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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/20
/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 1,024 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
149.192.0.0/2049.192.0.1 to 49.192.15.25449.192.15.2554,094
249.192.16.0/2049.192.16.1 to 49.192.31.25449.192.31.2554,094
349.192.32.0/2049.192.32.1 to 49.192.47.25449.192.47.2554,094
449.192.48.0/2049.192.48.1 to 49.192.63.25449.192.63.2554,094
549.192.64.0/2049.192.64.1 to 49.192.79.25449.192.79.2554,094
649.192.80.0/2049.192.80.1 to 49.192.95.25449.192.95.2554,094
749.192.96.0/2049.192.96.1 to 49.192.111.25449.192.111.2554,094
849.192.112.0/2049.192.112.1 to 49.192.127.25449.192.127.2554,094
949.192.128.0/2049.192.128.1 to 49.192.143.25449.192.143.2554,094
1049.192.144.0/2049.192.144.1 to 49.192.159.25449.192.159.2554,094
1149.192.160.0/2049.192.160.1 to 49.192.175.25449.192.175.2554,094
1249.192.176.0/2049.192.176.1 to 49.192.191.25449.192.191.2554,094
1349.192.192.0/2049.192.192.1 to 49.192.207.25449.192.207.2554,094
1449.192.208.0/2049.192.208.1 to 49.192.223.25449.192.223.2554,094
1549.192.224.0/2049.192.224.1 to 49.192.239.25449.192.239.2554,094
1649.192.240.0/2049.192.240.1 to 49.192.255.25449.192.255.2554,094
1749.193.0.0/2049.193.0.1 to 49.193.15.25449.193.15.2554,094
1849.193.16.0/2049.193.16.1 to 49.193.31.25449.193.31.2554,094
1949.193.32.0/2049.193.32.1 to 49.193.47.25449.193.47.2554,094
2049.193.48.0/2049.193.48.1 to 49.193.63.25449.193.63.2554,094
2149.193.64.0/2049.193.64.1 to 49.193.79.25449.193.79.2554,094
2249.193.80.0/2049.193.80.1 to 49.193.95.25449.193.95.2554,094
2349.193.96.0/2049.193.96.1 to 49.193.111.25449.193.111.2554,094
2449.193.112.0/2049.193.112.1 to 49.193.127.25449.193.127.2554,094
2549.193.128.0/2049.193.128.1 to 49.193.143.25449.193.143.2554,094
2649.193.144.0/2049.193.144.1 to 49.193.159.25449.193.159.2554,094
2749.193.160.0/2049.193.160.1 to 49.193.175.25449.193.175.2554,094
2849.193.176.0/2049.193.176.1 to 49.193.191.25449.193.191.2554,094
2949.193.192.0/2049.193.192.1 to 49.193.207.25449.193.207.2554,094
3049.193.208.0/2049.193.208.1 to 49.193.223.25449.193.223.2554,094
3149.193.224.0/2049.193.224.1 to 49.193.239.25449.193.239.2554,094
3249.193.240.0/2049.193.240.1 to 49.193.255.25449.193.255.2554,094
3349.194.0.0/2049.194.0.1 to 49.194.15.25449.194.15.2554,094
3449.194.16.0/2049.194.16.1 to 49.194.31.25449.194.31.2554,094
3549.194.32.0/2049.194.32.1 to 49.194.47.25449.194.47.2554,094
3649.194.48.0/2049.194.48.1 to 49.194.63.25449.194.63.2554,094
3749.194.64.0/2049.194.64.1 to 49.194.79.25449.194.79.2554,094
3849.194.80.0/2049.194.80.1 to 49.194.95.25449.194.95.2554,094
3949.194.96.0/2049.194.96.1 to 49.194.111.25449.194.111.2554,094
4049.194.112.0/2049.194.112.1 to 49.194.127.25449.194.127.2554,094
4149.194.128.0/2049.194.128.1 to 49.194.143.25449.194.143.2554,094
