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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/17
/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 1,024 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
152.0.0.0/1752.0.0.1 to 52.0.127.25452.0.127.25532,766
252.0.128.0/1752.0.128.1 to 52.0.255.25452.0.255.25532,766
352.1.0.0/1752.1.0.1 to 52.1.127.25452.1.127.25532,766
452.1.128.0/1752.1.128.1 to 52.1.255.25452.1.255.25532,766
552.2.0.0/1752.2.0.1 to 52.2.127.25452.2.127.25532,766
652.2.128.0/1752.2.128.1 to 52.2.255.25452.2.255.25532,766
752.3.0.0/1752.3.0.1 to 52.3.127.25452.3.127.25532,766
852.3.128.0/1752.3.128.1 to 52.3.255.25452.3.255.25532,766
952.4.0.0/1752.4.0.1 to 52.4.127.25452.4.127.25532,766
1052.4.128.0/1752.4.128.1 to 52.4.255.25452.4.255.25532,766
1152.5.0.0/1752.5.0.1 to 52.5.127.25452.5.127.25532,766
1252.5.128.0/1752.5.128.1 to 52.5.255.25452.5.255.25532,766
1352.6.0.0/1752.6.0.1 to 52.6.127.25452.6.127.25532,766
1452.6.128.0/1752.6.128.1 to 52.6.255.25452.6.255.25532,766
1552.7.0.0/1752.7.0.1 to 52.7.127.25452.7.127.25532,766
1652.7.128.0/1752.7.128.1 to 52.7.255.25452.7.255.25532,766
1752.8.0.0/1752.8.0.1 to 52.8.127.25452.8.127.25532,766
1852.8.128.0/1752.8.128.1 to 52.8.255.25452.8.255.25532,766
1952.9.0.0/1752.9.0.1 to 52.9.127.25452.9.127.25532,766
2052.9.128.0/1752.9.128.1 to 52.9.255.25452.9.255.25532,766
2152.10.0.0/1752.10.0.1 to 52.10.127.25452.10.127.25532,766
2252.10.128.0/1752.10.128.1 to 52.10.255.25452.10.255.25532,766
2352.11.0.0/1752.11.0.1 to 52.11.127.25452.11.127.25532,766
2452.11.128.0/1752.11.128.1 to 52.11.255.25452.11.255.25532,766
2552.12.0.0/1752.12.0.1 to 52.12.127.25452.12.127.25532,766
2652.12.128.0/1752.12.128.1 to 52.12.255.25452.12.255.25532,766
2752.13.0.0/1752.13.0.1 to 52.13.127.25452.13.127.25532,766
2852.13.128.0/1752.13.128.1 to 52.13.255.25452.13.255.25532,766
2952.14.0.0/1752.14.0.1 to 52.14.127.25452.14.127.25532,766
3052.14.128.0/1752.14.128.1 to 52.14.255.25452.14.255.25532,766
3152.15.0.0/1752.15.0.1 to 52.15.127.25452.15.127.25532,766
3252.15.128.0/1752.15.128.1 to 52.15.255.25452.15.255.25532,766
3352.16.0.0/1752.16.0.1 to 52.16.127.25452.16.127.25532,766
3452.16.128.0/1752.16.128.1 to 52.16.255.25452.16.255.25532,766
3552.17.0.0/1752.17.0.1 to 52.17.127.25452.17.127.25532,766
3652.17.128.0/1752.17.128.1 to 52.17.255.25452.17.255.25532,766
3752.18.0.0/1752.18.0.1 to 52.18.127.25452.18.127.25532,766
3852.18.128.0/1752.18.128.1 to 52.18.255.25452.18.255.25532,766
3952.19.0.0/1752.19.0.1 to 52.19.127.25452.19.127.25532,766
4052.19.128.0/1752.19.128.1 to 52.19.255.25452.19.255.25532,766
4152.20.0.0/1752.20.0.1 to 52.20.127.25452.20.127.25532,766
4252.20.128.0/1752.20.128.1 to 52.20.255.25452.20.255.25532,766
