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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.

Network84.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
84.0.0.0
Broadcast address
84.255.255.255
First usable
84.0.0.1
Last usable
84.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 54000000 · Integer 1409286144 to 1426063359
Reverse DNS zone
84.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010100..00000000.00000000.0000000084.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01010100..00000000.00000000.0000000084.0.0.0
Broadcast01010100..11111111.11111111.1111111184.255.255.255
Split into smaller subnets/19
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

84.0.0.0/8 makes 2,048 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
184.0.0.0/1984.0.0.1 to 84.0.31.25484.0.31.2558,190
284.0.32.0/1984.0.32.1 to 84.0.63.25484.0.63.2558,190
384.0.64.0/1984.0.64.1 to 84.0.95.25484.0.95.2558,190
484.0.96.0/1984.0.96.1 to 84.0.127.25484.0.127.2558,190
584.0.128.0/1984.0.128.1 to 84.0.159.25484.0.159.2558,190
684.0.160.0/1984.0.160.1 to 84.0.191.25484.0.191.2558,190
784.0.192.0/1984.0.192.1 to 84.0.223.25484.0.223.2558,190
884.0.224.0/1984.0.224.1 to 84.0.255.25484.0.255.2558,190
984.1.0.0/1984.1.0.1 to 84.1.31.25484.1.31.2558,190
1084.1.32.0/1984.1.32.1 to 84.1.63.25484.1.63.2558,190
1184.1.64.0/1984.1.64.1 to 84.1.95.25484.1.95.2558,190
1284.1.96.0/1984.1.96.1 to 84.1.127.25484.1.127.2558,190
1384.1.128.0/1984.1.128.1 to 84.1.159.25484.1.159.2558,190
1484.1.160.0/1984.1.160.1 to 84.1.191.25484.1.191.2558,190
1584.1.192.0/1984.1.192.1 to 84.1.223.25484.1.223.2558,190
1684.1.224.0/1984.1.224.1 to 84.1.255.25484.1.255.2558,190
1784.2.0.0/1984.2.0.1 to 84.2.31.25484.2.31.2558,190
1884.2.32.0/1984.2.32.1 to 84.2.63.25484.2.63.2558,190
1984.2.64.0/1984.2.64.1 to 84.2.95.25484.2.95.2558,190
2084.2.96.0/1984.2.96.1 to 84.2.127.25484.2.127.2558,190
2184.2.128.0/1984.2.128.1 to 84.2.159.25484.2.159.2558,190
2284.2.160.0/1984.2.160.1 to 84.2.191.25484.2.191.2558,190
2384.2.192.0/1984.2.192.1 to 84.2.223.25484.2.223.2558,190
2484.2.224.0/1984.2.224.1 to 84.2.255.25484.2.255.2558,190
2584.3.0.0/1984.3.0.1 to 84.3.31.25484.3.31.2558,190
2684.3.32.0/1984.3.32.1 to 84.3.63.25484.3.63.2558,190
2784.3.64.0/1984.3.64.1 to 84.3.95.25484.3.95.2558,190
2884.3.96.0/1984.3.96.1 to 84.3.127.25484.3.127.2558,190
2984.3.128.0/1984.3.128.1 to 84.3.159.25484.3.159.2558,190
3084.3.160.0/1984.3.160.1 to 84.3.191.25484.3.191.2558,190
3184.3.192.0/1984.3.192.1 to 84.3.223.25484.3.223.2558,190
3284.3.224.0/1984.3.224.1 to 84.3.255.25484.3.255.2558,190
3384.4.0.0/1984.4.0.1 to 84.4.31.25484.4.31.2558,190
3484.4.32.0/1984.4.32.1 to 84.4.63.25484.4.63.2558,190