4249.194.144.0/2049.194.144.1 to 49.194.159.25449.194.159.2554,094
4349.194.160.0/2049.194.160.1 to 49.194.175.25449.194.175.2554,094
4449.194.176.0/2049.194.176.1 to 49.194.191.25449.194.191.2554,094
4549.194.192.0/2049.194.192.1 to 49.194.207.25449.194.207.2554,094
4649.194.208.0/2049.194.208.1 to 49.194.223.25449.194.223.2554,094
4749.194.224.0/2049.194.224.1 to 49.194.239.25449.194.239.2554,094
4849.194.240.0/2049.194.240.1 to 49.194.255.25449.194.255.2554,094
4949.195.0.0/2049.195.0.1 to 49.195.15.25449.195.15.2554,094
5049.195.16.0/2049.195.16.1 to 49.195.31.25449.195.31.2554,094
5149.195.32.0/2049.195.32.1 to 49.195.47.25449.195.47.2554,094
5249.195.48.0/2049.195.48.1 to 49.195.63.25449.195.63.2554,094
5349.195.64.0/2049.195.64.1 to 49.195.79.25449.195.79.2554,094
5449.195.80.0/2049.195.80.1 to 49.195.95.25449.195.95.2554,094
5549.195.96.0/2049.195.96.1 to 49.195.111.25449.195.111.2554,094
5649.195.112.0/2049.195.112.1 to 49.195.127.25449.195.127.2554,094
5749.195.128.0/2049.195.128.1 to 49.195.143.25449.195.143.2554,094
5849.195.144.0/2049.195.144.1 to 49.195.159.25449.195.159.2554,094
5949.195.160.0/2049.195.160.1 to 49.195.175.25449.195.175.2554,094
6049.195.176.0/2049.195.176.1 to 49.195.191.25449.195.191.2554,094
6149.195.192.0/2049.195.192.1 to 49.195.207.25449.195.207.2554,094
6249.195.208.0/2049.195.208.1 to 49.195.223.25449.195.223.2554,094
6349.195.224.0/2049.195.224.1 to 49.195.239.25449.195.239.2554,094
6449.195.240.0/2049.195.240.1 to 49.195.255.25449.195.255.2554,094
6549.196.0.0/2049.196.0.1 to 49.196.15.25449.196.15.2554,094
6649.196.16.0/2049.196.16.1 to 49.196.31.25449.196.31.2554,094
6749.196.32.0/2049.196.32.1 to 49.196.47.25449.196.47.2554,094
6849.196.48.0/2049.196.48.1 to 49.196.63.25449.196.63.2554,094
6949.196.64.0/2049.196.64.1 to 49.196.79.25449.196.79.2554,094
7049.196.80.0/2049.196.80.1 to 49.196.95.25449.196.95.2554,094
7149.196.96.0/2049.196.96.1 to 49.196.111.25449.196.111.2554,094
7249.196.112.0/2049.196.112.1 to 49.196.127.25449.196.127.2554,094
7349.196.128.0/2049.196.128.1 to 49.196.143.25449.196.143.2554,094
7449.196.144.0/2049.196.144.1 to 49.196.159.25449.196.159.2554,094
7549.196.160.0/2049.196.160.1 to 49.196.175.25449.196.175.2554,094
7649.196.176.0/2049.196.176.1 to 49.196.191.25449.196.191.2554,094
7749.196.192.0/2049.196.192.1 to 49.196.207.25449.196.207.2554,094
7849.196.208.0/2049.196.208.1 to 49.196.223.25449.196.223.2554,094
7949.196.224.0/2049.196.224.1 to 49.196.239.25449.196.239.2554,094
8049.196.240.0/2049.196.240.1 to 49.196.255.25449.196.255.2554,094
8149.197.0.0/2049.197.0.1 to 49.197.15.25449.197.15.2554,094
8249.197.16.0/2049.197.16.1 to 49.197.31.25449.197.31.2554,094
8349.197.32.0/2049.197.32.1 to 49.197.47.25449.197.47.2554,094
8449.197.48.0/2049.197.48.1 to 49.197.63.25449.197.63.2554,094
