,094
12553.7.192.0/2053.7.192.1 to 53.7.207.25453.7.207.2554,094
12653.7.208.0/2053.7.208.1 to 53.7.223.25453.7.223.2554,094
12753.7.224.0/2053.7.224.1 to 53.7.239.25453.7.239.2554,094
12853.7.240.0/2053.7.240.1 to 53.7.255.25453.7.255.2554,094
12953.8.0.0/2053.8.0.1 to 53.8.15.25453.8.15.2554,094
13053.8.16.0/2053.8.16.1 to 53.8.31.25453.8.31.2554,094
13153.8.32.0/2053.8.32.1 to 53.8.47.25453.8.47.2554,094
13253.8.48.0/2053.8.48.1 to 53.8.63.25453.8.63.2554,094
13353.8.64.0/2053.8.64.1 to 53.8.79.25453.8.79.2554,094
13453.8.80.0/2053.8.80.1 to 53.8.95.25453.8.95.2554,094
13553.8.96.0/2053.8.96.1 to 53.8.111.25453.8.111.2554,094
13653.8.112.0/2053.8.112.1 to 53.8.127.25453.8.127.2554,094
13753.8.128.0/2053.8.128.1 to 53.8.143.25453.8.143.2554,094
13853.8.144.0/2053.8.144.1 to 53.8.159.25453.8.159.2554,094
13953.8.160.0/2053.8.160.1 to 53.8.175.25453.8.175.2554,094
14053.8.176.0/2053.8.176.1 to 53.8.191.25453.8.191.2554,094
14153.8.192.0/2053.8.192.1 to 53.8.207.25453.8.207.2554,094
14253.8.208.0/2053.8.208.1 to 53.8.223.25453.8.223.2554,094
14353.8.224.0/2053.8.224.1 to 53.8.239.25453.8.239.2554,094
14453.8.240.0/2053.8.240.1 to 53.8.255.25453.8.255.2554,094
14553.9.0.0/2053.9.0.1 to 53.9.15.25453.9.15.2554,094
14653.9.16.0/2053.9.16.1 to 53.9.31.25453.9.31.2554,094
14753.9.32.0/2053.9.32.1 to 53.9.47.25453.9.47.2554,094
14853.9.48.0/2053.9.48.1 to 53.9.63.25453.9.63.2554,094
14953.9.64.0/2053.9.64.1 to 53.9.79.25453.9.79.2554,094
15053.9.80.0/2053.9.80.1 to 53.9.95.25453.9.95.2554,094
15153.9.96.0/2053.9.96.1 to 53.9.111.25453.9.111.2554,094
15253.9.112.0/2053.9.112.1 to 53.9.127.25453.9.127.2554,094
15353.9.128.0/2053.9.128.1 to 53.9.143.25453.9.143.2554,094
15453.9.144.0/2053.9.144.1 to 53.9.159.25453.9.159.2554,094
15553.9.160.0/2053.9.160.1 to 53.9.175.25453.9.175.2554,094
15653.9.176.0/2053.9.176.1 to 53.9.191.25453.9.191.2554,094
15753.9.192.0/2053.9.192.1 to 53.9.207.25453.9.207.2554,094
15853.9.208.0/2053.9.208.1 to 53.9.223.25453.9.223.2554,094
15953.9.224.0/2053.9.224.1 to 53.9.239.25453.9.239.2554,094
16053.9.240.0/2053.9.240.1 to 53.9.255.25453.9.255.2554,094
16153.10.0.0/2053.10.0.1 to 53.10.15.25453.10.15.2554,094
16253.10.16.0/2053.10.16.1 to 53.10.31.25453.10.31.2554,094
16353.10.32.0/2053.10.32.1 to 53.10.47.25453.10.47.2554,094
16453.10.48.0/2053.10.48.1 to 53.10.63.25453.10.63.2554,094
16553.10.64.0/2053.10.64.1 to 53.10.79.25453.10.79.2554,094
16653.10.80.0/2053.10.80.1 to 53.10.95.25453.10.95.2554,094
16753.10.96.0/2053.10.96.1 to 53.10.111.25453.10.111.2554,094
16853.10.112.0/2053.10.112.1 to 53.10.127.25453.10.127.2554,094
16953.10.128.0/2053.10.128.1 to 53.10.143.25453.10.143.2554,094
17053.10.144.0/2053.10.144.1 to 53.10.159.25453.10.159.2554,094
