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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.

Network44.167.0.0/18
Usable hosts16,382
Subnet mask255.255.192.0
Addresses16,384
Network address
44.167.0.0
Broadcast address
44.167.63.255
First usable
44.167.0.1
Last usable
44.167.63.254
Usable hosts
16,382 (16,384 less the network and broadcast addresses)
Subnet mask
255.255.192.0
Wildcard mask
0.0.63.255 (Cisco ACLs, OSPF)
Prefix length
/18
Type
Public public
Old class
A (default /8)
As numbers
Hex 2CA70000 · Integer 749142016 to 749158399
Reverse DNS zones
0.167.44.in-addr.arpa
1.167.44.in-addr.arpa
2.167.44.in-addr.arpa
3.167.44.in-addr.arpa
4.167.44.in-addr.arpa
5.167.44.in-addr.arpa
6.167.44.in-addr.arpa
7.167.44.in-addr.arpa
8.167.44.in-addr.arpa
9.167.44.in-addr.arpa
10.167.44.in-addr.arpa
11.167.44.in-addr.arpa
12.167.44.in-addr.arpa
13.167.44.in-addr.arpa
14.167.44.in-addr.arpa
15.167.44.in-addr.arpa
and 48 more
/18 is not on a 8-bit boundary, so it takes 64 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101100.10100111.00000000.0000000044.167.0.0
Subnet mask11111111.11111111.11000000.00000000255.255.192.0
Network00101100.10100111.00000000.0000000044.167.0.0
Broadcast00101100.10100111.00111111.1111111144.167.63.255
Split into smaller subnets/26
/19 (2)/20 (4)/21 (8)/22 (16)/23 (32)/24 (64)/25 (128)/26 (256)/27 (512)/28 (1,024)/29 (2,048)/30 (4,096)

44.167.0.0/18 makes 256 subnets of /26.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
144.167.0.0/2644.167.0.1 to 44.167.0.6244.167.0.6362
244.167.0.64/2644.167.0.65 to 44.167.0.12644.167.0.12762
344.167.0.128/2644.167.0.129 to 44.167.0.19044.167.0.19162
444.167.0.192/2644.167.0.193 to 44.167.0.25444.167.0.25562
544.167.1.0/2644.167.1.1 to 44.167.1.6244.167.1.6362
644.167.1.64/2644.167.1.65 to 44.167.1.12644.167.1.12762
744.167.1.128/2644.167.1.129 to 44.167.1.19044.167.1.19162
844.167.1.192/2644.167.1.193 to 44.167.1.25444.167.1.25562
944.167.2.0/2644.167.2.1 to 44.167.2.6244.167.2.6362
1044.167.2.64/2644.167.2.65 to 44.167.2.12644.167.2.12762
1144.167.2.128/2644.167.2.129 to 44.167.2.19044.167.2.19162
1244.167.2.192/2644.167.2.193 to 44.167.2.25444.167.2.25562
1344.167.3.0/2644.167.3.1 to 44.167.3.6244.167.3.6362
1444.167.3.64/2644.167.3.65 to 44.167.3.12644.167.3.12762
1544.167.3.128/2644.167.3.129 to 44.167.3.19044.167.3.19162
1644.167.3.192/2644.167.3.193 to 44.167.3.25444.167.3.25562
1744.167.4.0/2644.167.4.1 to 44.167.4.6244.167.4.6362
1844.167.4.64/2644.167.4.65 to 44.167.4.12644.167.4.12762
1944.167.4.128/2644.167.4.129 to 44.167.4.19044.167.4.19162
2044.167.4.192/2644.167.4.193 to 44.167.4.25444.167.4.25562
2144.167.5.0/2644.167.5.1 to 44.167.5.6244.167.5.6362
2244.167.5.64/2644.167.5.65 to 44.167.5.12644.167.5.12762
2344.167.5.128/2644.167.5.129 to 44.167.5.19044.167.5.19162
2444.167.5.192/2644.167.5.193 to 44.167.5.25444.167.5.25562
