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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.

Network11.192.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
11.192.0.0
Broadcast address
11.255.255.255
First usable
11.192.0.1
Last usable
11.255.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
A (default /8)
As numbers
Hex 0BC00000 · Integer 197132288 to 201326591
Reverse DNS zones
192.11.in-addr.arpa
193.11.in-addr.arpa
194.11.in-addr.arpa
195.11.in-addr.arpa
196.11.in-addr.arpa
197.11.in-addr.arpa
198.11.in-addr.arpa
199.11.in-addr.arpa
200.11.in-addr.arpa
201.11.in-addr.arpa
202.11.in-addr.arpa
203.11.in-addr.arpa
204.11.in-addr.arpa
205.11.in-addr.arpa
206.11.in-addr.arpa
207.11.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001011.11000000.00000000.0000000011.192.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00001011.11000000.00000000.0000000011.192.0.0
Broadcast00001011.11111111.11111111.1111111111.255.255.255
Split into smaller subnets/18
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

11.192.0.0/10 makes 256 subnets of /18.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
111.192.0.0/1811.192.0.1 to 11.192.63.25411.192.63.25516,382
211.192.64.0/1811.192.64.1 to 11.192.127.25411.192.127.25516,382
311.192.128.0/1811.192.128.1 to 11.192.191.25411.192.191.25516,382
411.192.192.0/1811.192.192.1 to 11.192.255.25411.192.255.25516,382
511.193.0.0/1811.193.0.1 to 11.193.63.25411.193.63.25516,382
611.193.64.0/1811.193.64.1 to 11.193.127.25411.193.127.25516,382
711.193.128.0/1811.193.128.1 to 11.193.191.25411.193.191.25516,382
811.193.192.0/1811.193.192.1 to 11.193.255.25411.193.255.25516,382
911.194.0.0/1811.194.0.1 to 11.194.63.25411.194.63.25516,382
1011.194.64.0/1811.194.64.1 to 11.194.127.25411.194.127.25516,382
1111.194.128.0/1811.194.128.1 to 11.194.191.25411.194.191.25516,382
1211.194.192.0/1811.194.192.1 to 11.194.255.25411.194.255.25516,382
1311.195.0.0/1811.195.0.1 to 11.195.63.25411.195.63.25516,382
1411.195.64.0/1811.195.64.1 to 11.195.127.25411.195.127.25516,382
1511.195.128.0/1811.195.128.1 to 11.195.191.25411.195.191.25516,382
1611.195.192.0/1811.195.192.1 to 11.195.255.25411.195.255.25516,382
1711.196.0.0/1811.196.0.1 to 11.196.63.25411.196.63.25516,382
1811.196.64.0/1811.196.64.1 to 11.196.127.25411.196.127.25516,382
1911.196.128.0/1811.196.128.1 to 11.196.191.25411.196.191.25516,382
2011.196.192.0/1811.196.192.1 to 11.196.255.25411.196.255.25516,382
2111.197.0.0/1811.197.0.1 to 11.197.63.25411.197.63.25516,382
2211.197.64.0/1811.197.64.1 to 11.197.127.25411.197.127.25516,382
2311.197.128.0/1811.197.128.1 to 11.197.191.25411.197.191.25516,382
2411.197.192.0/1811.197.192.1 to 11.197.255.25411.197.255.25516,382
2511.198.0.0/1811.198.0.1 to 11.198.63.25411.198.63.25516,382
2611.198.64.0/1811.198.64.1 to 11.198.127.25411.198.127.25516,382
2711.198.128.0/1811.198.128.1 to 11.198.191.25411.198.191.25516,382
2811.198.192.0/1811.198.192.1 to 11.198.255.25411.198.255.25516,382
2911.199.0.0/1811.199.0.1 to 11.199.63.25411.199.63.25516,382
