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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/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)

32.192.0.0/10 makes 512 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
132.192.0.0/1932.192.0.1 to 32.192.31.25432.192.31.2558,190
232.192.32.0/1932.192.32.1 to 32.192.63.25432.192.63.2558,190
332.192.64.0/1932.192.64.1 to 32.192.95.25432.192.95.2558,190
432.192.96.0/1932.192.96.1 to 32.192.127.25432.192.127.2558,190
532.192.128.0/1932.192.128.1 to 32.192.159.25432.192.159.2558,190
632.192.160.0/1932.192.160.1 to 32.192.191.25432.192.191.2558,190
732.192.192.0/1932.192.192.1 to 32.192.223.25432.192.223.2558,190
832.192.224.0/1932.192.224.1 to 32.192.255.25432.192.255.2558,190
932.193.0.0/1932.193.0.1 to 32.193.31.25432.193.31.2558,190
1032.193.32.0/1932.193.32.1 to 32.193.63.25432.193.63.2558,190
1132.193.64.0/1932.193.64.1 to 32.193.95.25432.193.95.2558,190
1232.193.96.0/1932.193.96.1 to 32.193.127.25432.193.127.2558,190
1332.193.128.0/1932.193.128.1 to 32.193.159.25432.193.159.2558,190
1432.193.160.0/1932.193.160.1 to 32.193.191.25432.193.191.2558,190
1532.193.192.0/1932.193.192.1 to 32.193.223.25432.193.223.2558,190
1632.193.224.0/1932.193.224.1 to 32.193.255.25432.193.255.2558,190
1732.194.0.0/1932.194.0.1 to 32.194.31.25432.194.31.2558,190
1832.194.32.0/1932.194.32.1 to 32.194.63.25432.194.63.2558,190
1932.194.64.0/1932.194.64.1 to 32.194.95.25432.194.95.2558,190
2032.194.96.0/1932.194.96.1 to 32.194.127.25432.194.127.2558,190
2132.194.128.0/1932.194.128.1 to 32.194.159.25432.194.159.2558,190
2232.194.160.0/1932.194.160.1 to 32.194.191.25432.194.191.2558,190
2332.194.192.0/1932.194.192.1 to 32.194.223.25432.194.223.2558,190
2432.194.224.0/1932.194.224.1 to 32.194.255.25432.194.255.2558,190
2532.195.0.0/1932.195.0.1 to 32.195.31.25432.195.31.2558,190
2632.195.32.0/1932.195.32.1 to 32.195.63.25432.195.63.2558,190
2732.195.64.0/1932.195.64.1 to 32.195.95.25432.195.95.2558,190
2832.195.96.0/1932.195.96.1 to 32.195.127.25432.195.127.2558,190
2932.195.128.0/1932.195.128.1 to 32.195.159.25432.195.159.2558,190
3032.195.160.0/1932.195.160.1 to 32.195.191.25432.195.191.2558,190
3132.195.192.0/1932.195.192.1 to 32.195.223.25432.195.223.2558,190
3232.195.224.0/1932.195.224.1 to 32.195.255.25432.195.255.2558,190
3332.196.0.0/1932.196.0.1 to 32.196.31.25432.196.31.2558,190
3432.196.32.0/1932.196.32.1 to 32.196.63.25432.196.63.2558,190
3532.196.64.0/1932.196.64.1 to 32.196.95.25432.196.95.2558,190
3632.196.96.0/1932.196.96.1 to 32.196.127.25432.196.127.2558,190
3732.196.128.0/1932.196.128.1 to 32.196.159.25432.196.159.2558,190
3832.196.160.0/1932.196.160.1 to 32.196.191.25432.196.191.2558,190
3932.196.192.0/1932.196.192.1 to 32.196.223.25432.196.223.2558,190
4032.196.224.0/1932.196.224.1 to 32.196.255.25432.196.255.2558,190