4352.21.0.0/1752.21.0.1 to 52.21.127.25452.21.127.25532,766
4452.21.128.0/1752.21.128.1 to 52.21.255.25452.21.255.25532,766
4552.22.0.0/1752.22.0.1 to 52.22.127.25452.22.127.25532,766
4652.22.128.0/1752.22.128.1 to 52.22.255.25452.22.255.25532,766
4752.23.0.0/1752.23.0.1 to 52.23.127.25452.23.127.25532,766
4852.23.128.0/1752.23.128.1 to 52.23.255.25452.23.255.25532,766
4952.24.0.0/1752.24.0.1 to 52.24.127.25452.24.127.25532,766
5052.24.128.0/1752.24.128.1 to 52.24.255.25452.24.255.25532,766
5152.25.0.0/1752.25.0.1 to 52.25.127.25452.25.127.25532,766
5252.25.128.0/1752.25.128.1 to 52.25.255.25452.25.255.25532,766
5352.26.0.0/1752.26.0.1 to 52.26.127.25452.26.127.25532,766
5452.26.128.0/1752.26.128.1 to 52.26.255.25452.26.255.25532,766
5552.27.0.0/1752.27.0.1 to 52.27.127.25452.27.127.25532,766
5652.27.128.0/1752.27.128.1 to 52.27.255.25452.27.255.25532,766
5752.28.0.0/1752.28.0.1 to 52.28.127.25452.28.127.25532,766
5852.28.128.0/1752.28.128.1 to 52.28.255.25452.28.255.25532,766
5952.29.0.0/1752.29.0.1 to 52.29.127.25452.29.127.25532,766
6052.29.128.0/1752.29.128.1 to 52.29.255.25452.29.255.25532,766
6152.30.0.0/1752.30.0.1 to 52.30.127.25452.30.127.25532,766
6252.30.128.0/1752.30.128.1 to 52.30.255.25452.30.255.25532,766
6352.31.0.0/1752.31.0.1 to 52.31.127.25452.31.127.25532,766
6452.31.128.0/1752.31.128.1 to 52.31.255.25452.31.255.25532,766
6552.32.0.0/1752.32.0.1 to 52.32.127.25452.32.127.25532,766
6652.32.128.0/1752.32.128.1 to 52.32.255.25452.32.255.25532,766
6752.33.0.0/1752.33.0.1 to 52.33.127.25452.33.127.25532,766
6852.33.128.0/1752.33.128.1 to 52.33.255.25452.33.255.25532,766
6952.34.0.0/1752.34.0.1 to 52.34.127.25452.34.127.25532,766
7052.34.128.0/1752.34.128.1 to 52.34.255.25452.34.255.25532,766
7152.35.0.0/1752.35.0.1 to 52.35.127.25452.35.127.25532,766
7252.35.128.0/1752.35.128.1 to 52.35.255.25452.35.255.25532,766
7352.36.0.0/1752.36.0.1 to 52.36.127.25452.36.127.25532,766
7452.36.128.0/1752.36.128.1 to 52.36.255.25452.36.255.25532,766
7552.37.0.0/1752.37.0.1 to 52.37.127.25452.37.127.25532,766
7652.37.128.0/1752.37.128.1 to 52.37.255.25452.37.255.25532,766
7752.38.0.0/1752.38.0.1 to 52.38.127.25452.38.127.25532,766
7852.38.128.0/1752.38.128.1 to 52.38.255.25452.38.255.25532,766
7952.39.0.0/1752.39.0.1 to 52.39.127.25452.39.127.25532,766
8052.39.128.0/1752.39.128.1 to 52.39.255.25452.39.255.25532,766
8152.40.0.0/1752.40.0.1 to 52.40.127.25452.40.127.25532,766
8252.40.128.0/1752.40.128.1 to 52.40.255.25452.40.255.25532,766
8352.41.0.0/1752.41.0.1 to 52.41.127.25452.41.127.25532,766
8452.41.128.0/1752.41.128.1 to 52.41.255.25452.41.255.25532,766
8552.42.0.0/1752.42.0.1 to 52.42.127.25452.42.127.25532,766
8652.42.128.0/1752.42.128.1 to 52.42.255.25452.42.255.25532,766
