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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.

Network10.160.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
10.160.0.0
Broadcast address
10.191.255.255
First usable
10.160.0.1
Last usable
10.191.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Private (RFC 1918) 10.0.0.0/8
Office and home networks; not routed on the internet
Old class
A (default /8)
As numbers
Hex 0AA00000 · Integer 178257920 to 180355071
Reverse DNS zones
160.10.in-addr.arpa
161.10.in-addr.arpa
162.10.in-addr.arpa
163.10.in-addr.arpa
164.10.in-addr.arpa
165.10.in-addr.arpa
166.10.in-addr.arpa
167.10.in-addr.arpa
168.10.in-addr.arpa
169.10.in-addr.arpa
170.10.in-addr.arpa
171.10.in-addr.arpa
172.10.in-addr.arpa
173.10.in-addr.arpa
174.10.in-addr.arpa
175.10.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001010.10100000.00000000.0000000010.160.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network00001010.10100000.00000000.0000000010.160.0.0
Broadcast00001010.10111111.11111111.1111111110.191.255.255
Split into smaller subnets/19
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

10.160.0.0/11 makes 256 subnets of /19.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
110.160.0.0/1910.160.0.1 to 10.160.31.25410.160.31.2558,190
210.160.32.0/1910.160.32.1 to 10.160.63.25410.160.63.2558,190
310.160.64.0/1910.160.64.1 to 10.160.95.25410.160.95.2558,190
410.160.96.0/1910.160.96.1 to 10.160.127.25410.160.127.2558,190
510.160.128.0/1910.160.128.1 to 10.160.159.25410.160.159.2558,190
610.160.160.0/1910.160.160.1 to 10.160.191.25410.160.191.2558,190
710.160.192.0/1910.160.192.1 to 10.160.223.25410.160.223.2558,190
810.160.224.0/1910.160.224.1 to 10.160.255.25410.160.255.2558,190
910.161.0.0/1910.161.0.1 to 10.161.31.25410.161.31.2558,190
1010.161.32.0/1910.161.32.1 to 10.161.63.25410.161.63.2558,190
1110.161.64.0/1910.161.64.1 to 10.161.95.25410.161.95.2558,190
1210.161.96.0/1910.161.96.1 to 10.161.127.25410.161.127.2558,190
1310.161.128.0/1910.161.128.1 to 10.161.159.25410.161.159.2558,190
1410.161.160.0/1910.161.160.1 to 10.161.191.25410.161.191.2558,190
1510.161.192.0/1910.161.192.1 to 10.161.223.25410.161.223.2558,190
1610.161.224.0/1910.161.224.1 to 10.161.255.25410.161.255.2558,190
1710.162.0.0/1910.162.0.1 to 10.162.31.25410.162.31.2558,190
1810.162.32.0/1910.162.32.1 to 10.162.63.25410.162.63.2558,190
1910.162.64.0/1910.162.64.1 to 10.162.95.25410.162.95.2558,190
2010.162.96.0/1910.162.96.1 to 10.162.127.25410.162.127.2558,190
2110.162.128.0/1910.162.128.1 to 10.162.159.25410.162.159.2558,190
2210.162.160.0/1910.162.160.1 to 10.162.191.25410.162.191.2558,190
2310.162.192.0/1910.162.192.1 to 10.162.223.25410.162.223.2558,190
2410.162.224.0/1910.162.224.1 to 10.162.255.25410.162.255.2558,190
2510.163.0.0/1910.163.0.1 to 10.163.31.25410.163.31.2558,190