8549.197.64.0/2049.197.64.1 to 49.197.79.25449.197.79.2554,094
8649.197.80.0/2049.197.80.1 to 49.197.95.25449.197.95.2554,094
8749.197.96.0/2049.197.96.1 to 49.197.111.25449.197.111.2554,094
8849.197.112.0/2049.197.112.1 to 49.197.127.25449.197.127.2554,094
8949.197.128.0/2049.197.128.1 to 49.197.143.25449.197.143.2554,094
9049.197.144.0/2049.197.144.1 to 49.197.159.25449.197.159.2554,094
9149.197.160.0/2049.197.160.1 to 49.197.175.25449.197.175.2554,094
9249.197.176.0/2049.197.176.1 to 49.197.191.25449.197.191.2554,094
9349.197.192.0/2049.197.192.1 to 49.197.207.25449.197.207.2554,094
9449.197.208.0/2049.197.208.1 to 49.197.223.25449.197.223.2554,094
9549.197.224.0/2049.197.224.1 to 49.197.239.25449.197.239.2554,094
9649.197.240.0/2049.197.240.1 to 49.197.255.25449.197.255.2554,094
9749.198.0.0/2049.198.0.1 to 49.198.15.25449.198.15.2554,094
9849.198.16.0/2049.198.16.1 to 49.198.31.25449.198.31.2554,094
9949.198.32.0/2049.198.32.1 to 49.198.47.25449.198.47.2554,094
10049.198.48.0/2049.198.48.1 to 49.198.63.25449.198.63.2554,094
10149.198.64.0/2049.198.64.1 to 49.198.79.25449.198.79.2554,094
10249.198.80.0/2049.198.80.1 to 49.198.95.25449.198.95.2554,094
10349.198.96.0/2049.198.96.1 to 49.198.111.25449.198.111.2554,094
10449.198.112.0/2049.198.112.1 to 49.198.127.25449.198.127.2554,094
10549.198.128.0/2049.198.128.1 to 49.198.143.25449.198.143.2554,094
10649.198.144.0/2049.198.144.1 to 49.198.159.25449.198.159.2554,094
10749.198.160.0/2049.198.160.1 to 49.198.175.25449.198.175.2554,094
10849.198.176.0/2049.198.176.1 to 49.198.191.25449.198.191.2554,094
10949.198.192.0/2049.198.192.1 to 49.198.207.25449.198.207.2554,094
11049.198.208.0/2049.198.208.1 to 49.198.223.25449.198.223.2554,094
11149.198.224.0/2049.198.224.1 to 49.198.239.25449.198.239.2554,094
11249.198.240.0/2049.198.240.1 to 49.198.255.25449.198.255.2554,094
11349.199.0.0/2049.199.0.1 to 49.199.15.25449.199.15.2554,094
11449.199.16.0/2049.199.16.1 to 49.199.31.25449.199.31.2554,094
11549.199.32.0/2049.199.32.1 to 49.199.47.25449.199.47.2554,094
11649.199.48.0/2049.199.48.1 to 49.199.63.25449.199.63.2554,094
11749.199.64.0/2049.199.64.1 to 49.199.79.25449.199.79.2554,094
11849.199.80.0/2049.199.80.1 to 49.199.95.25449.199.95.2554,094
11949.199.96.0/2049.199.96.1 to 49.199.111.25449.199.111.2554,094
12049.199.112.0/2049.199.112.1 to 49.199.127.25449.199.127.2554,094
12149.199.128.0/2049.199.128.1 to 49.199.143.25449.199.143.2554,094
12249.199.144.0/2049.199.144.1 to 49.199.159.25449.199.159.2554,094
12349.199.160.0/2049.199.160.1 to 49.199.175.25449.199.175.2554,094
12449.199.176.0/2049.199.176.1 to 49.199.191.25449.199.191.2554,094
12549.199.192.0/2049.199.192.1 to 49.199.207.25449.199.207.2554,094
12649.199.208.0/2049.199.208.1 to 49.199.223.25449.199.223.2554,094
12749.199.224.0/2049.199.224.1 to 49.199.239.25449.199.239.2554,094
12849.199.240.0/2049.199.240.1 to 49.199.255.25449.199.255.2554,094