8752.43.0.0/1752.43.0.1 to 52.43.127.25452.43.127.25532,766
8852.43.128.0/1752.43.128.1 to 52.43.255.25452.43.255.25532,766
8952.44.0.0/1752.44.0.1 to 52.44.127.25452.44.127.25532,766
9052.44.128.0/1752.44.128.1 to 52.44.255.25452.44.255.25532,766
9152.45.0.0/1752.45.0.1 to 52.45.127.25452.45.127.25532,766
9252.45.128.0/1752.45.128.1 to 52.45.255.25452.45.255.25532,766
9352.46.0.0/1752.46.0.1 to 52.46.127.25452.46.127.25532,766
9452.46.128.0/1752.46.128.1 to 52.46.255.25452.46.255.25532,766
9552.47.0.0/1752.47.0.1 to 52.47.127.25452.47.127.25532,766
9652.47.128.0/1752.47.128.1 to 52.47.255.25452.47.255.25532,766
9752.48.0.0/1752.48.0.1 to 52.48.127.25452.48.127.25532,766
9852.48.128.0/1752.48.128.1 to 52.48.255.25452.48.255.25532,766
9952.49.0.0/1752.49.0.1 to 52.49.127.25452.49.127.25532,766
10052.49.128.0/1752.49.128.1 to 52.49.255.25452.49.255.25532,766
10152.50.0.0/1752.50.0.1 to 52.50.127.25452.50.127.25532,766
10252.50.128.0/1752.50.128.1 to 52.50.255.25452.50.255.25532,766
10352.51.0.0/1752.51.0.1 to 52.51.127.25452.51.127.25532,766
10452.51.128.0/1752.51.128.1 to 52.51.255.25452.51.255.25532,766
10552.52.0.0/1752.52.0.1 to 52.52.127.25452.52.127.25532,766
10652.52.128.0/1752.52.128.1 to 52.52.255.25452.52.255.25532,766
10752.53.0.0/1752.53.0.1 to 52.53.127.25452.53.127.25532,766
10852.53.128.0/1752.53.128.1 to 52.53.255.25452.53.255.25532,766
10952.54.0.0/1752.54.0.1 to 52.54.127.25452.54.127.25532,766
11052.54.128.0/1752.54.128.1 to 52.54.255.25452.54.255.25532,766
11152.55.0.0/1752.55.0.1 to 52.55.127.25452.55.127.25532,766
11252.55.128.0/1752.55.128.1 to 52.55.255.25452.55.255.25532,766
11352.56.0.0/1752.56.0.1 to 52.56.127.25452.56.127.25532,766
11452.56.128.0/1752.56.128.1 to 52.56.255.25452.56.255.25532,766
11552.57.0.0/1752.57.0.1 to 52.57.127.25452.57.127.25532,766
11652.57.128.0/1752.57.128.1 to 52.57.255.25452.57.255.25532,766
11752.58.0.0/1752.58.0.1 to 52.58.127.25452.58.127.25532,766
11852.58.128.0/1752.58.128.1 to 52.58.255.25452.58.255.25532,766
11952.59.0.0/1752.59.0.1 to 52.59.127.25452.59.127.25532,766
12052.59.128.0/1752.59.128.1 to 52.59.255.25452.59.255.25532,766
12152.60.0.0/1752.60.0.1 to 52.60.127.25452.60.127.25532,766
12252.60.128.0/1752.60.128.1 to 52.60.255.25452.60.255.25532,766
12352.61.0.0/1752.61.0.1 to 52.61.127.25452.61.127.25532,766
12452.61.128.0/1752.61.128.1 to 52.61.255.25452.61.255.25532,766
12552.62.0.0/1752.62.0.1 to 52.62.127.25452.62.127.25532,766
12652.62.128.0/1752.62.128.1 to 52.62.255.25452.62.255.25532,766
12752.63.0.0/1752.63.0.1 to 52.63.127.25452.63.127.25532,766
12852.63.128.0/1752.63.128.1 to 52.63.255.25452.63.255.25532,766
12952.64.0.0/1752.64.0.1 to 52.64.127.25452.64.127.25532,766
13052.64.128.0/1752.64.128.1 to 52.64.255.25452.64.255.25532,766
