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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.

Network52.0.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
52.0.0.0
Broadcast address
52.63.255.255
First usable
52.0.0.1
Last usable
52.63.255.254
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 34000000 · Integer 872415232 to 876609535
Reverse DNS zones
0.52.in-addr.arpa
1.52.in-addr.arpa
2.52.in-addr.arpa
3.52.in-addr.arpa
4.52.in-addr.arpa
5.52.in-addr.arpa
6.52.in-addr.arpa
7.52.in-addr.arpa
8.52.in-addr.arpa
9.52.in-addr.arpa
10.52.in-addr.arpa
11.52.in-addr.arpa
12.52.in-addr.arpa
13.52.in-addr.arpa
14.52.in-addr.arpa
15.52.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
Address00110100.00000000.00000000.0000000052.0.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00110100.00000000.00000000.0000000052.0.0.0
Broadcast00110100.00111111.11111111.1111111152.63.255.255
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)

52.0.0.0/10 makes 1,024 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
152.0.0.0/2052.0.0.1 to 52.0.15.25452.0.15.2554,094
252.0.16.0/2052.0.16.1 to 52.0.31.25452.0.31.2554,094
352.0.32.0/2052.0.32.1 to 52.0.47.25452.0.47.2554,094
452.0.48.0/2052.0.48.1 to 52.0.63.25452.0.63.2554,094
552.0.64.0/2052.0.64.1 to 52.0.79.25452.0.79.2554,094
652.0.80.0/2052.0.80.1 to 52.0.95.25452.0.95.2554,094
752.0.96.0/2052.0.96.1 to 52.0.111.25452.0.111.2554,094
852.0.112.0/2052.0.112.1 to 52.0.127.25452.0.127.2554,094
952.0.128.0/2052.0.128.1 to 52.0.143.25452.0.143.2554,094
1052.0.144.0/2052.0.144.1 to 52.0.159.25452.0.159.2554,094
1152.0.160.0/2052.0.160.1 to 52.0.175.25452.0.175.2554,094
1252.0.176.0/2052.0.176.1 to 52.0.191.25452.0.191.2554,094
1352.0.192.0/2052.0.192.1 to 52.0.207.25452.0.207.2554,094
1452.0.208.0/2052.0.208.1 to 52.0.223.25452.0.223.2554,094
1552.0.224.0/2052.0.224.1 to 52.0.239.25452.0.239.2554,094
1652.0.240.0/2052.0.240.1 to 52.0.255.25452.0.255.2554,094
1752.1.0.0/2052.1.0.1 to 52.1.15.25452.1.15.2554,094
1852.1.16.0/2052.1.16.1 to 52.1.31.25452.1.31.2554,094
1952.1.32.0/2052.1.32.1 to 52.1.47.25452.1.47.2554,094
2052.1.48.0/2052.1.48.1 to 52.1.63.25452.1.63.2554,094
2152.1.64.0/2052.1.64.1 to 52.1.79.25452.1.79.2554,094
2252.1.80.0/2052.1.80.1 to 52.1.95.25452.1.95.2554,094
2352.1.96.0/2052.1.96.1 to 52.1.111.25452.1.111.2554,094
2452.1.112.0/2052.1.112.1 to 52.1.127.25452.1.127.2554,094
2552.1.128.0/2052.1.128.1 to 52.1.143.25452.1.143.2554,094
2652.1.144.0/2052.1.144.1 to 52.1.159.25452.1.159.2554,094
2752.1.160.0/2052.1.160.1 to 52.1.175.25452.1.175.2554,094
2852.1.176.0/2052.1.176.1 to 52.1.191.25452.1.191.2554,094
2952.1.192.0/2052.1.192.1 to 52.1.207.25452.1.207.2554,094
