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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.

Network86.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
86.0.0.0
Broadcast address
86.127.255.255
First usable
86.0.0.1
Last usable
86.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 56000000 · Integer 1442840576 to 1451229183
Reverse DNS zones
0.86.in-addr.arpa
1.86.in-addr.arpa
2.86.in-addr.arpa
3.86.in-addr.arpa
4.86.in-addr.arpa
5.86.in-addr.arpa
6.86.in-addr.arpa
7.86.in-addr.arpa
8.86.in-addr.arpa
9.86.in-addr.arpa
10.86.in-addr.arpa
11.86.in-addr.arpa
12.86.in-addr.arpa
13.86.in-addr.arpa
14.86.in-addr.arpa
15.86.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010110.00000000.00000000.0000000086.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01010110.00000000.00000000.0000000086.0.0.0
Broadcast01010110.01111111.11111111.1111111186.127.255.255
Split into smaller subnets/17
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

86.0.0.0/9 makes 256 subnets of /17.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
186.0.0.0/1786.0.0.1 to 86.0.127.25486.0.127.25532,766
286.0.128.0/1786.0.128.1 to 86.0.255.25486.0.255.25532,766
386.1.0.0/1786.1.0.1 to 86.1.127.25486.1.127.25532,766
486.1.128.0/1786.1.128.1 to 86.1.255.25486.1.255.25532,766
586.2.0.0/1786.2.0.1 to 86.2.127.25486.2.127.25532,766
686.2.128.0/1786.2.128.1 to 86.2.255.25486.2.255.25532,766
786.3.0.0/1786.3.0.1 to 86.3.127.25486.3.127.25532,766
886.3.128.0/1786.3.128.1 to 86.3.255.25486.3.255.25532,766
986.4.0.0/1786.4.0.1 to 86.4.127.25486.4.127.25532,766
1086.4.128.0/1786.4.128.1 to 86.4.255.25486.4.255.25532,766
1186.5.0.0/1786.5.0.1 to 86.5.127.25486.5.127.25532,766
1286.5.128.0/1786.5.128.1 to 86.5.255.25486.5.255.25532,766
1386.6.0.0/1786.6.0.1 to 86.6.127.25486.6.127.25532,766
1486.6.128.0/1786.6.128.1 to 86.6.255.25486.6.255.25532,766
1586.7.0.0/1786.7.0.1 to 86.7.127.25486.7.127.25532,766
1686.7.128.0/1786.7.128.1 to 86.7.255.25486.7.255.25532,766
1786.8.0.0/1786.8.0.1 to 86.8.127.25486.8.127.25532,766
1886.8.128.0/1786.8.128.1 to 86.8.255.25486.8.255.25532,766
1986.9.0.0/1786.9.0.1 to 86.9.127.25486.9.127.25532,766
2086.9.128.0/1786.9.128.1 to 86.9.255.25486.9.255.25532,766
2186.10.0.0/1786.10.0.1 to 86.10.127.25486.10.127.25532,766
2286.10.128.0/1786.10.128.1 to 86.10.255.25486.10.255.25532,766
2386.11.0.0/1786.11.0.1 to 86.11.127.25486.11.127.25532,766
2486.11.128.0/1786.11.128.1 to 86.11.255.25486.11.255.25532,766
2586.12.0.0/1786.12.0.1 to 86.12.127.25486.12.127.25532,766
2686.12.128.0/1786.12.128.1 to 86.12.255.25486.12.255.25532,766
2786.13.0.0/1786.13.0.1 to 86.13.127.25486.13.127.25532,766
2886.13.128.0/1786.13.128.1 to 86.13.255.25486.13.255.25532,766
2986.14.0.0/1786.14.0.1 to 86.14.127.25486.14.127.25532,766
3086.14.128.0/1786.14.128.1 to 86.14.255.25486.14.255.25532,766
3186.15.0.0/1786.15.0.1 to 86.15.127.25486.15.127.25532,766
