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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.

Network88.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
88.0.0.0
Broadcast address
89.255.255.255
First usable
88.0.0.1
Last usable
89.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 58000000 · Integer 1476395008 to 1509949439
Reverse DNS zones
88.in-addr.arpa
89.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011000.00000000.00000000.0000000088.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network01011000.00000000.00000000.0000000088.0.0.0
Broadcast01011001.11111111.11111111.1111111189.255.255.255
Split into smaller subnets/19
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

88.0.0.0/7 makes 4,096 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
188.0.0.0/1988.0.0.1 to 88.0.31.25488.0.31.2558,190
288.0.32.0/1988.0.32.1 to 88.0.63.25488.0.63.2558,190
388.0.64.0/1988.0.64.1 to 88.0.95.25488.0.95.2558,190
488.0.96.0/1988.0.96.1 to 88.0.127.25488.0.127.2558,190
588.0.128.0/1988.0.128.1 to 88.0.159.25488.0.159.2558,190
688.0.160.0/1988.0.160.1 to 88.0.191.25488.0.191.2558,190
788.0.192.0/1988.0.192.1 to 88.0.223.25488.0.223.2558,190
888.0.224.0/1988.0.224.1 to 88.0.255.25488.0.255.2558,190
988.1.0.0/1988.1.0.1 to 88.1.31.25488.1.31.2558,190
1088.1.32.0/1988.1.32.1 to 88.1.63.25488.1.63.2558,190
1188.1.64.0/1988.1.64.1 to 88.1.95.25488.1.95.2558,190
1288.1.96.0/1988.1.96.1 to 88.1.127.25488.1.127.2558,190
1388.1.128.0/1988.1.128.1 to 88.1.159.25488.1.159.2558,190
1488.1.160.0/1988.1.160.1 to 88.1.191.25488.1.191.2558,190
1588.1.192.0/1988.1.192.1 to 88.1.223.25488.1.223.2558,190
1688.1.224.0/1988.1.224.1 to 88.1.255.25488.1.255.2558,190
1788.2.0.0/1988.2.0.1 to 88.2.31.25488.2.31.2558,190
1888.2.32.0/1988.2.32.1 to 88.2.63.25488.2.63.2558,190
1988.2.64.0/1988.2.64.1 to 88.2.95.25488.2.95.2558,190
2088.2.96.0/1988.2.96.1 to 88.2.127.25488.2.127.2558,190
2188.2.128.0/1988.2.128.1 to 88.2.159.25488.2.159.2558,190
2288.2.160.0/1988.2.160.1 to 88.2.191.25488.2.191.2558,190
2388.2.192.0/1988.2.192.1 to 88.2.223.25488.2.223.2558,190
2488.2.224.0/1988.2.224.1 to 88.2.255.25488.2.255.2558,190
2588.3.0.0/1988.3.0.1 to 88.3.31.25488.3.31.2558,190
2688.3.32.0/1988.3.32.1 to 88.3.63.25488.3.63.2558,190
2788.3.64.0/1988.3.64.1 to 88.3.95.25488.3.95.2558,190
2888.3.96.0/1988.3.96.1 to 88.3.127.25488.3.127.2558,190
2988.3.128.0/1988.3.128.1 to 88.3.159.25488.3.159.2558,190
3088.3.160.0/1988.3.160.1 to 88.3.191.25488.3.191.2558,190
3188.3.192.0/1988.3.192.1 to 88.3.223.25488.3.223.2558,190
3288.3.224.0/1988.3.224.1 to 88.3.255.25488.3.255.2558,190
3388.4.0.0/1988.4.0.1 to 88.4.31.25488.4.31.2558,190
3488.4.32.0/1988.4.32.1 to 88.4.63.25488.4.63.2558,190
