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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.

Network11.44.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
11.44.0.0
Broadcast address
11.45.255.255
First usable
11.44.0.1
Last usable
11.45.255.254
Usable hosts
131,070 (131,072 less the network and broadcast addresses)
Subnet mask
255.254.0.0
Wildcard mask
0.1.255.255 (Cisco ACLs, OSPF)
Prefix length
/15
Type
Public public
Old class
A (default /8)
As numbers
Hex 0B2C0000 · Integer 187432960 to 187564031
Reverse DNS zones
44.11.in-addr.arpa
45.11.in-addr.arpa
/15 is not on a 8-bit boundary, so it takes 2 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001011.00101100.00000000.0000000011.44.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network00001011.00101100.00000000.0000000011.44.0.0
Broadcast00001011.00101101.11111111.1111111111.45.255.255
Split into smaller subnets/26
/16 (2)/17 (4)/18 (8)/19 (16)/20 (32)/21 (64)/22 (128)/23 (256)/24 (512)/25 (1,024)/26 (2,048)/27 (4,096)

11.44.0.0/15 makes 2,048 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
111.44.0.0/2611.44.0.1 to 11.44.0.6211.44.0.6362
211.44.0.64/2611.44.0.65 to 11.44.0.12611.44.0.12762
311.44.0.128/2611.44.0.129 to 11.44.0.19011.44.0.19162
411.44.0.192/2611.44.0.193 to 11.44.0.25411.44.0.25562
511.44.1.0/2611.44.1.1 to 11.44.1.6211.44.1.6362
611.44.1.64/2611.44.1.65 to 11.44.1.12611.44.1.12762
711.44.1.128/2611.44.1.129 to 11.44.1.19011.44.1.19162
811.44.1.192/2611.44.1.193 to 11.44.1.25411.44.1.25562
911.44.2.0/2611.44.2.1 to 11.44.2.6211.44.2.6362
1011.44.2.64/2611.44.2.65 to 11.44.2.12611.44.2.12762
1111.44.2.128/2611.44.2.129 to 11.44.2.19011.44.2.19162
1211.44.2.192/2611.44.2.193 to 11.44.2.25411.44.2.25562
1311.44.3.0/2611.44.3.1 to 11.44.3.6211.44.3.6362
1411.44.3.64/2611.44.3.65 to 11.44.3.12611.44.3.12762
1511.44.3.128/2611.44.3.129 to 11.44.3.19011.44.3.19162
1611.44.3.192/2611.44.3.193 to 11.44.3.25411.44.3.25562
1711.44.4.0/2611.44.4.1 to 11.44.4.6211.44.4.6362
1811.44.4.64/2611.44.4.65 to 11.44.4.12611.44.4.12762
1911.44.4.128/2611.44.4.129 to 11.44.4.19011.44.4.19162
2011.44.4.192/2611.44.4.193 to 11.44.4.25411.44.4.25562
2111.44.5.0/2611.44.5.1 to 11.44.5.6211.44.5.6362
2211.44.5.64/2611.44.5.65 to 11.44.5.12611.44.5.12762
2311.44.5.128/2611.44.5.129 to 11.44.5.19011.44.5.19162
2411.44.5.192/2611.44.5.193 to 11.44.5.25411.44.5.25562
2511.44.6.0/2611.44.6.1 to 11.44.6.6211.44.6.6362
2611.44.6.64/2611.44.6.65 to 11.44.6.12611.44.6.12762
2711.44.6.128/2611.44.6.129 to 11.44.6.19011.44.6.19162
2811.44.6.192/2611.44.6.193 to 11.44.6.25411.44.6.25562
2911.44.7.0/2611.44.7.1 to 11.44.7.6211.44.7.6362
