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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/18
/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 2,048 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
152.0.0.0/1852.0.0.1 to 52.0.63.25452.0.63.25516,382
252.0.64.0/1852.0.64.1 to 52.0.127.25452.0.127.25516,382
352.0.128.0/1852.0.128.1 to 52.0.191.25452.0.191.25516,382
452.0.192.0/1852.0.192.1 to 52.0.255.25452.0.255.25516,382
552.1.0.0/1852.1.0.1 to 52.1.63.25452.1.63.25516,382
652.1.64.0/1852.1.64.1 to 52.1.127.25452.1.127.25516,382
752.1.128.0/1852.1.128.1 to 52.1.191.25452.1.191.25516,382
852.1.192.0/1852.1.192.1 to 52.1.255.25452.1.255.25516,382
952.2.0.0/1852.2.0.1 to 52.2.63.25452.2.63.25516,382
1052.2.64.0/1852.2.64.1 to 52.2.127.25452.2.127.25516,382
1152.2.128.0/1852.2.128.1 to 52.2.191.25452.2.191.25516,382
1252.2.192.0/1852.2.192.1 to 52.2.255.25452.2.255.25516,382
1352.3.0.0/1852.3.0.1 to 52.3.63.25452.3.63.25516,382
1452.3.64.0/1852.3.64.1 to 52.3.127.25452.3.127.25516,382
1552.3.128.0/1852.3.128.1 to 52.3.191.25452.3.191.25516,382
1652.3.192.0/1852.3.192.1 to 52.3.255.25452.3.255.25516,382
1752.4.0.0/1852.4.0.1 to 52.4.63.25452.4.63.25516,382
1852.4.64.0/1852.4.64.1 to 52.4.127.25452.4.127.25516,382
1952.4.128.0/1852.4.128.1 to 52.4.191.25452.4.191.25516,382
2052.4.192.0/1852.4.192.1 to 52.4.255.25452.4.255.25516,382
2152.5.0.0/1852.5.0.1 to 52.5.63.25452.5.63.25516,382
2252.5.64.0/1852.5.64.1 to 52.5.127.25452.5.127.25516,382
2352.5.128.0/1852.5.128.1 to 52.5.191.25452.5.191.25516,382
2452.5.192.0/1852.5.192.1 to 52.5.255.25452.5.255.25516,382
2552.6.0.0/1852.6.0.1 to 52.6.63.25452.6.63.25516,382
2652.6.64.0/1852.6.64.1 to 52.6.127.25452.6.127.25516,382
2752.6.128.0/1852.6.128.1 to 52.6.191.25452.6.191.25516,382
2852.6.192.0/1852.6.192.1 to 52.6.255.25452.6.255.25516,382
2952.7.0.0/1852.7.0.1 to 52.7.63.25452.7.63.25516,382
3052.7.64.0/1852.7.64.1 to 52.7.127.25452.7.127.25516,382
3152.7.128.0/1852.7.128.1 to 52.7.191.25452.7.191.25516,382
3252.7.192.0/1852.7.192.1 to 52.7.255.25452.7.255.25516,382
3352.8.0.0/1852.8.0.1 to 52.8.63.25452.8.63.25516,382
3452.8.64.0/1852.8.64.1 to 52.8.127.25452.8.127.25516,382
3552.8.128.0/1852.8.128.1 to 52.8.191.25452.8.191.25516,382
3652.8.192.0/1852.8.192.1 to 52.8.255.25452.8.255.25516,382
3752.9.0.0/1852.9.0.1 to 52.9.63.25452.9.63.25516,382
3852.9.64.0/1852.9.64.1 to 52.9.127.25452.9.127.25516,382
3952.9.128.0/1852.9.128.1 to 52.9.191.25452.9.191.25516,382
4052.9.192.0/1852.9.192.1 to 52.9.255.25452.9.255.25516,382
4152.10.0.0/1852.10.0.1 to 52.10.63.25452.10.63.25516,382
4252.10.64.0/1852.10.64.1 to 52.10.127.25452.10.127.25516,382
4352.10.128.0/1852.10.128.1 to 52.10.191.25452.10.191.25516,382