3286.15.128.0/1786.15.128.1 to 86.15.255.25486.15.255.25532,766
3386.16.0.0/1786.16.0.1 to 86.16.127.25486.16.127.25532,766
3486.16.128.0/1786.16.128.1 to 86.16.255.25486.16.255.25532,766
3586.17.0.0/1786.17.0.1 to 86.17.127.25486.17.127.25532,766
3686.17.128.0/1786.17.128.1 to 86.17.255.25486.17.255.25532,766
3786.18.0.0/1786.18.0.1 to 86.18.127.25486.18.127.25532,766
3886.18.128.0/1786.18.128.1 to 86.18.255.25486.18.255.25532,766
3986.19.0.0/1786.19.0.1 to 86.19.127.25486.19.127.25532,766
4086.19.128.0/1786.19.128.1 to 86.19.255.25486.19.255.25532,766
4186.20.0.0/1786.20.0.1 to 86.20.127.25486.20.127.25532,766
4286.20.128.0/1786.20.128.1 to 86.20.255.25486.20.255.25532,766
4386.21.0.0/1786.21.0.1 to 86.21.127.25486.21.127.25532,766
4486.21.128.0/1786.21.128.1 to 86.21.255.25486.21.255.25532,766
4586.22.0.0/1786.22.0.1 to 86.22.127.25486.22.127.25532,766
4686.22.128.0/1786.22.128.1 to 86.22.255.25486.22.255.25532,766
4786.23.0.0/1786.23.0.1 to 86.23.127.25486.23.127.25532,766
4886.23.128.0/1786.23.128.1 to 86.23.255.25486.23.255.25532,766
4986.24.0.0/1786.24.0.1 to 86.24.127.25486.24.127.25532,766
5086.24.128.0/1786.24.128.1 to 86.24.255.25486.24.255.25532,766
5186.25.0.0/1786.25.0.1 to 86.25.127.25486.25.127.25532,766
5286.25.128.0/1786.25.128.1 to 86.25.255.25486.25.255.25532,766
5386.26.0.0/1786.26.0.1 to 86.26.127.25486.26.127.25532,766
5486.26.128.0/1786.26.128.1 to 86.26.255.25486.26.255.25532,766
5586.27.0.0/1786.27.0.1 to 86.27.127.25486.27.127.25532,766
5686.27.128.0/1786.27.128.1 to 86.27.255.25486.27.255.25532,766
5786.28.0.0/1786.28.0.1 to 86.28.127.25486.28.127.25532,766
5886.28.128.0/1786.28.128.1 to 86.28.255.25486.28.255.25532,766
5986.29.0.0/1786.29.0.1 to 86.29.127.25486.29.127.25532,766
6086.29.128.0/1786.29.128.1 to 86.29.255.25486.29.255.25532,766
6186.30.0.0/1786.30.0.1 to 86.30.127.25486.30.127.25532,766
6286.30.128.0/1786.30.128.1 to 86.30.255.25486.30.255.25532,766
6386.31.0.0/1786.31.0.1 to 86.31.127.25486.31.127.25532,766
6486.31.128.0/1786.31.128.1 to 86.31.255.25486.31.255.25532,766
6586.32.0.0/1786.32.0.1 to 86.32.127.25486.32.127.25532,766
6686.32.128.0/1786.32.128.1 to 86.32.255.25486.32.255.25532,766
6786.33.0.0/1786.33.0.1 to 86.33.127.25486.33.127.25532,766
6886.33.128.0/1786.33.128.1 to 86.33.255.25486.33.255.25532,766
6986.34.0.0/1786.34.0.1 to 86.34.127.25486.34.127.25532,766
7086.34.128.0/1786.34.128.1 to 86.34.255.25486.34.255.25532,766
7186.35.0.0/1786.35.0.1 to 86.35.127.25486.35.127.25532,766
7286.35.128.0/1786.35.128.1 to 86.35.255.25486.35.255.25532,766
7386.36.0.0/1786.36.0.1 to 86.36.127.25486.36.127.25532,766
7486.36.128.0/1786.36.128.1 to 86.36.255.25486.36.255.25532,766
7586.37.0.0/1786.37.0.1 to 86.37.127.25486.37.127.25532,766
7686.37.128.0/1786.37.128.1 to 86.37.255.25486.37.255.25532,766
7786.38.0.0/1786.38.0.1 to 86.38.127.25486.38.127.25532,766
