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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.

Network32.192.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
32.192.0.0
Broadcast address
32.255.255.255
First usable
32.192.0.1
Last usable
32.255.255.254
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 20C00000 · Integer 549453824 to 553648127
Reverse DNS zones
192.32.in-addr.arpa
193.32.in-addr.arpa
194.32.in-addr.arpa
195.32.in-addr.arpa
196.32.in-addr.arpa
197.32.in-addr.arpa
198.32.in-addr.arpa
199.32.in-addr.arpa
200.32.in-addr.arpa
201.32.in-addr.arpa
202.32.in-addr.arpa
203.32.in-addr.arpa
204.32.in-addr.arpa
205.32.in-addr.arpa
206.32.in-addr.arpa
207.32.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
Address00100000.11000000.00000000.0000000032.192.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00100000.11000000.00000000.0000000032.192.0.0
Broadcast00100000.11111111.11111111.1111111132.255.255.255
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)

32.192.0.0/10 makes 1,024 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
132.192.0.0/2032.192.0.1 to 32.192.15.25432.192.15.2554,094
232.192.16.0/2032.192.16.1 to 32.192.31.25432.192.31.2554,094
332.192.32.0/2032.192.32.1 to 32.192.47.25432.192.47.2554,094
432.192.48.0/2032.192.48.1 to 32.192.63.25432.192.63.2554,094
532.192.64.0/2032.192.64.1 to 32.192.79.25432.192.79.2554,094
632.192.80.0/2032.192.80.1 to 32.192.95.25432.192.95.2554,094
732.192.96.0/2032.192.96.1 to 32.192.111.25432.192.111.2554,094
832.192.112.0/2032.192.112.1 to 32.192.127.25432.192.127.2554,094
932.192.128.0/2032.192.128.1 to 32.192.143.25432.192.143.2554,094
1032.192.144.0/2032.192.144.1 to 32.192.159.25432.192.159.2554,094
1132.192.160.0/2032.192.160.1 to 32.192.175.25432.192.175.2554,094
1232.192.176.0/2032.192.176.1 to 32.192.191.25432.192.191.2554,094
1332.192.192.0/2032.192.192.1 to 32.192.207.25432.192.207.2554,094
1432.192.208.0/2032.192.208.1 to 32.192.223.25432.192.223.2554,094
1532.192.224.0/2032.192.224.1 to 32.192.239.25432.192.239.2554,094
1632.192.240.0/2032.192.240.1 to 32.192.255.25432.192.255.2554,094
1732.193.0.0/2032.193.0.1 to 32.193.15.25432.193.15.2554,094
1832.193.16.0/2032.193.16.1 to 32.193.31.25432.193.31.2554,094
1932.193.32.0/2032.193.32.1 to 32.193.47.25432.193.47.2554,094
2032.193.48.0/2032.193.48.1 to 32.193.63.25432.193.63.2554,094
2132.193.64.0/2032.193.64.1 to 32.193.79.25432.193.79.2554,094
2232.193.80.0/2032.193.80.1 to 32.193.95.25432.193.95.2554,094
2332.193.96.0/2032.193.96.1 to 32.193.111.25432.193.111.2554,094
2432.193.112.0/2032.193.112.1 to 32.193.127.25432.193.127.2554,094
2532.193.128.0/2032.193.128.1 to 32.193.143.25432.193.143.2554,094
2632.193.144.0/2032.193.144.1 to 32.193.159.25432.193.159.2554,094
2732.193.160.0/2032.193.160.1 to 32.193.175.25432.193.175.2554,094
2832.193.176.0/2032.193.176.1 to 32.193.191.25432.193.191.2554,094
2932.193.192.0/2032.193.192.1 to 32.193.207.25432.193.207.2554,094
