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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.

Network52.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
52.0.0.0
Broadcast address
53.255.255.255
First usable
52.0.0.1
Last usable
53.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 34000000 · Integer 872415232 to 905969663
Reverse DNS zones
52.in-addr.arpa
53.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110100.00000000.00000000.0000000052.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network00110100.00000000.00000000.0000000052.0.0.0
Broadcast00110101.11111111.11111111.1111111153.255.255.255
Split into smaller subnets/19
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

52.0.0.0/7 makes 4,096 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
152.0.0.0/1952.0.0.1 to 52.0.31.25452.0.31.2558,190
252.0.32.0/1952.0.32.1 to 52.0.63.25452.0.63.2558,190
352.0.64.0/1952.0.64.1 to 52.0.95.25452.0.95.2558,190
452.0.96.0/1952.0.96.1 to 52.0.127.25452.0.127.2558,190
552.0.128.0/1952.0.128.1 to 52.0.159.25452.0.159.2558,190
652.0.160.0/1952.0.160.1 to 52.0.191.25452.0.191.2558,190
752.0.192.0/1952.0.192.1 to 52.0.223.25452.0.223.2558,190
852.0.224.0/1952.0.224.1 to 52.0.255.25452.0.255.2558,190
952.1.0.0/1952.1.0.1 to 52.1.31.25452.1.31.2558,190
1052.1.32.0/1952.1.32.1 to 52.1.63.25452.1.63.2558,190
1152.1.64.0/1952.1.64.1 to 52.1.95.25452.1.95.2558,190
1252.1.96.0/1952.1.96.1 to 52.1.127.25452.1.127.2558,190
1352.1.128.0/1952.1.128.1 to 52.1.159.25452.1.159.2558,190
1452.1.160.0/1952.1.160.1 to 52.1.191.25452.1.191.2558,190
1552.1.192.0/1952.1.192.1 to 52.1.223.25452.1.223.2558,190
1652.1.224.0/1952.1.224.1 to 52.1.255.25452.1.255.2558,190
1752.2.0.0/1952.2.0.1 to 52.2.31.25452.2.31.2558,190
1852.2.32.0/1952.2.32.1 to 52.2.63.25452.2.63.2558,190
1952.2.64.0/1952.2.64.1 to 52.2.95.25452.2.95.2558,190
2052.2.96.0/1952.2.96.1 to 52.2.127.25452.2.127.2558,190
2152.2.128.0/1952.2.128.1 to 52.2.159.25452.2.159.2558,190
2252.2.160.0/1952.2.160.1 to 52.2.191.25452.2.191.2558,190
2352.2.192.0/1952.2.192.1 to 52.2.223.25452.2.223.2558,190
2452.2.224.0/1952.2.224.1 to 52.2.255.25452.2.255.2558,190
2552.3.0.0/1952.3.0.1 to 52.3.31.25452.3.31.2558,190
2652.3.32.0/1952.3.32.1 to 52.3.63.25452.3.63.2558,190
2752.3.64.0/1952.3.64.1 to 52.3.95.25452.3.95.2558,190
2852.3.96.0/1952.3.96.1 to 52.3.127.25452.3.127.2558,190
2952.3.128.0/1952.3.128.1 to 52.3.159.25452.3.159.2558,190
3052.3.160.0/1952.3.160.1 to 52.3.191.25452.3.191.2558,190
3152.3.192.0/1952.3.192.1 to 52.3.223.25452.3.223.2558,190
3252.3.224.0/1952.3.224.1 to 52.3.255.25452.3.255.2558,190
3352.4.0.0/1952.4.0.1 to 52.4.31.25452.4.31.2558,190
3452.4.32.0/1952.4.32.1 to 52.4.63.25452.4.63.2558,190