2544.167.6.0/2644.167.6.1 to 44.167.6.6244.167.6.6362
2644.167.6.64/2644.167.6.65 to 44.167.6.12644.167.6.12762
2744.167.6.128/2644.167.6.129 to 44.167.6.19044.167.6.19162
2844.167.6.192/2644.167.6.193 to 44.167.6.25444.167.6.25562
2944.167.7.0/2644.167.7.1 to 44.167.7.6244.167.7.6362
3044.167.7.64/2644.167.7.65 to 44.167.7.12644.167.7.12762
3144.167.7.128/2644.167.7.129 to 44.167.7.19044.167.7.19162
3244.167.7.192/2644.167.7.193 to 44.167.7.25444.167.7.25562
3344.167.8.0/2644.167.8.1 to 44.167.8.6244.167.8.6362
3444.167.8.64/2644.167.8.65 to 44.167.8.12644.167.8.12762
3544.167.8.128/2644.167.8.129 to 44.167.8.19044.167.8.19162
3644.167.8.192/2644.167.8.193 to 44.167.8.25444.167.8.25562
3744.167.9.0/2644.167.9.1 to 44.167.9.6244.167.9.6362
3844.167.9.64/2644.167.9.65 to 44.167.9.12644.167.9.12762
3944.167.9.128/2644.167.9.129 to 44.167.9.19044.167.9.19162
4044.167.9.192/2644.167.9.193 to 44.167.9.25444.167.9.25562
4144.167.10.0/2644.167.10.1 to 44.167.10.6244.167.10.6362
4244.167.10.64/2644.167.10.65 to 44.167.10.12644.167.10.12762
4344.167.10.128/2644.167.10.129 to 44.167.10.19044.167.10.19162
4444.167.10.192/2644.167.10.193 to 44.167.10.25444.167.10.25562
4544.167.11.0/2644.167.11.1 to 44.167.11.6244.167.11.6362
4644.167.11.64/2644.167.11.65 to 44.167.11.12644.167.11.12762
4744.167.11.128/2644.167.11.129 to 44.167.11.19044.167.11.19162
4844.167.11.192/2644.167.11.193 to 44.167.11.25444.167.11.25562
4944.167.12.0/2644.167.12.1 to 44.167.12.6244.167.12.6362
5044.167.12.64/2644.167.12.65 to 44.167.12.12644.167.12.12762
5144.167.12.128/2644.167.12.129 to 44.167.12.19044.167.12.19162
5244.167.12.192/2644.167.12.193 to 44.167.12.25444.167.12.25562
5344.167.13.0/2644.167.13.1 to 44.167.13.6244.167.13.6362
5444.167.13.64/2644.167.13.65 to 44.167.13.12644.167.13.12762
5544.167.13.128/2644.167.13.129 to 44.167.13.19044.167.13.19162
5644.167.13.192/2644.167.13.193 to 44.167.13.25444.167.13.25562
5744.167.14.0/2644.167.14.1 to 44.167.14.6244.167.14.6362
5844.167.14.64/2644.167.14.65 to 44.167.14.12644.167.14.12762
5944.167.14.128/2644.167.14.129 to 44.167.14.19044.167.14.19162
6044.167.14.192/2644.167.14.193 to 44.167.14.25444.167.14.25562
6144.167.15.0/2644.167.15.1 to 44.167.15.6244.167.15.6362
6244.167.15.64/2644.167.15.65 to 44.167.15.12644.167.15.12762
6344.167.15.128/2644.167.15.129 to 44.167.15.19044.167.15.19162
6444.167.15.192/2644.167.15.193 to 44.167.15.25444.167.15.25562
6544.167.16.0/2644.167.16.1 to 44.167.16.6244.167.16.6362
6644.167.16.64/2644.167.16.65 to 44.167.16.12644.167.16.12762
6744.167.16.128/2644.167.16.129 to 44.167.16.19044.167.16.19162
6844.167.16.192/2644.167.16.193 to 44.167.16.25444.167.16.25562
6944.167.17.0/2644.167.17.1 to 44.167.17.6244.167.17.6362
7044.167.17.64/2644.167.17.65 to 44.167.17.12644.167.17.12762
7144.167.17.128/2644.167.17.129 to 44.167.17.19044.167.17.19162
7244.167.17.192/2644.167.17.193 to 44.167.17.25444.167.17.25562