3032.193.208.0/2032.193.208.1 to 32.193.223.25432.193.223.2554,094
3132.193.224.0/2032.193.224.1 to 32.193.239.25432.193.239.2554,094
3232.193.240.0/2032.193.240.1 to 32.193.255.25432.193.255.2554,094
3332.194.0.0/2032.194.0.1 to 32.194.15.25432.194.15.2554,094
3432.194.16.0/2032.194.16.1 to 32.194.31.25432.194.31.2554,094
3532.194.32.0/2032.194.32.1 to 32.194.47.25432.194.47.2554,094
3632.194.48.0/2032.194.48.1 to 32.194.63.25432.194.63.2554,094
3732.194.64.0/2032.194.64.1 to 32.194.79.25432.194.79.2554,094
3832.194.80.0/2032.194.80.1 to 32.194.95.25432.194.95.2554,094
3932.194.96.0/2032.194.96.1 to 32.194.111.25432.194.111.2554,094
4032.194.112.0/2032.194.112.1 to 32.194.127.25432.194.127.2554,094
4132.194.128.0/2032.194.128.1 to 32.194.143.25432.194.143.2554,094
4232.194.144.0/2032.194.144.1 to 32.194.159.25432.194.159.2554,094
4332.194.160.0/2032.194.160.1 to 32.194.175.25432.194.175.2554,094
4432.194.176.0/2032.194.176.1 to 32.194.191.25432.194.191.2554,094
4532.194.192.0/2032.194.192.1 to 32.194.207.25432.194.207.2554,094
4632.194.208.0/2032.194.208.1 to 32.194.223.25432.194.223.2554,094
4732.194.224.0/2032.194.224.1 to 32.194.239.25432.194.239.2554,094
4832.194.240.0/2032.194.240.1 to 32.194.255.25432.194.255.2554,094
4932.195.0.0/2032.195.0.1 to 32.195.15.25432.195.15.2554,094
5032.195.16.0/2032.195.16.1 to 32.195.31.25432.195.31.2554,094
5132.195.32.0/2032.195.32.1 to 32.195.47.25432.195.47.2554,094
5232.195.48.0/2032.195.48.1 to 32.195.63.25432.195.63.2554,094
5332.195.64.0/2032.195.64.1 to 32.195.79.25432.195.79.2554,094
5432.195.80.0/2032.195.80.1 to 32.195.95.25432.195.95.2554,094
5532.195.96.0/2032.195.96.1 to 32.195.111.25432.195.111.2554,094
5632.195.112.0/2032.195.112.1 to 32.195.127.25432.195.127.2554,094
5732.195.128.0/2032.195.128.1 to 32.195.143.25432.195.143.2554,094
5832.195.144.0/2032.195.144.1 to 32.195.159.25432.195.159.2554,094
5932.195.160.0/2032.195.160.1 to 32.195.175.25432.195.175.2554,094
6032.195.176.0/2032.195.176.1 to 32.195.191.25432.195.191.2554,094
6132.195.192.0/2032.195.192.1 to 32.195.207.25432.195.207.2554,094
6232.195.208.0/2032.195.208.1 to 32.195.223.25432.195.223.2554,094
6332.195.224.0/2032.195.224.1 to 32.195.239.25432.195.239.2554,094
6432.195.240.0/2032.195.240.1 to 32.195.255.25432.195.255.2554,094
6532.196.0.0/2032.196.0.1 to 32.196.15.25432.196.15.2554,094
6632.196.16.0/2032.196.16.1 to 32.196.31.25432.196.31.2554,094
6732.196.32.0/2032.196.32.1 to 32.196.47.25432.196.47.2554,094
6832.196.48.0/2032.196.48.1 to 32.196.63.25432.196.63.2554,094
6932.196.64.0/2032.196.64.1 to 32.196.79.25432.196.79.2554,094
7032.196.80.0/2032.196.80.1 to 32.196.95.25432.196.95.2554,094
7132.196.96.0/2032.196.96.1 to 32.196.111.25432.196.111.2554,094
7232.196.112.0/2032.196.112.1 to 32.196.127.25432.196.127.2554,094
7332.196.128.0/2032.196.128.1 to 32.196.143.25432.196.143.2554,094
7432.196.144.0/2032.196.144.1 to 32.196.159.25432.196.159.2554,094
7532.196.160.0/2032.196.160.1 to 32.196.175.25432.196.175.2554,094