3588.4.64.0/1988.4.64.1 to 88.4.95.25488.4.95.2558,190
3688.4.96.0/1988.4.96.1 to 88.4.127.25488.4.127.2558,190
3788.4.128.0/1988.4.128.1 to 88.4.159.25488.4.159.2558,190
3888.4.160.0/1988.4.160.1 to 88.4.191.25488.4.191.2558,190
3988.4.192.0/1988.4.192.1 to 88.4.223.25488.4.223.2558,190
4088.4.224.0/1988.4.224.1 to 88.4.255.25488.4.255.2558,190
4188.5.0.0/1988.5.0.1 to 88.5.31.25488.5.31.2558,190
4288.5.32.0/1988.5.32.1 to 88.5.63.25488.5.63.2558,190
4388.5.64.0/1988.5.64.1 to 88.5.95.25488.5.95.2558,190
4488.5.96.0/1988.5.96.1 to 88.5.127.25488.5.127.2558,190
4588.5.128.0/1988.5.128.1 to 88.5.159.25488.5.159.2558,190
4688.5.160.0/1988.5.160.1 to 88.5.191.25488.5.191.2558,190
4788.5.192.0/1988.5.192.1 to 88.5.223.25488.5.223.2558,190
4888.5.224.0/1988.5.224.1 to 88.5.255.25488.5.255.2558,190
4988.6.0.0/1988.6.0.1 to 88.6.31.25488.6.31.2558,190
5088.6.32.0/1988.6.32.1 to 88.6.63.25488.6.63.2558,190
5188.6.64.0/1988.6.64.1 to 88.6.95.25488.6.95.2558,190
5288.6.96.0/1988.6.96.1 to 88.6.127.25488.6.127.2558,190
5388.6.128.0/1988.6.128.1 to 88.6.159.25488.6.159.2558,190
5488.6.160.0/1988.6.160.1 to 88.6.191.25488.6.191.2558,190
5588.6.192.0/1988.6.192.1 to 88.6.223.25488.6.223.2558,190
5688.6.224.0/1988.6.224.1 to 88.6.255.25488.6.255.2558,190
5788.7.0.0/1988.7.0.1 to 88.7.31.25488.7.31.2558,190
5888.7.32.0/1988.7.32.1 to 88.7.63.25488.7.63.2558,190
5988.7.64.0/1988.7.64.1 to 88.7.95.25488.7.95.2558,190
6088.7.96.0/1988.7.96.1 to 88.7.127.25488.7.127.2558,190
6188.7.128.0/1988.7.128.1 to 88.7.159.25488.7.159.2558,190
6288.7.160.0/1988.7.160.1 to 88.7.191.25488.7.191.2558,190
6388.7.192.0/1988.7.192.1 to 88.7.223.25488.7.223.2558,190
6488.7.224.0/1988.7.224.1 to 88.7.255.25488.7.255.2558,190
6588.8.0.0/1988.8.0.1 to 88.8.31.25488.8.31.2558,190
6688.8.32.0/1988.8.32.1 to 88.8.63.25488.8.63.2558,190
6788.8.64.0/1988.8.64.1 to 88.8.95.25488.8.95.2558,190
6888.8.96.0/1988.8.96.1 to 88.8.127.25488.8.127.2558,190
6988.8.128.0/1988.8.128.1 to 88.8.159.25488.8.159.2558,190
7088.8.160.0/1988.8.160.1 to 88.8.191.25488.8.191.2558,190
7188.8.192.0/1988.8.192.1 to 88.8.223.25488.8.223.2558,190
7288.8.224.0/1988.8.224.1 to 88.8.255.25488.8.255.2558,190
7388.9.0.0/1988.9.0.1 to 88.9.31.25488.9.31.2558,190
7488.9.32.0/1988.9.32.1 to 88.9.63.25488.9.63.2558,190
7588.9.64.0/1988.9.64.1 to 88.9.95.25488.9.95.2558,190
7688.9.96.0/1988.9.96.1 to 88.9.127.25488.9.127.2558,190
7788.9.128.0/1988.9.128.1 to 88.9.159.25488.9.159.2558,190
7888.9.160.0/1988.9.160.1 to 88.9.191.25488.9.191.2558,190
7988.9.192.0/1988.9.192.1 to 88.9.223.25488.9.223.2558,190
8088.9.224.0/1988.9.224.1 to 88.9.255.25488.9.255.2558,190
8188.10.0.0/1988.10.0.1 to 88.10.31.25488.10.31.2558,190
