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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.

Network88.0.0.0/6
Usable hosts67,108,862
Subnet mask252.0.0.0
Addresses67,108,864
Network address
88.0.0.0
Broadcast address
91.255.255.255
First usable
88.0.0.1
Last usable
91.255.255.254
Usable hosts
67,108,862 (67,108,864 less the network and broadcast addresses)
Subnet mask
252.0.0.0
Wildcard mask
3.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/6
Type
Public public
Old class
A (default /8)
As numbers
Hex 58000000 · Integer 1476395008 to 1543503871
Reverse DNS zones
88.in-addr.arpa
89.in-addr.arpa
90.in-addr.arpa
91.in-addr.arpa
/6 is not on a 8-bit boundary, so it takes 4 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011000.00000000.00000000.0000000088.0.0.0
Subnet mask11111100.00000000.00000000.00000000252.0.0.0
Network01011000.00000000.00000000.0000000088.0.0.0
Broadcast01011011.11111111.11111111.1111111191.255.255.255
Split into smaller subnets/18
/7 (2)/8 (4)/9 (8)/10 (16)/11 (32)/12 (64)/13 (128)/14 (256)/15 (512)/16 (1,024)/17 (2,048)/18 (4,096)

88.0.0.0/6 makes 4,096 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
188.0.0.0/1888.0.0.1 to 88.0.63.25488.0.63.25516,382
288.0.64.0/1888.0.64.1 to 88.0.127.25488.0.127.25516,382
388.0.128.0/1888.0.128.1 to 88.0.191.25488.0.191.25516,382
488.0.192.0/1888.0.192.1 to 88.0.255.25488.0.255.25516,382
588.1.0.0/1888.1.0.1 to 88.1.63.25488.1.63.25516,382
688.1.64.0/1888.1.64.1 to 88.1.127.25488.1.127.25516,382
788.1.128.0/1888.1.128.1 to 88.1.191.25488.1.191.25516,382
888.1.192.0/1888.1.192.1 to 88.1.255.25488.1.255.25516,382
988.2.0.0/1888.2.0.1 to 88.2.63.25488.2.63.25516,382
1088.2.64.0/1888.2.64.1 to 88.2.127.25488.2.127.25516,382
1188.2.128.0/1888.2.128.1 to 88.2.191.25488.2.191.25516,382
1288.2.192.0/1888.2.192.1 to 88.2.255.25488.2.255.25516,382
1388.3.0.0/1888.3.0.1 to 88.3.63.25488.3.63.25516,382
1488.3.64.0/1888.3.64.1 to 88.3.127.25488.3.127.25516,382
1588.3.128.0/1888.3.128.1 to 88.3.191.25488.3.191.25516,382
1688.3.192.0/1888.3.192.1 to 88.3.255.25488.3.255.25516,382
1788.4.0.0/1888.4.0.1 to 88.4.63.25488.4.63.25516,382
1888.4.64.0/1888.4.64.1 to 88.4.127.25488.4.127.25516,382
1988.4.128.0/1888.4.128.1 to 88.4.191.25488.4.191.25516,382
2088.4.192.0/1888.4.192.1 to 88.4.255.25488.4.255.25516,382
2188.5.0.0/1888.5.0.1 to 88.5.63.25488.5.63.25516,382
2288.5.64.0/1888.5.64.1 to 88.5.127.25488.5.127.25516,382
2388.5.128.0/1888.5.128.1 to 88.5.191.25488.5.191.25516,382
2488.5.192.0/1888.5.192.1 to 88.5.255.25488.5.255.25516,382
2588.6.0.0/1888.6.0.1 to 88.6.63.25488.6.63.25516,382
2688.6.64.0/1888.6.64.1 to 88.6.127.25488.6.127.25516,382
2788.6.128.0/1888.6.128.1 to 88.6.191.25488.6.191.25516,382
2888.6.192.0/1888.6.192.1 to 88.6.255.25488.6.255.25516,382
2988.7.0.0/1888.7.0.1 to 88.7.63.25488.7.63.25516,382