3584.4.64.0/1984.4.64.1 to 84.4.95.25484.4.95.2558,190
3684.4.96.0/1984.4.96.1 to 84.4.127.25484.4.127.2558,190
3784.4.128.0/1984.4.128.1 to 84.4.159.25484.4.159.2558,190
3884.4.160.0/1984.4.160.1 to 84.4.191.25484.4.191.2558,190
3984.4.192.0/1984.4.192.1 to 84.4.223.25484.4.223.2558,190
4084.4.224.0/1984.4.224.1 to 84.4.255.25484.4.255.2558,190
4184.5.0.0/1984.5.0.1 to 84.5.31.25484.5.31.2558,190
4284.5.32.0/1984.5.32.1 to 84.5.63.25484.5.63.2558,190
4384.5.64.0/1984.5.64.1 to 84.5.95.25484.5.95.2558,190
4484.5.96.0/1984.5.96.1 to 84.5.127.25484.5.127.2558,190
4584.5.128.0/1984.5.128.1 to 84.5.159.25484.5.159.2558,190
4684.5.160.0/1984.5.160.1 to 84.5.191.25484.5.191.2558,190
4784.5.192.0/1984.5.192.1 to 84.5.223.25484.5.223.2558,190
4884.5.224.0/1984.5.224.1 to 84.5.255.25484.5.255.2558,190
4984.6.0.0/1984.6.0.1 to 84.6.31.25484.6.31.2558,190
5084.6.32.0/1984.6.32.1 to 84.6.63.25484.6.63.2558,190
5184.6.64.0/1984.6.64.1 to 84.6.95.25484.6.95.2558,190
5284.6.96.0/1984.6.96.1 to 84.6.127.25484.6.127.2558,190
5384.6.128.0/1984.6.128.1 to 84.6.159.25484.6.159.2558,190
5484.6.160.0/1984.6.160.1 to 84.6.191.25484.6.191.2558,190
5584.6.192.0/1984.6.192.1 to 84.6.223.25484.6.223.2558,190
5684.6.224.0/1984.6.224.1 to 84.6.255.25484.6.255.2558,190
5784.7.0.0/1984.7.0.1 to 84.7.31.25484.7.31.2558,190
5884.7.32.0/1984.7.32.1 to 84.7.63.25484.7.63.2558,190
5984.7.64.0/1984.7.64.1 to 84.7.95.25484.7.95.2558,190
6084.7.96.0/1984.7.96.1 to 84.7.127.25484.7.127.2558,190
6184.7.128.0/1984.7.128.1 to 84.7.159.25484.7.159.2558,190
6284.7.160.0/1984.7.160.1 to 84.7.191.25484.7.191.2558,190
6384.7.192.0/1984.7.192.1 to 84.7.223.25484.7.223.2558,190
6484.7.224.0/1984.7.224.1 to 84.7.255.25484.7.255.2558,190
6584.8.0.0/1984.8.0.1 to 84.8.31.25484.8.31.2558,190
6684.8.32.0/1984.8.32.1 to 84.8.63.25484.8.63.2558,190
6784.8.64.0/1984.8.64.1 to 84.8.95.25484.8.95.2558,190
6884.8.96.0/1984.8.96.1 to 84.8.127.25484.8.127.2558,190
6984.8.128.0/1984.8.128.1 to 84.8.159.25484.8.159.2558,190
7084.8.160.0/1984.8.160.1 to 84.8.191.25484.8.191.2558,190
7184.8.192.0/1984.8.192.1 to 84.8.223.25484.8.223.2558,190
7284.8.224.0/1984.8.224.1 to 84.8.255.25484.8.255.2558,190
7384.9.0.0/1984.9.0.1 to 84.9.31.25484.9.31.2558,190
7484.9.32.0/1984.9.32.1 to 84.9.63.25484.9.63.2558,190
7584.9.64.0/1984.9.64.1 to 84.9.95.25484.9.95.2558,190
7684.9.96.0/1984.9.96.1 to 84.9.127.25484.9.127.2558,190
7784.9.128.0/1984.9.128.1 to 84.9.159.25484.9.159.2558,190
7884.9.160.0/1984.9.160.1 to 84.9.191.25484.9.191.2558,190
7984.9.192.0/1984.9.192.1 to 84.9.223.25484.9.223.2558,190
8084.9.224.0/1984.9.224.1 to 84.9.255.25484.9.255.2558,190
8184.10.0.0/1984.10.0.1 to 84.10.31.25484.10.31.2558,190
8284.10.32.0/1984.10.32.1 to 84.10.63.25484.10.63.2558,190