8288.10.32.0/1988.10.32.1 to 88.10.63.25488.10.63.2558,190
8388.10.64.0/1988.10.64.1 to 88.10.95.25488.10.95.2558,190
8488.10.96.0/1988.10.96.1 to 88.10.127.25488.10.127.2558,190
8588.10.128.0/1988.10.128.1 to 88.10.159.25488.10.159.2558,190
8688.10.160.0/1988.10.160.1 to 88.10.191.25488.10.191.2558,190
8788.10.192.0/1988.10.192.1 to 88.10.223.25488.10.223.2558,190
8888.10.224.0/1988.10.224.1 to 88.10.255.25488.10.255.2558,190
8988.11.0.0/1988.11.0.1 to 88.11.31.25488.11.31.2558,190
9088.11.32.0/1988.11.32.1 to 88.11.63.25488.11.63.2558,190
9188.11.64.0/1988.11.64.1 to 88.11.95.25488.11.95.2558,190
9288.11.96.0/1988.11.96.1 to 88.11.127.25488.11.127.2558,190
9388.11.128.0/1988.11.128.1 to 88.11.159.25488.11.159.2558,190
9488.11.160.0/1988.11.160.1 to 88.11.191.25488.11.191.2558,190
9588.11.192.0/1988.11.192.1 to 88.11.223.25488.11.223.2558,190
9688.11.224.0/1988.11.224.1 to 88.11.255.25488.11.255.2558,190
9788.12.0.0/1988.12.0.1 to 88.12.31.25488.12.31.2558,190
9888.12.32.0/1988.12.32.1 to 88.12.63.25488.12.63.2558,190
9988.12.64.0/1988.12.64.1 to 88.12.95.25488.12.95.2558,190
10088.12.96.0/1988.12.96.1 to 88.12.127.25488.12.127.2558,190
10188.12.128.0/1988.12.128.1 to 88.12.159.25488.12.159.2558,190
10288.12.160.0/1988.12.160.1 to 88.12.191.25488.12.191.2558,190
10388.12.192.0/1988.12.192.1 to 88.12.223.25488.12.223.2558,190
10488.12.224.0/1988.12.224.1 to 88.12.255.25488.12.255.2558,190
10588.13.0.0/1988.13.0.1 to 88.13.31.25488.13.31.2558,190
10688.13.32.0/1988.13.32.1 to 88.13.63.25488.13.63.2558,190
10788.13.64.0/1988.13.64.1 to 88.13.95.25488.13.95.2558,190
10888.13.96.0/1988.13.96.1 to 88.13.127.25488.13.127.2558,190
10988.13.128.0/1988.13.128.1 to 88.13.159.25488.13.159.2558,190
11088.13.160.0/1988.13.160.1 to 88.13.191.25488.13.191.2558,190
11188.13.192.0/1988.13.192.1 to 88.13.223.25488.13.223.2558,190
11288.13.224.0/1988.13.224.1 to 88.13.255.25488.13.255.2558,190
11388.14.0.0/1988.14.0.1 to 88.14.31.25488.14.31.2558,190
11488.14.32.0/1988.14.32.1 to 88.14.63.25488.14.63.2558,190
11588.14.64.0/1988.14.64.1 to 88.14.95.25488.14.95.2558,190
11688.14.96.0/1988.14.96.1 to 88.14.127.25488.14.127.2558,190
11788.14.128.0/1988.14.128.1 to 88.14.159.25488.14.159.2558,190
11888.14.160.0/1988.14.160.1 to 88.14.191.25488.14.191.2558,190
11988.14.192.0/1988.14.192.1 to 88.14.223.25488.14.223.2558,190
12088.14.224.0/1988.14.224.1 to 88.14.255.25488.14.255.2558,190
12188.15.0.0/1988.15.0.1 to 88.15.31.25488.15.31.2558,190
12288.15.32.0/1988.15.32.1 to 88.15.63.25488.15.63.2558,190
12388.15.64.0/1988.15.64.1 to 88.15.95.25488.15.95.2558,190
12488.15.96.0/1988.15.96.1 to 88.15.127.25488.15.127.2558,190
12588.15.128.0/1988.15.128.1 to 88.15.159.25488.15.159.2558,190
12688.15.160.0/1988.15.160.1 to 88.15.191.25488.15.191.2558,190