3088.7.64.0/1888.7.64.1 to 88.7.127.25488.7.127.25516,382
3188.7.128.0/1888.7.128.1 to 88.7.191.25488.7.191.25516,382
3288.7.192.0/1888.7.192.1 to 88.7.255.25488.7.255.25516,382
3388.8.0.0/1888.8.0.1 to 88.8.63.25488.8.63.25516,382
3488.8.64.0/1888.8.64.1 to 88.8.127.25488.8.127.25516,382
3588.8.128.0/1888.8.128.1 to 88.8.191.25488.8.191.25516,382
3688.8.192.0/1888.8.192.1 to 88.8.255.25488.8.255.25516,382
3788.9.0.0/1888.9.0.1 to 88.9.63.25488.9.63.25516,382
3888.9.64.0/1888.9.64.1 to 88.9.127.25488.9.127.25516,382
3988.9.128.0/1888.9.128.1 to 88.9.191.25488.9.191.25516,382
4088.9.192.0/1888.9.192.1 to 88.9.255.25488.9.255.25516,382
4188.10.0.0/1888.10.0.1 to 88.10.63.25488.10.63.25516,382
4288.10.64.0/1888.10.64.1 to 88.10.127.25488.10.127.25516,382
4388.10.128.0/1888.10.128.1 to 88.10.191.25488.10.191.25516,382
4488.10.192.0/1888.10.192.1 to 88.10.255.25488.10.255.25516,382
4588.11.0.0/1888.11.0.1 to 88.11.63.25488.11.63.25516,382
4688.11.64.0/1888.11.64.1 to 88.11.127.25488.11.127.25516,382
4788.11.128.0/1888.11.128.1 to 88.11.191.25488.11.191.25516,382
4888.11.192.0/1888.11.192.1 to 88.11.255.25488.11.255.25516,382
4988.12.0.0/1888.12.0.1 to 88.12.63.25488.12.63.25516,382
5088.12.64.0/1888.12.64.1 to 88.12.127.25488.12.127.25516,382
5188.12.128.0/1888.12.128.1 to 88.12.191.25488.12.191.25516,382
5288.12.192.0/1888.12.192.1 to 88.12.255.25488.12.255.25516,382
5388.13.0.0/1888.13.0.1 to 88.13.63.25488.13.63.25516,382
5488.13.64.0/1888.13.64.1 to 88.13.127.25488.13.127.25516,382
5588.13.128.0/1888.13.128.1 to 88.13.191.25488.13.191.25516,382
5688.13.192.0/1888.13.192.1 to 88.13.255.25488.13.255.25516,382
5788.14.0.0/1888.14.0.1 to 88.14.63.25488.14.63.25516,382
5888.14.64.0/1888.14.64.1 to 88.14.127.25488.14.127.25516,382
5988.14.128.0/1888.14.128.1 to 88.14.191.25488.14.191.25516,382
6088.14.192.0/1888.14.192.1 to 88.14.255.25488.14.255.25516,382
6188.15.0.0/1888.15.0.1 to 88.15.63.25488.15.63.25516,382
6288.15.64.0/1888.15.64.1 to 88.15.127.25488.15.127.25516,382
6388.15.128.0/1888.15.128.1 to 88.15.191.25488.15.191.25516,382
6488.15.192.0/1888.15.192.1 to 88.15.255.25488.15.255.25516,382
6588.16.0.0/1888.16.0.1 to 88.16.63.25488.16.63.25516,382
6688.16.64.0/1888.16.64.1 to 88.16.127.25488.16.127.25516,382
6788.16.128.0/1888.16.128.1 to 88.16.191.25488.16.191.25516,382
6888.16.192.0/1888.16.192.1 to 88.16.255.25488.16.255.25516,382
6988.17.0.0/1888.17.0.1 to 88.17.63.25488.17.63.25516,382
7088.17.64.0/1888.17.64.1 to 88.17.127.25488.17.127.25516,382
7188.17.128.0/1888.17.128.1 to 88.17.191.25488.17.191.25516,382
7288.17.192.0/1888.17.192.1 to 88.17.255.25488.17.255.25516,382
7388.18.0.0/1888.18.0.1 to 88.18.63.25488.18.63.25516,382
7488.18.64.0/1888.18.64.1 to 88.18.127.25488.18.127.25516,382
7588.18.128.0/1888.18.128.1 to 88.18.191.25488.18.191.25516,382
7688.18.192.0/1888.18.192.1 to 88.18.255.25488.18.255.25516,382