13152.65.0.0/1752.65.0.1 to 52.65.127.25452.65.127.25532,766
13252.65.128.0/1752.65.128.1 to 52.65.255.25452.65.255.25532,766
13352.66.0.0/1752.66.0.1 to 52.66.127.25452.66.127.25532,766
13452.66.128.0/1752.66.128.1 to 52.66.255.25452.66.255.25532,766
13552.67.0.0/1752.67.0.1 to 52.67.127.25452.67.127.25532,766
13652.67.128.0/1752.67.128.1 to 52.67.255.25452.67.255.25532,766
13752.68.0.0/1752.68.0.1 to 52.68.127.25452.68.127.25532,766
13852.68.128.0/1752.68.128.1 to 52.68.255.25452.68.255.25532,766
13952.69.0.0/1752.69.0.1 to 52.69.127.25452.69.127.25532,766
14052.69.128.0/1752.69.128.1 to 52.69.255.25452.69.255.25532,766
14152.70.0.0/1752.70.0.1 to 52.70.127.25452.70.127.25532,766
14252.70.128.0/1752.70.128.1 to 52.70.255.25452.70.255.25532,766
14352.71.0.0/1752.71.0.1 to 52.71.127.25452.71.127.25532,766
14452.71.128.0/1752.71.128.1 to 52.71.255.25452.71.255.25532,766
14552.72.0.0/1752.72.0.1 to 52.72.127.25452.72.127.25532,766
14652.72.128.0/1752.72.128.1 to 52.72.255.25452.72.255.25532,766
14752.73.0.0/1752.73.0.1 to 52.73.127.25452.73.127.25532,766
14852.73.128.0/1752.73.128.1 to 52.73.255.25452.73.255.25532,766
14952.74.0.0/1752.74.0.1 to 52.74.127.25452.74.127.25532,766
15052.74.128.0/1752.74.128.1 to 52.74.255.25452.74.255.25532,766
15152.75.0.0/1752.75.0.1 to 52.75.127.25452.75.127.25532,766
15252.75.128.0/1752.75.128.1 to 52.75.255.25452.75.255.25532,766
15352.76.0.0/1752.76.0.1 to 52.76.127.25452.76.127.25532,766
15452.76.128.0/1752.76.128.1 to 52.76.255.25452.76.255.25532,766
15552.77.0.0/1752.77.0.1 to 52.77.127.25452.77.127.25532,766
15652.77.128.0/1752.77.128.1 to 52.77.255.25452.77.255.25532,766
15752.78.0.0/1752.78.0.1 to 52.78.127.25452.78.127.25532,766
15852.78.128.0/1752.78.128.1 to 52.78.255.25452.78.255.25532,766
15952.79.0.0/1752.79.0.1 to 52.79.127.25452.79.127.25532,766
16052.79.128.0/1752.79.128.1 to 52.79.255.25452.79.255.25532,766
16152.80.0.0/1752.80.0.1 to 52.80.127.25452.80.127.25532,766
16252.80.128.0/1752.80.128.1 to 52.80.255.25452.80.255.25532,766
16352.81.0.0/1752.81.0.1 to 52.81.127.25452.81.127.25532,766
16452.81.128.0/1752.81.128.1 to 52.81.255.25452.81.255.25532,766
16552.82.0.0/1752.82.0.1 to 52.82.127.25452.82.127.25532,766
16652.82.128.0/1752.82.128.1 to 52.82.255.25452.82.255.25532,766
16752.83.0.0/1752.83.0.1 to 52.83.127.25452.83.127.25532,766
16852.83.128.0/1752.83.128.1 to 52.83.255.25452.83.255.25532,766
16952.84.0.0/1752.84.0.1 to 52.84.127.25452.84.127.25532,766
17052.84.128.0/1752.84.128.1 to 52.84.255.25452.84.255.25532,766
17152.85.0.0/1752.85.0.1 to 52.85.127.25452.85.127.25532,766
17252.85.128.0/1752.85.128.1 to 52.85.255.25452.85.255.25532,766
17352.86.0.0/1752.86.0.1 to 52.86.127.25452.86.127.25532,766