3552.4.64.0/1952.4.64.1 to 52.4.95.25452.4.95.2558,190
3652.4.96.0/1952.4.96.1 to 52.4.127.25452.4.127.2558,190
3752.4.128.0/1952.4.128.1 to 52.4.159.25452.4.159.2558,190
3852.4.160.0/1952.4.160.1 to 52.4.191.25452.4.191.2558,190
3952.4.192.0/1952.4.192.1 to 52.4.223.25452.4.223.2558,190
4052.4.224.0/1952.4.224.1 to 52.4.255.25452.4.255.2558,190
4152.5.0.0/1952.5.0.1 to 52.5.31.25452.5.31.2558,190
4252.5.32.0/1952.5.32.1 to 52.5.63.25452.5.63.2558,190
4352.5.64.0/1952.5.64.1 to 52.5.95.25452.5.95.2558,190
4452.5.96.0/1952.5.96.1 to 52.5.127.25452.5.127.2558,190
4552.5.128.0/1952.5.128.1 to 52.5.159.25452.5.159.2558,190
4652.5.160.0/1952.5.160.1 to 52.5.191.25452.5.191.2558,190
4752.5.192.0/1952.5.192.1 to 52.5.223.25452.5.223.2558,190
4852.5.224.0/1952.5.224.1 to 52.5.255.25452.5.255.2558,190
4952.6.0.0/1952.6.0.1 to 52.6.31.25452.6.31.2558,190
5052.6.32.0/1952.6.32.1 to 52.6.63.25452.6.63.2558,190
5152.6.64.0/1952.6.64.1 to 52.6.95.25452.6.95.2558,190
5252.6.96.0/1952.6.96.1 to 52.6.127.25452.6.127.2558,190
5352.6.128.0/1952.6.128.1 to 52.6.159.25452.6.159.2558,190
5452.6.160.0/1952.6.160.1 to 52.6.191.25452.6.191.2558,190
5552.6.192.0/1952.6.192.1 to 52.6.223.25452.6.223.2558,190
5652.6.224.0/1952.6.224.1 to 52.6.255.25452.6.255.2558,190
5752.7.0.0/1952.7.0.1 to 52.7.31.25452.7.31.2558,190
5852.7.32.0/1952.7.32.1 to 52.7.63.25452.7.63.2558,190
5952.7.64.0/1952.7.64.1 to 52.7.95.25452.7.95.2558,190
6052.7.96.0/1952.7.96.1 to 52.7.127.25452.7.127.2558,190
6152.7.128.0/1952.7.128.1 to 52.7.159.25452.7.159.2558,190
6252.7.160.0/1952.7.160.1 to 52.7.191.25452.7.191.2558,190
6352.7.192.0/1952.7.192.1 to 52.7.223.25452.7.223.2558,190
6452.7.224.0/1952.7.224.1 to 52.7.255.25452.7.255.2558,190
6552.8.0.0/1952.8.0.1 to 52.8.31.25452.8.31.2558,190
6652.8.32.0/1952.8.32.1 to 52.8.63.25452.8.63.2558,190
6752.8.64.0/1952.8.64.1 to 52.8.95.25452.8.95.2558,190
6852.8.96.0/1952.8.96.1 to 52.8.127.25452.8.127.2558,190
6952.8.128.0/1952.8.128.1 to 52.8.159.25452.8.159.2558,190
7052.8.160.0/1952.8.160.1 to 52.8.191.25452.8.191.2558,190
7152.8.192.0/1952.8.192.1 to 52.8.223.25452.8.223.2558,190
7252.8.224.0/1952.8.224.1 to 52.8.255.25452.8.255.2558,190
7352.9.0.0/1952.9.0.1 to 52.9.31.25452.9.31.2558,190
7452.9.32.0/1952.9.32.1 to 52.9.63.25452.9.63.2558,190
7552.9.64.0/1952.9.64.1 to 52.9.95.25452.9.95.2558,190
7652.9.96.0/1952.9.96.1 to 52.9.127.25452.9.127.2558,190
7752.9.128.0/1952.9.128.1 to 52.9.159.25452.9.159.2558,190
7852.9.160.0/1952.9.160.1 to 52.9.191.25452.9.191.2558,190
7952.9.192.0/1952.9.192.1 to 52.9.223.25452.9.223.2558,190
8052.9.224.0/1952.9.224.1 to 52.9.255.25452.9.255.2558,190
8152.10.0.0/1952.10.0.1 to 52.10.31.25452.10.31.2558,190