3011.199.64.0/1811.199.64.1 to 11.199.127.25411.199.127.25516,382
3111.199.128.0/1811.199.128.1 to 11.199.191.25411.199.191.25516,382
3211.199.192.0/1811.199.192.1 to 11.199.255.25411.199.255.25516,382
3311.200.0.0/1811.200.0.1 to 11.200.63.25411.200.63.25516,382
3411.200.64.0/1811.200.64.1 to 11.200.127.25411.200.127.25516,382
3511.200.128.0/1811.200.128.1 to 11.200.191.25411.200.191.25516,382
3611.200.192.0/1811.200.192.1 to 11.200.255.25411.200.255.25516,382
3711.201.0.0/1811.201.0.1 to 11.201.63.25411.201.63.25516,382
3811.201.64.0/1811.201.64.1 to 11.201.127.25411.201.127.25516,382
3911.201.128.0/1811.201.128.1 to 11.201.191.25411.201.191.25516,382
4011.201.192.0/1811.201.192.1 to 11.201.255.25411.201.255.25516,382
4111.202.0.0/1811.202.0.1 to 11.202.63.25411.202.63.25516,382
4211.202.64.0/1811.202.64.1 to 11.202.127.25411.202.127.25516,382
4311.202.128.0/1811.202.128.1 to 11.202.191.25411.202.191.25516,382
4411.202.192.0/1811.202.192.1 to 11.202.255.25411.202.255.25516,382
4511.203.0.0/1811.203.0.1 to 11.203.63.25411.203.63.25516,382
4611.203.64.0/1811.203.64.1 to 11.203.127.25411.203.127.25516,382
4711.203.128.0/1811.203.128.1 to 11.203.191.25411.203.191.25516,382
4811.203.192.0/1811.203.192.1 to 11.203.255.25411.203.255.25516,382
4911.204.0.0/1811.204.0.1 to 11.204.63.25411.204.63.25516,382
5011.204.64.0/1811.204.64.1 to 11.204.127.25411.204.127.25516,382
5111.204.128.0/1811.204.128.1 to 11.204.191.25411.204.191.25516,382
5211.204.192.0/1811.204.192.1 to 11.204.255.25411.204.255.25516,382
5311.205.0.0/1811.205.0.1 to 11.205.63.25411.205.63.25516,382
5411.205.64.0/1811.205.64.1 to 11.205.127.25411.205.127.25516,382
5511.205.128.0/1811.205.128.1 to 11.205.191.25411.205.191.25516,382
5611.205.192.0/1811.205.192.1 to 11.205.255.25411.205.255.25516,382
5711.206.0.0/1811.206.0.1 to 11.206.63.25411.206.63.25516,382
5811.206.64.0/1811.206.64.1 to 11.206.127.25411.206.127.25516,382
5911.206.128.0/1811.206.128.1 to 11.206.191.25411.206.191.25516,382
6011.206.192.0/1811.206.192.1 to 11.206.255.25411.206.255.25516,382
6111.207.0.0/1811.207.0.1 to 11.207.63.25411.207.63.25516,382
6211.207.64.0/1811.207.64.1 to 11.207.127.25411.207.127.25516,382
6311.207.128.0/1811.207.128.1 to 11.207.191.25411.207.191.25516,382
6411.207.192.0/1811.207.192.1 to 11.207.255.25411.207.255.25516,382
6511.208.0.0/1811.208.0.1 to 11.208.63.25411.208.63.25516,382
6611.208.64.0/1811.208.64.1 to 11.208.127.25411.208.127.25516,382
6711.208.128.0/1811.208.128.1 to 11.208.191.25411.208.191.25516,382
6811.208.192.0/1811.208.192.1 to 11.208.255.25411.208.255.25516,382
6911.209.0.0/1811.209.0.1 to 11.209.63.25411.209.63.25516,382
7011.209.64.0/1811.209.64.1 to 11.209.127.25411.209.127.25516,382
7111.209.128.0/1811.209.128.1 to 11.209.191.25411.209.191.25516,382
7211.209.192.0/1811.209.192.1 to 11.209.255.25411.209.255.25516,382
7311.210.0.0/1811.210.0.1 to 11.210.63.25411.210.63.25516,382
7411.210.64.0/1811.210.64.1 to 11.210.127.25411.210.127.25516,382
7511.210.128.0/1811.210.128.1 to 11.210.191.25411.210.191.25516,382