12788.15.192.0/1988.15.192.1 to 88.15.223.25488.15.223.2558,190
12888.15.224.0/1988.15.224.1 to 88.15.255.25488.15.255.2558,190
12988.16.0.0/1988.16.0.1 to 88.16.31.25488.16.31.2558,190
13088.16.32.0/1988.16.32.1 to 88.16.63.25488.16.63.2558,190
13188.16.64.0/1988.16.64.1 to 88.16.95.25488.16.95.2558,190
13288.16.96.0/1988.16.96.1 to 88.16.127.25488.16.127.2558,190
13388.16.128.0/1988.16.128.1 to 88.16.159.25488.16.159.2558,190
13488.16.160.0/1988.16.160.1 to 88.16.191.25488.16.191.2558,190
13588.16.192.0/1988.16.192.1 to 88.16.223.25488.16.223.2558,190
13688.16.224.0/1988.16.224.1 to 88.16.255.25488.16.255.2558,190
13788.17.0.0/1988.17.0.1 to 88.17.31.25488.17.31.2558,190
13888.17.32.0/1988.17.32.1 to 88.17.63.25488.17.63.2558,190
13988.17.64.0/1988.17.64.1 to 88.17.95.25488.17.95.2558,190
14088.17.96.0/1988.17.96.1 to 88.17.127.25488.17.127.2558,190
14188.17.128.0/1988.17.128.1 to 88.17.159.25488.17.159.2558,190
14288.17.160.0/1988.17.160.1 to 88.17.191.25488.17.191.2558,190
14388.17.192.0/1988.17.192.1 to 88.17.223.25488.17.223.2558,190
14488.17.224.0/1988.17.224.1 to 88.17.255.25488.17.255.2558,190
14588.18.0.0/1988.18.0.1 to 88.18.31.25488.18.31.2558,190
14688.18.32.0/1988.18.32.1 to 88.18.63.25488.18.63.2558,190
14788.18.64.0/1988.18.64.1 to 88.18.95.25488.18.95.2558,190
14888.18.96.0/1988.18.96.1 to 88.18.127.25488.18.127.2558,190
14988.18.128.0/1988.18.128.1 to 88.18.159.25488.18.159.2558,190
15088.18.160.0/1988.18.160.1 to 88.18.191.25488.18.191.2558,190
15188.18.192.0/1988.18.192.1 to 88.18.223.25488.18.223.2558,190
15288.18.224.0/1988.18.224.1 to 88.18.255.25488.18.255.2558,190
15388.19.0.0/1988.19.0.1 to 88.19.31.25488.19.31.2558,190
15488.19.32.0/1988.19.32.1 to 88.19.63.25488.19.63.2558,190
15588.19.64.0/1988.19.64.1 to 88.19.95.25488.19.95.2558,190
15688.19.96.0/1988.19.96.1 to 88.19.127.25488.19.127.2558,190
15788.19.128.0/1988.19.128.1 to 88.19.159.25488.19.159.2558,190
15888.19.160.0/1988.19.160.1 to 88.19.191.25488.19.191.2558,190
15988.19.192.0/1988.19.192.1 to 88.19.223.25488.19.223.2558,190
16088.19.224.0/1988.19.224.1 to 88.19.255.25488.19.255.2558,190
16188.20.0.0/1988.20.0.1 to 88.20.31.25488.20.31.2558,190
16288.20.32.0/1988.20.32.1 to 88.20.63.25488.20.63.2558,190
16388.20.64.0/1988.20.64.1 to 88.20.95.25488.20.95.2558,190
16488.20.96.0/1988.20.96.1 to 88.20.127.25488.20.127.2558,190
16588.20.128.0/1988.20.128.1 to 88.20.159.25488.20.159.2558,190
16688.20.160.0/1988.20.160.1 to 88.20.191.25488.20.191.2558,190
16788.20.192.0/1988.20.192.1 to 88.20.223.25488.20.223.2558,190
16888.20.224.0/1988.20.224.1 to 88.20.255.25488.20.255.2558,190
16988.21.0.0/1988.21.0.1 to 88.21.31.25488.21.31.2558,190