8252.10.32.0/1952.10.32.1 to 52.10.63.25452.10.63.2558,190
8352.10.64.0/1952.10.64.1 to 52.10.95.25452.10.95.2558,190
8452.10.96.0/1952.10.96.1 to 52.10.127.25452.10.127.2558,190
8552.10.128.0/1952.10.128.1 to 52.10.159.25452.10.159.2558,190
8652.10.160.0/1952.10.160.1 to 52.10.191.25452.10.191.2558,190
8752.10.192.0/1952.10.192.1 to 52.10.223.25452.10.223.2558,190
8852.10.224.0/1952.10.224.1 to 52.10.255.25452.10.255.2558,190
8952.11.0.0/1952.11.0.1 to 52.11.31.25452.11.31.2558,190
9052.11.32.0/1952.11.32.1 to 52.11.63.25452.11.63.2558,190
9152.11.64.0/1952.11.64.1 to 52.11.95.25452.11.95.2558,190
9252.11.96.0/1952.11.96.1 to 52.11.127.25452.11.127.2558,190
9352.11.128.0/1952.11.128.1 to 52.11.159.25452.11.159.2558,190
9452.11.160.0/1952.11.160.1 to 52.11.191.25452.11.191.2558,190
9552.11.192.0/1952.11.192.1 to 52.11.223.25452.11.223.2558,190
9652.11.224.0/1952.11.224.1 to 52.11.255.25452.11.255.2558,190
9752.12.0.0/1952.12.0.1 to 52.12.31.25452.12.31.2558,190
9852.12.32.0/1952.12.32.1 to 52.12.63.25452.12.63.2558,190
9952.12.64.0/1952.12.64.1 to 52.12.95.25452.12.95.2558,190
10052.12.96.0/1952.12.96.1 to 52.12.127.25452.12.127.2558,190
10152.12.128.0/1952.12.128.1 to 52.12.159.25452.12.159.2558,190
10252.12.160.0/1952.12.160.1 to 52.12.191.25452.12.191.2558,190
10352.12.192.0/1952.12.192.1 to 52.12.223.25452.12.223.2558,190
10452.12.224.0/1952.12.224.1 to 52.12.255.25452.12.255.2558,190
10552.13.0.0/1952.13.0.1 to 52.13.31.25452.13.31.2558,190
10652.13.32.0/1952.13.32.1 to 52.13.63.25452.13.63.2558,190
10752.13.64.0/1952.13.64.1 to 52.13.95.25452.13.95.2558,190
10852.13.96.0/1952.13.96.1 to 52.13.127.25452.13.127.2558,190
10952.13.128.0/1952.13.128.1 to 52.13.159.25452.13.159.2558,190
11052.13.160.0/1952.13.160.1 to 52.13.191.25452.13.191.2558,190
11152.13.192.0/1952.13.192.1 to 52.13.223.25452.13.223.2558,190
11252.13.224.0/1952.13.224.1 to 52.13.255.25452.13.255.2558,190
11352.14.0.0/1952.14.0.1 to 52.14.31.25452.14.31.2558,190
11452.14.32.0/1952.14.32.1 to 52.14.63.25452.14.63.2558,190
11552.14.64.0/1952.14.64.1 to 52.14.95.25452.14.95.2558,190
11652.14.96.0/1952.14.96.1 to 52.14.127.25452.14.127.2558,190
11752.14.128.0/1952.14.128.1 to 52.14.159.25452.14.159.2558,190
11852.14.160.0/1952.14.160.1 to 52.14.191.25452.14.191.2558,190
11952.14.192.0/1952.14.192.1 to 52.14.223.25452.14.223.2558,190
12052.14.224.0/1952.14.224.1 to 52.14.255.25452.14.255.2558,190
12152.15.0.0/1952.15.0.1 to 52.15.31.25452.15.31.2558,190
12252.15.32.0/1952.15.32.1 to 52.15.63.25452.15.63.2558,190
12352.15.64.0/1952.15.64.1 to 52.15.95.25452.15.95.2558,190
12452.15.96.0/1952.15.96.1 to 52.15.127.25452.15.127.2558,190
12552.15.128.0/1952.15.128.1 to 52.15.159.25452.15.159.2558,190
12652.15.160.0/1952.15.160.1 to 52.15.191.25452.15.191.2558,190