7632.196.176.0/2032.196.176.1 to 32.196.191.25432.196.191.2554,094
7732.196.192.0/2032.196.192.1 to 32.196.207.25432.196.207.2554,094
7832.196.208.0/2032.196.208.1 to 32.196.223.25432.196.223.2554,094
7932.196.224.0/2032.196.224.1 to 32.196.239.25432.196.239.2554,094
8032.196.240.0/2032.196.240.1 to 32.196.255.25432.196.255.2554,094
8132.197.0.0/2032.197.0.1 to 32.197.15.25432.197.15.2554,094
8232.197.16.0/2032.197.16.1 to 32.197.31.25432.197.31.2554,094
8332.197.32.0/2032.197.32.1 to 32.197.47.25432.197.47.2554,094
8432.197.48.0/2032.197.48.1 to 32.197.63.25432.197.63.2554,094
8532.197.64.0/2032.197.64.1 to 32.197.79.25432.197.79.2554,094
8632.197.80.0/2032.197.80.1 to 32.197.95.25432.197.95.2554,094
8732.197.96.0/2032.197.96.1 to 32.197.111.25432.197.111.2554,094
8832.197.112.0/2032.197.112.1 to 32.197.127.25432.197.127.2554,094
8932.197.128.0/2032.197.128.1 to 32.197.143.25432.197.143.2554,094
9032.197.144.0/2032.197.144.1 to 32.197.159.25432.197.159.2554,094
9132.197.160.0/2032.197.160.1 to 32.197.175.25432.197.175.2554,094
9232.197.176.0/2032.197.176.1 to 32.197.191.25432.197.191.2554,094
9332.197.192.0/2032.197.192.1 to 32.197.207.25432.197.207.2554,094
9432.197.208.0/2032.197.208.1 to 32.197.223.25432.197.223.2554,094
9532.197.224.0/2032.197.224.1 to 32.197.239.25432.197.239.2554,094
9632.197.240.0/2032.197.240.1 to 32.197.255.25432.197.255.2554,094
9732.198.0.0/2032.198.0.1 to 32.198.15.25432.198.15.2554,094
9832.198.16.0/2032.198.16.1 to 32.198.31.25432.198.31.2554,094
9932.198.32.0/2032.198.32.1 to 32.198.47.25432.198.47.2554,094
10032.198.48.0/2032.198.48.1 to 32.198.63.25432.198.63.2554,094
10132.198.64.0/2032.198.64.1 to 32.198.79.25432.198.79.2554,094
10232.198.80.0/2032.198.80.1 to 32.198.95.25432.198.95.2554,094
10332.198.96.0/2032.198.96.1 to 32.198.111.25432.198.111.2554,094
10432.198.112.0/2032.198.112.1 to 32.198.127.25432.198.127.2554,094
10532.198.128.0/2032.198.128.1 to 32.198.143.25432.198.143.2554,094
10632.198.144.0/2032.198.144.1 to 32.198.159.25432.198.159.2554,094
10732.198.160.0/2032.198.160.1 to 32.198.175.25432.198.175.2554,094
10832.198.176.0/2032.198.176.1 to 32.198.191.25432.198.191.2554,094
10932.198.192.0/2032.198.192.1 to 32.198.207.25432.198.207.2554,094
11032.198.208.0/2032.198.208.1 to 32.198.223.25432.198.223.2554,094
11132.198.224.0/2032.198.224.1 to 32.198.239.25432.198.239.2554,094
11232.198.240.0/2032.198.240.1 to 32.198.255.25432.198.255.2554,094
11332.199.0.0/2032.199.0.1 to 32.199.15.25432.199.15.2554,094
11432.199.16.0/2032.199.16.1 to 32.199.31.25432.199.31.2554,094
11532.199.32.0/2032.199.32.1 to 32.199.47.25432.199.47.2554,094
11632.199.48.0/2032.199.48.1 to 32.199.63.25432.199.63.2554,094
11732.199.64.0/2032.199.64.1 to 32.199.79.25432.199.79.2554,094
11832.199.80.0/2032.199.80.1 to 32.199.95.25432.199.95.2554,094
11932.199.96.0/2032.199.96.1 to 32.199.111.25432.199.111.2554,094
12032.199.112.0/2032.199.112.1 to 32.199.127.25432.199.127.2554,094
12132.199.128.0/2032.199.128.1 to 32.199.143.25432.199.143.2554,094