8384.10.64.0/1984.10.64.1 to 84.10.95.25484.10.95.2558,190
8484.10.96.0/1984.10.96.1 to 84.10.127.25484.10.127.2558,190
8584.10.128.0/1984.10.128.1 to 84.10.159.25484.10.159.2558,190
8684.10.160.0/1984.10.160.1 to 84.10.191.25484.10.191.2558,190
8784.10.192.0/1984.10.192.1 to 84.10.223.25484.10.223.2558,190
8884.10.224.0/1984.10.224.1 to 84.10.255.25484.10.255.2558,190
8984.11.0.0/1984.11.0.1 to 84.11.31.25484.11.31.2558,190
9084.11.32.0/1984.11.32.1 to 84.11.63.25484.11.63.2558,190
9184.11.64.0/1984.11.64.1 to 84.11.95.25484.11.95.2558,190
9284.11.96.0/1984.11.96.1 to 84.11.127.25484.11.127.2558,190
9384.11.128.0/1984.11.128.1 to 84.11.159.25484.11.159.2558,190
9484.11.160.0/1984.11.160.1 to 84.11.191.25484.11.191.2558,190
9584.11.192.0/1984.11.192.1 to 84.11.223.25484.11.223.2558,190
9684.11.224.0/1984.11.224.1 to 84.11.255.25484.11.255.2558,190
9784.12.0.0/1984.12.0.1 to 84.12.31.25484.12.31.2558,190
9884.12.32.0/1984.12.32.1 to 84.12.63.25484.12.63.2558,190
9984.12.64.0/1984.12.64.1 to 84.12.95.25484.12.95.2558,190
10084.12.96.0/1984.12.96.1 to 84.12.127.25484.12.127.2558,190
10184.12.128.0/1984.12.128.1 to 84.12.159.25484.12.159.2558,190
10284.12.160.0/1984.12.160.1 to 84.12.191.25484.12.191.2558,190
10384.12.192.0/1984.12.192.1 to 84.12.223.25484.12.223.2558,190
10484.12.224.0/1984.12.224.1 to 84.12.255.25484.12.255.2558,190
10584.13.0.0/1984.13.0.1 to 84.13.31.25484.13.31.2558,190
10684.13.32.0/1984.13.32.1 to 84.13.63.25484.13.63.2558,190
10784.13.64.0/1984.13.64.1 to 84.13.95.25484.13.95.2558,190
10884.13.96.0/1984.13.96.1 to 84.13.127.25484.13.127.2558,190
10984.13.128.0/1984.13.128.1 to 84.13.159.25484.13.159.2558,190
11084.13.160.0/1984.13.160.1 to 84.13.191.25484.13.191.2558,190
11184.13.192.0/1984.13.192.1 to 84.13.223.25484.13.223.2558,190
11284.13.224.0/1984.13.224.1 to 84.13.255.25484.13.255.2558,190
11384.14.0.0/1984.14.0.1 to 84.14.31.25484.14.31.2558,190
11484.14.32.0/1984.14.32.1 to 84.14.63.25484.14.63.2558,190
11584.14.64.0/1984.14.64.1 to 84.14.95.25484.14.95.2558,190
11684.14.96.0/1984.14.96.1 to 84.14.127.25484.14.127.2558,190
11784.14.128.0/1984.14.128.1 to 84.14.159.25484.14.159.2558,190
11884.14.160.0/1984.14.160.1 to 84.14.191.25484.14.191.2558,190
11984.14.192.0/1984.14.192.1 to 84.14.223.25484.14.223.2558,190
12084.14.224.0/1984.14.224.1 to 84.14.255.25484.14.255.2558,190
12184.15.0.0/1984.15.0.1 to 84.15.31.25484.15.31.2558,190
12284.15.32.0/1984.15.32.1 to 84.15.63.25484.15.63.2558,190
12384.15.64.0/1984.15.64.1 to 84.15.95.25484.15.95.2558,190
12484.15.96.0/1984.15.96.1 to 84.15.127.25484.15.127.2558,190
12584.15.128.0/1984.15.128.1 to 84.15.159.25484.15.159.2558,190
12684.15.160.0/1984.15.160.1 to 84.15.191.25484.15.191.2558,190