3011.44.7.64/2611.44.7.65 to 11.44.7.12611.44.7.12762
3111.44.7.128/2611.44.7.129 to 11.44.7.19011.44.7.19162
3211.44.7.192/2611.44.7.193 to 11.44.7.25411.44.7.25562
3311.44.8.0/2611.44.8.1 to 11.44.8.6211.44.8.6362
3411.44.8.64/2611.44.8.65 to 11.44.8.12611.44.8.12762
3511.44.8.128/2611.44.8.129 to 11.44.8.19011.44.8.19162
3611.44.8.192/2611.44.8.193 to 11.44.8.25411.44.8.25562
3711.44.9.0/2611.44.9.1 to 11.44.9.6211.44.9.6362
3811.44.9.64/2611.44.9.65 to 11.44.9.12611.44.9.12762
3911.44.9.128/2611.44.9.129 to 11.44.9.19011.44.9.19162
4011.44.9.192/2611.44.9.193 to 11.44.9.25411.44.9.25562
4111.44.10.0/2611.44.10.1 to 11.44.10.6211.44.10.6362
4211.44.10.64/2611.44.10.65 to 11.44.10.12611.44.10.12762
4311.44.10.128/2611.44.10.129 to 11.44.10.19011.44.10.19162
4411.44.10.192/2611.44.10.193 to 11.44.10.25411.44.10.25562
4511.44.11.0/2611.44.11.1 to 11.44.11.6211.44.11.6362
4611.44.11.64/2611.44.11.65 to 11.44.11.12611.44.11.12762
4711.44.11.128/2611.44.11.129 to 11.44.11.19011.44.11.19162
4811.44.11.192/2611.44.11.193 to 11.44.11.25411.44.11.25562
4911.44.12.0/2611.44.12.1 to 11.44.12.6211.44.12.6362
5011.44.12.64/2611.44.12.65 to 11.44.12.12611.44.12.12762
5111.44.12.128/2611.44.12.129 to 11.44.12.19011.44.12.19162
5211.44.12.192/2611.44.12.193 to 11.44.12.25411.44.12.25562
5311.44.13.0/2611.44.13.1 to 11.44.13.6211.44.13.6362
5411.44.13.64/2611.44.13.65 to 11.44.13.12611.44.13.12762
5511.44.13.128/2611.44.13.129 to 11.44.13.19011.44.13.19162
5611.44.13.192/2611.44.13.193 to 11.44.13.25411.44.13.25562
5711.44.14.0/2611.44.14.1 to 11.44.14.6211.44.14.6362
5811.44.14.64/2611.44.14.65 to 11.44.14.12611.44.14.12762
5911.44.14.128/2611.44.14.129 to 11.44.14.19011.44.14.19162
6011.44.14.192/2611.44.14.193 to 11.44.14.25411.44.14.25562
6111.44.15.0/2611.44.15.1 to 11.44.15.6211.44.15.6362
6211.44.15.64/2611.44.15.65 to 11.44.15.12611.44.15.12762
6311.44.15.128/2611.44.15.129 to 11.44.15.19011.44.15.19162
6411.44.15.192/2611.44.15.193 to 11.44.15.25411.44.15.25562
6511.44.16.0/2611.44.16.1 to 11.44.16.6211.44.16.6362
6611.44.16.64/2611.44.16.65 to 11.44.16.12611.44.16.12762
6711.44.16.128/2611.44.16.129 to 11.44.16.19011.44.16.19162
6811.44.16.192/2611.44.16.193 to 11.44.16.25411.44.16.25562
6911.44.17.0/2611.44.17.1 to 11.44.17.6211.44.17.6362
7011.44.17.64/2611.44.17.65 to 11.44.17.12611.44.17.12762
7111.44.17.128/2611.44.17.129 to 11.44.17.19011.44.17.19162
7211.44.17.192/2611.44.17.193 to 11.44.17.25411.44.17.25562
7311.44.18.0/2611.44.18.1 to 11.44.18.6211.44.18.6362
7411.44.18.64/2611.44.18.65 to 11.44.18.12611.44.18.12762
7511.44.18.128/2611.44.18.129 to 11.44.18.19011.44.18.19162
7611.44.18.192/2611.44.18.193 to 11.44.18.25411.44.18.25562