12232.199.144.0/2032.199.144.1 to 32.199.159.25432.199.159.2554,094
12332.199.160.0/2032.199.160.1 to 32.199.175.25432.199.175.2554,094
12432.199.176.0/2032.199.176.1 to 32.199.191.25432.199.191.2554,094
12532.199.192.0/2032.199.192.1 to 32.199.207.25432.199.207.2554,094
12632.199.208.0/2032.199.208.1 to 32.199.223.25432.199.223.2554,094
12732.199.224.0/2032.199.224.1 to 32.199.239.25432.199.239.2554,094
12832.199.240.0/2032.199.240.1 to 32.199.255.25432.199.255.2554,094
12932.200.0.0/2032.200.0.1 to 32.200.15.25432.200.15.2554,094
13032.200.16.0/2032.200.16.1 to 32.200.31.25432.200.31.2554,094
13132.200.32.0/2032.200.32.1 to 32.200.47.25432.200.47.2554,094
13232.200.48.0/2032.200.48.1 to 32.200.63.25432.200.63.2554,094
13332.200.64.0/2032.200.64.1 to 32.200.79.25432.200.79.2554,094
13432.200.80.0/2032.200.80.1 to 32.200.95.25432.200.95.2554,094
13532.200.96.0/2032.200.96.1 to 32.200.111.25432.200.111.2554,094
13632.200.112.0/2032.200.112.1 to 32.200.127.25432.200.127.2554,094
13732.200.128.0/2032.200.128.1 to 32.200.143.25432.200.143.2554,094
13832.200.144.0/2032.200.144.1 to 32.200.159.25432.200.159.2554,094
13932.200.160.0/2032.200.160.1 to 32.200.175.25432.200.175.2554,094
14032.200.176.0/2032.200.176.1 to 32.200.191.25432.200.191.2554,094
14132.200.192.0/2032.200.192.1 to 32.200.207.25432.200.207.2554,094
14232.200.208.0/2032.200.208.1 to 32.200.223.25432.200.223.2554,094
14332.200.224.0/2032.200.224.1 to 32.200.239.25432.200.239.2554,094
14432.200.240.0/2032.200.240.1 to 32.200.255.25432.200.255.2554,094
14532.201.0.0/2032.201.0.1 to 32.201.15.25432.201.15.2554,094
14632.201.16.0/2032.201.16.1 to 32.201.31.25432.201.31.2554,094
14732.201.32.0/2032.201.32.1 to 32.201.47.25432.201.47.2554,094
14832.201.48.0/2032.201.48.1 to 32.201.63.25432.201.63.2554,094
14932.201.64.0/2032.201.64.1 to 32.201.79.25432.201.79.2554,094
15032.201.80.0/2032.201.80.1 to 32.201.95.25432.201.95.2554,094
15132.201.96.0/2032.201.96.1 to 32.201.111.25432.201.111.2554,094
15232.201.112.0/2032.201.112.1 to 32.201.127.25432.201.127.2554,094
15332.201.128.0/2032.201.128.1 to 32.201.143.25432.201.143.2554,094
15432.201.144.0/2032.201.144.1 to 32.201.159.25432.201.159.2554,094
15532.201.160.0/2032.201.160.1 to 32.201.175.25432.201.175.2554,094
15632.201.176.0/2032.201.176.1 to 32.201.191.25432.201.191.2554,094
15732.201.192.0/2032.201.192.1 to 32.201.207.25432.201.207.2554,094
15832.201.208.0/2032.201.208.1 to 32.201.223.25432.201.223.2554,094
15932.201.224.0/2032.201.224.1 to 32.201.239.25432.201.239.2554,094
16032.201.240.0/2032.201.240.1 to 32.201.255.25432.201.255.2554,094
16132.202.0.0/2032.202.0.1 to 32.202.15.25432.202.15.2554,094
16232.202.16.0/2032.202.16.1 to 32.202.31.25432.202.31.2554,094
16332.202.32.0/2032.202.32.1 to 32.202.47.25432.202.47.2554,094
16432.202.48.0/2032.202.48.1 to 32.202.63.25432.202.63.2554,094
16532.202.64.0/2032.202.64.1 to 32.202.79.25432.202.79.2554,094
16632.202.80.0/2032.202.80.1 to 32.202.95.25432.202.95.2554,094
16732.202.96.0/2032.202.96.1 to 32.202.111.25432.202.111.2554,094