17088.21.32.0/1988.21.32.1 to 88.21.63.25488.21.63.2558,190
17188.21.64.0/1988.21.64.1 to 88.21.95.25488.21.95.2558,190
17288.21.96.0/1988.21.96.1 to 88.21.127.25488.21.127.2558,190
17388.21.128.0/1988.21.128.1 to 88.21.159.25488.21.159.2558,190
17488.21.160.0/1988.21.160.1 to 88.21.191.25488.21.191.2558,190
17588.21.192.0/1988.21.192.1 to 88.21.223.25488.21.223.2558,190
17688.21.224.0/1988.21.224.1 to 88.21.255.25488.21.255.2558,190
17788.22.0.0/1988.22.0.1 to 88.22.31.25488.22.31.2558,190
17888.22.32.0/1988.22.32.1 to 88.22.63.25488.22.63.2558,190
17988.22.64.0/1988.22.64.1 to 88.22.95.25488.22.95.2558,190
18088.22.96.0/1988.22.96.1 to 88.22.127.25488.22.127.2558,190
18188.22.128.0/1988.22.128.1 to 88.22.159.25488.22.159.2558,190
18288.22.160.0/1988.22.160.1 to 88.22.191.25488.22.191.2558,190
18388.22.192.0/1988.22.192.1 to 88.22.223.25488.22.223.2558,190
18488.22.224.0/1988.22.224.1 to 88.22.255.25488.22.255.2558,190
18588.23.0.0/1988.23.0.1 to 88.23.31.25488.23.31.2558,190
18688.23.32.0/1988.23.32.1 to 88.23.63.25488.23.63.2558,190
18788.23.64.0/1988.23.64.1 to 88.23.95.25488.23.95.2558,190
18888.23.96.0/1988.23.96.1 to 88.23.127.25488.23.127.2558,190
18988.23.128.0/1988.23.128.1 to 88.23.159.25488.23.159.2558,190
19088.23.160.0/1988.23.160.1 to 88.23.191.25488.23.191.2558,190
19188.23.192.0/1988.23.192.1 to 88.23.223.25488.23.223.2558,190
19288.23.224.0/1988.23.224.1 to 88.23.255.25488.23.255.2558,190
19388.24.0.0/1988.24.0.1 to 88.24.31.25488.24.31.2558,190
19488.24.32.0/1988.24.32.1 to 88.24.63.25488.24.63.2558,190
19588.24.64.0/1988.24.64.1 to 88.24.95.25488.24.95.2558,190
19688.24.96.0/1988.24.96.1 to 88.24.127.25488.24.127.2558,190
19788.24.128.0/1988.24.128.1 to 88.24.159.25488.24.159.2558,190
19888.24.160.0/1988.24.160.1 to 88.24.191.25488.24.191.2558,190
19988.24.192.0/1988.24.192.1 to 88.24.223.25488.24.223.2558,190
20088.24.224.0/1988.24.224.1 to 88.24.255.25488.24.255.2558,190
20188.25.0.0/1988.25.0.1 to 88.25.31.25488.25.31.2558,190
20288.25.32.0/1988.25.32.1 to 88.25.63.25488.25.63.2558,190
20388.25.64.0/1988.25.64.1 to 88.25.95.25488.25.95.2558,190
20488.25.96.0/1988.25.96.1 to 88.25.127.25488.25.127.2558,190
20588.25.128.0/1988.25.128.1 to 88.25.159.25488.25.159.2558,190
20688.25.160.0/1988.25.160.1 to 88.25.191.25488.25.191.2558,190
20788.25.192.0/1988.25.192.1 to 88.25.223.25488.25.223.2558,190
20888.25.224.0/1988.25.224.1 to 88.25.255.25488.25.255.2558,190
20988.26.0.0/1988.26.0.1 to 88.26.31.25488.26.31.2558,190
21088.26.32.0/1988.26.32.1 to 88.26.63.25488.26.63.2558,190
21188.26.64.0/1988.26.64.1 to 88.26.95.25488.26.95.2558,190
21288.26.96.0/1988.26.96.1 to 88.26.127.25488.26.127.2558,190
21388.26.128.0/1988.26.128.1 to 88.26.159.25488.26.159.2558,190