7344.167.18.0/2644.167.18.1 to 44.167.18.6244.167.18.6362
7444.167.18.64/2644.167.18.65 to 44.167.18.12644.167.18.12762
7544.167.18.128/2644.167.18.129 to 44.167.18.19044.167.18.19162
7644.167.18.192/2644.167.18.193 to 44.167.18.25444.167.18.25562
7744.167.19.0/2644.167.19.1 to 44.167.19.6244.167.19.6362
7844.167.19.64/2644.167.19.65 to 44.167.19.12644.167.19.12762
7944.167.19.128/2644.167.19.129 to 44.167.19.19044.167.19.19162
8044.167.19.192/2644.167.19.193 to 44.167.19.25444.167.19.25562
8144.167.20.0/2644.167.20.1 to 44.167.20.6244.167.20.6362
8244.167.20.64/2644.167.20.65 to 44.167.20.12644.167.20.12762
8344.167.20.128/2644.167.20.129 to 44.167.20.19044.167.20.19162
8444.167.20.192/2644.167.20.193 to 44.167.20.25444.167.20.25562
8544.167.21.0/2644.167.21.1 to 44.167.21.6244.167.21.6362
8644.167.21.64/2644.167.21.65 to 44.167.21.12644.167.21.12762
8744.167.21.128/2644.167.21.129 to 44.167.21.19044.167.21.19162
8844.167.21.192/2644.167.21.193 to 44.167.21.25444.167.21.25562
8944.167.22.0/2644.167.22.1 to 44.167.22.6244.167.22.6362
9044.167.22.64/2644.167.22.65 to 44.167.22.12644.167.22.12762
9144.167.22.128/2644.167.22.129 to 44.167.22.19044.167.22.19162
9244.167.22.192/2644.167.22.193 to 44.167.22.25444.167.22.25562
9344.167.23.0/2644.167.23.1 to 44.167.23.6244.167.23.6362
9444.167.23.64/2644.167.23.65 to 44.167.23.12644.167.23.12762
9544.167.23.128/2644.167.23.129 to 44.167.23.19044.167.23.19162
9644.167.23.192/2644.167.23.193 to 44.167.23.25444.167.23.25562
9744.167.24.0/2644.167.24.1 to 44.167.24.6244.167.24.6362
9844.167.24.64/2644.167.24.65 to 44.167.24.12644.167.24.12762
9944.167.24.128/2644.167.24.129 to 44.167.24.19044.167.24.19162
10044.167.24.192/2644.167.24.193 to 44.167.24.25444.167.24.25562
10144.167.25.0/2644.167.25.1 to 44.167.25.6244.167.25.6362
10244.167.25.64/2644.167.25.65 to 44.167.25.12644.167.25.12762
10344.167.25.128/2644.167.25.129 to 44.167.25.19044.167.25.19162
10444.167.25.192/2644.167.25.193 to 44.167.25.25444.167.25.25562
10544.167.26.0/2644.167.26.1 to 44.167.26.6244.167.26.6362
10644.167.26.64/2644.167.26.65 to 44.167.26.12644.167.26.12762
10744.167.26.128/2644.167.26.129 to 44.167.26.19044.167.26.19162
10844.167.26.192/2644.167.26.193 to 44.167.26.25444.167.26.25562
10944.167.27.0/2644.167.27.1 to 44.167.27.6244.167.27.6362
11044.167.27.64/2644.167.27.65 to 44.167.27.12644.167.27.12762
11144.167.27.128/2644.167.27.129 to 44.167.27.19044.167.27.19162
11244.167.27.192/2644.167.27.193 to 44.167.27.25444.167.27.25562
11344.167.28.0/2644.167.28.1 to 44.167.28.6244.167.28.6362
11444.167.28.64/2644.167.28.65 to 44.167.28.12644.167.28.12762
11544.167.28.128/2644.167.28.129 to 44.167.28.19044.167.28.19162
11644.167.28.192/2644.167.28.193 to 44.167.28.25444.167.28.25562
11744.167.29.0/2644.167.29.1 to 44.167.29.6244.167.29.6362
11844.167.29.64/2644.167.29.65 to 44.167.29.12644.167.29.12762
11944.167.29.128/2644.167.29.129 to 44.167.29.19044.167.29.19162