12784.15.192.0/1984.15.192.1 to 84.15.223.25484.15.223.2558,190
12884.15.224.0/1984.15.224.1 to 84.15.255.25484.15.255.2558,190
12984.16.0.0/1984.16.0.1 to 84.16.31.25484.16.31.2558,190
13084.16.32.0/1984.16.32.1 to 84.16.63.25484.16.63.2558,190
13184.16.64.0/1984.16.64.1 to 84.16.95.25484.16.95.2558,190
13284.16.96.0/1984.16.96.1 to 84.16.127.25484.16.127.2558,190
13384.16.128.0/1984.16.128.1 to 84.16.159.25484.16.159.2558,190
13484.16.160.0/1984.16.160.1 to 84.16.191.25484.16.191.2558,190
13584.16.192.0/1984.16.192.1 to 84.16.223.25484.16.223.2558,190
13684.16.224.0/1984.16.224.1 to 84.16.255.25484.16.255.2558,190
13784.17.0.0/1984.17.0.1 to 84.17.31.25484.17.31.2558,190
13884.17.32.0/1984.17.32.1 to 84.17.63.25484.17.63.2558,190
13984.17.64.0/1984.17.64.1 to 84.17.95.25484.17.95.2558,190
14084.17.96.0/1984.17.96.1 to 84.17.127.25484.17.127.2558,190
14184.17.128.0/1984.17.128.1 to 84.17.159.25484.17.159.2558,190
14284.17.160.0/1984.17.160.1 to 84.17.191.25484.17.191.2558,190
14384.17.192.0/1984.17.192.1 to 84.17.223.25484.17.223.2558,190
14484.17.224.0/1984.17.224.1 to 84.17.255.25484.17.255.2558,190
14584.18.0.0/1984.18.0.1 to 84.18.31.25484.18.31.2558,190
14684.18.32.0/1984.18.32.1 to 84.18.63.25484.18.63.2558,190
14784.18.64.0/1984.18.64.1 to 84.18.95.25484.18.95.2558,190
14884.18.96.0/1984.18.96.1 to 84.18.127.25484.18.127.2558,190
14984.18.128.0/1984.18.128.1 to 84.18.159.25484.18.159.2558,190
15084.18.160.0/1984.18.160.1 to 84.18.191.25484.18.191.2558,190
15184.18.192.0/1984.18.192.1 to 84.18.223.25484.18.223.2558,190
15284.18.224.0/1984.18.224.1 to 84.18.255.25484.18.255.2558,190
15384.19.0.0/1984.19.0.1 to 84.19.31.25484.19.31.2558,190
15484.19.32.0/1984.19.32.1 to 84.19.63.25484.19.63.2558,190
15584.19.64.0/1984.19.64.1 to 84.19.95.25484.19.95.2558,190
15684.19.96.0/1984.19.96.1 to 84.19.127.25484.19.127.2558,190
15784.19.128.0/1984.19.128.1 to 84.19.159.25484.19.159.2558,190
15884.19.160.0/1984.19.160.1 to 84.19.191.25484.19.191.2558,190
15984.19.192.0/1984.19.192.1 to 84.19.223.25484.19.223.2558,190
16084.19.224.0/1984.19.224.1 to 84.19.255.25484.19.255.2558,190
16184.20.0.0/1984.20.0.1 to 84.20.31.25484.20.31.2558,190
16284.20.32.0/1984.20.32.1 to 84.20.63.25484.20.63.2558,190
16384.20.64.0/1984.20.64.1 to 84.20.95.25484.20.95.2558,190
16484.20.96.0/1984.20.96.1 to 84.20.127.25484.20.127.2558,190
16584.20.128.0/1984.20.128.1 to 84.20.159.25484.20.159.2558,190
16684.20.160.0/1984.20.160.1 to 84.20.191.25484.20.191.2558,190
16784.20.192.0/1984.20.192.1 to 84.20.223.25484.20.223.2558,190
16884.20.224.0/1984.20.224.1 to 84.20.255.25484.20.255.2558,190
16984.21.0.0/1984.21.0.1 to 84.21.31.25484.21.31.2558,190