2610.163.32.0/1910.163.32.1 to 10.163.63.25410.163.63.2558,190
2710.163.64.0/1910.163.64.1 to 10.163.95.25410.163.95.2558,190
2810.163.96.0/1910.163.96.1 to 10.163.127.25410.163.127.2558,190
2910.163.128.0/1910.163.128.1 to 10.163.159.25410.163.159.2558,190
3010.163.160.0/1910.163.160.1 to 10.163.191.25410.163.191.2558,190
3110.163.192.0/1910.163.192.1 to 10.163.223.25410.163.223.2558,190
3210.163.224.0/1910.163.224.1 to 10.163.255.25410.163.255.2558,190
3310.164.0.0/1910.164.0.1 to 10.164.31.25410.164.31.2558,190
3410.164.32.0/1910.164.32.1 to 10.164.63.25410.164.63.2558,190
3510.164.64.0/1910.164.64.1 to 10.164.95.25410.164.95.2558,190
3610.164.96.0/1910.164.96.1 to 10.164.127.25410.164.127.2558,190
3710.164.128.0/1910.164.128.1 to 10.164.159.25410.164.159.2558,190
3810.164.160.0/1910.164.160.1 to 10.164.191.25410.164.191.2558,190
3910.164.192.0/1910.164.192.1 to 10.164.223.25410.164.223.2558,190
4010.164.224.0/1910.164.224.1 to 10.164.255.25410.164.255.2558,190
4110.165.0.0/1910.165.0.1 to 10.165.31.25410.165.31.2558,190
4210.165.32.0/1910.165.32.1 to 10.165.63.25410.165.63.2558,190
4310.165.64.0/1910.165.64.1 to 10.165.95.25410.165.95.2558,190
4410.165.96.0/1910.165.96.1 to 10.165.127.25410.165.127.2558,190
4510.165.128.0/1910.165.128.1 to 10.165.159.25410.165.159.2558,190
4610.165.160.0/1910.165.160.1 to 10.165.191.25410.165.191.2558,190
4710.165.192.0/1910.165.192.1 to 10.165.223.25410.165.223.2558,190
4810.165.224.0/1910.165.224.1 to 10.165.255.25410.165.255.2558,190
4910.166.0.0/1910.166.0.1 to 10.166.31.25410.166.31.2558,190
5010.166.32.0/1910.166.32.1 to 10.166.63.25410.166.63.2558,190
5110.166.64.0/1910.166.64.1 to 10.166.95.25410.166.95.2558,190
5210.166.96.0/1910.166.96.1 to 10.166.127.25410.166.127.2558,190
5310.166.128.0/1910.166.128.1 to 10.166.159.25410.166.159.2558,190
5410.166.160.0/1910.166.160.1 to 10.166.191.25410.166.191.2558,190
5510.166.192.0/1910.166.192.1 to 10.166.223.25410.166.223.2558,190
5610.166.224.0/1910.166.224.1 to 10.166.255.25410.166.255.2558,190
5710.167.0.0/1910.167.0.1 to 10.167.31.25410.167.31.2558,190
5810.167.32.0/1910.167.32.1 to 10.167.63.25410.167.63.2558,190
5910.167.64.0/1910.167.64.1 to 10.167.95.25410.167.95.2558,190
6010.167.96.0/1910.167.96.1 to 10.167.127.25410.167.127.2558,190
6110.167.128.0/1910.167.128.1 to 10.167.159.25410.167.159.2558,190
6210.167.160.0/1910.167.160.1 to 10.167.191.25410.167.191.2558,190
6310.167.192.0/1910.167.192.1 to 10.167.223.25410.167.223.2558,190
6410.167.224.0/1910.167.224.1 to 10.167.255.25410.167.255.2558,190
6510.168.0.0/1910.168.0.1 to 10.168.31.25410.168.31.2558,190
6610.168.32.0/1910.168.32.1 to 10.168.63.25410.168.63.2558,190
6710.168.64.0/1910.168.64.1 to 10.168.95.25410.168.95.2558,190
6810.168.96.0/1910.168.96.1 to 10.168.127.25410.168.127.2558,190
6910.168.128.0/1910.168.128.1 to 10.168.159.25410.168.159.2558,190