4452.10.192.0/1852.10.192.1 to 52.10.255.25452.10.255.25516,382
4552.11.0.0/1852.11.0.1 to 52.11.63.25452.11.63.25516,382
4652.11.64.0/1852.11.64.1 to 52.11.127.25452.11.127.25516,382
4752.11.128.0/1852.11.128.1 to 52.11.191.25452.11.191.25516,382
4852.11.192.0/1852.11.192.1 to 52.11.255.25452.11.255.25516,382
4952.12.0.0/1852.12.0.1 to 52.12.63.25452.12.63.25516,382
5052.12.64.0/1852.12.64.1 to 52.12.127.25452.12.127.25516,382
5152.12.128.0/1852.12.128.1 to 52.12.191.25452.12.191.25516,382
5252.12.192.0/1852.12.192.1 to 52.12.255.25452.12.255.25516,382
5352.13.0.0/1852.13.0.1 to 52.13.63.25452.13.63.25516,382
5452.13.64.0/1852.13.64.1 to 52.13.127.25452.13.127.25516,382
5552.13.128.0/1852.13.128.1 to 52.13.191.25452.13.191.25516,382
5652.13.192.0/1852.13.192.1 to 52.13.255.25452.13.255.25516,382
5752.14.0.0/1852.14.0.1 to 52.14.63.25452.14.63.25516,382
5852.14.64.0/1852.14.64.1 to 52.14.127.25452.14.127.25516,382
5952.14.128.0/1852.14.128.1 to 52.14.191.25452.14.191.25516,382
6052.14.192.0/1852.14.192.1 to 52.14.255.25452.14.255.25516,382
6152.15.0.0/1852.15.0.1 to 52.15.63.25452.15.63.25516,382
6252.15.64.0/1852.15.64.1 to 52.15.127.25452.15.127.25516,382
6352.15.128.0/1852.15.128.1 to 52.15.191.25452.15.191.25516,382
6452.15.192.0/1852.15.192.1 to 52.15.255.25452.15.255.25516,382
6552.16.0.0/1852.16.0.1 to 52.16.63.25452.16.63.25516,382
6652.16.64.0/1852.16.64.1 to 52.16.127.25452.16.127.25516,382
6752.16.128.0/1852.16.128.1 to 52.16.191.25452.16.191.25516,382
6852.16.192.0/1852.16.192.1 to 52.16.255.25452.16.255.25516,382
6952.17.0.0/1852.17.0.1 to 52.17.63.25452.17.63.25516,382
7052.17.64.0/1852.17.64.1 to 52.17.127.25452.17.127.25516,382
7152.17.128.0/1852.17.128.1 to 52.17.191.25452.17.191.25516,382
7252.17.192.0/1852.17.192.1 to 52.17.255.25452.17.255.25516,382
7352.18.0.0/1852.18.0.1 to 52.18.63.25452.18.63.25516,382
7452.18.64.0/1852.18.64.1 to 52.18.127.25452.18.127.25516,382
7552.18.128.0/1852.18.128.1 to 52.18.191.25452.18.191.25516,382
7652.18.192.0/1852.18.192.1 to 52.18.255.25452.18.255.25516,382
7752.19.0.0/1852.19.0.1 to 52.19.63.25452.19.63.25516,382
7852.19.64.0/1852.19.64.1 to 52.19.127.25452.19.127.25516,382
7952.19.128.0/1852.19.128.1 to 52.19.191.25452.19.191.25516,382
8052.19.192.0/1852.19.192.1 to 52.19.255.25452.19.255.25516,382
8152.20.0.0/1852.20.0.1 to 52.20.63.25452.20.63.25516,382
8252.20.64.0/1852.20.64.1 to 52.20.127.25452.20.127.25516,382
8352.20.128.0/1852.20.128.1 to 52.20.191.25452.20.191.25516,382
8452.20.192.0/1852.20.192.1 to 52.20.255.25452.20.255.25516,382
8552.21.0.0/1852.21.0.1 to 52.21.63.25452.21.63.25516,382
8652.21.64.0/1852.21.64.1 to 52.21.127.25452.21.127.25516,382