7711.44.19.0/2611.44.19.1 to 11.44.19.6211.44.19.6362
7811.44.19.64/2611.44.19.65 to 11.44.19.12611.44.19.12762
7911.44.19.128/2611.44.19.129 to 11.44.19.19011.44.19.19162
8011.44.19.192/2611.44.19.193 to 11.44.19.25411.44.19.25562
8111.44.20.0/2611.44.20.1 to 11.44.20.6211.44.20.6362
8211.44.20.64/2611.44.20.65 to 11.44.20.12611.44.20.12762
8311.44.20.128/2611.44.20.129 to 11.44.20.19011.44.20.19162
8411.44.20.192/2611.44.20.193 to 11.44.20.25411.44.20.25562
8511.44.21.0/2611.44.21.1 to 11.44.21.6211.44.21.6362
8611.44.21.64/2611.44.21.65 to 11.44.21.12611.44.21.12762
8711.44.21.128/2611.44.21.129 to 11.44.21.19011.44.21.19162
8811.44.21.192/2611.44.21.193 to 11.44.21.25411.44.21.25562
8911.44.22.0/2611.44.22.1 to 11.44.22.6211.44.22.6362
9011.44.22.64/2611.44.22.65 to 11.44.22.12611.44.22.12762
9111.44.22.128/2611.44.22.129 to 11.44.22.19011.44.22.19162
9211.44.22.192/2611.44.22.193 to 11.44.22.25411.44.22.25562
9311.44.23.0/2611.44.23.1 to 11.44.23.6211.44.23.6362
9411.44.23.64/2611.44.23.65 to 11.44.23.12611.44.23.12762
9511.44.23.128/2611.44.23.129 to 11.44.23.19011.44.23.19162
9611.44.23.192/2611.44.23.193 to 11.44.23.25411.44.23.25562
9711.44.24.0/2611.44.24.1 to 11.44.24.6211.44.24.6362
9811.44.24.64/2611.44.24.65 to 11.44.24.12611.44.24.12762
9911.44.24.128/2611.44.24.129 to 11.44.24.19011.44.24.19162
10011.44.24.192/2611.44.24.193 to 11.44.24.25411.44.24.25562
10111.44.25.0/2611.44.25.1 to 11.44.25.6211.44.25.6362
10211.44.25.64/2611.44.25.65 to 11.44.25.12611.44.25.12762
10311.44.25.128/2611.44.25.129 to 11.44.25.19011.44.25.19162
10411.44.25.192/2611.44.25.193 to 11.44.25.25411.44.25.25562
10511.44.26.0/2611.44.26.1 to 11.44.26.6211.44.26.6362
10611.44.26.64/2611.44.26.65 to 11.44.26.12611.44.26.12762
10711.44.26.128/2611.44.26.129 to 11.44.26.19011.44.26.19162
10811.44.26.192/2611.44.26.193 to 11.44.26.25411.44.26.25562
10911.44.27.0/2611.44.27.1 to 11.44.27.6211.44.27.6362
11011.44.27.64/2611.44.27.65 to 11.44.27.12611.44.27.12762
11111.44.27.128/2611.44.27.129 to 11.44.27.19011.44.27.19162
11211.44.27.192/2611.44.27.193 to 11.44.27.25411.44.27.25562
11311.44.28.0/2611.44.28.1 to 11.44.28.6211.44.28.6362
11411.44.28.64/2611.44.28.65 to 11.44.28.12611.44.28.12762
11511.44.28.128/2611.44.28.129 to 11.44.28.19011.44.28.19162
11611.44.28.192/2611.44.28.193 to 11.44.28.25411.44.28.25562
11711.44.29.0/2611.44.29.1 to 11.44.29.6211.44.29.6362
11811.44.29.64/2611.44.29.65 to 11.44.29.12611.44.29.12762
11911.44.29.128/2611.44.29.129 to 11.44.29.19011.44.29.19162
12011.44.29.192/2611.44.29.193 to 11.44.29.25411.44.29.25562
12111.44.30.0/2611.44.30.1 to 11.44.30.6211.44.30.6362