7010.168.160.0/1910.168.160.1 to 10.168.191.25410.168.191.2558,190
7110.168.192.0/1910.168.192.1 to 10.168.223.25410.168.223.2558,190
7210.168.224.0/1910.168.224.1 to 10.168.255.25410.168.255.2558,190
7310.169.0.0/1910.169.0.1 to 10.169.31.25410.169.31.2558,190
7410.169.32.0/1910.169.32.1 to 10.169.63.25410.169.63.2558,190
7510.169.64.0/1910.169.64.1 to 10.169.95.25410.169.95.2558,190
7610.169.96.0/1910.169.96.1 to 10.169.127.25410.169.127.2558,190
7710.169.128.0/1910.169.128.1 to 10.169.159.25410.169.159.2558,190
7810.169.160.0/1910.169.160.1 to 10.169.191.25410.169.191.2558,190
7910.169.192.0/1910.169.192.1 to 10.169.223.25410.169.223.2558,190
8010.169.224.0/1910.169.224.1 to 10.169.255.25410.169.255.2558,190
8110.170.0.0/1910.170.0.1 to 10.170.31.25410.170.31.2558,190
8210.170.32.0/1910.170.32.1 to 10.170.63.25410.170.63.2558,190
8310.170.64.0/1910.170.64.1 to 10.170.95.25410.170.95.2558,190
8410.170.96.0/1910.170.96.1 to 10.170.127.25410.170.127.2558,190
8510.170.128.0/1910.170.128.1 to 10.170.159.25410.170.159.2558,190
8610.170.160.0/1910.170.160.1 to 10.170.191.25410.170.191.2558,190
8710.170.192.0/1910.170.192.1 to 10.170.223.25410.170.223.2558,190
8810.170.224.0/1910.170.224.1 to 10.170.255.25410.170.255.2558,190
8910.171.0.0/1910.171.0.1 to 10.171.31.25410.171.31.2558,190
9010.171.32.0/1910.171.32.1 to 10.171.63.25410.171.63.2558,190
9110.171.64.0/1910.171.64.1 to 10.171.95.25410.171.95.2558,190
9210.171.96.0/1910.171.96.1 to 10.171.127.25410.171.127.2558,190
9310.171.128.0/1910.171.128.1 to 10.171.159.25410.171.159.2558,190
9410.171.160.0/1910.171.160.1 to 10.171.191.25410.171.191.2558,190
9510.171.192.0/1910.171.192.1 to 10.171.223.25410.171.223.2558,190
9610.171.224.0/1910.171.224.1 to 10.171.255.25410.171.255.2558,190
9710.172.0.0/1910.172.0.1 to 10.172.31.25410.172.31.2558,190
9810.172.32.0/1910.172.32.1 to 10.172.63.25410.172.63.2558,190
9910.172.64.0/1910.172.64.1 to 10.172.95.25410.172.95.2558,190
10010.172.96.0/1910.172.96.1 to 10.172.127.25410.172.127.2558,190
10110.172.128.0/1910.172.128.1 to 10.172.159.25410.172.159.2558,190
10210.172.160.0/1910.172.160.1 to 10.172.191.25410.172.191.2558,190
10310.172.192.0/1910.172.192.1 to 10.172.223.25410.172.223.2558,190
10410.172.224.0/1910.172.224.1 to 10.172.255.25410.172.255.2558,190
10510.173.0.0/1910.173.0.1 to 10.173.31.25410.173.31.2558,190
10610.173.32.0/1910.173.32.1 to 10.173.63.25410.173.63.2558,190
10710.173.64.0/1910.173.64.1 to 10.173.95.25410.173.95.2558,190
10810.173.96.0/1910.173.96.1 to 10.173.127.25410.173.127.2558,190
10910.173.128.0/1910.173.128.1 to 10.173.159.25410.173.159.2558,190
11010.173.160.0/1910.173.160.1 to 10.173.191.25410.173.191.2558,190
11110.173.192.0/1910.173.192.1 to 10.173.223.25410.173.223.2558,190
11210.173.224.0/1910.173.224.1 to 10.173.255.25410.173.255.2558,190