3052.1.208.0/2052.1.208.1 to 52.1.223.25452.1.223.2554,094
3152.1.224.0/2052.1.224.1 to 52.1.239.25452.1.239.2554,094
3252.1.240.0/2052.1.240.1 to 52.1.255.25452.1.255.2554,094
3352.2.0.0/2052.2.0.1 to 52.2.15.25452.2.15.2554,094
3452.2.16.0/2052.2.16.1 to 52.2.31.25452.2.31.2554,094
3552.2.32.0/2052.2.32.1 to 52.2.47.25452.2.47.2554,094
3652.2.48.0/2052.2.48.1 to 52.2.63.25452.2.63.2554,094
3752.2.64.0/2052.2.64.1 to 52.2.79.25452.2.79.2554,094
3852.2.80.0/2052.2.80.1 to 52.2.95.25452.2.95.2554,094
3952.2.96.0/2052.2.96.1 to 52.2.111.25452.2.111.2554,094
4052.2.112.0/2052.2.112.1 to 52.2.127.25452.2.127.2554,094
4152.2.128.0/2052.2.128.1 to 52.2.143.25452.2.143.2554,094
4252.2.144.0/2052.2.144.1 to 52.2.159.25452.2.159.2554,094
4352.2.160.0/2052.2.160.1 to 52.2.175.25452.2.175.2554,094
4452.2.176.0/2052.2.176.1 to 52.2.191.25452.2.191.2554,094
4552.2.192.0/2052.2.192.1 to 52.2.207.25452.2.207.2554,094
4652.2.208.0/2052.2.208.1 to 52.2.223.25452.2.223.2554,094
4752.2.224.0/2052.2.224.1 to 52.2.239.25452.2.239.2554,094
4852.2.240.0/2052.2.240.1 to 52.2.255.25452.2.255.2554,094
4952.3.0.0/2052.3.0.1 to 52.3.15.25452.3.15.2554,094
5052.3.16.0/2052.3.16.1 to 52.3.31.25452.3.31.2554,094
5152.3.32.0/2052.3.32.1 to 52.3.47.25452.3.47.2554,094
5252.3.48.0/2052.3.48.1 to 52.3.63.25452.3.63.2554,094
5352.3.64.0/2052.3.64.1 to 52.3.79.25452.3.79.2554,094
5452.3.80.0/2052.3.80.1 to 52.3.95.25452.3.95.2554,094
5552.3.96.0/2052.3.96.1 to 52.3.111.25452.3.111.2554,094
5652.3.112.0/2052.3.112.1 to 52.3.127.25452.3.127.2554,094
5752.3.128.0/2052.3.128.1 to 52.3.143.25452.3.143.2554,094
5852.3.144.0/2052.3.144.1 to 52.3.159.25452.3.159.2554,094
5952.3.160.0/2052.3.160.1 to 52.3.175.25452.3.175.2554,094
6052.3.176.0/2052.3.176.1 to 52.3.191.25452.3.191.2554,094
6152.3.192.0/2052.3.192.1 to 52.3.207.25452.3.207.2554,094
6252.3.208.0/2052.3.208.1 to 52.3.223.25452.3.223.2554,094
6352.3.224.0/2052.3.224.1 to 52.3.239.25452.3.239.2554,094
6452.3.240.0/2052.3.240.1 to 52.3.255.25452.3.255.2554,094
6552.4.0.0/2052.4.0.1 to 52.4.15.25452.4.15.2554,094
6652.4.16.0/2052.4.16.1 to 52.4.31.25452.4.31.2554,094
6752.4.32.0/2052.4.32.1 to 52.4.47.25452.4.47.2554,094
6852.4.48.0/2052.4.48.1 to 52.4.63.25452.4.63.2554,094
6952.4.64.0/2052.4.64.1 to 52.4.79.25452.4.79.2554,094
7052.4.80.0/2052.4.80.1 to 52.4.95.25452.4.95.2554,094
7152.4.96.0/2052.4.96.1 to 52.4.111.25452.4.111.2554,094
7252.4.112.0/2052.4.112.1 to 52.4.127.25452.4.127.2554,094
7352.4.128.0/2052.4.128.1 to 52.4.143.25452.4.143.2554,094
7452.4.144.0/2052.4.144.1 to 52.4.159.25452.4.159.2554,094
7552.4.160.0/2052.4.160.1 to 52.4.175.25452.4.175.2554,094
7652.4.176.0/2052.4.176.1 to 52.4.191.25452.4.191.2554,094
7752.4.192.0/2052.4.192.1 to 52.4.207.25452.4.207.2554,094