17084.21.32.0/1984.21.32.1 to 84.21.63.25484.21.63.2558,190
17184.21.64.0/1984.21.64.1 to 84.21.95.25484.21.95.2558,190
17284.21.96.0/1984.21.96.1 to 84.21.127.25484.21.127.2558,190
17384.21.128.0/1984.21.128.1 to 84.21.159.25484.21.159.2558,190
17484.21.160.0/1984.21.160.1 to 84.21.191.25484.21.191.2558,190
17584.21.192.0/1984.21.192.1 to 84.21.223.25484.21.223.2558,190
17684.21.224.0/1984.21.224.1 to 84.21.255.25484.21.255.2558,190
17784.22.0.0/1984.22.0.1 to 84.22.31.25484.22.31.2558,190
17884.22.32.0/1984.22.32.1 to 84.22.63.25484.22.63.2558,190
17984.22.64.0/1984.22.64.1 to 84.22.95.25484.22.95.2558,190
18084.22.96.0/1984.22.96.1 to 84.22.127.25484.22.127.2558,190
18184.22.128.0/1984.22.128.1 to 84.22.159.25484.22.159.2558,190
18284.22.160.0/1984.22.160.1 to 84.22.191.25484.22.191.2558,190
18384.22.192.0/1984.22.192.1 to 84.22.223.25484.22.223.2558,190
18484.22.224.0/1984.22.224.1 to 84.22.255.25484.22.255.2558,190
18584.23.0.0/1984.23.0.1 to 84.23.31.25484.23.31.2558,190
18684.23.32.0/1984.23.32.1 to 84.23.63.25484.23.63.2558,190
18784.23.64.0/1984.23.64.1 to 84.23.95.25484.23.95.2558,190
18884.23.96.0/1984.23.96.1 to 84.23.127.25484.23.127.2558,190
18984.23.128.0/1984.23.128.1 to 84.23.159.25484.23.159.2558,190
19084.23.160.0/1984.23.160.1 to 84.23.191.25484.23.191.2558,190
19184.23.192.0/1984.23.192.1 to 84.23.223.25484.23.223.2558,190
19284.23.224.0/1984.23.224.1 to 84.23.255.25484.23.255.2558,190
19384.24.0.0/1984.24.0.1 to 84.24.31.25484.24.31.2558,190
19484.24.32.0/1984.24.32.1 to 84.24.63.25484.24.63.2558,190
19584.24.64.0/1984.24.64.1 to 84.24.95.25484.24.95.2558,190
19684.24.96.0/1984.24.96.1 to 84.24.127.25484.24.127.2558,190
19784.24.128.0/1984.24.128.1 to 84.24.159.25484.24.159.2558,190
19884.24.160.0/1984.24.160.1 to 84.24.191.25484.24.191.2558,190
19984.24.192.0/1984.24.192.1 to 84.24.223.25484.24.223.2558,190
20084.24.224.0/1984.24.224.1 to 84.24.255.25484.24.255.2558,190
20184.25.0.0/1984.25.0.1 to 84.25.31.25484.25.31.2558,190
20284.25.32.0/1984.25.32.1 to 84.25.63.25484.25.63.2558,190
20384.25.64.0/1984.25.64.1 to 84.25.95.25484.25.95.2558,190
20484.25.96.0/1984.25.96.1 to 84.25.127.25484.25.127.2558,190
20584.25.128.0/1984.25.128.1 to 84.25.159.25484.25.159.2558,190
20684.25.160.0/1984.25.160.1 to 84.25.191.25484.25.191.2558,190
20784.25.192.0/1984.25.192.1 to 84.25.223.25484.25.223.2558,190
20884.25.224.0/1984.25.224.1 to 84.25.255.25484.25.255.2558,190
20984.26.0.0/1984.26.0.1 to 84.26.31.25484.26.31.2558,190
21084.26.32.0/1984.26.32.1 to 84.26.63.25484.26.63.2558,190
21184.26.64.0/1984.26.64.1 to 84.26.95.25484.26.95.2558,190
21284.26.96.0/1984.26.96.1 to 84.26.127.25484.26.127.2558,190
21384.26.128.0/1984.26.128.1 to 84.26.159.25484.26.159.2558,190