7611.210.192.0/1811.210.192.1 to 11.210.255.25411.210.255.25516,382
7711.211.0.0/1811.211.0.1 to 11.211.63.25411.211.63.25516,382
7811.211.64.0/1811.211.64.1 to 11.211.127.25411.211.127.25516,382
7911.211.128.0/1811.211.128.1 to 11.211.191.25411.211.191.25516,382
8011.211.192.0/1811.211.192.1 to 11.211.255.25411.211.255.25516,382
8111.212.0.0/1811.212.0.1 to 11.212.63.25411.212.63.25516,382
8211.212.64.0/1811.212.64.1 to 11.212.127.25411.212.127.25516,382
8311.212.128.0/1811.212.128.1 to 11.212.191.25411.212.191.25516,382
8411.212.192.0/1811.212.192.1 to 11.212.255.25411.212.255.25516,382
8511.213.0.0/1811.213.0.1 to 11.213.63.25411.213.63.25516,382
8611.213.64.0/1811.213.64.1 to 11.213.127.25411.213.127.25516,382
8711.213.128.0/1811.213.128.1 to 11.213.191.25411.213.191.25516,382
8811.213.192.0/1811.213.192.1 to 11.213.255.25411.213.255.25516,382
8911.214.0.0/1811.214.0.1 to 11.214.63.25411.214.63.25516,382
9011.214.64.0/1811.214.64.1 to 11.214.127.25411.214.127.25516,382
9111.214.128.0/1811.214.128.1 to 11.214.191.25411.214.191.25516,382
9211.214.192.0/1811.214.192.1 to 11.214.255.25411.214.255.25516,382
9311.215.0.0/1811.215.0.1 to 11.215.63.25411.215.63.25516,382
9411.215.64.0/1811.215.64.1 to 11.215.127.25411.215.127.25516,382
9511.215.128.0/1811.215.128.1 to 11.215.191.25411.215.191.25516,382
9611.215.192.0/1811.215.192.1 to 11.215.255.25411.215.255.25516,382
9711.216.0.0/1811.216.0.1 to 11.216.63.25411.216.63.25516,382
9811.216.64.0/1811.216.64.1 to 11.216.127.25411.216.127.25516,382
9911.216.128.0/1811.216.128.1 to 11.216.191.25411.216.191.25516,382
10011.216.192.0/1811.216.192.1 to 11.216.255.25411.216.255.25516,382
10111.217.0.0/1811.217.0.1 to 11.217.63.25411.217.63.25516,382
10211.217.64.0/1811.217.64.1 to 11.217.127.25411.217.127.25516,382
10311.217.128.0/1811.217.128.1 to 11.217.191.25411.217.191.25516,382
10411.217.192.0/1811.217.192.1 to 11.217.255.25411.217.255.25516,382
10511.218.0.0/1811.218.0.1 to 11.218.63.25411.218.63.25516,382
10611.218.64.0/1811.218.64.1 to 11.218.127.25411.218.127.25516,382
10711.218.128.0/1811.218.128.1 to 11.218.191.25411.218.191.25516,382
10811.218.192.0/1811.218.192.1 to 11.218.255.25411.218.255.25516,382
10911.219.0.0/1811.219.0.1 to 11.219.63.25411.219.63.25516,382
11011.219.64.0/1811.219.64.1 to 11.219.127.25411.219.127.25516,382
11111.219.128.0/1811.219.128.1 to 11.219.191.25411.219.191.25516,382
11211.219.192.0/1811.219.192.1 to 11.219.255.25411.219.255.25516,382
11311.220.0.0/1811.220.0.1 to 11.220.63.25411.220.63.25516,382
11411.220.64.0/1811.220.64.1 to 11.220.127.25411.220.127.25516,382
11511.220.128.0/1811.220.128.1 to 11.220.191.25411.220.191.25516,382
11611.220.192.0/1811.220.192.1 to 11.220.255.25411.220.255.25516,382
11711.221.0.0/1811.221.0.1 to 11.221.63.25411.221.63.25516,382
11811.221.64.0/1811.221.64.1 to 11.221.127.25411.221.127.25516,382
11911.221.128.0/1811.221.128.1 to 11.221.191.25411.221.191.25516,382
12011.221.192.0/1811.221.192.1 to 11.221.255.25411.221.255.25516,382
12111.222.0.0/1811.222.0.1 to 11.222.63.25411.222.63.25516,382