8752.21.128.0/1852.21.128.1 to 52.21.191.25452.21.191.25516,382
8852.21.192.0/1852.21.192.1 to 52.21.255.25452.21.255.25516,382
8952.22.0.0/1852.22.0.1 to 52.22.63.25452.22.63.25516,382
9052.22.64.0/1852.22.64.1 to 52.22.127.25452.22.127.25516,382
9152.22.128.0/1852.22.128.1 to 52.22.191.25452.22.191.25516,382
9252.22.192.0/1852.22.192.1 to 52.22.255.25452.22.255.25516,382
9352.23.0.0/1852.23.0.1 to 52.23.63.25452.23.63.25516,382
9452.23.64.0/1852.23.64.1 to 52.23.127.25452.23.127.25516,382
9552.23.128.0/1852.23.128.1 to 52.23.191.25452.23.191.25516,382
9652.23.192.0/1852.23.192.1 to 52.23.255.25452.23.255.25516,382
9752.24.0.0/1852.24.0.1 to 52.24.63.25452.24.63.25516,382
9852.24.64.0/1852.24.64.1 to 52.24.127.25452.24.127.25516,382
9952.24.128.0/1852.24.128.1 to 52.24.191.25452.24.191.25516,382
10052.24.192.0/1852.24.192.1 to 52.24.255.25452.24.255.25516,382
10152.25.0.0/1852.25.0.1 to 52.25.63.25452.25.63.25516,382
10252.25.64.0/1852.25.64.1 to 52.25.127.25452.25.127.25516,382
10352.25.128.0/1852.25.128.1 to 52.25.191.25452.25.191.25516,382
10452.25.192.0/1852.25.192.1 to 52.25.255.25452.25.255.25516,382
10552.26.0.0/1852.26.0.1 to 52.26.63.25452.26.63.25516,382
10652.26.64.0/1852.26.64.1 to 52.26.127.25452.26.127.25516,382
10752.26.128.0/1852.26.128.1 to 52.26.191.25452.26.191.25516,382
10852.26.192.0/1852.26.192.1 to 52.26.255.25452.26.255.25516,382
10952.27.0.0/1852.27.0.1 to 52.27.63.25452.27.63.25516,382
11052.27.64.0/1852.27.64.1 to 52.27.127.25452.27.127.25516,382
11152.27.128.0/1852.27.128.1 to 52.27.191.25452.27.191.25516,382
11252.27.192.0/1852.27.192.1 to 52.27.255.25452.27.255.25516,382
11352.28.0.0/1852.28.0.1 to 52.28.63.25452.28.63.25516,382
11452.28.64.0/1852.28.64.1 to 52.28.127.25452.28.127.25516,382
11552.28.128.0/1852.28.128.1 to 52.28.191.25452.28.191.25516,382
11652.28.192.0/1852.28.192.1 to 52.28.255.25452.28.255.25516,382
11752.29.0.0/1852.29.0.1 to 52.29.63.25452.29.63.25516,382
11852.29.64.0/1852.29.64.1 to 52.29.127.25452.29.127.25516,382
11952.29.128.0/1852.29.128.1 to 52.29.191.25452.29.191.25516,382
12052.29.192.0/1852.29.192.1 to 52.29.255.25452.29.255.25516,382
12152.30.0.0/1852.30.0.1 to 52.30.63.25452.30.63.25516,382
12252.30.64.0/1852.30.64.1 to 52.30.127.25452.30.127.25516,382
12352.30.128.0/1852.30.128.1 to 52.30.191.25452.30.191.25516,382
12452.30.192.0/1852.30.192.1 to 52.30.255.25452.30.255.25516,382
12552.31.0.0/1852.31.0.1 to 52.31.63.25452.31.63.25516,382
12652.31.64.0/1852.31.64.1 to 52.31.127.25452.31.127.25516,382
12752.31.128.0/1852.31.128.1 to 52.31.191.25452.31.191.25516,382
12852.31.192.0/1852.31.192.1 to 52.31.255.25452.31.255.25516,382
12952.32.0.0/1852.32.0.1 to 52.32.63.25452.32.63.25516,382