4132.197.0.0/1932.197.0.1 to 32.197.31.25432.197.31.2558,190
4232.197.32.0/1932.197.32.1 to 32.197.63.25432.197.63.2558,190
4332.197.64.0/1932.197.64.1 to 32.197.95.25432.197.95.2558,190
4432.197.96.0/1932.197.96.1 to 32.197.127.25432.197.127.2558,190
4532.197.128.0/1932.197.128.1 to 32.197.159.25432.197.159.2558,190
4632.197.160.0/1932.197.160.1 to 32.197.191.25432.197.191.2558,190
4732.197.192.0/1932.197.192.1 to 32.197.223.25432.197.223.2558,190
4832.197.224.0/1932.197.224.1 to 32.197.255.25432.197.255.2558,190
4932.198.0.0/1932.198.0.1 to 32.198.31.25432.198.31.2558,190
5032.198.32.0/1932.198.32.1 to 32.198.63.25432.198.63.2558,190
5132.198.64.0/1932.198.64.1 to 32.198.95.25432.198.95.2558,190
5232.198.96.0/1932.198.96.1 to 32.198.127.25432.198.127.2558,190
5332.198.128.0/1932.198.128.1 to 32.198.159.25432.198.159.2558,190
5432.198.160.0/1932.198.160.1 to 32.198.191.25432.198.191.2558,190
5532.198.192.0/1932.198.192.1 to 32.198.223.25432.198.223.2558,190
5632.198.224.0/1932.198.224.1 to 32.198.255.25432.198.255.2558,190
5732.199.0.0/1932.199.0.1 to 32.199.31.25432.199.31.2558,190
5832.199.32.0/1932.199.32.1 to 32.199.63.25432.199.63.2558,190
5932.199.64.0/1932.199.64.1 to 32.199.95.25432.199.95.2558,190
6032.199.96.0/1932.199.96.1 to 32.199.127.25432.199.127.2558,190
6132.199.128.0/1932.199.128.1 to 32.199.159.25432.199.159.2558,190
6232.199.160.0/1932.199.160.1 to 32.199.191.25432.199.191.2558,190
6332.199.192.0/1932.199.192.1 to 32.199.223.25432.199.223.2558,190
6432.199.224.0/1932.199.224.1 to 32.199.255.25432.199.255.2558,190
6532.200.0.0/1932.200.0.1 to 32.200.31.25432.200.31.2558,190
6632.200.32.0/1932.200.32.1 to 32.200.63.25432.200.63.2558,190
6732.200.64.0/1932.200.64.1 to 32.200.95.25432.200.95.2558,190
6832.200.96.0/1932.200.96.1 to 32.200.127.25432.200.127.2558,190
6932.200.128.0/1932.200.128.1 to 32.200.159.25432.200.159.2558,190
7032.200.160.0/1932.200.160.1 to 32.200.191.25432.200.191.2558,190
7132.200.192.0/1932.200.192.1 to 32.200.223.25432.200.223.2558,190
7232.200.224.0/1932.200.224.1 to 32.200.255.25432.200.255.2558,190
7332.201.0.0/1932.201.0.1 to 32.201.31.25432.201.31.2558,190
7432.201.32.0/1932.201.32.1 to 32.201.63.25432.201.63.2558,190
7532.201.64.0/1932.201.64.1 to 32.201.95.25432.201.95.2558,190
7632.201.96.0/1932.201.96.1 to 32.201.127.25432.201.127.2558,190
7732.201.128.0/1932.201.128.1 to 32.201.159.25432.201.159.2558,190
7832.201.160.0/1932.201.160.1 to 32.201.191.25432.201.191.2558,190
7932.201.192.0/1932.201.192.1 to 32.201.223.25432.201.223.2558,190
8032.201.224.0/1932.201.224.1 to 32.201.255.25432.201.255.2558,190
8132.202.0.0/1932.202.0.1 to 32.202.31.25432.202.31.2558,190
8232.202.32.0/1932.202.32.1 to 32.202.63.25432.202.63.2558,190
8332.202.64.0/1932.202.64.1 to 32.202.95.25432.202.95.2558,190
8432.202.96.0/1932.202.96.1 to 32.202.127.25432.202.127.2558,190