7788.19.0.0/1888.19.0.1 to 88.19.63.25488.19.63.25516,382
7888.19.64.0/1888.19.64.1 to 88.19.127.25488.19.127.25516,382
7988.19.128.0/1888.19.128.1 to 88.19.191.25488.19.191.25516,382
8088.19.192.0/1888.19.192.1 to 88.19.255.25488.19.255.25516,382
8188.20.0.0/1888.20.0.1 to 88.20.63.25488.20.63.25516,382
8288.20.64.0/1888.20.64.1 to 88.20.127.25488.20.127.25516,382
8388.20.128.0/1888.20.128.1 to 88.20.191.25488.20.191.25516,382
8488.20.192.0/1888.20.192.1 to 88.20.255.25488.20.255.25516,382
8588.21.0.0/1888.21.0.1 to 88.21.63.25488.21.63.25516,382
8688.21.64.0/1888.21.64.1 to 88.21.127.25488.21.127.25516,382
8788.21.128.0/1888.21.128.1 to 88.21.191.25488.21.191.25516,382
8888.21.192.0/1888.21.192.1 to 88.21.255.25488.21.255.25516,382
8988.22.0.0/1888.22.0.1 to 88.22.63.25488.22.63.25516,382
9088.22.64.0/1888.22.64.1 to 88.22.127.25488.22.127.25516,382
9188.22.128.0/1888.22.128.1 to 88.22.191.25488.22.191.25516,382
9288.22.192.0/1888.22.192.1 to 88.22.255.25488.22.255.25516,382
9388.23.0.0/1888.23.0.1 to 88.23.63.25488.23.63.25516,382
9488.23.64.0/1888.23.64.1 to 88.23.127.25488.23.127.25516,382
9588.23.128.0/1888.23.128.1 to 88.23.191.25488.23.191.25516,382
9688.23.192.0/1888.23.192.1 to 88.23.255.25488.23.255.25516,382
9788.24.0.0/1888.24.0.1 to 88.24.63.25488.24.63.25516,382
9888.24.64.0/1888.24.64.1 to 88.24.127.25488.24.127.25516,382
9988.24.128.0/1888.24.128.1 to 88.24.191.25488.24.191.25516,382
10088.24.192.0/1888.24.192.1 to 88.24.255.25488.24.255.25516,382
10188.25.0.0/1888.25.0.1 to 88.25.63.25488.25.63.25516,382
10288.25.64.0/1888.25.64.1 to 88.25.127.25488.25.127.25516,382
10388.25.128.0/1888.25.128.1 to 88.25.191.25488.25.191.25516,382
10488.25.192.0/1888.25.192.1 to 88.25.255.25488.25.255.25516,382
10588.26.0.0/1888.26.0.1 to 88.26.63.25488.26.63.25516,382
10688.26.64.0/1888.26.64.1 to 88.26.127.25488.26.127.25516,382
10788.26.128.0/1888.26.128.1 to 88.26.191.25488.26.191.25516,382
10888.26.192.0/1888.26.192.1 to 88.26.255.25488.26.255.25516,382
10988.27.0.0/1888.27.0.1 to 88.27.63.25488.27.63.25516,382
11088.27.64.0/1888.27.64.1 to 88.27.127.25488.27.127.25516,382
11188.27.128.0/1888.27.128.1 to 88.27.191.25488.27.191.25516,382
11288.27.192.0/1888.27.192.1 to 88.27.255.25488.27.255.25516,382
11388.28.0.0/1888.28.0.1 to 88.28.63.25488.28.63.25516,382
11488.28.64.0/1888.28.64.1 to 88.28.127.25488.28.127.25516,382
11588.28.128.0/1888.28.128.1 to 88.28.191.25488.28.191.25516,382
11688.28.192.0/1888.28.192.1 to 88.28.255.25488.28.255.25516,382
11788.29.0.0/1888.29.0.1 to 88.29.63.25488.29.63.25516,382
11888.29.64.0/1888.29.64.1 to 88.29.127.25488.29.127.25516,382
11988.29.128.0/1888.29.128.1 to 88.29.191.25488.29.191.25516,382
12088.29.192.0/1888.29.192.1 to 88.29.255.25488.29.255.25516,382
12188.30.0.0/1888.30.0.1 to 88.30.63.25488.30.63.25516,382