17153.10.160.0/2053.10.160.1 to 53.10.175.25453.10.175.2554,094
17253.10.176.0/2053.10.176.1 to 53.10.191.25453.10.191.2554,094
17353.10.192.0/2053.10.192.1 to 53.10.207.25453.10.207.2554,094
17453.10.208.0/2053.10.208.1 to 53.10.223.25453.10.223.2554,094
17553.10.224.0/2053.10.224.1 to 53.10.239.25453.10.239.2554,094
17653.10.240.0/2053.10.240.1 to 53.10.255.25453.10.255.2554,094
17753.11.0.0/2053.11.0.1 to 53.11.15.25453.11.15.2554,094
17853.11.16.0/2053.11.16.1 to 53.11.31.25453.11.31.2554,094
17953.11.32.0/2053.11.32.1 to 53.11.47.25453.11.47.2554,094
18053.11.48.0/2053.11.48.1 to 53.11.63.25453.11.63.2554,094
18153.11.64.0/2053.11.64.1 to 53.11.79.25453.11.79.2554,094
18253.11.80.0/2053.11.80.1 to 53.11.95.25453.11.95.2554,094
18353.11.96.0/2053.11.96.1 to 53.11.111.25453.11.111.2554,094
18453.11.112.0/2053.11.112.1 to 53.11.127.25453.11.127.2554,094
18553.11.128.0/2053.11.128.1 to 53.11.143.25453.11.143.2554,094
18653.11.144.0/2053.11.144.1 to 53.11.159.25453.11.159.2554,094
18753.11.160.0/2053.11.160.1 to 53.11.175.25453.11.175.2554,094
18853.11.176.0/2053.11.176.1 to 53.11.191.25453.11.191.2554,094
18953.11.192.0/2053.11.192.1 to 53.11.207.25453.11.207.2554,094
19053.11.208.0/2053.11.208.1 to 53.11.223.25453.11.223.2554,094
19153.11.224.0/2053.11.224.1 to 53.11.239.25453.11.239.2554,094
19253.11.240.0/2053.11.240.1 to 53.11.255.25453.11.255.2554,094
19353.12.0.0/2053.12.0.1 to 53.12.15.25453.12.15.2554,094
19453.12.16.0/2053.12.16.1 to 53.12.31.25453.12.31.2554,094
19553.12.32.0/2053.12.32.1 to 53.12.47.25453.12.47.2554,094
19653.12.48.0/2053.12.48.1 to 53.12.63.25453.12.63.2554,094
19753.12.64.0/2053.12.64.1 to 53.12.79.25453.12.79.2554,094
19853.12.80.0/2053.12.80.1 to 53.12.95.25453.12.95.2554,094
19953.12.96.0/2053.12.96.1 to 53.12.111.25453.12.111.2554,094
20053.12.112.0/2053.12.112.1 to 53.12.127.25453.12.127.2554,094
20153.12.128.0/2053.12.128.1 to 53.12.143.25453.12.143.2554,094
20253.12.144.0/2053.12.144.1 to 53.12.159.25453.12.159.2554,094
20353.12.160.0/2053.12.160.1 to 53.12.175.25453.12.175.2554,094
20453.12.176.0/2053.12.176.1 to 53.12.191.25453.12.191.2554,094
20553.12.192.0/2053.12.192.1 to 53.12.207.25453.12.207.2554,094
20653.12.208.0/2053.12.208.1 to 53.12.223.25453.12.223.2554,094
20753.12.224.0/2053.12.224.1 to 53.12.239.25453.12.239.2554,094
20853.12.240.0/2053.12.240.1 to 53.12.255.25453.12.255.2554,094
20953.13.0.0/2053.13.0.1 to 53.13.15.25453.13.15.2554,094
21053.13.16.0/2053.13.16.1 to 53.13.31.25453.13.31.2554,094
21153.13.32.0/2053.13.32.1 to 53.13.47.25453.13.47.2554,094
21253.13.48.0/2053.13.48.1 to 53.13.63.25453.13.63.2554,094
21353.13.64.0/2053.13.64.1 to 53.13.79.25453.13.79.2554,094
21453.13.80.0/2053.13.80.1 to 53.13.95.25453.13.95.2554,094