12949.200.0.0/2049.200.0.1 to 49.200.15.25449.200.15.2554,094
13049.200.16.0/2049.200.16.1 to 49.200.31.25449.200.31.2554,094
13149.200.32.0/2049.200.32.1 to 49.200.47.25449.200.47.2554,094
13249.200.48.0/2049.200.48.1 to 49.200.63.25449.200.63.2554,094
13349.200.64.0/2049.200.64.1 to 49.200.79.25449.200.79.2554,094
13449.200.80.0/2049.200.80.1 to 49.200.95.25449.200.95.2554,094
13549.200.96.0/2049.200.96.1 to 49.200.111.25449.200.111.2554,094
13649.200.112.0/2049.200.112.1 to 49.200.127.25449.200.127.2554,094
13749.200.128.0/2049.200.128.1 to 49.200.143.25449.200.143.2554,094
13849.200.144.0/2049.200.144.1 to 49.200.159.25449.200.159.2554,094
13949.200.160.0/2049.200.160.1 to 49.200.175.25449.200.175.2554,094
14049.200.176.0/2049.200.176.1 to 49.200.191.25449.200.191.2554,094
14149.200.192.0/2049.200.192.1 to 49.200.207.25449.200.207.2554,094
14249.200.208.0/2049.200.208.1 to 49.200.223.25449.200.223.2554,094
14349.200.224.0/2049.200.224.1 to 49.200.239.25449.200.239.2554,094
14449.200.240.0/2049.200.240.1 to 49.200.255.25449.200.255.2554,094
14549.201.0.0/2049.201.0.1 to 49.201.15.25449.201.15.2554,094
14649.201.16.0/2049.201.16.1 to 49.201.31.25449.201.31.2554,094
14749.201.32.0/2049.201.32.1 to 49.201.47.25449.201.47.2554,094
14849.201.48.0/2049.201.48.1 to 49.201.63.25449.201.63.2554,094
14949.201.64.0/2049.201.64.1 to 49.201.79.25449.201.79.2554,094
15049.201.80.0/2049.201.80.1 to 49.201.95.25449.201.95.2554,094
15149.201.96.0/2049.201.96.1 to 49.201.111.25449.201.111.2554,094
15249.201.112.0/2049.201.112.1 to 49.201.127.25449.201.127.2554,094
15349.201.128.0/2049.201.128.1 to 49.201.143.25449.201.143.2554,094
15449.201.144.0/2049.201.144.1 to 49.201.159.25449.201.159.2554,094
15549.201.160.0/2049.201.160.1 to 49.201.175.25449.201.175.2554,094
15649.201.176.0/2049.201.176.1 to 49.201.191.25449.201.191.2554,094
15749.201.192.0/2049.201.192.1 to 49.201.207.25449.201.207.2554,094
15849.201.208.0/2049.201.208.1 to 49.201.223.25449.201.223.2554,094
15949.201.224.0/2049.201.224.1 to 49.201.239.25449.201.239.2554,094
16049.201.240.0/2049.201.240.1 to 49.201.255.25449.201.255.2554,094
16149.202.0.0/2049.202.0.1 to 49.202.15.25449.202.15.2554,094
16249.202.16.0/2049.202.16.1 to 49.202.31.25449.202.31.2554,094
16349.202.32.0/2049.202.32.1 to 49.202.47.25449.202.47.2554,094
16449.202.48.0/2049.202.48.1 to 49.202.63.25449.202.63.2554,094
16549.202.64.0/2049.202.64.1 to 49.202.79.25449.202.79.2554,094
16649.202.80.0/2049.202.80.1 to 49.202.95.25449.202.95.2554,094
16749.202.96.0/2049.202.96.1 to 49.202.111.25449.202.111.2554,094
16849.202.112.0/2049.202.112.1 to 49.202.127.25449.202.127.2554,094
16949.202.128.0/2049.202.128.1 to 49.202.143.25449.202.143.2554,094
17049.202.144.0/2049.202.144.1 to 49.202.159.25449.202.159.2554,094
17149.202.160.0/2049.202.160.1 to 49.202.175.25449.202.175.2554,094