12288.30.64.0/1888.30.64.1 to 88.30.127.25488.30.127.25516,382
12388.30.128.0/1888.30.128.1 to 88.30.191.25488.30.191.25516,382
12488.30.192.0/1888.30.192.1 to 88.30.255.25488.30.255.25516,382
12588.31.0.0/1888.31.0.1 to 88.31.63.25488.31.63.25516,382
12688.31.64.0/1888.31.64.1 to 88.31.127.25488.31.127.25516,382
12788.31.128.0/1888.31.128.1 to 88.31.191.25488.31.191.25516,382
12888.31.192.0/1888.31.192.1 to 88.31.255.25488.31.255.25516,382
12988.32.0.0/1888.32.0.1 to 88.32.63.25488.32.63.25516,382
13088.32.64.0/1888.32.64.1 to 88.32.127.25488.32.127.25516,382
13188.32.128.0/1888.32.128.1 to 88.32.191.25488.32.191.25516,382
13288.32.192.0/1888.32.192.1 to 88.32.255.25488.32.255.25516,382
13388.33.0.0/1888.33.0.1 to 88.33.63.25488.33.63.25516,382
13488.33.64.0/1888.33.64.1 to 88.33.127.25488.33.127.25516,382
13588.33.128.0/1888.33.128.1 to 88.33.191.25488.33.191.25516,382
13688.33.192.0/1888.33.192.1 to 88.33.255.25488.33.255.25516,382
13788.34.0.0/1888.34.0.1 to 88.34.63.25488.34.63.25516,382
13888.34.64.0/1888.34.64.1 to 88.34.127.25488.34.127.25516,382
13988.34.128.0/1888.34.128.1 to 88.34.191.25488.34.191.25516,382
14088.34.192.0/1888.34.192.1 to 88.34.255.25488.34.255.25516,382
14188.35.0.0/1888.35.0.1 to 88.35.63.25488.35.63.25516,382
14288.35.64.0/1888.35.64.1 to 88.35.127.25488.35.127.25516,382
14388.35.128.0/1888.35.128.1 to 88.35.191.25488.35.191.25516,382
14488.35.192.0/1888.35.192.1 to 88.35.255.25488.35.255.25516,382
14588.36.0.0/1888.36.0.1 to 88.36.63.25488.36.63.25516,382
14688.36.64.0/1888.36.64.1 to 88.36.127.25488.36.127.25516,382
14788.36.128.0/1888.36.128.1 to 88.36.191.25488.36.191.25516,382
14888.36.192.0/1888.36.192.1 to 88.36.255.25488.36.255.25516,382
14988.37.0.0/1888.37.0.1 to 88.37.63.25488.37.63.25516,382
15088.37.64.0/1888.37.64.1 to 88.37.127.25488.37.127.25516,382
15188.37.128.0/1888.37.128.1 to 88.37.191.25488.37.191.25516,382
15288.37.192.0/1888.37.192.1 to 88.37.255.25488.37.255.25516,382
15388.38.0.0/1888.38.0.1 to 88.38.63.25488.38.63.25516,382
15488.38.64.0/1888.38.64.1 to 88.38.127.25488.38.127.25516,382
15588.38.128.0/1888.38.128.1 to 88.38.191.25488.38.191.25516,382
15688.38.192.0/1888.38.192.1 to 88.38.255.25488.38.255.25516,382
15788.39.0.0/1888.39.0.1 to 88.39.63.25488.39.63.25516,382
15888.39.64.0/1888.39.64.1 to 88.39.127.25488.39.127.25516,382
15988.39.128.0/1888.39.128.1 to 88.39.191.25488.39.191.25516,382
16088.39.192.0/1888.39.192.1 to 88.39.255.25488.39.255.25516,382
16188.40.0.0/1888.40.0.1 to 88.40.63.25488.40.63.25516,382
16288.40.64.0/1888.40.64.1 to 88.40.127.25488.40.127.25516,382
16388.40.128.0/1888.40.128.1 to 88.40.191.25488.40.191.25516,382
16488.40.192.0/1888.40.192.1 to 88.40.255.25488.40.255.25516,382
16588.41.0.0/1888.41.0.1 to 88.41.63.25488.41.63.25516,382
16688.41.64.0/1888.41.64.1 to 88.41.127.25488.41.127.25516,382
16788.41.128.0/1888.41.128.1 to 88.41.191.25488.41.191.25516,382