13052.32.64.0/1852.32.64.1 to 52.32.127.25452.32.127.25516,382
13152.32.128.0/1852.32.128.1 to 52.32.191.25452.32.191.25516,382
13252.32.192.0/1852.32.192.1 to 52.32.255.25452.32.255.25516,382
13352.33.0.0/1852.33.0.1 to 52.33.63.25452.33.63.25516,382
13452.33.64.0/1852.33.64.1 to 52.33.127.25452.33.127.25516,382
13552.33.128.0/1852.33.128.1 to 52.33.191.25452.33.191.25516,382
13652.33.192.0/1852.33.192.1 to 52.33.255.25452.33.255.25516,382
13752.34.0.0/1852.34.0.1 to 52.34.63.25452.34.63.25516,382
13852.34.64.0/1852.34.64.1 to 52.34.127.25452.34.127.25516,382
13952.34.128.0/1852.34.128.1 to 52.34.191.25452.34.191.25516,382
14052.34.192.0/1852.34.192.1 to 52.34.255.25452.34.255.25516,382
14152.35.0.0/1852.35.0.1 to 52.35.63.25452.35.63.25516,382
14252.35.64.0/1852.35.64.1 to 52.35.127.25452.35.127.25516,382
14352.35.128.0/1852.35.128.1 to 52.35.191.25452.35.191.25516,382
14452.35.192.0/1852.35.192.1 to 52.35.255.25452.35.255.25516,382
14552.36.0.0/1852.36.0.1 to 52.36.63.25452.36.63.25516,382
14652.36.64.0/1852.36.64.1 to 52.36.127.25452.36.127.25516,382
14752.36.128.0/1852.36.128.1 to 52.36.191.25452.36.191.25516,382
14852.36.192.0/1852.36.192.1 to 52.36.255.25452.36.255.25516,382
14952.37.0.0/1852.37.0.1 to 52.37.63.25452.37.63.25516,382
15052.37.64.0/1852.37.64.1 to 52.37.127.25452.37.127.25516,382
15152.37.128.0/1852.37.128.1 to 52.37.191.25452.37.191.25516,382
15252.37.192.0/1852.37.192.1 to 52.37.255.25452.37.255.25516,382
15352.38.0.0/1852.38.0.1 to 52.38.63.25452.38.63.25516,382
15452.38.64.0/1852.38.64.1 to 52.38.127.25452.38.127.25516,382
15552.38.128.0/1852.38.128.1 to 52.38.191.25452.38.191.25516,382
15652.38.192.0/1852.38.192.1 to 52.38.255.25452.38.255.25516,382
15752.39.0.0/1852.39.0.1 to 52.39.63.25452.39.63.25516,382
15852.39.64.0/1852.39.64.1 to 52.39.127.25452.39.127.25516,382
15952.39.128.0/1852.39.128.1 to 52.39.191.25452.39.191.25516,382
16052.39.192.0/1852.39.192.1 to 52.39.255.25452.39.255.25516,382
16152.40.0.0/1852.40.0.1 to 52.40.63.25452.40.63.25516,382
16252.40.64.0/1852.40.64.1 to 52.40.127.25452.40.127.25516,382
16352.40.128.0/1852.40.128.1 to 52.40.191.25452.40.191.25516,382
16452.40.192.0/1852.40.192.1 to 52.40.255.25452.40.255.25516,382
16552.41.0.0/1852.41.0.1 to 52.41.63.25452.41.63.25516,382
16652.41.64.0/1852.41.64.1 to 52.41.127.25452.41.127.25516,382
16752.41.128.0/1852.41.128.1 to 52.41.191.25452.41.191.25516,382
16852.41.192.0/1852.41.192.1 to 52.41.255.25452.41.255.25516,382
16952.42.0.0/1852.42.0.1 to 52.42.63.25452.42.63.25516,382
17052.42.64.0/1852.42.64.1 to 52.42.127.25452.42.127.25516,382
17152.42.128.0/1852.42.128.1 to 52.42.191.25452.42.191.25516,382