8532.202.128.0/1932.202.128.1 to 32.202.159.25432.202.159.2558,190
8632.202.160.0/1932.202.160.1 to 32.202.191.25432.202.191.2558,190
8732.202.192.0/1932.202.192.1 to 32.202.223.25432.202.223.2558,190
8832.202.224.0/1932.202.224.1 to 32.202.255.25432.202.255.2558,190
8932.203.0.0/1932.203.0.1 to 32.203.31.25432.203.31.2558,190
9032.203.32.0/1932.203.32.1 to 32.203.63.25432.203.63.2558,190
9132.203.64.0/1932.203.64.1 to 32.203.95.25432.203.95.2558,190
9232.203.96.0/1932.203.96.1 to 32.203.127.25432.203.127.2558,190
9332.203.128.0/1932.203.128.1 to 32.203.159.25432.203.159.2558,190
9432.203.160.0/1932.203.160.1 to 32.203.191.25432.203.191.2558,190
9532.203.192.0/1932.203.192.1 to 32.203.223.25432.203.223.2558,190
9632.203.224.0/1932.203.224.1 to 32.203.255.25432.203.255.2558,190
9732.204.0.0/1932.204.0.1 to 32.204.31.25432.204.31.2558,190
9832.204.32.0/1932.204.32.1 to 32.204.63.25432.204.63.2558,190
9932.204.64.0/1932.204.64.1 to 32.204.95.25432.204.95.2558,190
10032.204.96.0/1932.204.96.1 to 32.204.127.25432.204.127.2558,190
10132.204.128.0/1932.204.128.1 to 32.204.159.25432.204.159.2558,190
10232.204.160.0/1932.204.160.1 to 32.204.191.25432.204.191.2558,190
10332.204.192.0/1932.204.192.1 to 32.204.223.25432.204.223.2558,190
10432.204.224.0/1932.204.224.1 to 32.204.255.25432.204.255.2558,190
10532.205.0.0/1932.205.0.1 to 32.205.31.25432.205.31.2558,190
10632.205.32.0/1932.205.32.1 to 32.205.63.25432.205.63.2558,190
10732.205.64.0/1932.205.64.1 to 32.205.95.25432.205.95.2558,190
10832.205.96.0/1932.205.96.1 to 32.205.127.25432.205.127.2558,190
10932.205.128.0/1932.205.128.1 to 32.205.159.25432.205.159.2558,190
11032.205.160.0/1932.205.160.1 to 32.205.191.25432.205.191.2558,190
11132.205.192.0/1932.205.192.1 to 32.205.223.25432.205.223.2558,190
11232.205.224.0/1932.205.224.1 to 32.205.255.25432.205.255.2558,190
11332.206.0.0/1932.206.0.1 to 32.206.31.25432.206.31.2558,190
11432.206.32.0/1932.206.32.1 to 32.206.63.25432.206.63.2558,190
11532.206.64.0/1932.206.64.1 to 32.206.95.25432.206.95.2558,190
11632.206.96.0/1932.206.96.1 to 32.206.127.25432.206.127.2558,190
11732.206.128.0/1932.206.128.1 to 32.206.159.25432.206.159.2558,190
11832.206.160.0/1932.206.160.1 to 32.206.191.25432.206.191.2558,190
11932.206.192.0/1932.206.192.1 to 32.206.223.25432.206.223.2558,190
12032.206.224.0/1932.206.224.1 to 32.206.255.25432.206.255.2558,190
12132.207.0.0/1932.207.0.1 to 32.207.31.25432.207.31.2558,190
12232.207.32.0/1932.207.32.1 to 32.207.63.25432.207.63.2558,190
12332.207.64.0/1932.207.64.1 to 32.207.95.25432.207.95.2558,190
12432.207.96.0/1932.207.96.1 to 32.207.127.25432.207.127.2558,190
12532.207.128.0/1932.207.128.1 to 32.207.159.25432.207.159.2558,190
12632.207.160.0/1932.207.160.1 to 32.207.191.25432.207.191.2558,190
12732.207.192.0/1932.207.192.1 to 32.207.223.25432.207.223.2558,190