12752.15.192.0/1952.15.192.1 to 52.15.223.25452.15.223.2558,190
12852.15.224.0/1952.15.224.1 to 52.15.255.25452.15.255.2558,190
12952.16.0.0/1952.16.0.1 to 52.16.31.25452.16.31.2558,190
13052.16.32.0/1952.16.32.1 to 52.16.63.25452.16.63.2558,190
13152.16.64.0/1952.16.64.1 to 52.16.95.25452.16.95.2558,190
13252.16.96.0/1952.16.96.1 to 52.16.127.25452.16.127.2558,190
13352.16.128.0/1952.16.128.1 to 52.16.159.25452.16.159.2558,190
13452.16.160.0/1952.16.160.1 to 52.16.191.25452.16.191.2558,190
13552.16.192.0/1952.16.192.1 to 52.16.223.25452.16.223.2558,190
13652.16.224.0/1952.16.224.1 to 52.16.255.25452.16.255.2558,190
13752.17.0.0/1952.17.0.1 to 52.17.31.25452.17.31.2558,190
13852.17.32.0/1952.17.32.1 to 52.17.63.25452.17.63.2558,190
13952.17.64.0/1952.17.64.1 to 52.17.95.25452.17.95.2558,190
14052.17.96.0/1952.17.96.1 to 52.17.127.25452.17.127.2558,190
14152.17.128.0/1952.17.128.1 to 52.17.159.25452.17.159.2558,190
14252.17.160.0/1952.17.160.1 to 52.17.191.25452.17.191.2558,190
14352.17.192.0/1952.17.192.1 to 52.17.223.25452.17.223.2558,190
14452.17.224.0/1952.17.224.1 to 52.17.255.25452.17.255.2558,190
14552.18.0.0/1952.18.0.1 to 52.18.31.25452.18.31.2558,190
14652.18.32.0/1952.18.32.1 to 52.18.63.25452.18.63.2558,190
14752.18.64.0/1952.18.64.1 to 52.18.95.25452.18.95.2558,190
14852.18.96.0/1952.18.96.1 to 52.18.127.25452.18.127.2558,190
14952.18.128.0/1952.18.128.1 to 52.18.159.25452.18.159.2558,190
15052.18.160.0/1952.18.160.1 to 52.18.191.25452.18.191.2558,190
15152.18.192.0/1952.18.192.1 to 52.18.223.25452.18.223.2558,190
15252.18.224.0/1952.18.224.1 to 52.18.255.25452.18.255.2558,190
15352.19.0.0/1952.19.0.1 to 52.19.31.25452.19.31.2558,190
15452.19.32.0/1952.19.32.1 to 52.19.63.25452.19.63.2558,190
15552.19.64.0/1952.19.64.1 to 52.19.95.25452.19.95.2558,190
15652.19.96.0/1952.19.96.1 to 52.19.127.25452.19.127.2558,190
15752.19.128.0/1952.19.128.1 to 52.19.159.25452.19.159.2558,190
15852.19.160.0/1952.19.160.1 to 52.19.191.25452.19.191.2558,190
15952.19.192.0/1952.19.192.1 to 52.19.223.25452.19.223.2558,190
16052.19.224.0/1952.19.224.1 to 52.19.255.25452.19.255.2558,190
16152.20.0.0/1952.20.0.1 to 52.20.31.25452.20.31.2558,190
16252.20.32.0/1952.20.32.1 to 52.20.63.25452.20.63.2558,190
16352.20.64.0/1952.20.64.1 to 52.20.95.25452.20.95.2558,190
16452.20.96.0/1952.20.96.1 to 52.20.127.25452.20.127.2558,190
16552.20.128.0/1952.20.128.1 to 52.20.159.25452.20.159.2558,190
16652.20.160.0/1952.20.160.1 to 52.20.191.25452.20.191.2558,190
16752.20.192.0/1952.20.192.1 to 52.20.223.25452.20.223.2558,190
16852.20.224.0/1952.20.224.1 to 52.20.255.25452.20.255.2558,190
16952.21.0.0/1952.21.0.1 to 52.21.31.25452.21.31.2558,190