17252.42.192.0/1852.42.192.1 to 52.42.255.25452.42.255.25516,382
17352.43.0.0/1852.43.0.1 to 52.43.63.25452.43.63.25516,382
17452.43.64.0/1852.43.64.1 to 52.43.127.25452.43.127.25516,382
17552.43.128.0/1852.43.128.1 to 52.43.191.25452.43.191.25516,382
17652.43.192.0/1852.43.192.1 to 52.43.255.25452.43.255.25516,382
17752.44.0.0/1852.44.0.1 to 52.44.63.25452.44.63.25516,382
17852.44.64.0/1852.44.64.1 to 52.44.127.25452.44.127.25516,382
17952.44.128.0/1852.44.128.1 to 52.44.191.25452.44.191.25516,382
18052.44.192.0/1852.44.192.1 to 52.44.255.25452.44.255.25516,382
18152.45.0.0/1852.45.0.1 to 52.45.63.25452.45.63.25516,382
18252.45.64.0/1852.45.64.1 to 52.45.127.25452.45.127.25516,382
18352.45.128.0/1852.45.128.1 to 52.45.191.25452.45.191.25516,382
18452.45.192.0/1852.45.192.1 to 52.45.255.25452.45.255.25516,382
18552.46.0.0/1852.46.0.1 to 52.46.63.25452.46.63.25516,382
18652.46.64.0/1852.46.64.1 to 52.46.127.25452.46.127.25516,382
18752.46.128.0/1852.46.128.1 to 52.46.191.25452.46.191.25516,382
18852.46.192.0/1852.46.192.1 to 52.46.255.25452.46.255.25516,382
18952.47.0.0/1852.47.0.1 to 52.47.63.25452.47.63.25516,382
19052.47.64.0/1852.47.64.1 to 52.47.127.25452.47.127.25516,382
19152.47.128.0/1852.47.128.1 to 52.47.191.25452.47.191.25516,382
19252.47.192.0/1852.47.192.1 to 52.47.255.25452.47.255.25516,382
19352.48.0.0/1852.48.0.1 to 52.48.63.25452.48.63.25516,382
19452.48.64.0/1852.48.64.1 to 52.48.127.25452.48.127.25516,382
19552.48.128.0/1852.48.128.1 to 52.48.191.25452.48.191.25516,382
19652.48.192.0/1852.48.192.1 to 52.48.255.25452.48.255.25516,382
19752.49.0.0/1852.49.0.1 to 52.49.63.25452.49.63.25516,382
19852.49.64.0/1852.49.64.1 to 52.49.127.25452.49.127.25516,382
19952.49.128.0/1852.49.128.1 to 52.49.191.25452.49.191.25516,382
20052.49.192.0/1852.49.192.1 to 52.49.255.25452.49.255.25516,382
20152.50.0.0/1852.50.0.1 to 52.50.63.25452.50.63.25516,382
20252.50.64.0/1852.50.64.1 to 52.50.127.25452.50.127.25516,382
20352.50.128.0/1852.50.128.1 to 52.50.191.25452.50.191.25516,382
20452.50.192.0/1852.50.192.1 to 52.50.255.25452.50.255.25516,382
20552.51.0.0/1852.51.0.1 to 52.51.63.25452.51.63.25516,382
20652.51.64.0/1852.51.64.1 to 52.51.127.25452.51.127.25516,382
20752.51.128.0/1852.51.128.1 to 52.51.191.25452.51.191.25516,382
20852.51.192.0/1852.51.192.1 to 52.51.255.25452.51.255.25516,382
20952.52.0.0/1852.52.0.1 to 52.52.63.25452.52.63.25516,382
21052.52.64.0/1852.52.64.1 to 52.52.127.25452.52.127.25516,382
21152.52.128.0/1852.52.128.1 to 52.52.191.25452.52.191.25516,382
21252.52.192.0/1852.52.192.1 to 52.52.255.25452.52.255.25516,382
21352.53.0.0/1852.53.0.1 to 52.53.63.25452.53.63.25516,382
21452.53.64.0/1852.53.64.1 to 52.53.127.25452.53.127.25516,382