12211.44.30.64/2611.44.30.65 to 11.44.30.12611.44.30.12762
12311.44.30.128/2611.44.30.129 to 11.44.30.19011.44.30.19162
12411.44.30.192/2611.44.30.193 to 11.44.30.25411.44.30.25562
12511.44.31.0/2611.44.31.1 to 11.44.31.6211.44.31.6362
12611.44.31.64/2611.44.31.65 to 11.44.31.12611.44.31.12762
12711.44.31.128/2611.44.31.129 to 11.44.31.19011.44.31.19162
12811.44.31.192/2611.44.31.193 to 11.44.31.25411.44.31.25562
12911.44.32.0/2611.44.32.1 to 11.44.32.6211.44.32.6362
13011.44.32.64/2611.44.32.65 to 11.44.32.12611.44.32.12762
13111.44.32.128/2611.44.32.129 to 11.44.32.19011.44.32.19162
13211.44.32.192/2611.44.32.193 to 11.44.32.25411.44.32.25562
13311.44.33.0/2611.44.33.1 to 11.44.33.6211.44.33.6362
13411.44.33.64/2611.44.33.65 to 11.44.33.12611.44.33.12762
13511.44.33.128/2611.44.33.129 to 11.44.33.19011.44.33.19162
13611.44.33.192/2611.44.33.193 to 11.44.33.25411.44.33.25562
13711.44.34.0/2611.44.34.1 to 11.44.34.6211.44.34.6362
13811.44.34.64/2611.44.34.65 to 11.44.34.12611.44.34.12762
13911.44.34.128/2611.44.34.129 to 11.44.34.19011.44.34.19162
14011.44.34.192/2611.44.34.193 to 11.44.34.25411.44.34.25562
14111.44.35.0/2611.44.35.1 to 11.44.35.6211.44.35.6362
14211.44.35.64/2611.44.35.65 to 11.44.35.12611.44.35.12762
14311.44.35.128/2611.44.35.129 to 11.44.35.19011.44.35.19162
14411.44.35.192/2611.44.35.193 to 11.44.35.25411.44.35.25562
14511.44.36.0/2611.44.36.1 to 11.44.36.6211.44.36.6362
14611.44.36.64/2611.44.36.65 to 11.44.36.12611.44.36.12762
14711.44.36.128/2611.44.36.129 to 11.44.36.19011.44.36.19162
14811.44.36.192/2611.44.36.193 to 11.44.36.25411.44.36.25562
14911.44.37.0/2611.44.37.1 to 11.44.37.6211.44.37.6362
15011.44.37.64/2611.44.37.65 to 11.44.37.12611.44.37.12762
15111.44.37.128/2611.44.37.129 to 11.44.37.19011.44.37.19162
15211.44.37.192/2611.44.37.193 to 11.44.37.25411.44.37.25562
15311.44.38.0/2611.44.38.1 to 11.44.38.6211.44.38.6362
15411.44.38.64/2611.44.38.65 to 11.44.38.12611.44.38.12762
15511.44.38.128/2611.44.38.129 to 11.44.38.19011.44.38.19162
15611.44.38.192/2611.44.38.193 to 11.44.38.25411.44.38.25562
15711.44.39.0/2611.44.39.1 to 11.44.39.6211.44.39.6362
15811.44.39.64/2611.44.39.65 to 11.44.39.12611.44.39.12762
15911.44.39.128/2611.44.39.129 to 11.44.39.19011.44.39.19162
16011.44.39.192/2611.44.39.193 to 11.44.39.25411.44.39.25562
16111.44.40.0/2611.44.40.1 to 11.44.40.6211.44.40.6362
16211.44.40.64/2611.44.40.65 to 11.44.40.12611.44.40.12762
16311.44.40.128/2611.44.40.129 to 11.44.40.19011.44.40.19162
16411.44.40.192/2611.44.40.193 to 11.44.40.25411.44.40.25562
16511.44.41.0/2611.44.41.1 to 11.44.41.6211.44.41.6362
16611.44.41.64/2611.44.41.65 to 11.44.41.12611.44.41.12762
16711.44.41.128/2611.44.41.129 to 11.44.41.19011.44.41.19162