17052.21.32.0/1952.21.32.1 to 52.21.63.25452.21.63.2558,190
17152.21.64.0/1952.21.64.1 to 52.21.95.25452.21.95.2558,190
17252.21.96.0/1952.21.96.1 to 52.21.127.25452.21.127.2558,190
17352.21.128.0/1952.21.128.1 to 52.21.159.25452.21.159.2558,190
17452.21.160.0/1952.21.160.1 to 52.21.191.25452.21.191.2558,190
17552.21.192.0/1952.21.192.1 to 52.21.223.25452.21.223.2558,190
17652.21.224.0/1952.21.224.1 to 52.21.255.25452.21.255.2558,190
17752.22.0.0/1952.22.0.1 to 52.22.31.25452.22.31.2558,190
17852.22.32.0/1952.22.32.1 to 52.22.63.25452.22.63.2558,190
17952.22.64.0/1952.22.64.1 to 52.22.95.25452.22.95.2558,190
18052.22.96.0/1952.22.96.1 to 52.22.127.25452.22.127.2558,190
18152.22.128.0/1952.22.128.1 to 52.22.159.25452.22.159.2558,190
18252.22.160.0/1952.22.160.1 to 52.22.191.25452.22.191.2558,190
18352.22.192.0/1952.22.192.1 to 52.22.223.25452.22.223.2558,190
18452.22.224.0/1952.22.224.1 to 52.22.255.25452.22.255.2558,190
18552.23.0.0/1952.23.0.1 to 52.23.31.25452.23.31.2558,190
18652.23.32.0/1952.23.32.1 to 52.23.63.25452.23.63.2558,190
18752.23.64.0/1952.23.64.1 to 52.23.95.25452.23.95.2558,190
18852.23.96.0/1952.23.96.1 to 52.23.127.25452.23.127.2558,190
18952.23.128.0/1952.23.128.1 to 52.23.159.25452.23.159.2558,190
19052.23.160.0/1952.23.160.1 to 52.23.191.25452.23.191.2558,190
19152.23.192.0/1952.23.192.1 to 52.23.223.25452.23.223.2558,190
19252.23.224.0/1952.23.224.1 to 52.23.255.25452.23.255.2558,190
19352.24.0.0/1952.24.0.1 to 52.24.31.25452.24.31.2558,190
19452.24.32.0/1952.24.32.1 to 52.24.63.25452.24.63.2558,190
19552.24.64.0/1952.24.64.1 to 52.24.95.25452.24.95.2558,190
19652.24.96.0/1952.24.96.1 to 52.24.127.25452.24.127.2558,190
19752.24.128.0/1952.24.128.1 to 52.24.159.25452.24.159.2558,190
19852.24.160.0/1952.24.160.1 to 52.24.191.25452.24.191.2558,190
19952.24.192.0/1952.24.192.1 to 52.24.223.25452.24.223.2558,190
20052.24.224.0/1952.24.224.1 to 52.24.255.25452.24.255.2558,190
20152.25.0.0/1952.25.0.1 to 52.25.31.25452.25.31.2558,190
20252.25.32.0/1952.25.32.1 to 52.25.63.25452.25.63.2558,190
20352.25.64.0/1952.25.64.1 to 52.25.95.25452.25.95.2558,190
20452.25.96.0/1952.25.96.1 to 52.25.127.25452.25.127.2558,190
20552.25.128.0/1952.25.128.1 to 52.25.159.25452.25.159.2558,190
20652.25.160.0/1952.25.160.1 to 52.25.191.25452.25.191.2558,190
20752.25.192.0/1952.25.192.1 to 52.25.223.25452.25.223.2558,190
20852.25.224.0/1952.25.224.1 to 52.25.255.25452.25.255.2558,190
20952.26.0.0/1952.26.0.1 to 52.26.31.25452.26.31.2558,190
21052.26.32.0/1952.26.32.1 to 52.26.63.25452.26.63.2558,190
21152.26.64.0/1952.26.64.1 to 52.26.95.25452.26.95.2558,190
21252.26.96.0/1952.26.96.1 to 52.26.127.25452.26.127.2558,190
21352.26.128.0/1952.26.128.1 to 52.26.159.25452.26.159.2558,190