7852.4.208.0/2052.4.208.1 to 52.4.223.25452.4.223.2554,094
7952.4.224.0/2052.4.224.1 to 52.4.239.25452.4.239.2554,094
8052.4.240.0/2052.4.240.1 to 52.4.255.25452.4.255.2554,094
8152.5.0.0/2052.5.0.1 to 52.5.15.25452.5.15.2554,094
8252.5.16.0/2052.5.16.1 to 52.5.31.25452.5.31.2554,094
8352.5.32.0/2052.5.32.1 to 52.5.47.25452.5.47.2554,094
8452.5.48.0/2052.5.48.1 to 52.5.63.25452.5.63.2554,094
8552.5.64.0/2052.5.64.1 to 52.5.79.25452.5.79.2554,094
8652.5.80.0/2052.5.80.1 to 52.5.95.25452.5.95.2554,094
8752.5.96.0/2052.5.96.1 to 52.5.111.25452.5.111.2554,094
8852.5.112.0/2052.5.112.1 to 52.5.127.25452.5.127.2554,094
8952.5.128.0/2052.5.128.1 to 52.5.143.25452.5.143.2554,094
9052.5.144.0/2052.5.144.1 to 52.5.159.25452.5.159.2554,094
9152.5.160.0/2052.5.160.1 to 52.5.175.25452.5.175.2554,094
9252.5.176.0/2052.5.176.1 to 52.5.191.25452.5.191.2554,094
9352.5.192.0/2052.5.192.1 to 52.5.207.25452.5.207.2554,094
9452.5.208.0/2052.5.208.1 to 52.5.223.25452.5.223.2554,094
9552.5.224.0/2052.5.224.1 to 52.5.239.25452.5.239.2554,094
9652.5.240.0/2052.5.240.1 to 52.5.255.25452.5.255.2554,094
9752.6.0.0/2052.6.0.1 to 52.6.15.25452.6.15.2554,094
9852.6.16.0/2052.6.16.1 to 52.6.31.25452.6.31.2554,094
9952.6.32.0/2052.6.32.1 to 52.6.47.25452.6.47.2554,094
10052.6.48.0/2052.6.48.1 to 52.6.63.25452.6.63.2554,094
10152.6.64.0/2052.6.64.1 to 52.6.79.25452.6.79.2554,094
10252.6.80.0/2052.6.80.1 to 52.6.95.25452.6.95.2554,094
10352.6.96.0/2052.6.96.1 to 52.6.111.25452.6.111.2554,094
10452.6.112.0/2052.6.112.1 to 52.6.127.25452.6.127.2554,094
10552.6.128.0/2052.6.128.1 to 52.6.143.25452.6.143.2554,094
10652.6.144.0/2052.6.144.1 to 52.6.159.25452.6.159.2554,094
10752.6.160.0/2052.6.160.1 to 52.6.175.25452.6.175.2554,094
10852.6.176.0/2052.6.176.1 to 52.6.191.25452.6.191.2554,094
10952.6.192.0/2052.6.192.1 to 52.6.207.25452.6.207.2554,094
11052.6.208.0/2052.6.208.1 to 52.6.223.25452.6.223.2554,094
11152.6.224.0/2052.6.224.1 to 52.6.239.25452.6.239.2554,094
11252.6.240.0/2052.6.240.1 to 52.6.255.25452.6.255.2554,094
11352.7.0.0/2052.7.0.1 to 52.7.15.25452.7.15.2554,094
11452.7.16.0/2052.7.16.1 to 52.7.31.25452.7.31.2554,094
11552.7.32.0/2052.7.32.1 to 52.7.47.25452.7.47.2554,094
11652.7.48.0/2052.7.48.1 to 52.7.63.25452.7.63.2554,094
11752.7.64.0/2052.7.64.1 to 52.7.79.25452.7.79.2554,094
11852.7.80.0/2052.7.80.1 to 52.7.95.25452.7.95.2554,094
11952.7.96.0/2052.7.96.1 to 52.7.111.25452.7.111.2554,094
12052.7.112.0/2052.7.112.1 to 52.7.127.25452.7.127.2554,094
12152.7.128.0/2052.7.128.1 to 52.7.143.25452.7.143.2554,094
12252.7.144.0/2052.7.144.1 to 52.7.159.25452.7.159.2554,094
12352.7.160.0/2052.7.160.1 to 52.7.175.25452.7.175.2554,094
12452.7.176.0/2052.7.176.1 to 52.7.191.25452.7.191.2554,094
