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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.

Network49.192.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
49.192.0.0
Broadcast address
49.255.255.255
First usable
49.192.0.1
Last usable
49.255.255.254
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 31C00000 · Integer 834666496 to 838860799
Reverse DNS zones
192.49.in-addr.arpa
193.49.in-addr.arpa
194.49.in-addr.arpa
195.49.in-addr.arpa
196.49.in-addr.arpa
197.49.in-addr.arpa
198.49.in-addr.arpa
199.49.in-addr.arpa
200.49.in-addr.arpa
201.49.in-addr.arpa
202.49.in-addr.arpa
203.49.in-addr.arpa
204.49.in-addr.arpa
205.49.in-addr.arpa
206.49.in-addr.arpa
207.49.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
Address00110001.11000000.00000000.0000000049.192.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00110001.11000000.00000000.0000000049.192.0.0
Broadcast00110001.11111111.11111111.1111111149.255.255.255
Split into smaller subnets/19
/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)

49.192.0.0/10 makes 512 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
149.192.0.0/1949.192.0.1 to 49.192.31.25449.192.31.2558,190
249.192.32.0/1949.192.32.1 to 49.192.63.25449.192.63.2558,190
349.192.64.0/1949.192.64.1 to 49.192.95.25449.192.95.2558,190
449.192.96.0/1949.192.96.1 to 49.192.127.25449.192.127.2558,190
549.192.128.0/1949.192.128.1 to 49.192.159.25449.192.159.2558,190
649.192.160.0/1949.192.160.1 to 49.192.191.25449.192.191.2558,190
749.192.192.0/1949.192.192.1 to 49.192.223.25449.192.223.2558,190
849.192.224.0/1949.192.224.1 to 49.192.255.25449.192.255.2558,190
949.193.0.0/1949.193.0.1 to 49.193.31.25449.193.31.2558,190
1049.193.32.0/1949.193.32.1 to 49.193.63.25449.193.63.2558,190
1149.193.64.0/1949.193.64.1 to 49.193.95.25449.193.95.2558,190
1249.193.96.0/1949.193.96.1 to 49.193.127.25449.193.127.2558,190
1349.193.128.0/1949.193.128.1 to 49.193.159.25449.193.159.2558,190
1449.193.160.0/1949.193.160.1 to 49.193.191.25449.193.191.2558,190
1549.193.192.0/1949.193.192.1 to 49.193.223.25449.193.223.2558,190
1649.193.224.0/1949.193.224.1 to 49.193.255.25449.193.255.2558,190
1749.194.0.0/1949.194.0.1 to 49.194.31.25449.194.31.2558,190
1849.194.32.0/1949.194.32.1 to 49.194.63.25449.194.63.2558,190
1949.194.64.0/1949.194.64.1 to 49.194.95.25449.194.95.2558,190
2049.194.96.0/1949.194.96.1 to 49.194.127.25449.194.127.2558,190
2149.194.128.0/1949.194.128.1 to 49.194.159.25449.194.159.2558,190
2249.194.160.0/1949.194.160.1 to 49.194.191.25449.194.191.2558,190
2349.194.192.0/1949.194.192.1 to 49.194.223.25449.194.223.2558,190
2449.194.224.0/1949.194.224.1 to 49.194.255.25449.194.255.2558,190
2549.195.0.0/1949.195.0.1 to 49.195.31.25449.195.31.2558,190
2649.195.32.0/1949.195.32.1 to 49.195.63.25449.195.63.2558,190
2749.195.64.0/1949.195.64.1 to 49.195.95.25449.195.95.2558,190
2849.195.96.0/1949.195.96.1 to 49.195.127.25449.195.127.2558,190
2949.195.128.0/1949.195.128.1 to 49.195.159.25449.195.159.2558,190