12211.222.64.0/1811.222.64.1 to 11.222.127.25411.222.127.25516,382
12311.222.128.0/1811.222.128.1 to 11.222.191.25411.222.191.25516,382
12411.222.192.0/1811.222.192.1 to 11.222.255.25411.222.255.25516,382
12511.223.0.0/1811.223.0.1 to 11.223.63.25411.223.63.25516,382
12611.223.64.0/1811.223.64.1 to 11.223.127.25411.223.127.25516,382
12711.223.128.0/1811.223.128.1 to 11.223.191.25411.223.191.25516,382
12811.223.192.0/1811.223.192.1 to 11.223.255.25411.223.255.25516,382
12911.224.0.0/1811.224.0.1 to 11.224.63.25411.224.63.25516,382
13011.224.64.0/1811.224.64.1 to 11.224.127.25411.224.127.25516,382
13111.224.128.0/1811.224.128.1 to 11.224.191.25411.224.191.25516,382
13211.224.192.0/1811.224.192.1 to 11.224.255.25411.224.255.25516,382
13311.225.0.0/1811.225.0.1 to 11.225.63.25411.225.63.25516,382
13411.225.64.0/1811.225.64.1 to 11.225.127.25411.225.127.25516,382
13511.225.128.0/1811.225.128.1 to 11.225.191.25411.225.191.25516,382
13611.225.192.0/1811.225.192.1 to 11.225.255.25411.225.255.25516,382
13711.226.0.0/1811.226.0.1 to 11.226.63.25411.226.63.25516,382
13811.226.64.0/1811.226.64.1 to 11.226.127.25411.226.127.25516,382
13911.226.128.0/1811.226.128.1 to 11.226.191.25411.226.191.25516,382
14011.226.192.0/1811.226.192.1 to 11.226.255.25411.226.255.25516,382
14111.227.0.0/1811.227.0.1 to 11.227.63.25411.227.63.25516,382
14211.227.64.0/1811.227.64.1 to 11.227.127.25411.227.127.25516,382
14311.227.128.0/1811.227.128.1 to 11.227.191.25411.227.191.25516,382
14411.227.192.0/1811.227.192.1 to 11.227.255.25411.227.255.25516,382
14511.228.0.0/1811.228.0.1 to 11.228.63.25411.228.63.25516,382
14611.228.64.0/1811.228.64.1 to 11.228.127.25411.228.127.25516,382
14711.228.128.0/1811.228.128.1 to 11.228.191.25411.228.191.25516,382
14811.228.192.0/1811.228.192.1 to 11.228.255.25411.228.255.25516,382
14911.229.0.0/1811.229.0.1 to 11.229.63.25411.229.63.25516,382
15011.229.64.0/1811.229.64.1 to 11.229.127.25411.229.127.25516,382
15111.229.128.0/1811.229.128.1 to 11.229.191.25411.229.191.25516,382
15211.229.192.0/1811.229.192.1 to 11.229.255.25411.229.255.25516,382
15311.230.0.0/1811.230.0.1 to 11.230.63.25411.230.63.25516,382
15411.230.64.0/1811.230.64.1 to 11.230.127.25411.230.127.25516,382
15511.230.128.0/1811.230.128.1 to 11.230.191.25411.230.191.25516,382
15611.230.192.0/1811.230.192.1 to 11.230.255.25411.230.255.25516,382
15711.231.0.0/1811.231.0.1 to 11.231.63.25411.231.63.25516,382
15811.231.64.0/1811.231.64.1 to 11.231.127.25411.231.127.25516,382
15911.231.128.0/1811.231.128.1 to 11.231.191.25411.231.191.25516,382
16011.231.192.0/1811.231.192.1 to 11.231.255.25411.231.255.25516,382
16111.232.0.0/1811.232.0.1 to 11.232.63.25411.232.63.25516,382
16211.232.64.0/1811.232.64.1 to 11.232.127.25411.232.127.25516,382
16311.232.128.0/1811.232.128.1 to 11.232.191.25411.232.191.25516,382
16411.232.192.0/1811.232.192.1 to 11.232.255.25411.232.255.25516,382
16511.233.0.0/1811.233.0.1 to 11.233.63.25411.233.63.25516,382
16611.233.64.0/1811.233.64.1 to 11.233.127.25411.233.127.25516,382