16888.41.192.0/1888.41.192.1 to 88.41.255.25488.41.255.25516,382
16988.42.0.0/1888.42.0.1 to 88.42.63.25488.42.63.25516,382
17088.42.64.0/1888.42.64.1 to 88.42.127.25488.42.127.25516,382
17188.42.128.0/1888.42.128.1 to 88.42.191.25488.42.191.25516,382
17288.42.192.0/1888.42.192.1 to 88.42.255.25488.42.255.25516,382
17388.43.0.0/1888.43.0.1 to 88.43.63.25488.43.63.25516,382
17488.43.64.0/1888.43.64.1 to 88.43.127.25488.43.127.25516,382
17588.43.128.0/1888.43.128.1 to 88.43.191.25488.43.191.25516,382
17688.43.192.0/1888.43.192.1 to 88.43.255.25488.43.255.25516,382
17788.44.0.0/1888.44.0.1 to 88.44.63.25488.44.63.25516,382
17888.44.64.0/1888.44.64.1 to 88.44.127.25488.44.127.25516,382
17988.44.128.0/1888.44.128.1 to 88.44.191.25488.44.191.25516,382
18088.44.192.0/1888.44.192.1 to 88.44.255.25488.44.255.25516,382
18188.45.0.0/1888.45.0.1 to 88.45.63.25488.45.63.25516,382
18288.45.64.0/1888.45.64.1 to 88.45.127.25488.45.127.25516,382
18388.45.128.0/1888.45.128.1 to 88.45.191.25488.45.191.25516,382
18488.45.192.0/1888.45.192.1 to 88.45.255.25488.45.255.25516,382
18588.46.0.0/1888.46.0.1 to 88.46.63.25488.46.63.25516,382
18688.46.64.0/1888.46.64.1 to 88.46.127.25488.46.127.25516,382
18788.46.128.0/1888.46.128.1 to 88.46.191.25488.46.191.25516,382
18888.46.192.0/1888.46.192.1 to 88.46.255.25488.46.255.25516,382
18988.47.0.0/1888.47.0.1 to 88.47.63.25488.47.63.25516,382
19088.47.64.0/1888.47.64.1 to 88.47.127.25488.47.127.25516,382
19188.47.128.0/1888.47.128.1 to 88.47.191.25488.47.191.25516,382
19288.47.192.0/1888.47.192.1 to 88.47.255.25488.47.255.25516,382
19388.48.0.0/1888.48.0.1 to 88.48.63.25488.48.63.25516,382
19488.48.64.0/1888.48.64.1 to 88.48.127.25488.48.127.25516,382
19588.48.128.0/1888.48.128.1 to 88.48.191.25488.48.191.25516,382
19688.48.192.0/1888.48.192.1 to 88.48.255.25488.48.255.25516,382
19788.49.0.0/1888.49.0.1 to 88.49.63.25488.49.63.25516,382
19888.49.64.0/1888.49.64.1 to 88.49.127.25488.49.127.25516,382
19988.49.128.0/1888.49.128.1 to 88.49.191.25488.49.191.25516,382
20088.49.192.0/1888.49.192.1 to 88.49.255.25488.49.255.25516,382
20188.50.0.0/1888.50.0.1 to 88.50.63.25488.50.63.25516,382
20288.50.64.0/1888.50.64.1 to 88.50.127.25488.50.127.25516,382
20388.50.128.0/1888.50.128.1 to 88.50.191.25488.50.191.25516,382
20488.50.192.0/1888.50.192.1 to 88.50.255.25488.50.255.25516,382
20588.51.0.0/1888.51.0.1 to 88.51.63.25488.51.63.25516,382
20688.51.64.0/1888.51.64.1 to 88.51.127.25488.51.127.25516,382
20788.51.128.0/1888.51.128.1 to 88.51.191.25488.51.191.25516,382
20888.51.192.0/1888.51.192.1 to 88.51.255.25488.51.255.25516,382
20988.52.0.0/1888.52.0.1 to 88.52.63.25488.52.63.25516,382
21088.52.64.0/1888.52.64.1 to 88.52.127.25488.52.127.25516,382
21188.52.128.0/1888.52.128.1 to 88.52.191.25488.52.191.25516,382
21288.52.192.0/1888.52.192.1 to 88.52.255.25488.52.255.25516,382