3049.195.160.0/1949.195.160.1 to 49.195.191.25449.195.191.2558,190
3149.195.192.0/1949.195.192.1 to 49.195.223.25449.195.223.2558,190
3249.195.224.0/1949.195.224.1 to 49.195.255.25449.195.255.2558,190
3349.196.0.0/1949.196.0.1 to 49.196.31.25449.196.31.2558,190
3449.196.32.0/1949.196.32.1 to 49.196.63.25449.196.63.2558,190
3549.196.64.0/1949.196.64.1 to 49.196.95.25449.196.95.2558,190
3649.196.96.0/1949.196.96.1 to 49.196.127.25449.196.127.2558,190
3749.196.128.0/1949.196.128.1 to 49.196.159.25449.196.159.2558,190
3849.196.160.0/1949.196.160.1 to 49.196.191.25449.196.191.2558,190
3949.196.192.0/1949.196.192.1 to 49.196.223.25449.196.223.2558,190
4049.196.224.0/1949.196.224.1 to 49.196.255.25449.196.255.2558,190
4149.197.0.0/1949.197.0.1 to 49.197.31.25449.197.31.2558,190
4249.197.32.0/1949.197.32.1 to 49.197.63.25449.197.63.2558,190
4349.197.64.0/1949.197.64.1 to 49.197.95.25449.197.95.2558,190
4449.197.96.0/1949.197.96.1 to 49.197.127.25449.197.127.2558,190
4549.197.128.0/1949.197.128.1 to 49.197.159.25449.197.159.2558,190
4649.197.160.0/1949.197.160.1 to 49.197.191.25449.197.191.2558,190
4749.197.192.0/1949.197.192.1 to 49.197.223.25449.197.223.2558,190
4849.197.224.0/1949.197.224.1 to 49.197.255.25449.197.255.2558,190
4949.198.0.0/1949.198.0.1 to 49.198.31.25449.198.31.2558,190
5049.198.32.0/1949.198.32.1 to 49.198.63.25449.198.63.2558,190
5149.198.64.0/1949.198.64.1 to 49.198.95.25449.198.95.2558,190
5249.198.96.0/1949.198.96.1 to 49.198.127.25449.198.127.2558,190
5349.198.128.0/1949.198.128.1 to 49.198.159.25449.198.159.2558,190
5449.198.160.0/1949.198.160.1 to 49.198.191.25449.198.191.2558,190
5549.198.192.0/1949.198.192.1 to 49.198.223.25449.198.223.2558,190
5649.198.224.0/1949.198.224.1 to 49.198.255.25449.198.255.2558,190
5749.199.0.0/1949.199.0.1 to 49.199.31.25449.199.31.2558,190
5849.199.32.0/1949.199.32.1 to 49.199.63.25449.199.63.2558,190
5949.199.64.0/1949.199.64.1 to 49.199.95.25449.199.95.2558,190
6049.199.96.0/1949.199.96.1 to 49.199.127.25449.199.127.2558,190
6149.199.128.0/1949.199.128.1 to 49.199.159.25449.199.159.2558,190
6249.199.160.0/1949.199.160.1 to 49.199.191.25449.199.191.2558,190
6349.199.192.0/1949.199.192.1 to 49.199.223.25449.199.223.2558,190
6449.199.224.0/1949.199.224.1 to 49.199.255.25449.199.255.2558,190
6549.200.0.0/1949.200.0.1 to 49.200.31.25449.200.31.2558,190
6649.200.32.0/1949.200.32.1 to 49.200.63.25449.200.63.2558,190
6749.200.64.0/1949.200.64.1 to 49.200.95.25449.200.95.2558,190
6849.200.96.0/1949.200.96.1 to 49.200.127.25449.200.127.2558,190
6949.200.128.0/1949.200.128.1 to 49.200.159.25449.200.159.2558,190
7049.200.160.0/1949.200.160.1 to 49.200.191.25449.200.191.2558,190
7149.200.192.0/1949.200.192.1 to 49.200.223.25449.200.223.2558,190
7249.200.224.0/1949.200.224.1 to 49.200.255.25449.200.255.2558,190
7349.201.0.0/1949.201.0.1 to 49.201.31.25449.201.31.2558,190
7449.201.32.0/1949.201.32.1 to 49.201.63.25449.201.63.2558,190
7549.201.64.0/1949.201.64.1 to 49.201.95.25449.201.95.2558,190