16711.233.128.0/1811.233.128.1 to 11.233.191.25411.233.191.25516,382
16811.233.192.0/1811.233.192.1 to 11.233.255.25411.233.255.25516,382
16911.234.0.0/1811.234.0.1 to 11.234.63.25411.234.63.25516,382
17011.234.64.0/1811.234.64.1 to 11.234.127.25411.234.127.25516,382
17111.234.128.0/1811.234.128.1 to 11.234.191.25411.234.191.25516,382
17211.234.192.0/1811.234.192.1 to 11.234.255.25411.234.255.25516,382
17311.235.0.0/1811.235.0.1 to 11.235.63.25411.235.63.25516,382
17411.235.64.0/1811.235.64.1 to 11.235.127.25411.235.127.25516,382
17511.235.128.0/1811.235.128.1 to 11.235.191.25411.235.191.25516,382
17611.235.192.0/1811.235.192.1 to 11.235.255.25411.235.255.25516,382
17711.236.0.0/1811.236.0.1 to 11.236.63.25411.236.63.25516,382
17811.236.64.0/1811.236.64.1 to 11.236.127.25411.236.127.25516,382
17911.236.128.0/1811.236.128.1 to 11.236.191.25411.236.191.25516,382
18011.236.192.0/1811.236.192.1 to 11.236.255.25411.236.255.25516,382
18111.237.0.0/1811.237.0.1 to 11.237.63.25411.237.63.25516,382
18211.237.64.0/1811.237.64.1 to 11.237.127.25411.237.127.25516,382
18311.237.128.0/1811.237.128.1 to 11.237.191.25411.237.191.25516,382
18411.237.192.0/1811.237.192.1 to 11.237.255.25411.237.255.25516,382
18511.238.0.0/1811.238.0.1 to 11.238.63.25411.238.63.25516,382
18611.238.64.0/1811.238.64.1 to 11.238.127.25411.238.127.25516,382
18711.238.128.0/1811.238.128.1 to 11.238.191.25411.238.191.25516,382
18811.238.192.0/1811.238.192.1 to 11.238.255.25411.238.255.25516,382
18911.239.0.0/1811.239.0.1 to 11.239.63.25411.239.63.25516,382
19011.239.64.0/1811.239.64.1 to 11.239.127.25411.239.127.25516,382
19111.239.128.0/1811.239.128.1 to 11.239.191.25411.239.191.25516,382
19211.239.192.0/1811.239.192.1 to 11.239.255.25411.239.255.25516,382
19311.240.0.0/1811.240.0.1 to 11.240.63.25411.240.63.25516,382
19411.240.64.0/1811.240.64.1 to 11.240.127.25411.240.127.25516,382
19511.240.128.0/1811.240.128.1 to 11.240.191.25411.240.191.25516,382
19611.240.192.0/1811.240.192.1 to 11.240.255.25411.240.255.25516,382
19711.241.0.0/1811.241.0.1 to 11.241.63.25411.241.63.25516,382
19811.241.64.0/1811.241.64.1 to 11.241.127.25411.241.127.25516,382
19911.241.128.0/1811.241.128.1 to 11.241.191.25411.241.191.25516,382
20011.241.192.0/1811.241.192.1 to 11.241.255.25411.241.255.25516,382
20111.242.0.0/1811.242.0.1 to 11.242.63.25411.242.63.25516,382
20211.242.64.0/1811.242.64.1 to 11.242.127.25411.242.127.25516,382
20311.242.128.0/1811.242.128.1 to 11.242.191.25411.242.191.25516,382
20411.242.192.0/1811.242.192.1 to 11.242.255.25411.242.255.25516,382
20511.243.0.0/1811.243.0.1 to 11.243.63.25411.243.63.25516,382
20611.243.64.0/1811.243.64.1 to 11.243.127.25411.243.127.25516,382
20711.243.128.0/1811.243.128.1 to 11.243.191.25411.243.191.25516,382
20811.243.192.0/1811.243.192.1 to 11.243.255.25411.243.255.25516,382
20911.244.0.0/1811.244.0.1 to 11.244.63.25411.244.63.25516,382
21011.244.64.0/1811.244.64.1 to 11.244.127.25411.244.127.25516,382
21111.244.128.0/1811.244.128.1 to 11.244.191.25411.244.191.25516,382