12832.207.224.0/1932.207.224.1 to 32.207.255.25432.207.255.2558,190
12932.208.0.0/1932.208.0.1 to 32.208.31.25432.208.31.2558,190
13032.208.32.0/1932.208.32.1 to 32.208.63.25432.208.63.2558,190
13132.208.64.0/1932.208.64.1 to 32.208.95.25432.208.95.2558,190
13232.208.96.0/1932.208.96.1 to 32.208.127.25432.208.127.2558,190
13332.208.128.0/1932.208.128.1 to 32.208.159.25432.208.159.2558,190
13432.208.160.0/1932.208.160.1 to 32.208.191.25432.208.191.2558,190
13532.208.192.0/1932.208.192.1 to 32.208.223.25432.208.223.2558,190
13632.208.224.0/1932.208.224.1 to 32.208.255.25432.208.255.2558,190
13732.209.0.0/1932.209.0.1 to 32.209.31.25432.209.31.2558,190
13832.209.32.0/1932.209.32.1 to 32.209.63.25432.209.63.2558,190
13932.209.64.0/1932.209.64.1 to 32.209.95.25432.209.95.2558,190
14032.209.96.0/1932.209.96.1 to 32.209.127.25432.209.127.2558,190
14132.209.128.0/1932.209.128.1 to 32.209.159.25432.209.159.2558,190
14232.209.160.0/1932.209.160.1 to 32.209.191.25432.209.191.2558,190
14332.209.192.0/1932.209.192.1 to 32.209.223.25432.209.223.2558,190
14432.209.224.0/1932.209.224.1 to 32.209.255.25432.209.255.2558,190
14532.210.0.0/1932.210.0.1 to 32.210.31.25432.210.31.2558,190
14632.210.32.0/1932.210.32.1 to 32.210.63.25432.210.63.2558,190
14732.210.64.0/1932.210.64.1 to 32.210.95.25432.210.95.2558,190
14832.210.96.0/1932.210.96.1 to 32.210.127.25432.210.127.2558,190
14932.210.128.0/1932.210.128.1 to 32.210.159.25432.210.159.2558,190
15032.210.160.0/1932.210.160.1 to 32.210.191.25432.210.191.2558,190
15132.210.192.0/1932.210.192.1 to 32.210.223.25432.210.223.2558,190
15232.210.224.0/1932.210.224.1 to 32.210.255.25432.210.255.2558,190
15332.211.0.0/1932.211.0.1 to 32.211.31.25432.211.31.2558,190
15432.211.32.0/1932.211.32.1 to 32.211.63.25432.211.63.2558,190
15532.211.64.0/1932.211.64.1 to 32.211.95.25432.211.95.2558,190
15632.211.96.0/1932.211.96.1 to 32.211.127.25432.211.127.2558,190
15732.211.128.0/1932.211.128.1 to 32.211.159.25432.211.159.2558,190
15832.211.160.0/1932.211.160.1 to 32.211.191.25432.211.191.2558,190
15932.211.192.0/1932.211.192.1 to 32.211.223.25432.211.223.2558,190
16032.211.224.0/1932.211.224.1 to 32.211.255.25432.211.255.2558,190
16132.212.0.0/1932.212.0.1 to 32.212.31.25432.212.31.2558,190
16232.212.32.0/1932.212.32.1 to 32.212.63.25432.212.63.2558,190
16332.212.64.0/1932.212.64.1 to 32.212.95.25432.212.95.2558,190
16432.212.96.0/1932.212.96.1 to 32.212.127.25432.212.127.2558,190
16532.212.128.0/1932.212.128.1 to 32.212.159.25432.212.159.2558,190
16632.212.160.0/1932.212.160.1 to 32.212.191.25432.212.191.2558,190
16732.212.192.0/1932.212.192.1 to 32.212.223.25432.212.223.2558,190
16832.212.224.0/1932.212.224.1 to 32.212.255.25432.212.255.2558,190
16932.213.0.0/1932.213.0.1 to 32.213.31.25432.213.31.2558,190
17032.213.32.0/1932.213.32.1 to 32.213.63.25432.213.63.2558,190
17132.213.64.0/1932.213.64.1 to 32.213.95.25432.213.95.2558,190