21388.53.0.0/1888.53.0.1 to 88.53.63.25488.53.63.25516,382
21488.53.64.0/1888.53.64.1 to 88.53.127.25488.53.127.25516,382
21588.53.128.0/1888.53.128.1 to 88.53.191.25488.53.191.25516,382
21688.53.192.0/1888.53.192.1 to 88.53.255.25488.53.255.25516,382
21788.54.0.0/1888.54.0.1 to 88.54.63.25488.54.63.25516,382
21888.54.64.0/1888.54.64.1 to 88.54.127.25488.54.127.25516,382
21988.54.128.0/1888.54.128.1 to 88.54.191.25488.54.191.25516,382
22088.54.192.0/1888.54.192.1 to 88.54.255.25488.54.255.25516,382
22188.55.0.0/1888.55.0.1 to 88.55.63.25488.55.63.25516,382
22288.55.64.0/1888.55.64.1 to 88.55.127.25488.55.127.25516,382
22388.55.128.0/1888.55.128.1 to 88.55.191.25488.55.191.25516,382
22488.55.192.0/1888.55.192.1 to 88.55.255.25488.55.255.25516,382
22588.56.0.0/1888.56.0.1 to 88.56.63.25488.56.63.25516,382
22688.56.64.0/1888.56.64.1 to 88.56.127.25488.56.127.25516,382
22788.56.128.0/1888.56.128.1 to 88.56.191.25488.56.191.25516,382
22888.56.192.0/1888.56.192.1 to 88.56.255.25488.56.255.25516,382
22988.57.0.0/1888.57.0.1 to 88.57.63.25488.57.63.25516,382
23088.57.64.0/1888.57.64.1 to 88.57.127.25488.57.127.25516,382
23188.57.128.0/1888.57.128.1 to 88.57.191.25488.57.191.25516,382
23288.57.192.0/1888.57.192.1 to 88.57.255.25488.57.255.25516,382
23388.58.0.0/1888.58.0.1 to 88.58.63.25488.58.63.25516,382
23488.58.64.0/1888.58.64.1 to 88.58.127.25488.58.127.25516,382
23588.58.128.0/1888.58.128.1 to 88.58.191.25488.58.191.25516,382
23688.58.192.0/1888.58.192.1 to 88.58.255.25488.58.255.25516,382
23788.59.0.0/1888.59.0.1 to 88.59.63.25488.59.63.25516,382
23888.59.64.0/1888.59.64.1 to 88.59.127.25488.59.127.25516,382
23988.59.128.0/1888.59.128.1 to 88.59.191.25488.59.191.25516,382
24088.59.192.0/1888.59.192.1 to 88.59.255.25488.59.255.25516,382
24188.60.0.0/1888.60.0.1 to 88.60.63.25488.60.63.25516,382
24288.60.64.0/1888.60.64.1 to 88.60.127.25488.60.127.25516,382
24388.60.128.0/1888.60.128.1 to 88.60.191.25488.60.191.25516,382
24488.60.192.0/1888.60.192.1 to 88.60.255.25488.60.255.25516,382
24588.61.0.0/1888.61.0.1 to 88.61.63.25488.61.63.25516,382
24688.61.64.0/1888.61.64.1 to 88.61.127.25488.61.127.25516,382
24788.61.128.0/1888.61.128.1 to 88.61.191.25488.61.191.25516,382
24888.61.192.0/1888.61.192.1 to 88.61.255.25488.61.255.25516,382
24988.62.0.0/1888.62.0.1 to 88.62.63.25488.62.63.25516,382
25088.62.64.0/1888.62.64.1 to 88.62.127.25488.62.127.25516,382
25188.62.128.0/1888.62.128.1 to 88.62.191.25488.62.191.25516,382
25288.62.192.0/1888.62.192.1 to 88.62.255.25488.62.255.25516,382
25388.63.0.0/1888.63.0.1 to 88.63.63.25488.63.63.25516,382
25488.63.64.0/1888.63.64.1 to 88.63.127.25488.63.127.25516,382
25588.63.128.0/1888.63.128.1 to 88.63.191.25488.63.191.25516,382
25688.63.192.0/1888.63.192.1 to 88.63.255.25488.63.255.25516,382

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.