7649.201.96.0/1949.201.96.1 to 49.201.127.25449.201.127.2558,190
7749.201.128.0/1949.201.128.1 to 49.201.159.25449.201.159.2558,190
7849.201.160.0/1949.201.160.1 to 49.201.191.25449.201.191.2558,190
7949.201.192.0/1949.201.192.1 to 49.201.223.25449.201.223.2558,190
8049.201.224.0/1949.201.224.1 to 49.201.255.25449.201.255.2558,190
8149.202.0.0/1949.202.0.1 to 49.202.31.25449.202.31.2558,190
8249.202.32.0/1949.202.32.1 to 49.202.63.25449.202.63.2558,190
8349.202.64.0/1949.202.64.1 to 49.202.95.25449.202.95.2558,190
8449.202.96.0/1949.202.96.1 to 49.202.127.25449.202.127.2558,190
8549.202.128.0/1949.202.128.1 to 49.202.159.25449.202.159.2558,190
8649.202.160.0/1949.202.160.1 to 49.202.191.25449.202.191.2558,190
8749.202.192.0/1949.202.192.1 to 49.202.223.25449.202.223.2558,190
8849.202.224.0/1949.202.224.1 to 49.202.255.25449.202.255.2558,190
8949.203.0.0/1949.203.0.1 to 49.203.31.25449.203.31.2558,190
9049.203.32.0/1949.203.32.1 to 49.203.63.25449.203.63.2558,190
9149.203.64.0/1949.203.64.1 to 49.203.95.25449.203.95.2558,190
9249.203.96.0/1949.203.96.1 to 49.203.127.25449.203.127.2558,190
9349.203.128.0/1949.203.128.1 to 49.203.159.25449.203.159.2558,190
9449.203.160.0/1949.203.160.1 to 49.203.191.25449.203.191.2558,190
9549.203.192.0/1949.203.192.1 to 49.203.223.25449.203.223.2558,190
9649.203.224.0/1949.203.224.1 to 49.203.255.25449.203.255.2558,190
9749.204.0.0/1949.204.0.1 to 49.204.31.25449.204.31.2558,190
9849.204.32.0/1949.204.32.1 to 49.204.63.25449.204.63.2558,190
9949.204.64.0/1949.204.64.1 to 49.204.95.25449.204.95.2558,190
10049.204.96.0/1949.204.96.1 to 49.204.127.25449.204.127.2558,190
10149.204.128.0/1949.204.128.1 to 49.204.159.25449.204.159.2558,190
10249.204.160.0/1949.204.160.1 to 49.204.191.25449.204.191.2558,190
10349.204.192.0/1949.204.192.1 to 49.204.223.25449.204.223.2558,190
10449.204.224.0/1949.204.224.1 to 49.204.255.25449.204.255.2558,190
10549.205.0.0/1949.205.0.1 to 49.205.31.25449.205.31.2558,190
10649.205.32.0/1949.205.32.1 to 49.205.63.25449.205.63.2558,190
10749.205.64.0/1949.205.64.1 to 49.205.95.25449.205.95.2558,190
10849.205.96.0/1949.205.96.1 to 49.205.127.25449.205.127.2558,190
10949.205.128.0/1949.205.128.1 to 49.205.159.25449.205.159.2558,190
11049.205.160.0/1949.205.160.1 to 49.205.191.25449.205.191.2558,190
11149.205.192.0/1949.205.192.1 to 49.205.223.25449.205.223.2558,190
11249.205.224.0/1949.205.224.1 to 49.205.255.25449.205.255.2558,190
11349.206.0.0/1949.206.0.1 to 49.206.31.25449.206.31.2558,190
11449.206.32.0/1949.206.32.1 to 49.206.63.25449.206.63.2558,190
11549.206.64.0/1949.206.64.1 to 49.206.95.25449.206.95.2558,190
11649.206.96.0/1949.206.96.1 to 49.206.127.25449.206.127.2558,190
11749.206.128.0/1949.206.128.1 to 49.206.159.25449.206.159.2558,190
11849.206.160.0/1949.206.160.1 to 49.206.191.25449.206.191.2558,190
11949.206.192.0/1949.206.192.1 to 49.206.223.25449.206.223.2558,190
12049.206.224.0/1949.206.224.1 to 49.206.255.25449.206.255.2558,190
12149.207.0.0/1949.207.0.1 to 49.207.31.25449.207.31.2558,190