16832.202.112.0/2032.202.112.1 to 32.202.127.25432.202.127.2554,094
16932.202.128.0/2032.202.128.1 to 32.202.143.25432.202.143.2554,094
17032.202.144.0/2032.202.144.1 to 32.202.159.25432.202.159.2554,094
17132.202.160.0/2032.202.160.1 to 32.202.175.25432.202.175.2554,094
17232.202.176.0/2032.202.176.1 to 32.202.191.25432.202.191.2554,094
17332.202.192.0/2032.202.192.1 to 32.202.207.25432.202.207.2554,094
17432.202.208.0/2032.202.208.1 to 32.202.223.25432.202.223.2554,094
17532.202.224.0/2032.202.224.1 to 32.202.239.25432.202.239.2554,094
17632.202.240.0/2032.202.240.1 to 32.202.255.25432.202.255.2554,094
17732.203.0.0/2032.203.0.1 to 32.203.15.25432.203.15.2554,094
17832.203.16.0/2032.203.16.1 to 32.203.31.25432.203.31.2554,094
17932.203.32.0/2032.203.32.1 to 32.203.47.25432.203.47.2554,094
18032.203.48.0/2032.203.48.1 to 32.203.63.25432.203.63.2554,094
18132.203.64.0/2032.203.64.1 to 32.203.79.25432.203.79.2554,094
18232.203.80.0/2032.203.80.1 to 32.203.95.25432.203.95.2554,094
18332.203.96.0/2032.203.96.1 to 32.203.111.25432.203.111.2554,094
18432.203.112.0/2032.203.112.1 to 32.203.127.25432.203.127.2554,094
18532.203.128.0/2032.203.128.1 to 32.203.143.25432.203.143.2554,094
18632.203.144.0/2032.203.144.1 to 32.203.159.25432.203.159.2554,094
18732.203.160.0/2032.203.160.1 to 32.203.175.25432.203.175.2554,094
18832.203.176.0/2032.203.176.1 to 32.203.191.25432.203.191.2554,094
18932.203.192.0/2032.203.192.1 to 32.203.207.25432.203.207.2554,094
19032.203.208.0/2032.203.208.1 to 32.203.223.25432.203.223.2554,094
19132.203.224.0/2032.203.224.1 to 32.203.239.25432.203.239.2554,094
19232.203.240.0/2032.203.240.1 to 32.203.255.25432.203.255.2554,094
19332.204.0.0/2032.204.0.1 to 32.204.15.25432.204.15.2554,094
19432.204.16.0/2032.204.16.1 to 32.204.31.25432.204.31.2554,094
19532.204.32.0/2032.204.32.1 to 32.204.47.25432.204.47.2554,094
19632.204.48.0/2032.204.48.1 to 32.204.63.25432.204.63.2554,094
19732.204.64.0/2032.204.64.1 to 32.204.79.25432.204.79.2554,094
19832.204.80.0/2032.204.80.1 to 32.204.95.25432.204.95.2554,094
19932.204.96.0/2032.204.96.1 to 32.204.111.25432.204.111.2554,094
20032.204.112.0/2032.204.112.1 to 32.204.127.25432.204.127.2554,094
20132.204.128.0/2032.204.128.1 to 32.204.143.25432.204.143.2554,094
20232.204.144.0/2032.204.144.1 to 32.204.159.25432.204.159.2554,094
20332.204.160.0/2032.204.160.1 to 32.204.175.25432.204.175.2554,094
20432.204.176.0/2032.204.176.1 to 32.204.191.25432.204.191.2554,094
20532.204.192.0/2032.204.192.1 to 32.204.207.25432.204.207.2554,094
20632.204.208.0/2032.204.208.1 to 32.204.223.25432.204.223.2554,094
20732.204.224.0/2032.204.224.1 to 32.204.239.25432.204.239.2554,094
20832.204.240.0/2032.204.240.1 to 32.204.255.25432.204.255.2554,094
20932.205.0.0/2032.205.0.1 to 32.205.15.25432.205.15.2554,094
21032.205.16.0/2032.205.16.1 to 32.205.31.25432.205.31.2554,094
21132.205.32.0/2032.205.32.1 to 32.205.47.25432.205.47.2554,094
21232.205.48.0/2032.205.48.1 to 32.205.63.25432.205.63.2554,094