17232.213.96.0/1932.213.96.1 to 32.213.127.25432.213.127.2558,190
17332.213.128.0/1932.213.128.1 to 32.213.159.25432.213.159.2558,190
17432.213.160.0/1932.213.160.1 to 32.213.191.25432.213.191.2558,190
17532.213.192.0/1932.213.192.1 to 32.213.223.25432.213.223.2558,190
17632.213.224.0/1932.213.224.1 to 32.213.255.25432.213.255.2558,190
17732.214.0.0/1932.214.0.1 to 32.214.31.25432.214.31.2558,190
17832.214.32.0/1932.214.32.1 to 32.214.63.25432.214.63.2558,190
17932.214.64.0/1932.214.64.1 to 32.214.95.25432.214.95.2558,190
18032.214.96.0/1932.214.96.1 to 32.214.127.25432.214.127.2558,190
18132.214.128.0/1932.214.128.1 to 32.214.159.25432.214.159.2558,190
18232.214.160.0/1932.214.160.1 to 32.214.191.25432.214.191.2558,190
18332.214.192.0/1932.214.192.1 to 32.214.223.25432.214.223.2558,190
18432.214.224.0/1932.214.224.1 to 32.214.255.25432.214.255.2558,190
18532.215.0.0/1932.215.0.1 to 32.215.31.25432.215.31.2558,190
18632.215.32.0/1932.215.32.1 to 32.215.63.25432.215.63.2558,190
18732.215.64.0/1932.215.64.1 to 32.215.95.25432.215.95.2558,190
18832.215.96.0/1932.215.96.1 to 32.215.127.25432.215.127.2558,190
18932.215.128.0/1932.215.128.1 to 32.215.159.25432.215.159.2558,190
19032.215.160.0/1932.215.160.1 to 32.215.191.25432.215.191.2558,190
19132.215.192.0/1932.215.192.1 to 32.215.223.25432.215.223.2558,190
19232.215.224.0/1932.215.224.1 to 32.215.255.25432.215.255.2558,190
19332.216.0.0/1932.216.0.1 to 32.216.31.25432.216.31.2558,190
19432.216.32.0/1932.216.32.1 to 32.216.63.25432.216.63.2558,190
19532.216.64.0/1932.216.64.1 to 32.216.95.25432.216.95.2558,190
19632.216.96.0/1932.216.96.1 to 32.216.127.25432.216.127.2558,190
19732.216.128.0/1932.216.128.1 to 32.216.159.25432.216.159.2558,190
19832.216.160.0/1932.216.160.1 to 32.216.191.25432.216.191.2558,190
19932.216.192.0/1932.216.192.1 to 32.216.223.25432.216.223.2558,190
20032.216.224.0/1932.216.224.1 to 32.216.255.25432.216.255.2558,190
20132.217.0.0/1932.217.0.1 to 32.217.31.25432.217.31.2558,190
20232.217.32.0/1932.217.32.1 to 32.217.63.25432.217.63.2558,190
20332.217.64.0/1932.217.64.1 to 32.217.95.25432.217.95.2558,190
20432.217.96.0/1932.217.96.1 to 32.217.127.25432.217.127.2558,190
20532.217.128.0/1932.217.128.1 to 32.217.159.25432.217.159.2558,190
20632.217.160.0/1932.217.160.1 to 32.217.191.25432.217.191.2558,190
20732.217.192.0/1932.217.192.1 to 32.217.223.25432.217.223.2558,190
20832.217.224.0/1932.217.224.1 to 32.217.255.25432.217.255.2558,190
20932.218.0.0/1932.218.0.1 to 32.218.31.25432.218.31.2558,190
21032.218.32.0/1932.218.32.1 to 32.218.63.25432.218.63.2558,190
21132.218.64.0/1932.218.64.1 to 32.218.95.25432.218.95.2558,190
21232.218.96.0/1932.218.96.1 to 32.218.127.25432.218.127.2558,190
21332.218.128.0/1932.218.128.1 to 32.218.159.25432.218.159.2558,190
21432.218.160.0/1932.218.160.1 to 32.218.191.25432.218.191.2558,190