12249.207.32.0/1949.207.32.1 to 49.207.63.25449.207.63.2558,190
12349.207.64.0/1949.207.64.1 to 49.207.95.25449.207.95.2558,190
12449.207.96.0/1949.207.96.1 to 49.207.127.25449.207.127.2558,190
12549.207.128.0/1949.207.128.1 to 49.207.159.25449.207.159.2558,190
12649.207.160.0/1949.207.160.1 to 49.207.191.25449.207.191.2558,190
12749.207.192.0/1949.207.192.1 to 49.207.223.25449.207.223.2558,190
12849.207.224.0/1949.207.224.1 to 49.207.255.25449.207.255.2558,190
12949.208.0.0/1949.208.0.1 to 49.208.31.25449.208.31.2558,190
13049.208.32.0/1949.208.32.1 to 49.208.63.25449.208.63.2558,190
13149.208.64.0/1949.208.64.1 to 49.208.95.25449.208.95.2558,190
13249.208.96.0/1949.208.96.1 to 49.208.127.25449.208.127.2558,190
13349.208.128.0/1949.208.128.1 to 49.208.159.25449.208.159.2558,190
13449.208.160.0/1949.208.160.1 to 49.208.191.25449.208.191.2558,190
13549.208.192.0/1949.208.192.1 to 49.208.223.25449.208.223.2558,190
13649.208.224.0/1949.208.224.1 to 49.208.255.25449.208.255.2558,190
13749.209.0.0/1949.209.0.1 to 49.209.31.25449.209.31.2558,190
13849.209.32.0/1949.209.32.1 to 49.209.63.25449.209.63.2558,190
13949.209.64.0/1949.209.64.1 to 49.209.95.25449.209.95.2558,190
14049.209.96.0/1949.209.96.1 to 49.209.127.25449.209.127.2558,190
14149.209.128.0/1949.209.128.1 to 49.209.159.25449.209.159.2558,190
14249.209.160.0/1949.209.160.1 to 49.209.191.25449.209.191.2558,190
14349.209.192.0/1949.209.192.1 to 49.209.223.25449.209.223.2558,190
14449.209.224.0/1949.209.224.1 to 49.209.255.25449.209.255.2558,190
14549.210.0.0/1949.210.0.1 to 49.210.31.25449.210.31.2558,190
14649.210.32.0/1949.210.32.1 to 49.210.63.25449.210.63.2558,190
14749.210.64.0/1949.210.64.1 to 49.210.95.25449.210.95.2558,190
14849.210.96.0/1949.210.96.1 to 49.210.127.25449.210.127.2558,190
14949.210.128.0/1949.210.128.1 to 49.210.159.25449.210.159.2558,190
15049.210.160.0/1949.210.160.1 to 49.210.191.25449.210.191.2558,190
15149.210.192.0/1949.210.192.1 to 49.210.223.25449.210.223.2558,190
15249.210.224.0/1949.210.224.1 to 49.210.255.25449.210.255.2558,190
15349.211.0.0/1949.211.0.1 to 49.211.31.25449.211.31.2558,190
15449.211.32.0/1949.211.32.1 to 49.211.63.25449.211.63.2558,190
15549.211.64.0/1949.211.64.1 to 49.211.95.25449.211.95.2558,190
15649.211.96.0/1949.211.96.1 to 49.211.127.25449.211.127.2558,190
15749.211.128.0/1949.211.128.1 to 49.211.159.25449.211.159.2558,190
15849.211.160.0/1949.211.160.1 to 49.211.191.25449.211.191.2558,190
15949.211.192.0/1949.211.192.1 to 49.211.223.25449.211.223.2558,190
16049.211.224.0/1949.211.224.1 to 49.211.255.25449.211.255.2558,190
16149.212.0.0/1949.212.0.1 to 49.212.31.25449.212.31.2558,190
16249.212.32.0/1949.212.32.1 to 49.212.63.25449.212.63.2558,190
16349.212.64.0/1949.212.64.1 to 49.212.95.25449.212.95.2558,190
16449.212.96.0/1949.212.96.1 to 49.212.127.25449.212.127.2558,190
16549.212.128.0/1949.212.128.1 to 49.212.159.25449.212.159.2558,190
16649.212.160.0/1949.212.160.1 to 49.212.191.25449.212.191.2558,190