12552.7.192.0/2052.7.192.1 to 52.7.207.25452.7.207.2554,094
12652.7.208.0/2052.7.208.1 to 52.7.223.25452.7.223.2554,094
12752.7.224.0/2052.7.224.1 to 52.7.239.25452.7.239.2554,094
12852.7.240.0/2052.7.240.1 to 52.7.255.25452.7.255.2554,094
12952.8.0.0/2052.8.0.1 to 52.8.15.25452.8.15.2554,094
13052.8.16.0/2052.8.16.1 to 52.8.31.25452.8.31.2554,094
13152.8.32.0/2052.8.32.1 to 52.8.47.25452.8.47.2554,094
13252.8.48.0/2052.8.48.1 to 52.8.63.25452.8.63.2554,094
13352.8.64.0/2052.8.64.1 to 52.8.79.25452.8.79.2554,094
13452.8.80.0/2052.8.80.1 to 52.8.95.25452.8.95.2554,094
13552.8.96.0/2052.8.96.1 to 52.8.111.25452.8.111.2554,094
13652.8.112.0/2052.8.112.1 to 52.8.127.25452.8.127.2554,094
13752.8.128.0/2052.8.128.1 to 52.8.143.25452.8.143.2554,094
13852.8.144.0/2052.8.144.1 to 52.8.159.25452.8.159.2554,094
13952.8.160.0/2052.8.160.1 to 52.8.175.25452.8.175.2554,094
14052.8.176.0/2052.8.176.1 to 52.8.191.25452.8.191.2554,094
14152.8.192.0/2052.8.192.1 to 52.8.207.25452.8.207.2554,094
14252.8.208.0/2052.8.208.1 to 52.8.223.25452.8.223.2554,094
14352.8.224.0/2052.8.224.1 to 52.8.239.25452.8.239.2554,094
14452.8.240.0/2052.8.240.1 to 52.8.255.25452.8.255.2554,094
14552.9.0.0/2052.9.0.1 to 52.9.15.25452.9.15.2554,094
14652.9.16.0/2052.9.16.1 to 52.9.31.25452.9.31.2554,094
14752.9.32.0/2052.9.32.1 to 52.9.47.25452.9.47.2554,094
14852.9.48.0/2052.9.48.1 to 52.9.63.25452.9.63.2554,094
14952.9.64.0/2052.9.64.1 to 52.9.79.25452.9.79.2554,094
15052.9.80.0/2052.9.80.1 to 52.9.95.25452.9.95.2554,094
15152.9.96.0/2052.9.96.1 to 52.9.111.25452.9.111.2554,094
15252.9.112.0/2052.9.112.1 to 52.9.127.25452.9.127.2554,094
15352.9.128.0/2052.9.128.1 to 52.9.143.25452.9.143.2554,094
15452.9.144.0/2052.9.144.1 to 52.9.159.25452.9.159.2554,094
15552.9.160.0/2052.9.160.1 to 52.9.175.25452.9.175.2554,094
15652.9.176.0/2052.9.176.1 to 52.9.191.25452.9.191.2554,094
15752.9.192.0/2052.9.192.1 to 52.9.207.25452.9.207.2554,094
15852.9.208.0/2052.9.208.1 to 52.9.223.25452.9.223.2554,094
15952.9.224.0/2052.9.224.1 to 52.9.239.25452.9.239.2554,094
16052.9.240.0/2052.9.240.1 to 52.9.255.25452.9.255.2554,094
16152.10.0.0/2052.10.0.1 to 52.10.15.25452.10.15.2554,094
16252.10.16.0/2052.10.16.1 to 52.10.31.25452.10.31.2554,094
16352.10.32.0/2052.10.32.1 to 52.10.47.25452.10.47.2554,094
16452.10.48.0/2052.10.48.1 to 52.10.63.25452.10.63.2554,094
16552.10.64.0/2052.10.64.1 to 52.10.79.25452.10.79.2554,094
16652.10.80.0/2052.10.80.1 to 52.10.95.25452.10.95.2554,094
16752.10.96.0/2052.10.96.1 to 52.10.111.25452.10.111.2554,094
16852.10.112.0/2052.10.112.1 to 52.10.127.25452.10.127.2554,094
16952.10.128.0/2052.10.128.1 to 52.10.143.25452.10.143.2554,094
17052.10.144.0/2052.10.144.1 to 52.10.159.25452.10.159.2554,094