21452.26.160.0/1952.26.160.1 to 52.26.191.25452.26.191.2558,190
21552.26.192.0/1952.26.192.1 to 52.26.223.25452.26.223.2558,190
21652.26.224.0/1952.26.224.1 to 52.26.255.25452.26.255.2558,190
21752.27.0.0/1952.27.0.1 to 52.27.31.25452.27.31.2558,190
21852.27.32.0/1952.27.32.1 to 52.27.63.25452.27.63.2558,190
21952.27.64.0/1952.27.64.1 to 52.27.95.25452.27.95.2558,190
22052.27.96.0/1952.27.96.1 to 52.27.127.25452.27.127.2558,190
22152.27.128.0/1952.27.128.1 to 52.27.159.25452.27.159.2558,190
22252.27.160.0/1952.27.160.1 to 52.27.191.25452.27.191.2558,190
22352.27.192.0/1952.27.192.1 to 52.27.223.25452.27.223.2558,190
22452.27.224.0/1952.27.224.1 to 52.27.255.25452.27.255.2558,190
22552.28.0.0/1952.28.0.1 to 52.28.31.25452.28.31.2558,190
22652.28.32.0/1952.28.32.1 to 52.28.63.25452.28.63.2558,190
22752.28.64.0/1952.28.64.1 to 52.28.95.25452.28.95.2558,190
22852.28.96.0/1952.28.96.1 to 52.28.127.25452.28.127.2558,190
22952.28.128.0/1952.28.128.1 to 52.28.159.25452.28.159.2558,190
23052.28.160.0/1952.28.160.1 to 52.28.191.25452.28.191.2558,190
23152.28.192.0/1952.28.192.1 to 52.28.223.25452.28.223.2558,190
23252.28.224.0/1952.28.224.1 to 52.28.255.25452.28.255.2558,190
23352.29.0.0/1952.29.0.1 to 52.29.31.25452.29.31.2558,190
23452.29.32.0/1952.29.32.1 to 52.29.63.25452.29.63.2558,190
23552.29.64.0/1952.29.64.1 to 52.29.95.25452.29.95.2558,190
23652.29.96.0/1952.29.96.1 to 52.29.127.25452.29.127.2558,190
23752.29.128.0/1952.29.128.1 to 52.29.159.25452.29.159.2558,190
23852.29.160.0/1952.29.160.1 to 52.29.191.25452.29.191.2558,190
23952.29.192.0/1952.29.192.1 to 52.29.223.25452.29.223.2558,190
24052.29.224.0/1952.29.224.1 to 52.29.255.25452.29.255.2558,190
24152.30.0.0/1952.30.0.1 to 52.30.31.25452.30.31.2558,190
24252.30.32.0/1952.30.32.1 to 52.30.63.25452.30.63.2558,190
24352.30.64.0/1952.30.64.1 to 52.30.95.25452.30.95.2558,190
24452.30.96.0/1952.30.96.1 to 52.30.127.25452.30.127.2558,190
24552.30.128.0/1952.30.128.1 to 52.30.159.25452.30.159.2558,190
24652.30.160.0/1952.30.160.1 to 52.30.191.25452.30.191.2558,190
24752.30.192.0/1952.30.192.1 to 52.30.223.25452.30.223.2558,190
24852.30.224.0/1952.30.224.1 to 52.30.255.25452.30.255.2558,190
24952.31.0.0/1952.31.0.1 to 52.31.31.25452.31.31.2558,190
25052.31.32.0/1952.31.32.1 to 52.31.63.25452.31.63.2558,190
25152.31.64.0/1952.31.64.1 to 52.31.95.25452.31.95.2558,190
25252.31.96.0/1952.31.96.1 to 52.31.127.25452.31.127.2558,190
25352.31.128.0/1952.31.128.1 to 52.31.159.25452.31.159.2558,190
25452.31.160.0/1952.31.160.1 to 52.31.191.25452.31.191.2558,190
25552.31.192.0/1952.31.192.1 to 52.31.223.25452.31.223.2558,190
25652.31.224.0/1952.31.224.1 to 52.31.255.25452.31.255.2558,190

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.