12044.167.29.192/2644.167.29.193 to 44.167.29.25444.167.29.25562
12144.167.30.0/2644.167.30.1 to 44.167.30.6244.167.30.6362
12244.167.30.64/2644.167.30.65 to 44.167.30.12644.167.30.12762
12344.167.30.128/2644.167.30.129 to 44.167.30.19044.167.30.19162
12444.167.30.192/2644.167.30.193 to 44.167.30.25444.167.30.25562
12544.167.31.0/2644.167.31.1 to 44.167.31.6244.167.31.6362
12644.167.31.64/2644.167.31.65 to 44.167.31.12644.167.31.12762
12744.167.31.128/2644.167.31.129 to 44.167.31.19044.167.31.19162
12844.167.31.192/2644.167.31.193 to 44.167.31.25444.167.31.25562
12944.167.32.0/2644.167.32.1 to 44.167.32.6244.167.32.6362
13044.167.32.64/2644.167.32.65 to 44.167.32.12644.167.32.12762
13144.167.32.128/2644.167.32.129 to 44.167.32.19044.167.32.19162
13244.167.32.192/2644.167.32.193 to 44.167.32.25444.167.32.25562
13344.167.33.0/2644.167.33.1 to 44.167.33.6244.167.33.6362
13444.167.33.64/2644.167.33.65 to 44.167.33.12644.167.33.12762
13544.167.33.128/2644.167.33.129 to 44.167.33.19044.167.33.19162
13644.167.33.192/2644.167.33.193 to 44.167.33.25444.167.33.25562
13744.167.34.0/2644.167.34.1 to 44.167.34.6244.167.34.6362
13844.167.34.64/2644.167.34.65 to 44.167.34.12644.167.34.12762
13944.167.34.128/2644.167.34.129 to 44.167.34.19044.167.34.19162
14044.167.34.192/2644.167.34.193 to 44.167.34.25444.167.34.25562
14144.167.35.0/2644.167.35.1 to 44.167.35.6244.167.35.6362
14244.167.35.64/2644.167.35.65 to 44.167.35.12644.167.35.12762
14344.167.35.128/2644.167.35.129 to 44.167.35.19044.167.35.19162
14444.167.35.192/2644.167.35.193 to 44.167.35.25444.167.35.25562
14544.167.36.0/2644.167.36.1 to 44.167.36.6244.167.36.6362
14644.167.36.64/2644.167.36.65 to 44.167.36.12644.167.36.12762
14744.167.36.128/2644.167.36.129 to 44.167.36.19044.167.36.19162
14844.167.36.192/2644.167.36.193 to 44.167.36.25444.167.36.25562
14944.167.37.0/2644.167.37.1 to 44.167.37.6244.167.37.6362
15044.167.37.64/2644.167.37.65 to 44.167.37.12644.167.37.12762
15144.167.37.128/2644.167.37.129 to 44.167.37.19044.167.37.19162
15244.167.37.192/2644.167.37.193 to 44.167.37.25444.167.37.25562
15344.167.38.0/2644.167.38.1 to 44.167.38.6244.167.38.6362
15444.167.38.64/2644.167.38.65 to 44.167.38.12644.167.38.12762
15544.167.38.128/2644.167.38.129 to 44.167.38.19044.167.38.19162
15644.167.38.192/2644.167.38.193 to 44.167.38.25444.167.38.25562
15744.167.39.0/2644.167.39.1 to 44.167.39.6244.167.39.6362
15844.167.39.64/2644.167.39.65 to 44.167.39.12644.167.39.12762
15944.167.39.128/2644.167.39.129 to 44.167.39.19044.167.39.19162
16044.167.39.192/2644.167.39.193 to 44.167.39.25444.167.39.25562
16144.167.40.0/2644.167.40.1 to 44.167.40.6244.167.40.6362
16244.167.40.64/2644.167.40.65 to 44.167.40.12644.167.40.12762
16344.167.40.128/2644.167.40.129 to 44.167.40.19044.167.40.19162
16444.167.40.192/2644.167.40.193 to 44.167.40.25444.167.40.25562
16544.167.41.0/2644.167.41.1 to 44.167.41.6244.167.41.6362