7886.38.128.0/1786.38.128.1 to 86.38.255.25486.38.255.25532,766
7986.39.0.0/1786.39.0.1 to 86.39.127.25486.39.127.25532,766
8086.39.128.0/1786.39.128.1 to 86.39.255.25486.39.255.25532,766
8186.40.0.0/1786.40.0.1 to 86.40.127.25486.40.127.25532,766
8286.40.128.0/1786.40.128.1 to 86.40.255.25486.40.255.25532,766
8386.41.0.0/1786.41.0.1 to 86.41.127.25486.41.127.25532,766
8486.41.128.0/1786.41.128.1 to 86.41.255.25486.41.255.25532,766
8586.42.0.0/1786.42.0.1 to 86.42.127.25486.42.127.25532,766
8686.42.128.0/1786.42.128.1 to 86.42.255.25486.42.255.25532,766
8786.43.0.0/1786.43.0.1 to 86.43.127.25486.43.127.25532,766
8886.43.128.0/1786.43.128.1 to 86.43.255.25486.43.255.25532,766
8986.44.0.0/1786.44.0.1 to 86.44.127.25486.44.127.25532,766
9086.44.128.0/1786.44.128.1 to 86.44.255.25486.44.255.25532,766
9186.45.0.0/1786.45.0.1 to 86.45.127.25486.45.127.25532,766
9286.45.128.0/1786.45.128.1 to 86.45.255.25486.45.255.25532,766
9386.46.0.0/1786.46.0.1 to 86.46.127.25486.46.127.25532,766
9486.46.128.0/1786.46.128.1 to 86.46.255.25486.46.255.25532,766
9586.47.0.0/1786.47.0.1 to 86.47.127.25486.47.127.25532,766
9686.47.128.0/1786.47.128.1 to 86.47.255.25486.47.255.25532,766
9786.48.0.0/1786.48.0.1 to 86.48.127.25486.48.127.25532,766
9886.48.128.0/1786.48.128.1 to 86.48.255.25486.48.255.25532,766
9986.49.0.0/1786.49.0.1 to 86.49.127.25486.49.127.25532,766
10086.49.128.0/1786.49.128.1 to 86.49.255.25486.49.255.25532,766
10186.50.0.0/1786.50.0.1 to 86.50.127.25486.50.127.25532,766
10286.50.128.0/1786.50.128.1 to 86.50.255.25486.50.255.25532,766
10386.51.0.0/1786.51.0.1 to 86.51.127.25486.51.127.25532,766
10486.51.128.0/1786.51.128.1 to 86.51.255.25486.51.255.25532,766
10586.52.0.0/1786.52.0.1 to 86.52.127.25486.52.127.25532,766
10686.52.128.0/1786.52.128.1 to 86.52.255.25486.52.255.25532,766
10786.53.0.0/1786.53.0.1 to 86.53.127.25486.53.127.25532,766
10886.53.128.0/1786.53.128.1 to 86.53.255.25486.53.255.25532,766
10986.54.0.0/1786.54.0.1 to 86.54.127.25486.54.127.25532,766
11086.54.128.0/1786.54.128.1 to 86.54.255.25486.54.255.25532,766
11186.55.0.0/1786.55.0.1 to 86.55.127.25486.55.127.25532,766
11286.55.128.0/1786.55.128.1 to 86.55.255.25486.55.255.25532,766
11386.56.0.0/1786.56.0.1 to 86.56.127.25486.56.127.25532,766
11486.56.128.0/1786.56.128.1 to 86.56.255.25486.56.255.25532,766
11586.57.0.0/1786.57.0.1 to 86.57.127.25486.57.127.25532,766
11686.57.128.0/1786.57.128.1 to 86.57.255.25486.57.255.25532,766
11786.58.0.0/1786.58.0.1 to 86.58.127.25486.58.127.25532,766
11886.58.128.0/1786.58.128.1 to 86.58.255.25486.58.255.25532,766
11986.59.0.0/1786.59.0.1 to 86.59.127.25486.59.127.25532,766
12086.59.128.0/1786.59.128.1 to 86.59.255.25486.59.255.25532,766
12186.60.0.0/1786.60.0.1 to 86.60.127.25486.60.127.25532,766
12286.60.128.0/1786.60.128.1 to 86.60.255.25486.60.255.25532,766
12386.61.0.0/1786.61.0.1 to 86.61.127.25486.61.127.25532,766