17249.202.176.0/2049.202.176.1 to 49.202.191.25449.202.191.2554,094
17349.202.192.0/2049.202.192.1 to 49.202.207.25449.202.207.2554,094
17449.202.208.0/2049.202.208.1 to 49.202.223.25449.202.223.2554,094
17549.202.224.0/2049.202.224.1 to 49.202.239.25449.202.239.2554,094
17649.202.240.0/2049.202.240.1 to 49.202.255.25449.202.255.2554,094
17749.203.0.0/2049.203.0.1 to 49.203.15.25449.203.15.2554,094
17849.203.16.0/2049.203.16.1 to 49.203.31.25449.203.31.2554,094
17949.203.32.0/2049.203.32.1 to 49.203.47.25449.203.47.2554,094
18049.203.48.0/2049.203.48.1 to 49.203.63.25449.203.63.2554,094
18149.203.64.0/2049.203.64.1 to 49.203.79.25449.203.79.2554,094
18249.203.80.0/2049.203.80.1 to 49.203.95.25449.203.95.2554,094
18349.203.96.0/2049.203.96.1 to 49.203.111.25449.203.111.2554,094
18449.203.112.0/2049.203.112.1 to 49.203.127.25449.203.127.2554,094
18549.203.128.0/2049.203.128.1 to 49.203.143.25449.203.143.2554,094
18649.203.144.0/2049.203.144.1 to 49.203.159.25449.203.159.2554,094
18749.203.160.0/2049.203.160.1 to 49.203.175.25449.203.175.2554,094
18849.203.176.0/2049.203.176.1 to 49.203.191.25449.203.191.2554,094
18949.203.192.0/2049.203.192.1 to 49.203.207.25449.203.207.2554,094
19049.203.208.0/2049.203.208.1 to 49.203.223.25449.203.223.2554,094
19149.203.224.0/2049.203.224.1 to 49.203.239.25449.203.239.2554,094
19249.203.240.0/2049.203.240.1 to 49.203.255.25449.203.255.2554,094
19349.204.0.0/2049.204.0.1 to 49.204.15.25449.204.15.2554,094
19449.204.16.0/2049.204.16.1 to 49.204.31.25449.204.31.2554,094
19549.204.32.0/2049.204.32.1 to 49.204.47.25449.204.47.2554,094
19649.204.48.0/2049.204.48.1 to 49.204.63.25449.204.63.2554,094
19749.204.64.0/2049.204.64.1 to 49.204.79.25449.204.79.2554,094
19849.204.80.0/2049.204.80.1 to 49.204.95.25449.204.95.2554,094
19949.204.96.0/2049.204.96.1 to 49.204.111.25449.204.111.2554,094
20049.204.112.0/2049.204.112.1 to 49.204.127.25449.204.127.2554,094
20149.204.128.0/2049.204.128.1 to 49.204.143.25449.204.143.2554,094
20249.204.144.0/2049.204.144.1 to 49.204.159.25449.204.159.2554,094
20349.204.160.0/2049.204.160.1 to 49.204.175.25449.204.175.2554,094
20449.204.176.0/2049.204.176.1 to 49.204.191.25449.204.191.2554,094
20549.204.192.0/2049.204.192.1 to 49.204.207.25449.204.207.2554,094
20649.204.208.0/2049.204.208.1 to 49.204.223.25449.204.223.2554,094
20749.204.224.0/2049.204.224.1 to 49.204.239.25449.204.239.2554,094
20849.204.240.0/2049.204.240.1 to 49.204.255.25449.204.255.2554,094
20949.205.0.0/2049.205.0.1 to 49.205.15.25449.205.15.2554,094
21049.205.16.0/2049.205.16.1 to 49.205.31.25449.205.31.2554,094
21149.205.32.0/2049.205.32.1 to 49.205.47.25449.205.47.2554,094
21249.205.48.0/2049.205.48.1 to 49.205.63.25449.205.63.2554,094
21349.205.64.0/2049.205.64.1 to 49.205.79.25449.205.79.2554,094
21449.205.80.0/2049.205.80.1 to 49.205.95.25449.205.95.2554,094