16644.167.41.64/2644.167.41.65 to 44.167.41.12644.167.41.12762
16744.167.41.128/2644.167.41.129 to 44.167.41.19044.167.41.19162
16844.167.41.192/2644.167.41.193 to 44.167.41.25444.167.41.25562
16944.167.42.0/2644.167.42.1 to 44.167.42.6244.167.42.6362
17044.167.42.64/2644.167.42.65 to 44.167.42.12644.167.42.12762
17144.167.42.128/2644.167.42.129 to 44.167.42.19044.167.42.19162
17244.167.42.192/2644.167.42.193 to 44.167.42.25444.167.42.25562
17344.167.43.0/2644.167.43.1 to 44.167.43.6244.167.43.6362
17444.167.43.64/2644.167.43.65 to 44.167.43.12644.167.43.12762
17544.167.43.128/2644.167.43.129 to 44.167.43.19044.167.43.19162
17644.167.43.192/2644.167.43.193 to 44.167.43.25444.167.43.25562
17744.167.44.0/2644.167.44.1 to 44.167.44.6244.167.44.6362
17844.167.44.64/2644.167.44.65 to 44.167.44.12644.167.44.12762
17944.167.44.128/2644.167.44.129 to 44.167.44.19044.167.44.19162
18044.167.44.192/2644.167.44.193 to 44.167.44.25444.167.44.25562
18144.167.45.0/2644.167.45.1 to 44.167.45.6244.167.45.6362
18244.167.45.64/2644.167.45.65 to 44.167.45.12644.167.45.12762
18344.167.45.128/2644.167.45.129 to 44.167.45.19044.167.45.19162
18444.167.45.192/2644.167.45.193 to 44.167.45.25444.167.45.25562
18544.167.46.0/2644.167.46.1 to 44.167.46.6244.167.46.6362
18644.167.46.64/2644.167.46.65 to 44.167.46.12644.167.46.12762
18744.167.46.128/2644.167.46.129 to 44.167.46.19044.167.46.19162
18844.167.46.192/2644.167.46.193 to 44.167.46.25444.167.46.25562
18944.167.47.0/2644.167.47.1 to 44.167.47.6244.167.47.6362
19044.167.47.64/2644.167.47.65 to 44.167.47.12644.167.47.12762
19144.167.47.128/2644.167.47.129 to 44.167.47.19044.167.47.19162
19244.167.47.192/2644.167.47.193 to 44.167.47.25444.167.47.25562
19344.167.48.0/2644.167.48.1 to 44.167.48.6244.167.48.6362
19444.167.48.64/2644.167.48.65 to 44.167.48.12644.167.48.12762
19544.167.48.128/2644.167.48.129 to 44.167.48.19044.167.48.19162
19644.167.48.192/2644.167.48.193 to 44.167.48.25444.167.48.25562
19744.167.49.0/2644.167.49.1 to 44.167.49.6244.167.49.6362
19844.167.49.64/2644.167.49.65 to 44.167.49.12644.167.49.12762
19944.167.49.128/2644.167.49.129 to 44.167.49.19044.167.49.19162
20044.167.49.192/2644.167.49.193 to 44.167.49.25444.167.49.25562
20144.167.50.0/2644.167.50.1 to 44.167.50.6244.167.50.6362
20244.167.50.64/2644.167.50.65 to 44.167.50.12644.167.50.12762
20344.167.50.128/2644.167.50.129 to 44.167.50.19044.167.50.19162
20444.167.50.192/2644.167.50.193 to 44.167.50.25444.167.50.25562
20544.167.51.0/2644.167.51.1 to 44.167.51.6244.167.51.6362
20644.167.51.64/2644.167.51.65 to 44.167.51.12644.167.51.12762
20744.167.51.128/2644.167.51.129 to 44.167.51.19044.167.51.19162
20844.167.51.192/2644.167.51.193 to 44.167.51.25444.167.51.25562
20944.167.52.0/2644.167.52.1 to 44.167.52.6244.167.52.6362
21044.167.52.64/2644.167.52.65 to 44.167.52.12644.167.52.12762
21144.167.52.128/2644.167.52.129 to 44.167.52.19044.167.52.19162