12486.61.128.0/1786.61.128.1 to 86.61.255.25486.61.255.25532,766
12586.62.0.0/1786.62.0.1 to 86.62.127.25486.62.127.25532,766
12686.62.128.0/1786.62.128.1 to 86.62.255.25486.62.255.25532,766
12786.63.0.0/1786.63.0.1 to 86.63.127.25486.63.127.25532,766
12886.63.128.0/1786.63.128.1 to 86.63.255.25486.63.255.25532,766
12986.64.0.0/1786.64.0.1 to 86.64.127.25486.64.127.25532,766
13086.64.128.0/1786.64.128.1 to 86.64.255.25486.64.255.25532,766
13186.65.0.0/1786.65.0.1 to 86.65.127.25486.65.127.25532,766
13286.65.128.0/1786.65.128.1 to 86.65.255.25486.65.255.25532,766
13386.66.0.0/1786.66.0.1 to 86.66.127.25486.66.127.25532,766
13486.66.128.0/1786.66.128.1 to 86.66.255.25486.66.255.25532,766
13586.67.0.0/1786.67.0.1 to 86.67.127.25486.67.127.25532,766
13686.67.128.0/1786.67.128.1 to 86.67.255.25486.67.255.25532,766
13786.68.0.0/1786.68.0.1 to 86.68.127.25486.68.127.25532,766
13886.68.128.0/1786.68.128.1 to 86.68.255.25486.68.255.25532,766
13986.69.0.0/1786.69.0.1 to 86.69.127.25486.69.127.25532,766
14086.69.128.0/1786.69.128.1 to 86.69.255.25486.69.255.25532,766
14186.70.0.0/1786.70.0.1 to 86.70.127.25486.70.127.25532,766
14286.70.128.0/1786.70.128.1 to 86.70.255.25486.70.255.25532,766
14386.71.0.0/1786.71.0.1 to 86.71.127.25486.71.127.25532,766
14486.71.128.0/1786.71.128.1 to 86.71.255.25486.71.255.25532,766
14586.72.0.0/1786.72.0.1 to 86.72.127.25486.72.127.25532,766
14686.72.128.0/1786.72.128.1 to 86.72.255.25486.72.255.25532,766
14786.73.0.0/1786.73.0.1 to 86.73.127.25486.73.127.25532,766
14886.73.128.0/1786.73.128.1 to 86.73.255.25486.73.255.25532,766
14986.74.0.0/1786.74.0.1 to 86.74.127.25486.74.127.25532,766
15086.74.128.0/1786.74.128.1 to 86.74.255.25486.74.255.25532,766
15186.75.0.0/1786.75.0.1 to 86.75.127.25486.75.127.25532,766
15286.75.128.0/1786.75.128.1 to 86.75.255.25486.75.255.25532,766
15386.76.0.0/1786.76.0.1 to 86.76.127.25486.76.127.25532,766
15486.76.128.0/1786.76.128.1 to 86.76.255.25486.76.255.25532,766
15586.77.0.0/1786.77.0.1 to 86.77.127.25486.77.127.25532,766
15686.77.128.0/1786.77.128.1 to 86.77.255.25486.77.255.25532,766
15786.78.0.0/1786.78.0.1 to 86.78.127.25486.78.127.25532,766
15886.78.128.0/1786.78.128.1 to 86.78.255.25486.78.255.25532,766
15986.79.0.0/1786.79.0.1 to 86.79.127.25486.79.127.25532,766
16086.79.128.0/1786.79.128.1 to 86.79.255.25486.79.255.25532,766
16186.80.0.0/1786.80.0.1 to 86.80.127.25486.80.127.25532,766
16286.80.128.0/1786.80.128.1 to 86.80.255.25486.80.255.25532,766
16386.81.0.0/1786.81.0.1 to 86.81.127.25486.81.127.25532,766
16486.81.128.0/1786.81.128.1 to 86.81.255.25486.81.255.25532,766
16586.82.0.0/1786.82.0.1 to 86.82.127.25486.82.127.25532,766
16686.82.128.0/1786.82.128.1 to 86.82.255.25486.82.255.25532,766
16786.83.0.0/1786.83.0.1 to 86.83.127.25486.83.127.25532,766
16886.83.128.0/1786.83.128.1 to 86.83.255.25486.83.255.25532,766
16986.84.0.0/1786.84.0.1 to 86.84.127.25486.84.127.25532,766