21552.53.128.0/1852.53.128.1 to 52.53.191.25452.53.191.25516,382
21652.53.192.0/1852.53.192.1 to 52.53.255.25452.53.255.25516,382
21752.54.0.0/1852.54.0.1 to 52.54.63.25452.54.63.25516,382
21852.54.64.0/1852.54.64.1 to 52.54.127.25452.54.127.25516,382
21952.54.128.0/1852.54.128.1 to 52.54.191.25452.54.191.25516,382
22052.54.192.0/1852.54.192.1 to 52.54.255.25452.54.255.25516,382
22152.55.0.0/1852.55.0.1 to 52.55.63.25452.55.63.25516,382
22252.55.64.0/1852.55.64.1 to 52.55.127.25452.55.127.25516,382
22352.55.128.0/1852.55.128.1 to 52.55.191.25452.55.191.25516,382
22452.55.192.0/1852.55.192.1 to 52.55.255.25452.55.255.25516,382
22552.56.0.0/1852.56.0.1 to 52.56.63.25452.56.63.25516,382
22652.56.64.0/1852.56.64.1 to 52.56.127.25452.56.127.25516,382
22752.56.128.0/1852.56.128.1 to 52.56.191.25452.56.191.25516,382
22852.56.192.0/1852.56.192.1 to 52.56.255.25452.56.255.25516,382
22952.57.0.0/1852.57.0.1 to 52.57.63.25452.57.63.25516,382
23052.57.64.0/1852.57.64.1 to 52.57.127.25452.57.127.25516,382
23152.57.128.0/1852.57.128.1 to 52.57.191.25452.57.191.25516,382
23252.57.192.0/1852.57.192.1 to 52.57.255.25452.57.255.25516,382
23352.58.0.0/1852.58.0.1 to 52.58.63.25452.58.63.25516,382
23452.58.64.0/1852.58.64.1 to 52.58.127.25452.58.127.25516,382
23552.58.128.0/1852.58.128.1 to 52.58.191.25452.58.191.25516,382
23652.58.192.0/1852.58.192.1 to 52.58.255.25452.58.255.25516,382
23752.59.0.0/1852.59.0.1 to 52.59.63.25452.59.63.25516,382
23852.59.64.0/1852.59.64.1 to 52.59.127.25452.59.127.25516,382
23952.59.128.0/1852.59.128.1 to 52.59.191.25452.59.191.25516,382
24052.59.192.0/1852.59.192.1 to 52.59.255.25452.59.255.25516,382
24152.60.0.0/1852.60.0.1 to 52.60.63.25452.60.63.25516,382
24252.60.64.0/1852.60.64.1 to 52.60.127.25452.60.127.25516,382
24352.60.128.0/1852.60.128.1 to 52.60.191.25452.60.191.25516,382
24452.60.192.0/1852.60.192.1 to 52.60.255.25452.60.255.25516,382
24552.61.0.0/1852.61.0.1 to 52.61.63.25452.61.63.25516,382
24652.61.64.0/1852.61.64.1 to 52.61.127.25452.61.127.25516,382
24752.61.128.0/1852.61.128.1 to 52.61.191.25452.61.191.25516,382
24852.61.192.0/1852.61.192.1 to 52.61.255.25452.61.255.25516,382
24952.62.0.0/1852.62.0.1 to 52.62.63.25452.62.63.25516,382
25052.62.64.0/1852.62.64.1 to 52.62.127.25452.62.127.25516,382
25152.62.128.0/1852.62.128.1 to 52.62.191.25452.62.191.25516,382
25252.62.192.0/1852.62.192.1 to 52.62.255.25452.62.255.25516,382
25352.63.0.0/1852.63.0.1 to 52.63.63.25452.63.63.25516,382
25452.63.64.0/1852.63.64.1 to 52.63.127.25452.63.127.25516,382
25552.63.128.0/1852.63.128.1 to 52.63.191.25452.63.191.25516,382
25652.63.192.0/1852.63.192.1 to 52.63.255.25452.63.255.25516,382

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.