21244.167.52.192/2644.167.52.193 to 44.167.52.25444.167.52.25562
21344.167.53.0/2644.167.53.1 to 44.167.53.6244.167.53.6362
21444.167.53.64/2644.167.53.65 to 44.167.53.12644.167.53.12762
21544.167.53.128/2644.167.53.129 to 44.167.53.19044.167.53.19162
21644.167.53.192/2644.167.53.193 to 44.167.53.25444.167.53.25562
21744.167.54.0/2644.167.54.1 to 44.167.54.6244.167.54.6362
21844.167.54.64/2644.167.54.65 to 44.167.54.12644.167.54.12762
21944.167.54.128/2644.167.54.129 to 44.167.54.19044.167.54.19162
22044.167.54.192/2644.167.54.193 to 44.167.54.25444.167.54.25562
22144.167.55.0/2644.167.55.1 to 44.167.55.6244.167.55.6362
22244.167.55.64/2644.167.55.65 to 44.167.55.12644.167.55.12762
22344.167.55.128/2644.167.55.129 to 44.167.55.19044.167.55.19162
22444.167.55.192/2644.167.55.193 to 44.167.55.25444.167.55.25562
22544.167.56.0/2644.167.56.1 to 44.167.56.6244.167.56.6362
22644.167.56.64/2644.167.56.65 to 44.167.56.12644.167.56.12762
22744.167.56.128/2644.167.56.129 to 44.167.56.19044.167.56.19162
22844.167.56.192/2644.167.56.193 to 44.167.56.25444.167.56.25562
22944.167.57.0/2644.167.57.1 to 44.167.57.6244.167.57.6362
23044.167.57.64/2644.167.57.65 to 44.167.57.12644.167.57.12762
23144.167.57.128/2644.167.57.129 to 44.167.57.19044.167.57.19162
23244.167.57.192/2644.167.57.193 to 44.167.57.25444.167.57.25562
23344.167.58.0/2644.167.58.1 to 44.167.58.6244.167.58.6362
23444.167.58.64/2644.167.58.65 to 44.167.58.12644.167.58.12762
23544.167.58.128/2644.167.58.129 to 44.167.58.19044.167.58.19162
23644.167.58.192/2644.167.58.193 to 44.167.58.25444.167.58.25562
23744.167.59.0/2644.167.59.1 to 44.167.59.6244.167.59.6362
23844.167.59.64/2644.167.59.65 to 44.167.59.12644.167.59.12762
23944.167.59.128/2644.167.59.129 to 44.167.59.19044.167.59.19162
24044.167.59.192/2644.167.59.193 to 44.167.59.25444.167.59.25562
24144.167.60.0/2644.167.60.1 to 44.167.60.6244.167.60.6362
24244.167.60.64/2644.167.60.65 to 44.167.60.12644.167.60.12762
24344.167.60.128/2644.167.60.129 to 44.167.60.19044.167.60.19162
24444.167.60.192/2644.167.60.193 to 44.167.60.25444.167.60.25562
24544.167.61.0/2644.167.61.1 to 44.167.61.6244.167.61.6362
24644.167.61.64/2644.167.61.65 to 44.167.61.12644.167.61.12762
24744.167.61.128/2644.167.61.129 to 44.167.61.19044.167.61.19162
24844.167.61.192/2644.167.61.193 to 44.167.61.25444.167.61.25562
24944.167.62.0/2644.167.62.1 to 44.167.62.6244.167.62.6362
25044.167.62.64/2644.167.62.65 to 44.167.62.12644.167.62.12762
25144.167.62.128/2644.167.62.129 to 44.167.62.19044.167.62.19162
25244.167.62.192/2644.167.62.193 to 44.167.62.25444.167.62.25562
25344.167.63.0/2644.167.63.1 to 44.167.63.6244.167.63.6362
25444.167.63.64/2644.167.63.65 to 44.167.63.12644.167.63.12762
25544.167.63.128/2644.167.63.129 to 44.167.63.19044.167.63.19162
25644.167.63.192/2644.167.63.193 to 44.167.63.25444.167.63.25562

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.