17086.84.128.0/1786.84.128.1 to 86.84.255.25486.84.255.25532,766
17186.85.0.0/1786.85.0.1 to 86.85.127.25486.85.127.25532,766
17286.85.128.0/1786.85.128.1 to 86.85.255.25486.85.255.25532,766
17386.86.0.0/1786.86.0.1 to 86.86.127.25486.86.127.25532,766
17486.86.128.0/1786.86.128.1 to 86.86.255.25486.86.255.25532,766
17586.87.0.0/1786.87.0.1 to 86.87.127.25486.87.127.25532,766
17686.87.128.0/1786.87.128.1 to 86.87.255.25486.87.255.25532,766
17786.88.0.0/1786.88.0.1 to 86.88.127.25486.88.127.25532,766
17886.88.128.0/1786.88.128.1 to 86.88.255.25486.88.255.25532,766
17986.89.0.0/1786.89.0.1 to 86.89.127.25486.89.127.25532,766
18086.89.128.0/1786.89.128.1 to 86.89.255.25486.89.255.25532,766
18186.90.0.0/1786.90.0.1 to 86.90.127.25486.90.127.25532,766
18286.90.128.0/1786.90.128.1 to 86.90.255.25486.90.255.25532,766
18386.91.0.0/1786.91.0.1 to 86.91.127.25486.91.127.25532,766
18486.91.128.0/1786.91.128.1 to 86.91.255.25486.91.255.25532,766
18586.92.0.0/1786.92.0.1 to 86.92.127.25486.92.127.25532,766
18686.92.128.0/1786.92.128.1 to 86.92.255.25486.92.255.25532,766
18786.93.0.0/1786.93.0.1 to 86.93.127.25486.93.127.25532,766
18886.93.128.0/1786.93.128.1 to 86.93.255.25486.93.255.25532,766
18986.94.0.0/1786.94.0.1 to 86.94.127.25486.94.127.25532,766
19086.94.128.0/1786.94.128.1 to 86.94.255.25486.94.255.25532,766
19186.95.0.0/1786.95.0.1 to 86.95.127.25486.95.127.25532,766
19286.95.128.0/1786.95.128.1 to 86.95.255.25486.95.255.25532,766
19386.96.0.0/1786.96.0.1 to 86.96.127.25486.96.127.25532,766
19486.96.128.0/1786.96.128.1 to 86.96.255.25486.96.255.25532,766
19586.97.0.0/1786.97.0.1 to 86.97.127.25486.97.127.25532,766
19686.97.128.0/1786.97.128.1 to 86.97.255.25486.97.255.25532,766
19786.98.0.0/1786.98.0.1 to 86.98.127.25486.98.127.25532,766
19886.98.128.0/1786.98.128.1 to 86.98.255.25486.98.255.25532,766
19986.99.0.0/1786.99.0.1 to 86.99.127.25486.99.127.25532,766
20086.99.128.0/1786.99.128.1 to 86.99.255.25486.99.255.25532,766
20186.100.0.0/1786.100.0.1 to 86.100.127.25486.100.127.25532,766
20286.100.128.0/1786.100.128.1 to 86.100.255.25486.100.255.25532,766
20386.101.0.0/1786.101.0.1 to 86.101.127.25486.101.127.25532,766
20486.101.128.0/1786.101.128.1 to 86.101.255.25486.101.255.25532,766
20586.102.0.0/1786.102.0.1 to 86.102.127.25486.102.127.25532,766
20686.102.128.0/1786.102.128.1 to 86.102.255.25486.102.255.25532,766
20786.103.0.0/1786.103.0.1 to 86.103.127.25486.103.127.25532,766
20886.103.128.0/1786.103.128.1 to 86.103.255.25486.103.255.25532,766
20986.104.0.0/1786.104.0.1 to 86.104.127.25486.104.127.25532,766
21086.104.128.0/1786.104.128.1 to 86.104.255.25486.104.255.25532,766
21186.105.0.0/1786.105.0.1 to 86.105.127.25486.105.127.25532,766
21286.105.128.0/1786.105.128.1 to 86.105.255.25486.105.255.25532,766
21386.106.0.0/1786.106.0.1 to 86.106.127.25486.106.127.25532,766
21486.106.128.0/1786.106.128.1 to 86.106.255.25486.106.255.25532,766