16749.212.192.0/1949.212.192.1 to 49.212.223.25449.212.223.2558,190
16849.212.224.0/1949.212.224.1 to 49.212.255.25449.212.255.2558,190
16949.213.0.0/1949.213.0.1 to 49.213.31.25449.213.31.2558,190
17049.213.32.0/1949.213.32.1 to 49.213.63.25449.213.63.2558,190
17149.213.64.0/1949.213.64.1 to 49.213.95.25449.213.95.2558,190
17249.213.96.0/1949.213.96.1 to 49.213.127.25449.213.127.2558,190
17349.213.128.0/1949.213.128.1 to 49.213.159.25449.213.159.2558,190
17449.213.160.0/1949.213.160.1 to 49.213.191.25449.213.191.2558,190
17549.213.192.0/1949.213.192.1 to 49.213.223.25449.213.223.2558,190
17649.213.224.0/1949.213.224.1 to 49.213.255.25449.213.255.2558,190
17749.214.0.0/1949.214.0.1 to 49.214.31.25449.214.31.2558,190
17849.214.32.0/1949.214.32.1 to 49.214.63.25449.214.63.2558,190
17949.214.64.0/1949.214.64.1 to 49.214.95.25449.214.95.2558,190
18049.214.96.0/1949.214.96.1 to 49.214.127.25449.214.127.2558,190
18149.214.128.0/1949.214.128.1 to 49.214.159.25449.214.159.2558,190
18249.214.160.0/1949.214.160.1 to 49.214.191.25449.214.191.2558,190
18349.214.192.0/1949.214.192.1 to 49.214.223.25449.214.223.2558,190
18449.214.224.0/1949.214.224.1 to 49.214.255.25449.214.255.2558,190
18549.215.0.0/1949.215.0.1 to 49.215.31.25449.215.31.2558,190
18649.215.32.0/1949.215.32.1 to 49.215.63.25449.215.63.2558,190
18749.215.64.0/1949.215.64.1 to 49.215.95.25449.215.95.2558,190
18849.215.96.0/1949.215.96.1 to 49.215.127.25449.215.127.2558,190
18949.215.128.0/1949.215.128.1 to 49.215.159.25449.215.159.2558,190
19049.215.160.0/1949.215.160.1 to 49.215.191.25449.215.191.2558,190
19149.215.192.0/1949.215.192.1 to 49.215.223.25449.215.223.2558,190
19249.215.224.0/1949.215.224.1 to 49.215.255.25449.215.255.2558,190
19349.216.0.0/1949.216.0.1 to 49.216.31.25449.216.31.2558,190
19449.216.32.0/1949.216.32.1 to 49.216.63.25449.216.63.2558,190
19549.216.64.0/1949.216.64.1 to 49.216.95.25449.216.95.2558,190
19649.216.96.0/1949.216.96.1 to 49.216.127.25449.216.127.2558,190
19749.216.128.0/1949.216.128.1 to 49.216.159.25449.216.159.2558,190
19849.216.160.0/1949.216.160.1 to 49.216.191.25449.216.191.2558,190
19949.216.192.0/1949.216.192.1 to 49.216.223.25449.216.223.2558,190
20049.216.224.0/1949.216.224.1 to 49.216.255.25449.216.255.2558,190
20149.217.0.0/1949.217.0.1 to 49.217.31.25449.217.31.2558,190
20249.217.32.0/1949.217.32.1 to 49.217.63.25449.217.63.2558,190
20349.217.64.0/1949.217.64.1 to 49.217.95.25449.217.95.2558,190
20449.217.96.0/1949.217.96.1 to 49.217.127.25449.217.127.2558,190
20549.217.128.0/1949.217.128.1 to 49.217.159.25449.217.159.2558,190
20649.217.160.0/1949.217.160.1 to 49.217.191.25449.217.191.2558,190
20749.217.192.0/1949.217.192.1 to 49.217.223.25449.217.223.2558,190
20849.217.224.0/1949.217.224.1 to 49.217.255.25449.217.255.2558,190
20949.218.0.0/1949.218.0.1 to 49.218.31.25449.218.31.2558,190
21049.218.32.0/1949.218.32.1 to 49.218.63.25449.218.63.2558,190
21149.218.64.0/1949.218.64.1 to 49.218.95.25449.218.95.2558,190
21249.218.96.0/1949.218.96.1 to 49.218.127.25449.218.127.2558,190