16811.44.41.192/2611.44.41.193 to 11.44.41.25411.44.41.25562
16911.44.42.0/2611.44.42.1 to 11.44.42.6211.44.42.6362
17011.44.42.64/2611.44.42.65 to 11.44.42.12611.44.42.12762
17111.44.42.128/2611.44.42.129 to 11.44.42.19011.44.42.19162
17211.44.42.192/2611.44.42.193 to 11.44.42.25411.44.42.25562
17311.44.43.0/2611.44.43.1 to 11.44.43.6211.44.43.6362
17411.44.43.64/2611.44.43.65 to 11.44.43.12611.44.43.12762
17511.44.43.128/2611.44.43.129 to 11.44.43.19011.44.43.19162
17611.44.43.192/2611.44.43.193 to 11.44.43.25411.44.43.25562
17711.44.44.0/2611.44.44.1 to 11.44.44.6211.44.44.6362
17811.44.44.64/2611.44.44.65 to 11.44.44.12611.44.44.12762
17911.44.44.128/2611.44.44.129 to 11.44.44.19011.44.44.19162
18011.44.44.192/2611.44.44.193 to 11.44.44.25411.44.44.25562
18111.44.45.0/2611.44.45.1 to 11.44.45.6211.44.45.6362
18211.44.45.64/2611.44.45.65 to 11.44.45.12611.44.45.12762
18311.44.45.128/2611.44.45.129 to 11.44.45.19011.44.45.19162
18411.44.45.192/2611.44.45.193 to 11.44.45.25411.44.45.25562
18511.44.46.0/2611.44.46.1 to 11.44.46.6211.44.46.6362
18611.44.46.64/2611.44.46.65 to 11.44.46.12611.44.46.12762
18711.44.46.128/2611.44.46.129 to 11.44.46.19011.44.46.19162
18811.44.46.192/2611.44.46.193 to 11.44.46.25411.44.46.25562
18911.44.47.0/2611.44.47.1 to 11.44.47.6211.44.47.6362
19011.44.47.64/2611.44.47.65 to 11.44.47.12611.44.47.12762
19111.44.47.128/2611.44.47.129 to 11.44.47.19011.44.47.19162
19211.44.47.192/2611.44.47.193 to 11.44.47.25411.44.47.25562
19311.44.48.0/2611.44.48.1 to 11.44.48.6211.44.48.6362
19411.44.48.64/2611.44.48.65 to 11.44.48.12611.44.48.12762
19511.44.48.128/2611.44.48.129 to 11.44.48.19011.44.48.19162
19611.44.48.192/2611.44.48.193 to 11.44.48.25411.44.48.25562
19711.44.49.0/2611.44.49.1 to 11.44.49.6211.44.49.6362
19811.44.49.64/2611.44.49.65 to 11.44.49.12611.44.49.12762
19911.44.49.128/2611.44.49.129 to 11.44.49.19011.44.49.19162
20011.44.49.192/2611.44.49.193 to 11.44.49.25411.44.49.25562
20111.44.50.0/2611.44.50.1 to 11.44.50.6211.44.50.6362
20211.44.50.64/2611.44.50.65 to 11.44.50.12611.44.50.12762
20311.44.50.128/2611.44.50.129 to 11.44.50.19011.44.50.19162
20411.44.50.192/2611.44.50.193 to 11.44.50.25411.44.50.25562
20511.44.51.0/2611.44.51.1 to 11.44.51.6211.44.51.6362
20611.44.51.64/2611.44.51.65 to 11.44.51.12611.44.51.12762
20711.44.51.128/2611.44.51.129 to 11.44.51.19011.44.51.19162
20811.44.51.192/2611.44.51.193 to 11.44.51.25411.44.51.25562
20911.44.52.0/2611.44.52.1 to 11.44.52.6211.44.52.6362
21011.44.52.64/2611.44.52.65 to 11.44.52.12611.44.52.12762
21111.44.52.128/2611.44.52.129 to 11.44.52.19011.44.52.19162
21211.44.52.192/2611.44.52.193 to 11.44.52.25411.44.52.25562