21586.107.0.0/1786.107.0.1 to 86.107.127.25486.107.127.25532,766
21686.107.128.0/1786.107.128.1 to 86.107.255.25486.107.255.25532,766
21786.108.0.0/1786.108.0.1 to 86.108.127.25486.108.127.25532,766
21886.108.128.0/1786.108.128.1 to 86.108.255.25486.108.255.25532,766
21986.109.0.0/1786.109.0.1 to 86.109.127.25486.109.127.25532,766
22086.109.128.0/1786.109.128.1 to 86.109.255.25486.109.255.25532,766
22186.110.0.0/1786.110.0.1 to 86.110.127.25486.110.127.25532,766
22286.110.128.0/1786.110.128.1 to 86.110.255.25486.110.255.25532,766
22386.111.0.0/1786.111.0.1 to 86.111.127.25486.111.127.25532,766
22486.111.128.0/1786.111.128.1 to 86.111.255.25486.111.255.25532,766
22586.112.0.0/1786.112.0.1 to 86.112.127.25486.112.127.25532,766
22686.112.128.0/1786.112.128.1 to 86.112.255.25486.112.255.25532,766
22786.113.0.0/1786.113.0.1 to 86.113.127.25486.113.127.25532,766
22886.113.128.0/1786.113.128.1 to 86.113.255.25486.113.255.25532,766
22986.114.0.0/1786.114.0.1 to 86.114.127.25486.114.127.25532,766
23086.114.128.0/1786.114.128.1 to 86.114.255.25486.114.255.25532,766
23186.115.0.0/1786.115.0.1 to 86.115.127.25486.115.127.25532,766
23286.115.128.0/1786.115.128.1 to 86.115.255.25486.115.255.25532,766
23386.116.0.0/1786.116.0.1 to 86.116.127.25486.116.127.25532,766
23486.116.128.0/1786.116.128.1 to 86.116.255.25486.116.255.25532,766
23586.117.0.0/1786.117.0.1 to 86.117.127.25486.117.127.25532,766
23686.117.128.0/1786.117.128.1 to 86.117.255.25486.117.255.25532,766
23786.118.0.0/1786.118.0.1 to 86.118.127.25486.118.127.25532,766
23886.118.128.0/1786.118.128.1 to 86.118.255.25486.118.255.25532,766
23986.119.0.0/1786.119.0.1 to 86.119.127.25486.119.127.25532,766
24086.119.128.0/1786.119.128.1 to 86.119.255.25486.119.255.25532,766
24186.120.0.0/1786.120.0.1 to 86.120.127.25486.120.127.25532,766
24286.120.128.0/1786.120.128.1 to 86.120.255.25486.120.255.25532,766
24386.121.0.0/1786.121.0.1 to 86.121.127.25486.121.127.25532,766
24486.121.128.0/1786.121.128.1 to 86.121.255.25486.121.255.25532,766
24586.122.0.0/1786.122.0.1 to 86.122.127.25486.122.127.25532,766
24686.122.128.0/1786.122.128.1 to 86.122.255.25486.122.255.25532,766
24786.123.0.0/1786.123.0.1 to 86.123.127.25486.123.127.25532,766
24886.123.128.0/1786.123.128.1 to 86.123.255.25486.123.255.25532,766
24986.124.0.0/1786.124.0.1 to 86.124.127.25486.124.127.25532,766
25086.124.128.0/1786.124.128.1 to 86.124.255.25486.124.255.25532,766
25186.125.0.0/1786.125.0.1 to 86.125.127.25486.125.127.25532,766
25286.125.128.0/1786.125.128.1 to 86.125.255.25486.125.255.25532,766
25386.126.0.0/1786.126.0.1 to 86.126.127.25486.126.127.25532,766
25486.126.128.0/1786.126.128.1 to 86.126.255.25486.126.255.25532,766
25586.127.0.0/1786.127.0.1 to 86.127.127.25486.127.127.25532,766
25686.127.128.0/1786.127.128.1 to 86.127.255.25486.127.255.25532,766

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.