21349.218.128.0/1949.218.128.1 to 49.218.159.25449.218.159.2558,190
21449.218.160.0/1949.218.160.1 to 49.218.191.25449.218.191.2558,190
21549.218.192.0/1949.218.192.1 to 49.218.223.25449.218.223.2558,190
21649.218.224.0/1949.218.224.1 to 49.218.255.25449.218.255.2558,190
21749.219.0.0/1949.219.0.1 to 49.219.31.25449.219.31.2558,190
21849.219.32.0/1949.219.32.1 to 49.219.63.25449.219.63.2558,190
21949.219.64.0/1949.219.64.1 to 49.219.95.25449.219.95.2558,190
22049.219.96.0/1949.219.96.1 to 49.219.127.25449.219.127.2558,190
22149.219.128.0/1949.219.128.1 to 49.219.159.25449.219.159.2558,190
22249.219.160.0/1949.219.160.1 to 49.219.191.25449.219.191.2558,190
22349.219.192.0/1949.219.192.1 to 49.219.223.25449.219.223.2558,190
22449.219.224.0/1949.219.224.1 to 49.219.255.25449.219.255.2558,190
22549.220.0.0/1949.220.0.1 to 49.220.31.25449.220.31.2558,190
22649.220.32.0/1949.220.32.1 to 49.220.63.25449.220.63.2558,190
22749.220.64.0/1949.220.64.1 to 49.220.95.25449.220.95.2558,190
22849.220.96.0/1949.220.96.1 to 49.220.127.25449.220.127.2558,190
22949.220.128.0/1949.220.128.1 to 49.220.159.25449.220.159.2558,190
23049.220.160.0/1949.220.160.1 to 49.220.191.25449.220.191.2558,190
23149.220.192.0/1949.220.192.1 to 49.220.223.25449.220.223.2558,190
23249.220.224.0/1949.220.224.1 to 49.220.255.25449.220.255.2558,190
23349.221.0.0/1949.221.0.1 to 49.221.31.25449.221.31.2558,190
23449.221.32.0/1949.221.32.1 to 49.221.63.25449.221.63.2558,190
23549.221.64.0/1949.221.64.1 to 49.221.95.25449.221.95.2558,190
23649.221.96.0/1949.221.96.1 to 49.221.127.25449.221.127.2558,190
23749.221.128.0/1949.221.128.1 to 49.221.159.25449.221.159.2558,190
23849.221.160.0/1949.221.160.1 to 49.221.191.25449.221.191.2558,190
23949.221.192.0/1949.221.192.1 to 49.221.223.25449.221.223.2558,190
24049.221.224.0/1949.221.224.1 to 49.221.255.25449.221.255.2558,190
24149.222.0.0/1949.222.0.1 to 49.222.31.25449.222.31.2558,190
24249.222.32.0/1949.222.32.1 to 49.222.63.25449.222.63.2558,190
24349.222.64.0/1949.222.64.1 to 49.222.95.25449.222.95.2558,190
24449.222.96.0/1949.222.96.1 to 49.222.127.25449.222.127.2558,190
24549.222.128.0/1949.222.128.1 to 49.222.159.25449.222.159.2558,190
24649.222.160.0/1949.222.160.1 to 49.222.191.25449.222.191.2558,190
24749.222.192.0/1949.222.192.1 to 49.222.223.25449.222.223.2558,190
24849.222.224.0/1949.222.224.1 to 49.222.255.25449.222.255.2558,190
24949.223.0.0/1949.223.0.1 to 49.223.31.25449.223.31.2558,190
25049.223.32.0/1949.223.32.1 to 49.223.63.25449.223.63.2558,190
25149.223.64.0/1949.223.64.1 to 49.223.95.25449.223.95.2558,190
25249.223.96.0/1949.223.96.1 to 49.223.127.25449.223.127.2558,190
25349.223.128.0/1949.223.128.1 to 49.223.159.25449.223.159.2558,190
25449.223.160.0/1949.223.160.1 to 49.223.191.25449.223.191.2558,190
25549.223.192.0/1949.223.192.1 to 49.223.223.25449.223.223.2558,190
25649.223.224.0/1949.223.224.1 to 49.223.255.25449.223.255.2558,190

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.