21311.44.53.0/2611.44.53.1 to 11.44.53.6211.44.53.6362
21411.44.53.64/2611.44.53.65 to 11.44.53.12611.44.53.12762
21511.44.53.128/2611.44.53.129 to 11.44.53.19011.44.53.19162
21611.44.53.192/2611.44.53.193 to 11.44.53.25411.44.53.25562
21711.44.54.0/2611.44.54.1 to 11.44.54.6211.44.54.6362
21811.44.54.64/2611.44.54.65 to 11.44.54.12611.44.54.12762
21911.44.54.128/2611.44.54.129 to 11.44.54.19011.44.54.19162
22011.44.54.192/2611.44.54.193 to 11.44.54.25411.44.54.25562
22111.44.55.0/2611.44.55.1 to 11.44.55.6211.44.55.6362
22211.44.55.64/2611.44.55.65 to 11.44.55.12611.44.55.12762
22311.44.55.128/2611.44.55.129 to 11.44.55.19011.44.55.19162
22411.44.55.192/2611.44.55.193 to 11.44.55.25411.44.55.25562
22511.44.56.0/2611.44.56.1 to 11.44.56.6211.44.56.6362
22611.44.56.64/2611.44.56.65 to 11.44.56.12611.44.56.12762
22711.44.56.128/2611.44.56.129 to 11.44.56.19011.44.56.19162
22811.44.56.192/2611.44.56.193 to 11.44.56.25411.44.56.25562
22911.44.57.0/2611.44.57.1 to 11.44.57.6211.44.57.6362
23011.44.57.64/2611.44.57.65 to 11.44.57.12611.44.57.12762
23111.44.57.128/2611.44.57.129 to 11.44.57.19011.44.57.19162
23211.44.57.192/2611.44.57.193 to 11.44.57.25411.44.57.25562
23311.44.58.0/2611.44.58.1 to 11.44.58.6211.44.58.6362
23411.44.58.64/2611.44.58.65 to 11.44.58.12611.44.58.12762
23511.44.58.128/2611.44.58.129 to 11.44.58.19011.44.58.19162
23611.44.58.192/2611.44.58.193 to 11.44.58.25411.44.58.25562
23711.44.59.0/2611.44.59.1 to 11.44.59.6211.44.59.6362
23811.44.59.64/2611.44.59.65 to 11.44.59.12611.44.59.12762
23911.44.59.128/2611.44.59.129 to 11.44.59.19011.44.59.19162
24011.44.59.192/2611.44.59.193 to 11.44.59.25411.44.59.25562
24111.44.60.0/2611.44.60.1 to 11.44.60.6211.44.60.6362
24211.44.60.64/2611.44.60.65 to 11.44.60.12611.44.60.12762
24311.44.60.128/2611.44.60.129 to 11.44.60.19011.44.60.19162
24411.44.60.192/2611.44.60.193 to 11.44.60.25411.44.60.25562
24511.44.61.0/2611.44.61.1 to 11.44.61.6211.44.61.6362
24611.44.61.64/2611.44.61.65 to 11.44.61.12611.44.61.12762
24711.44.61.128/2611.44.61.129 to 11.44.61.19011.44.61.19162
24811.44.61.192/2611.44.61.193 to 11.44.61.25411.44.61.25562
24911.44.62.0/2611.44.62.1 to 11.44.62.6211.44.62.6362
25011.44.62.64/2611.44.62.65 to 11.44.62.12611.44.62.12762
25111.44.62.128/2611.44.62.129 to 11.44.62.19011.44.62.19162
25211.44.62.192/2611.44.62.193 to 11.44.62.25411.44.62.25562
25311.44.63.0/2611.44.63.1 to 11.44.63.6211.44.63.6362
25411.44.63.64/2611.44.63.65 to 11.44.63.12611.44.63.12762
25511.44.63.128/2611.44.63.129 to 11.44.63.19011.44.63.19162
25611.44.63.192/2611.44.63.193 to 11.44.63.25411.44.63.25562

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.