17152.10.160.0/2052.10.160.1 to 52.10.175.25452.10.175.2554,094
17252.10.176.0/2052.10.176.1 to 52.10.191.25452.10.191.2554,094
17352.10.192.0/2052.10.192.1 to 52.10.207.25452.10.207.2554,094
17452.10.208.0/2052.10.208.1 to 52.10.223.25452.10.223.2554,094
17552.10.224.0/2052.10.224.1 to 52.10.239.25452.10.239.2554,094
17652.10.240.0/2052.10.240.1 to 52.10.255.25452.10.255.2554,094
17752.11.0.0/2052.11.0.1 to 52.11.15.25452.11.15.2554,094
17852.11.16.0/2052.11.16.1 to 52.11.31.25452.11.31.2554,094
17952.11.32.0/2052.11.32.1 to 52.11.47.25452.11.47.2554,094
18052.11.48.0/2052.11.48.1 to 52.11.63.25452.11.63.2554,094
18152.11.64.0/2052.11.64.1 to 52.11.79.25452.11.79.2554,094
18252.11.80.0/2052.11.80.1 to 52.11.95.25452.11.95.2554,094
18352.11.96.0/2052.11.96.1 to 52.11.111.25452.11.111.2554,094
18452.11.112.0/2052.11.112.1 to 52.11.127.25452.11.127.2554,094
18552.11.128.0/2052.11.128.1 to 52.11.143.25452.11.143.2554,094
18652.11.144.0/2052.11.144.1 to 52.11.159.25452.11.159.2554,094
18752.11.160.0/2052.11.160.1 to 52.11.175.25452.11.175.2554,094
18852.11.176.0/2052.11.176.1 to 52.11.191.25452.11.191.2554,094
18952.11.192.0/2052.11.192.1 to 52.11.207.25452.11.207.2554,094
19052.11.208.0/2052.11.208.1 to 52.11.223.25452.11.223.2554,094
19152.11.224.0/2052.11.224.1 to 52.11.239.25452.11.239.2554,094
19252.11.240.0/2052.11.240.1 to 52.11.255.25452.11.255.2554,094
19352.12.0.0/2052.12.0.1 to 52.12.15.25452.12.15.2554,094
19452.12.16.0/2052.12.16.1 to 52.12.31.25452.12.31.2554,094
19552.12.32.0/2052.12.32.1 to 52.12.47.25452.12.47.2554,094
19652.12.48.0/2052.12.48.1 to 52.12.63.25452.12.63.2554,094
19752.12.64.0/2052.12.64.1 to 52.12.79.25452.12.79.2554,094
19852.12.80.0/2052.12.80.1 to 52.12.95.25452.12.95.2554,094
19952.12.96.0/2052.12.96.1 to 52.12.111.25452.12.111.2554,094
20052.12.112.0/2052.12.112.1 to 52.12.127.25452.12.127.2554,094
20152.12.128.0/2052.12.128.1 to 52.12.143.25452.12.143.2554,094
20252.12.144.0/2052.12.144.1 to 52.12.159.25452.12.159.2554,094
20352.12.160.0/2052.12.160.1 to 52.12.175.25452.12.175.2554,094
20452.12.176.0/2052.12.176.1 to 52.12.191.25452.12.191.2554,094
20552.12.192.0/2052.12.192.1 to 52.12.207.25452.12.207.2554,094
20652.12.208.0/2052.12.208.1 to 52.12.223.25452.12.223.2554,094
20752.12.224.0/2052.12.224.1 to 52.12.239.25452.12.239.2554,094
20852.12.240.0/2052.12.240.1 to 52.12.255.25452.12.255.2554,094
20952.13.0.0/2052.13.0.1 to 52.13.15.25452.13.15.2554,094
21052.13.16.0/2052.13.16.1 to 52.13.31.25452.13.31.2554,094
21152.13.32.0/2052.13.32.1 to 52.13.47.25452.13.47.2554,094
21252.13.48.0/2052.13.48.1 to 52.13.63.25452.13.63.2554,094
21352.13.64.0/2052.13.64.1 to 52.13.79.25452.13.79.2554,094