17452.86.128.0/1752.86.128.1 to 52.86.255.25452.86.255.25532,766
17552.87.0.0/1752.87.0.1 to 52.87.127.25452.87.127.25532,766
17652.87.128.0/1752.87.128.1 to 52.87.255.25452.87.255.25532,766
17752.88.0.0/1752.88.0.1 to 52.88.127.25452.88.127.25532,766
17852.88.128.0/1752.88.128.1 to 52.88.255.25452.88.255.25532,766
17952.89.0.0/1752.89.0.1 to 52.89.127.25452.89.127.25532,766
18052.89.128.0/1752.89.128.1 to 52.89.255.25452.89.255.25532,766
18152.90.0.0/1752.90.0.1 to 52.90.127.25452.90.127.25532,766
18252.90.128.0/1752.90.128.1 to 52.90.255.25452.90.255.25532,766
18352.91.0.0/1752.91.0.1 to 52.91.127.25452.91.127.25532,766
18452.91.128.0/1752.91.128.1 to 52.91.255.25452.91.255.25532,766
18552.92.0.0/1752.92.0.1 to 52.92.127.25452.92.127.25532,766
18652.92.128.0/1752.92.128.1 to 52.92.255.25452.92.255.25532,766
18752.93.0.0/1752.93.0.1 to 52.93.127.25452.93.127.25532,766
18852.93.128.0/1752.93.128.1 to 52.93.255.25452.93.255.25532,766
18952.94.0.0/1752.94.0.1 to 52.94.127.25452.94.127.25532,766
19052.94.128.0/1752.94.128.1 to 52.94.255.25452.94.255.25532,766
19152.95.0.0/1752.95.0.1 to 52.95.127.25452.95.127.25532,766
19252.95.128.0/1752.95.128.1 to 52.95.255.25452.95.255.25532,766
19352.96.0.0/1752.96.0.1 to 52.96.127.25452.96.127.25532,766
19452.96.128.0/1752.96.128.1 to 52.96.255.25452.96.255.25532,766
19552.97.0.0/1752.97.0.1 to 52.97.127.25452.97.127.25532,766
19652.97.128.0/1752.97.128.1 to 52.97.255.25452.97.255.25532,766
19752.98.0.0/1752.98.0.1 to 52.98.127.25452.98.127.25532,766
19852.98.128.0/1752.98.128.1 to 52.98.255.25452.98.255.25532,766
19952.99.0.0/1752.99.0.1 to 52.99.127.25452.99.127.25532,766
20052.99.128.0/1752.99.128.1 to 52.99.255.25452.99.255.25532,766
20152.100.0.0/1752.100.0.1 to 52.100.127.25452.100.127.25532,766
20252.100.128.0/1752.100.128.1 to 52.100.255.25452.100.255.25532,766
20352.101.0.0/1752.101.0.1 to 52.101.127.25452.101.127.25532,766
20452.101.128.0/1752.101.128.1 to 52.101.255.25452.101.255.25532,766
20552.102.0.0/1752.102.0.1 to 52.102.127.25452.102.127.25532,766
20652.102.128.0/1752.102.128.1 to 52.102.255.25452.102.255.25532,766
20752.103.0.0/1752.103.0.1 to 52.103.127.25452.103.127.25532,766
20852.103.128.0/1752.103.128.1 to 52.103.255.25452.103.255.25532,766
20952.104.0.0/1752.104.0.1 to 52.104.127.25452.104.127.25532,766
21052.104.128.0/1752.104.128.1 to 52.104.255.25452.104.255.25532,766
21152.105.0.0/1752.105.0.1 to 52.105.127.25452.105.127.25532,766
21252.105.128.0/1752.105.128.1 to 52.105.255.25452.105.255.25532,766
21352.106.0.0/1752.106.0.1 to 52.106.127.25452.106.127.25532,766
21452.106.128.0/1752.106.128.1 to 52.106.255.25452.106.255.25532,766
21552.107.0.0/1752.107.0.1 to 52.107.127.25452.107.127.25532,766
21652.107.128.0/1752.107.128.1 to 52.107.255.25452.107.255.25532,766