21549.205.96.0/2049.205.96.1 to 49.205.111.25449.205.111.2554,094
21649.205.112.0/2049.205.112.1 to 49.205.127.25449.205.127.2554,094
21749.205.128.0/2049.205.128.1 to 49.205.143.25449.205.143.2554,094
21849.205.144.0/2049.205.144.1 to 49.205.159.25449.205.159.2554,094
21949.205.160.0/2049.205.160.1 to 49.205.175.25449.205.175.2554,094
22049.205.176.0/2049.205.176.1 to 49.205.191.25449.205.191.2554,094
22149.205.192.0/2049.205.192.1 to 49.205.207.25449.205.207.2554,094
22249.205.208.0/2049.205.208.1 to 49.205.223.25449.205.223.2554,094
22349.205.224.0/2049.205.224.1 to 49.205.239.25449.205.239.2554,094
22449.205.240.0/2049.205.240.1 to 49.205.255.25449.205.255.2554,094
22549.206.0.0/2049.206.0.1 to 49.206.15.25449.206.15.2554,094
22649.206.16.0/2049.206.16.1 to 49.206.31.25449.206.31.2554,094
22749.206.32.0/2049.206.32.1 to 49.206.47.25449.206.47.2554,094
22849.206.48.0/2049.206.48.1 to 49.206.63.25449.206.63.2554,094
22949.206.64.0/2049.206.64.1 to 49.206.79.25449.206.79.2554,094
23049.206.80.0/2049.206.80.1 to 49.206.95.25449.206.95.2554,094
23149.206.96.0/2049.206.96.1 to 49.206.111.25449.206.111.2554,094
23249.206.112.0/2049.206.112.1 to 49.206.127.25449.206.127.2554,094
23349.206.128.0/2049.206.128.1 to 49.206.143.25449.206.143.2554,094
23449.206.144.0/2049.206.144.1 to 49.206.159.25449.206.159.2554,094
23549.206.160.0/2049.206.160.1 to 49.206.175.25449.206.175.2554,094
23649.206.176.0/2049.206.176.1 to 49.206.191.25449.206.191.2554,094
23749.206.192.0/2049.206.192.1 to 49.206.207.25449.206.207.2554,094
23849.206.208.0/2049.206.208.1 to 49.206.223.25449.206.223.2554,094
23949.206.224.0/2049.206.224.1 to 49.206.239.25449.206.239.2554,094
24049.206.240.0/2049.206.240.1 to 49.206.255.25449.206.255.2554,094
24149.207.0.0/2049.207.0.1 to 49.207.15.25449.207.15.2554,094
24249.207.16.0/2049.207.16.1 to 49.207.31.25449.207.31.2554,094
24349.207.32.0/2049.207.32.1 to 49.207.47.25449.207.47.2554,094
24449.207.48.0/2049.207.48.1 to 49.207.63.25449.207.63.2554,094
24549.207.64.0/2049.207.64.1 to 49.207.79.25449.207.79.2554,094
24649.207.80.0/2049.207.80.1 to 49.207.95.25449.207.95.2554,094
24749.207.96.0/2049.207.96.1 to 49.207.111.25449.207.111.2554,094
24849.207.112.0/2049.207.112.1 to 49.207.127.25449.207.127.2554,094
24949.207.128.0/2049.207.128.1 to 49.207.143.25449.207.143.2554,094
25049.207.144.0/2049.207.144.1 to 49.207.159.25449.207.159.2554,094
25149.207.160.0/2049.207.160.1 to 49.207.175.25449.207.175.2554,094
25249.207.176.0/2049.207.176.1 to 49.207.191.25449.207.191.2554,094
25349.207.192.0/2049.207.192.1 to 49.207.207.25449.207.207.2554,094
25449.207.208.0/2049.207.208.1 to 49.207.223.25449.207.223.2554,094
25549.207.224.0/2049.207.224.1 to 49.207.239.25449.207.239.2554,094
25649.207.240.0/2049.207.240.1 to 49.207.255.25449.207.255.2554,094

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.