21452.13.80.0/2052.13.80.1 to 52.13.95.25452.13.95.2554,094
21552.13.96.0/2052.13.96.1 to 52.13.111.25452.13.111.2554,094
21652.13.112.0/2052.13.112.1 to 52.13.127.25452.13.127.2554,094
21752.13.128.0/2052.13.128.1 to 52.13.143.25452.13.143.2554,094
21852.13.144.0/2052.13.144.1 to 52.13.159.25452.13.159.2554,094
21952.13.160.0/2052.13.160.1 to 52.13.175.25452.13.175.2554,094
22052.13.176.0/2052.13.176.1 to 52.13.191.25452.13.191.2554,094
22152.13.192.0/2052.13.192.1 to 52.13.207.25452.13.207.2554,094
22252.13.208.0/2052.13.208.1 to 52.13.223.25452.13.223.2554,094
22352.13.224.0/2052.13.224.1 to 52.13.239.25452.13.239.2554,094
22452.13.240.0/2052.13.240.1 to 52.13.255.25452.13.255.2554,094
22552.14.0.0/2052.14.0.1 to 52.14.15.25452.14.15.2554,094
22652.14.16.0/2052.14.16.1 to 52.14.31.25452.14.31.2554,094
22752.14.32.0/2052.14.32.1 to 52.14.47.25452.14.47.2554,094
22852.14.48.0/2052.14.48.1 to 52.14.63.25452.14.63.2554,094
22952.14.64.0/2052.14.64.1 to 52.14.79.25452.14.79.2554,094
23052.14.80.0/2052.14.80.1 to 52.14.95.25452.14.95.2554,094
23152.14.96.0/2052.14.96.1 to 52.14.111.25452.14.111.2554,094
23252.14.112.0/2052.14.112.1 to 52.14.127.25452.14.127.2554,094
23352.14.128.0/2052.14.128.1 to 52.14.143.25452.14.143.2554,094
23452.14.144.0/2052.14.144.1 to 52.14.159.25452.14.159.2554,094
23552.14.160.0/2052.14.160.1 to 52.14.175.25452.14.175.2554,094
23652.14.176.0/2052.14.176.1 to 52.14.191.25452.14.191.2554,094
23752.14.192.0/2052.14.192.1 to 52.14.207.25452.14.207.2554,094
23852.14.208.0/2052.14.208.1 to 52.14.223.25452.14.223.2554,094
23952.14.224.0/2052.14.224.1 to 52.14.239.25452.14.239.2554,094
24052.14.240.0/2052.14.240.1 to 52.14.255.25452.14.255.2554,094
24152.15.0.0/2052.15.0.1 to 52.15.15.25452.15.15.2554,094
24252.15.16.0/2052.15.16.1 to 52.15.31.25452.15.31.2554,094
24352.15.32.0/2052.15.32.1 to 52.15.47.25452.15.47.2554,094
24452.15.48.0/2052.15.48.1 to 52.15.63.25452.15.63.2554,094
24552.15.64.0/2052.15.64.1 to 52.15.79.25452.15.79.2554,094
24652.15.80.0/2052.15.80.1 to 52.15.95.25452.15.95.2554,094
24752.15.96.0/2052.15.96.1 to 52.15.111.25452.15.111.2554,094
24852.15.112.0/2052.15.112.1 to 52.15.127.25452.15.127.2554,094
24952.15.128.0/2052.15.128.1 to 52.15.143.25452.15.143.2554,094
25052.15.144.0/2052.15.144.1 to 52.15.159.25452.15.159.2554,094
25152.15.160.0/2052.15.160.1 to 52.15.175.25452.15.175.2554,094
25252.15.176.0/2052.15.176.1 to 52.15.191.25452.15.191.2554,094
25352.15.192.0/2052.15.192.1 to 52.15.207.25452.15.207.2554,094
25452.15.208.0/2052.15.208.1 to 52.15.223.25452.15.223.2554,094
25552.15.224.0/2052.15.224.1 to 52.15.239.25452.15.239.2554,094
25652.15.240.0/2052.15.240.1 to 52.15.255.25452.15.255.2554,094

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.