21532.218.192.0/1932.218.192.1 to 32.218.223.25432.218.223.2558,190
21632.218.224.0/1932.218.224.1 to 32.218.255.25432.218.255.2558,190
21732.219.0.0/1932.219.0.1 to 32.219.31.25432.219.31.2558,190
21832.219.32.0/1932.219.32.1 to 32.219.63.25432.219.63.2558,190
21932.219.64.0/1932.219.64.1 to 32.219.95.25432.219.95.2558,190
22032.219.96.0/1932.219.96.1 to 32.219.127.25432.219.127.2558,190
22132.219.128.0/1932.219.128.1 to 32.219.159.25432.219.159.2558,190
22232.219.160.0/1932.219.160.1 to 32.219.191.25432.219.191.2558,190
22332.219.192.0/1932.219.192.1 to 32.219.223.25432.219.223.2558,190
22432.219.224.0/1932.219.224.1 to 32.219.255.25432.219.255.2558,190
22532.220.0.0/1932.220.0.1 to 32.220.31.25432.220.31.2558,190
22632.220.32.0/1932.220.32.1 to 32.220.63.25432.220.63.2558,190
22732.220.64.0/1932.220.64.1 to 32.220.95.25432.220.95.2558,190
22832.220.96.0/1932.220.96.1 to 32.220.127.25432.220.127.2558,190
22932.220.128.0/1932.220.128.1 to 32.220.159.25432.220.159.2558,190
23032.220.160.0/1932.220.160.1 to 32.220.191.25432.220.191.2558,190
23132.220.192.0/1932.220.192.1 to 32.220.223.25432.220.223.2558,190
23232.220.224.0/1932.220.224.1 to 32.220.255.25432.220.255.2558,190
23332.221.0.0/1932.221.0.1 to 32.221.31.25432.221.31.2558,190
23432.221.32.0/1932.221.32.1 to 32.221.63.25432.221.63.2558,190
23532.221.64.0/1932.221.64.1 to 32.221.95.25432.221.95.2558,190
23632.221.96.0/1932.221.96.1 to 32.221.127.25432.221.127.2558,190
23732.221.128.0/1932.221.128.1 to 32.221.159.25432.221.159.2558,190
23832.221.160.0/1932.221.160.1 to 32.221.191.25432.221.191.2558,190
23932.221.192.0/1932.221.192.1 to 32.221.223.25432.221.223.2558,190
24032.221.224.0/1932.221.224.1 to 32.221.255.25432.221.255.2558,190
24132.222.0.0/1932.222.0.1 to 32.222.31.25432.222.31.2558,190
24232.222.32.0/1932.222.32.1 to 32.222.63.25432.222.63.2558,190
24332.222.64.0/1932.222.64.1 to 32.222.95.25432.222.95.2558,190
24432.222.96.0/1932.222.96.1 to 32.222.127.25432.222.127.2558,190
24532.222.128.0/1932.222.128.1 to 32.222.159.25432.222.159.2558,190
24632.222.160.0/1932.222.160.1 to 32.222.191.25432.222.191.2558,190
24732.222.192.0/1932.222.192.1 to 32.222.223.25432.222.223.2558,190
24832.222.224.0/1932.222.224.1 to 32.222.255.25432.222.255.2558,190
24932.223.0.0/1932.223.0.1 to 32.223.31.25432.223.31.2558,190
25032.223.32.0/1932.223.32.1 to 32.223.63.25432.223.63.2558,190
25132.223.64.0/1932.223.64.1 to 32.223.95.25432.223.95.2558,190
25232.223.96.0/1932.223.96.1 to 32.223.127.25432.223.127.2558,190
25332.223.128.0/1932.223.128.1 to 32.223.159.25432.223.159.2558,190
25432.223.160.0/1932.223.160.1 to 32.223.191.25432.223.191.2558,190
25532.223.192.0/1932.223.192.1 to 32.223.223.25432.223.223.2558,190
25632.223.224.0/1932.223.224.1 to 32.223.255.25432.223.255.2558,190

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.