21488.26.160.0/1988.26.160.1 to 88.26.191.25488.26.191.2558,190
21588.26.192.0/1988.26.192.1 to 88.26.223.25488.26.223.2558,190
21688.26.224.0/1988.26.224.1 to 88.26.255.25488.26.255.2558,190
21788.27.0.0/1988.27.0.1 to 88.27.31.25488.27.31.2558,190
21888.27.32.0/1988.27.32.1 to 88.27.63.25488.27.63.2558,190
21988.27.64.0/1988.27.64.1 to 88.27.95.25488.27.95.2558,190
22088.27.96.0/1988.27.96.1 to 88.27.127.25488.27.127.2558,190
22188.27.128.0/1988.27.128.1 to 88.27.159.25488.27.159.2558,190
22288.27.160.0/1988.27.160.1 to 88.27.191.25488.27.191.2558,190
22388.27.192.0/1988.27.192.1 to 88.27.223.25488.27.223.2558,190
22488.27.224.0/1988.27.224.1 to 88.27.255.25488.27.255.2558,190
22588.28.0.0/1988.28.0.1 to 88.28.31.25488.28.31.2558,190
22688.28.32.0/1988.28.32.1 to 88.28.63.25488.28.63.2558,190
22788.28.64.0/1988.28.64.1 to 88.28.95.25488.28.95.2558,190
22888.28.96.0/1988.28.96.1 to 88.28.127.25488.28.127.2558,190
22988.28.128.0/1988.28.128.1 to 88.28.159.25488.28.159.2558,190
23088.28.160.0/1988.28.160.1 to 88.28.191.25488.28.191.2558,190
23188.28.192.0/1988.28.192.1 to 88.28.223.25488.28.223.2558,190
23288.28.224.0/1988.28.224.1 to 88.28.255.25488.28.255.2558,190
23388.29.0.0/1988.29.0.1 to 88.29.31.25488.29.31.2558,190
23488.29.32.0/1988.29.32.1 to 88.29.63.25488.29.63.2558,190
23588.29.64.0/1988.29.64.1 to 88.29.95.25488.29.95.2558,190
23688.29.96.0/1988.29.96.1 to 88.29.127.25488.29.127.2558,190
23788.29.128.0/1988.29.128.1 to 88.29.159.25488.29.159.2558,190
23888.29.160.0/1988.29.160.1 to 88.29.191.25488.29.191.2558,190
23988.29.192.0/1988.29.192.1 to 88.29.223.25488.29.223.2558,190
24088.29.224.0/1988.29.224.1 to 88.29.255.25488.29.255.2558,190
24188.30.0.0/1988.30.0.1 to 88.30.31.25488.30.31.2558,190
24288.30.32.0/1988.30.32.1 to 88.30.63.25488.30.63.2558,190
24388.30.64.0/1988.30.64.1 to 88.30.95.25488.30.95.2558,190
24488.30.96.0/1988.30.96.1 to 88.30.127.25488.30.127.2558,190
24588.30.128.0/1988.30.128.1 to 88.30.159.25488.30.159.2558,190
24688.30.160.0/1988.30.160.1 to 88.30.191.25488.30.191.2558,190
24788.30.192.0/1988.30.192.1 to 88.30.223.25488.30.223.2558,190
24888.30.224.0/1988.30.224.1 to 88.30.255.25488.30.255.2558,190
24988.31.0.0/1988.31.0.1 to 88.31.31.25488.31.31.2558,190
25088.31.32.0/1988.31.32.1 to 88.31.63.25488.31.63.2558,190
25188.31.64.0/1988.31.64.1 to 88.31.95.25488.31.95.2558,190
25288.31.96.0/1988.31.96.1 to 88.31.127.25488.31.127.2558,190
25388.31.128.0/1988.31.128.1 to 88.31.159.25488.31.159.2558,190
25488.31.160.0/1988.31.160.1 to 88.31.191.25488.31.191.2558,190
25588.31.192.0/1988.31.192.1 to 88.31.223.25488.31.223.2558,190
25688.31.224.0/1988.31.224.1 to 88.31.255.25488.31.255.2558,190

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.