21211.244.192.0/1811.244.192.1 to 11.244.255.25411.244.255.25516,382
21311.245.0.0/1811.245.0.1 to 11.245.63.25411.245.63.25516,382
21411.245.64.0/1811.245.64.1 to 11.245.127.25411.245.127.25516,382
21511.245.128.0/1811.245.128.1 to 11.245.191.25411.245.191.25516,382
21611.245.192.0/1811.245.192.1 to 11.245.255.25411.245.255.25516,382
21711.246.0.0/1811.246.0.1 to 11.246.63.25411.246.63.25516,382
21811.246.64.0/1811.246.64.1 to 11.246.127.25411.246.127.25516,382
21911.246.128.0/1811.246.128.1 to 11.246.191.25411.246.191.25516,382
22011.246.192.0/1811.246.192.1 to 11.246.255.25411.246.255.25516,382
22111.247.0.0/1811.247.0.1 to 11.247.63.25411.247.63.25516,382
22211.247.64.0/1811.247.64.1 to 11.247.127.25411.247.127.25516,382
22311.247.128.0/1811.247.128.1 to 11.247.191.25411.247.191.25516,382
22411.247.192.0/1811.247.192.1 to 11.247.255.25411.247.255.25516,382
22511.248.0.0/1811.248.0.1 to 11.248.63.25411.248.63.25516,382
22611.248.64.0/1811.248.64.1 to 11.248.127.25411.248.127.25516,382
22711.248.128.0/1811.248.128.1 to 11.248.191.25411.248.191.25516,382
22811.248.192.0/1811.248.192.1 to 11.248.255.25411.248.255.25516,382
22911.249.0.0/1811.249.0.1 to 11.249.63.25411.249.63.25516,382
23011.249.64.0/1811.249.64.1 to 11.249.127.25411.249.127.25516,382
23111.249.128.0/1811.249.128.1 to 11.249.191.25411.249.191.25516,382
23211.249.192.0/1811.249.192.1 to 11.249.255.25411.249.255.25516,382
23311.250.0.0/1811.250.0.1 to 11.250.63.25411.250.63.25516,382
23411.250.64.0/1811.250.64.1 to 11.250.127.25411.250.127.25516,382
23511.250.128.0/1811.250.128.1 to 11.250.191.25411.250.191.25516,382
23611.250.192.0/1811.250.192.1 to 11.250.255.25411.250.255.25516,382
23711.251.0.0/1811.251.0.1 to 11.251.63.25411.251.63.25516,382
23811.251.64.0/1811.251.64.1 to 11.251.127.25411.251.127.25516,382
23911.251.128.0/1811.251.128.1 to 11.251.191.25411.251.191.25516,382
24011.251.192.0/1811.251.192.1 to 11.251.255.25411.251.255.25516,382
24111.252.0.0/1811.252.0.1 to 11.252.63.25411.252.63.25516,382
24211.252.64.0/1811.252.64.1 to 11.252.127.25411.252.127.25516,382
24311.252.128.0/1811.252.128.1 to 11.252.191.25411.252.191.25516,382
24411.252.192.0/1811.252.192.1 to 11.252.255.25411.252.255.25516,382
24511.253.0.0/1811.253.0.1 to 11.253.63.25411.253.63.25516,382
24611.253.64.0/1811.253.64.1 to 11.253.127.25411.253.127.25516,382
24711.253.128.0/1811.253.128.1 to 11.253.191.25411.253.191.25516,382
24811.253.192.0/1811.253.192.1 to 11.253.255.25411.253.255.25516,382
24911.254.0.0/1811.254.0.1 to 11.254.63.25411.254.63.25516,382
25011.254.64.0/1811.254.64.1 to 11.254.127.25411.254.127.25516,382
25111.254.128.0/1811.254.128.1 to 11.254.191.25411.254.191.25516,382
25211.254.192.0/1811.254.192.1 to 11.254.255.25411.254.255.25516,382
25311.255.0.0/1811.255.0.1 to 11.255.63.25411.255.63.25516,382
25411.255.64.0/1811.255.64.1 to 11.255.127.25411.255.127.25516,382
25511.255.128.0/1811.255.128.1 to 11.255.191.25411.255.191.25516,382
25611.255.192.0/1811.255.192.1 to 11.255.255.25411.255.255.25516,382

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.