21553.13.96.0/2053.13.96.1 to 53.13.111.25453.13.111.2554,094
21653.13.112.0/2053.13.112.1 to 53.13.127.25453.13.127.2554,094
21753.13.128.0/2053.13.128.1 to 53.13.143.25453.13.143.2554,094
21853.13.144.0/2053.13.144.1 to 53.13.159.25453.13.159.2554,094
21953.13.160.0/2053.13.160.1 to 53.13.175.25453.13.175.2554,094
22053.13.176.0/2053.13.176.1 to 53.13.191.25453.13.191.2554,094
22153.13.192.0/2053.13.192.1 to 53.13.207.25453.13.207.2554,094
22253.13.208.0/2053.13.208.1 to 53.13.223.25453.13.223.2554,094
22353.13.224.0/2053.13.224.1 to 53.13.239.25453.13.239.2554,094
22453.13.240.0/2053.13.240.1 to 53.13.255.25453.13.255.2554,094
22553.14.0.0/2053.14.0.1 to 53.14.15.25453.14.15.2554,094
22653.14.16.0/2053.14.16.1 to 53.14.31.25453.14.31.2554,094
22753.14.32.0/2053.14.32.1 to 53.14.47.25453.14.47.2554,094
22853.14.48.0/2053.14.48.1 to 53.14.63.25453.14.63.2554,094
22953.14.64.0/2053.14.64.1 to 53.14.79.25453.14.79.2554,094
23053.14.80.0/2053.14.80.1 to 53.14.95.25453.14.95.2554,094
23153.14.96.0/2053.14.96.1 to 53.14.111.25453.14.111.2554,094
23253.14.112.0/2053.14.112.1 to 53.14.127.25453.14.127.2554,094
23353.14.128.0/2053.14.128.1 to 53.14.143.25453.14.143.2554,094
23453.14.144.0/2053.14.144.1 to 53.14.159.25453.14.159.2554,094
23553.14.160.0/2053.14.160.1 to 53.14.175.25453.14.175.2554,094
23653.14.176.0/2053.14.176.1 to 53.14.191.25453.14.191.2554,094
23753.14.192.0/2053.14.192.1 to 53.14.207.25453.14.207.2554,094
23853.14.208.0/2053.14.208.1 to 53.14.223.25453.14.223.2554,094
23953.14.224.0/2053.14.224.1 to 53.14.239.25453.14.239.2554,094
24053.14.240.0/2053.14.240.1 to 53.14.255.25453.14.255.2554,094
24153.15.0.0/2053.15.0.1 to 53.15.15.25453.15.15.2554,094
24253.15.16.0/2053.15.16.1 to 53.15.31.25453.15.31.2554,094
24353.15.32.0/2053.15.32.1 to 53.15.47.25453.15.47.2554,094
24453.15.48.0/2053.15.48.1 to 53.15.63.25453.15.63.2554,094
24553.15.64.0/2053.15.64.1 to 53.15.79.25453.15.79.2554,094
24653.15.80.0/2053.15.80.1 to 53.15.95.25453.15.95.2554,094
24753.15.96.0/2053.15.96.1 to 53.15.111.25453.15.111.2554,094
24853.15.112.0/2053.15.112.1 to 53.15.127.25453.15.127.2554,094
24953.15.128.0/2053.15.128.1 to 53.15.143.25453.15.143.2554,094
25053.15.144.0/2053.15.144.1 to 53.15.159.25453.15.159.2554,094
25153.15.160.0/2053.15.160.1 to 53.15.175.25453.15.175.2554,094
25253.15.176.0/2053.15.176.1 to 53.15.191.25453.15.191.2554,094
25353.15.192.0/2053.15.192.1 to 53.15.207.25453.15.207.2554,094
25453.15.208.0/2053.15.208.1 to 53.15.223.25453.15.223.2554,094
25553.15.224.0/2053.15.224.1 to 53.15.239.25453.15.239.2554,094
25653.15.240.0/2053.15.240.1 to 53.15.255.25453.15.255.2554,094

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.