21484.26.160.0/1984.26.160.1 to 84.26.191.25484.26.191.2558,190
21584.26.192.0/1984.26.192.1 to 84.26.223.25484.26.223.2558,190
21684.26.224.0/1984.26.224.1 to 84.26.255.25484.26.255.2558,190
21784.27.0.0/1984.27.0.1 to 84.27.31.25484.27.31.2558,190
21884.27.32.0/1984.27.32.1 to 84.27.63.25484.27.63.2558,190
21984.27.64.0/1984.27.64.1 to 84.27.95.25484.27.95.2558,190
22084.27.96.0/1984.27.96.1 to 84.27.127.25484.27.127.2558,190
22184.27.128.0/1984.27.128.1 to 84.27.159.25484.27.159.2558,190
22284.27.160.0/1984.27.160.1 to 84.27.191.25484.27.191.2558,190
22384.27.192.0/1984.27.192.1 to 84.27.223.25484.27.223.2558,190
22484.27.224.0/1984.27.224.1 to 84.27.255.25484.27.255.2558,190
22584.28.0.0/1984.28.0.1 to 84.28.31.25484.28.31.2558,190
22684.28.32.0/1984.28.32.1 to 84.28.63.25484.28.63.2558,190
22784.28.64.0/1984.28.64.1 to 84.28.95.25484.28.95.2558,190
22884.28.96.0/1984.28.96.1 to 84.28.127.25484.28.127.2558,190
22984.28.128.0/1984.28.128.1 to 84.28.159.25484.28.159.2558,190
23084.28.160.0/1984.28.160.1 to 84.28.191.25484.28.191.2558,190
23184.28.192.0/1984.28.192.1 to 84.28.223.25484.28.223.2558,190
23284.28.224.0/1984.28.224.1 to 84.28.255.25484.28.255.2558,190
23384.29.0.0/1984.29.0.1 to 84.29.31.25484.29.31.2558,190
23484.29.32.0/1984.29.32.1 to 84.29.63.25484.29.63.2558,190
23584.29.64.0/1984.29.64.1 to 84.29.95.25484.29.95.2558,190
23684.29.96.0/1984.29.96.1 to 84.29.127.25484.29.127.2558,190
23784.29.128.0/1984.29.128.1 to 84.29.159.25484.29.159.2558,190
23884.29.160.0/1984.29.160.1 to 84.29.191.25484.29.191.2558,190
23984.29.192.0/1984.29.192.1 to 84.29.223.25484.29.223.2558,190
24084.29.224.0/1984.29.224.1 to 84.29.255.25484.29.255.2558,190
24184.30.0.0/1984.30.0.1 to 84.30.31.25484.30.31.2558,190
24284.30.32.0/1984.30.32.1 to 84.30.63.25484.30.63.2558,190
24384.30.64.0/1984.30.64.1 to 84.30.95.25484.30.95.2558,190
24484.30.96.0/1984.30.96.1 to 84.30.127.25484.30.127.2558,190
24584.30.128.0/1984.30.128.1 to 84.30.159.25484.30.159.2558,190
24684.30.160.0/1984.30.160.1 to 84.30.191.25484.30.191.2558,190
24784.30.192.0/1984.30.192.1 to 84.30.223.25484.30.223.2558,190
24884.30.224.0/1984.30.224.1 to 84.30.255.25484.30.255.2558,190
24984.31.0.0/1984.31.0.1 to 84.31.31.25484.31.31.2558,190
25084.31.32.0/1984.31.32.1 to 84.31.63.25484.31.63.2558,190
25184.31.64.0/1984.31.64.1 to 84.31.95.25484.31.95.2558,190
25284.31.96.0/1984.31.96.1 to 84.31.127.25484.31.127.2558,190
25384.31.128.0/1984.31.128.1 to 84.31.159.25484.31.159.2558,190
25484.31.160.0/1984.31.160.1 to 84.31.191.25484.31.191.2558,190
25584.31.192.0/1984.31.192.1 to 84.31.223.25484.31.223.2558,190
25684.31.224.0/1984.31.224.1 to 84.31.255.25484.31.255.2558,190

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.