21752.108.0.0/1752.108.0.1 to 52.108.127.25452.108.127.25532,766
21852.108.128.0/1752.108.128.1 to 52.108.255.25452.108.255.25532,766
21952.109.0.0/1752.109.0.1 to 52.109.127.25452.109.127.25532,766
22052.109.128.0/1752.109.128.1 to 52.109.255.25452.109.255.25532,766
22152.110.0.0/1752.110.0.1 to 52.110.127.25452.110.127.25532,766
22252.110.128.0/1752.110.128.1 to 52.110.255.25452.110.255.25532,766
22352.111.0.0/1752.111.0.1 to 52.111.127.25452.111.127.25532,766
22452.111.128.0/1752.111.128.1 to 52.111.255.25452.111.255.25532,766
22552.112.0.0/1752.112.0.1 to 52.112.127.25452.112.127.25532,766
22652.112.128.0/1752.112.128.1 to 52.112.255.25452.112.255.25532,766
22752.113.0.0/1752.113.0.1 to 52.113.127.25452.113.127.25532,766
22852.113.128.0/1752.113.128.1 to 52.113.255.25452.113.255.25532,766
22952.114.0.0/1752.114.0.1 to 52.114.127.25452.114.127.25532,766
23052.114.128.0/1752.114.128.1 to 52.114.255.25452.114.255.25532,766
23152.115.0.0/1752.115.0.1 to 52.115.127.25452.115.127.25532,766
23252.115.128.0/1752.115.128.1 to 52.115.255.25452.115.255.25532,766
23352.116.0.0/1752.116.0.1 to 52.116.127.25452.116.127.25532,766
23452.116.128.0/1752.116.128.1 to 52.116.255.25452.116.255.25532,766
23552.117.0.0/1752.117.0.1 to 52.117.127.25452.117.127.25532,766
23652.117.128.0/1752.117.128.1 to 52.117.255.25452.117.255.25532,766
23752.118.0.0/1752.118.0.1 to 52.118.127.25452.118.127.25532,766
23852.118.128.0/1752.118.128.1 to 52.118.255.25452.118.255.25532,766
23952.119.0.0/1752.119.0.1 to 52.119.127.25452.119.127.25532,766
24052.119.128.0/1752.119.128.1 to 52.119.255.25452.119.255.25532,766
24152.120.0.0/1752.120.0.1 to 52.120.127.25452.120.127.25532,766
24252.120.128.0/1752.120.128.1 to 52.120.255.25452.120.255.25532,766
24352.121.0.0/1752.121.0.1 to 52.121.127.25452.121.127.25532,766
24452.121.128.0/1752.121.128.1 to 52.121.255.25452.121.255.25532,766
24552.122.0.0/1752.122.0.1 to 52.122.127.25452.122.127.25532,766
24652.122.128.0/1752.122.128.1 to 52.122.255.25452.122.255.25532,766
24752.123.0.0/1752.123.0.1 to 52.123.127.25452.123.127.25532,766
24852.123.128.0/1752.123.128.1 to 52.123.255.25452.123.255.25532,766
24952.124.0.0/1752.124.0.1 to 52.124.127.25452.124.127.25532,766
25052.124.128.0/1752.124.128.1 to 52.124.255.25452.124.255.25532,766
25152.125.0.0/1752.125.0.1 to 52.125.127.25452.125.127.25532,766
25252.125.128.0/1752.125.128.1 to 52.125.255.25452.125.255.25532,766
25352.126.0.0/1752.126.0.1 to 52.126.127.25452.126.127.25532,766
25452.126.128.0/1752.126.128.1 to 52.126.255.25452.126.255.25532,766
25552.127.0.0/1752.127.0.1 to 52.127.127.25452.127.127.25532,766
25652.127.128.0/1752.127.128.1 to 52.127.255.25452.127.255.25532,766

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.