21332.205.64.0/2032.205.64.1 to 32.205.79.25432.205.79.2554,094
21432.205.80.0/2032.205.80.1 to 32.205.95.25432.205.95.2554,094
21532.205.96.0/2032.205.96.1 to 32.205.111.25432.205.111.2554,094
21632.205.112.0/2032.205.112.1 to 32.205.127.25432.205.127.2554,094
21732.205.128.0/2032.205.128.1 to 32.205.143.25432.205.143.2554,094
21832.205.144.0/2032.205.144.1 to 32.205.159.25432.205.159.2554,094
21932.205.160.0/2032.205.160.1 to 32.205.175.25432.205.175.2554,094
22032.205.176.0/2032.205.176.1 to 32.205.191.25432.205.191.2554,094
22132.205.192.0/2032.205.192.1 to 32.205.207.25432.205.207.2554,094
22232.205.208.0/2032.205.208.1 to 32.205.223.25432.205.223.2554,094
22332.205.224.0/2032.205.224.1 to 32.205.239.25432.205.239.2554,094
22432.205.240.0/2032.205.240.1 to 32.205.255.25432.205.255.2554,094
22532.206.0.0/2032.206.0.1 to 32.206.15.25432.206.15.2554,094
22632.206.16.0/2032.206.16.1 to 32.206.31.25432.206.31.2554,094
22732.206.32.0/2032.206.32.1 to 32.206.47.25432.206.47.2554,094
22832.206.48.0/2032.206.48.1 to 32.206.63.25432.206.63.2554,094
22932.206.64.0/2032.206.64.1 to 32.206.79.25432.206.79.2554,094
23032.206.80.0/2032.206.80.1 to 32.206.95.25432.206.95.2554,094
23132.206.96.0/2032.206.96.1 to 32.206.111.25432.206.111.2554,094
23232.206.112.0/2032.206.112.1 to 32.206.127.25432.206.127.2554,094
23332.206.128.0/2032.206.128.1 to 32.206.143.25432.206.143.2554,094
23432.206.144.0/2032.206.144.1 to 32.206.159.25432.206.159.2554,094
23532.206.160.0/2032.206.160.1 to 32.206.175.25432.206.175.2554,094
23632.206.176.0/2032.206.176.1 to 32.206.191.25432.206.191.2554,094
23732.206.192.0/2032.206.192.1 to 32.206.207.25432.206.207.2554,094
23832.206.208.0/2032.206.208.1 to 32.206.223.25432.206.223.2554,094
23932.206.224.0/2032.206.224.1 to 32.206.239.25432.206.239.2554,094
24032.206.240.0/2032.206.240.1 to 32.206.255.25432.206.255.2554,094
24132.207.0.0/2032.207.0.1 to 32.207.15.25432.207.15.2554,094
24232.207.16.0/2032.207.16.1 to 32.207.31.25432.207.31.2554,094
24332.207.32.0/2032.207.32.1 to 32.207.47.25432.207.47.2554,094
24432.207.48.0/2032.207.48.1 to 32.207.63.25432.207.63.2554,094
24532.207.64.0/2032.207.64.1 to 32.207.79.25432.207.79.2554,094
24632.207.80.0/2032.207.80.1 to 32.207.95.25432.207.95.2554,094
24732.207.96.0/2032.207.96.1 to 32.207.111.25432.207.111.2554,094
24832.207.112.0/2032.207.112.1 to 32.207.127.25432.207.127.2554,094
24932.207.128.0/2032.207.128.1 to 32.207.143.25432.207.143.2554,094
25032.207.144.0/2032.207.144.1 to 32.207.159.25432.207.159.2554,094
25132.207.160.0/2032.207.160.1 to 32.207.175.25432.207.175.2554,094
25232.207.176.0/2032.207.176.1 to 32.207.191.25432.207.191.2554,094
25332.207.192.0/2032.207.192.1 to 32.207.207.25432.207.207.2554,094
25432.207.208.0/2032.207.208.1 to 32.207.223.25432.207.223.2554,094
25532.207.224.0/2032.207.224.1 to 32.207.239.25432.207.239.2554,094
25632.207.240.0/2032.207.240.1 to 32.207.255.25432.207.255.2554,094

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.