11310.174.0.0/1910.174.0.1 to 10.174.31.25410.174.31.2558,190
11410.174.32.0/1910.174.32.1 to 10.174.63.25410.174.63.2558,190
11510.174.64.0/1910.174.64.1 to 10.174.95.25410.174.95.2558,190
11610.174.96.0/1910.174.96.1 to 10.174.127.25410.174.127.2558,190
11710.174.128.0/1910.174.128.1 to 10.174.159.25410.174.159.2558,190
11810.174.160.0/1910.174.160.1 to 10.174.191.25410.174.191.2558,190
11910.174.192.0/1910.174.192.1 to 10.174.223.25410.174.223.2558,190
12010.174.224.0/1910.174.224.1 to 10.174.255.25410.174.255.2558,190
12110.175.0.0/1910.175.0.1 to 10.175.31.25410.175.31.2558,190
12210.175.32.0/1910.175.32.1 to 10.175.63.25410.175.63.2558,190
12310.175.64.0/1910.175.64.1 to 10.175.95.25410.175.95.2558,190
12410.175.96.0/1910.175.96.1 to 10.175.127.25410.175.127.2558,190
12510.175.128.0/1910.175.128.1 to 10.175.159.25410.175.159.2558,190
12610.175.160.0/1910.175.160.1 to 10.175.191.25410.175.191.2558,190
12710.175.192.0/1910.175.192.1 to 10.175.223.25410.175.223.2558,190
12810.175.224.0/1910.175.224.1 to 10.175.255.25410.175.255.2558,190
12910.176.0.0/1910.176.0.1 to 10.176.31.25410.176.31.2558,190
13010.176.32.0/1910.176.32.1 to 10.176.63.25410.176.63.2558,190
13110.176.64.0/1910.176.64.1 to 10.176.95.25410.176.95.2558,190
13210.176.96.0/1910.176.96.1 to 10.176.127.25410.176.127.2558,190
13310.176.128.0/1910.176.128.1 to 10.176.159.25410.176.159.2558,190
13410.176.160.0/1910.176.160.1 to 10.176.191.25410.176.191.2558,190
13510.176.192.0/1910.176.192.1 to 10.176.223.25410.176.223.2558,190
13610.176.224.0/1910.176.224.1 to 10.176.255.25410.176.255.2558,190
13710.177.0.0/1910.177.0.1 to 10.177.31.25410.177.31.2558,190
13810.177.32.0/1910.177.32.1 to 10.177.63.25410.177.63.2558,190
13910.177.64.0/1910.177.64.1 to 10.177.95.25410.177.95.2558,190
14010.177.96.0/1910.177.96.1 to 10.177.127.25410.177.127.2558,190
14110.177.128.0/1910.177.128.1 to 10.177.159.25410.177.159.2558,190
14210.177.160.0/1910.177.160.1 to 10.177.191.25410.177.191.2558,190
14310.177.192.0/1910.177.192.1 to 10.177.223.25410.177.223.2558,190
14410.177.224.0/1910.177.224.1 to 10.177.255.25410.177.255.2558,190
14510.178.0.0/1910.178.0.1 to 10.178.31.25410.178.31.2558,190
14610.178.32.0/1910.178.32.1 to 10.178.63.25410.178.63.2558,190
14710.178.64.0/1910.178.64.1 to 10.178.95.25410.178.95.2558,190
14810.178.96.0/1910.178.96.1 to 10.178.127.25410.178.127.2558,190
14910.178.128.0/1910.178.128.1 to 10.178.159.25410.178.159.2558,190
15010.178.160.0/1910.178.160.1 to 10.178.191.25410.178.191.2558,190
15110.178.192.0/1910.178.192.1 to 10.178.223.25410.178.223.2558,190
15210.178.224.0/1910.178.224.1 to 10.178.255.25410.178.255.2558,190
15310.179.0.0/1910.179.0.1 to 10.179.31.25410.179.31.2558,190
15410.179.32.0/1910.179.32.1 to 10.179.63.25410.179.63.2558,190
15510.179.64.0/1910.179.64.1 to 10.179.95.25410.179.95.2558,190
15610.179.96.0/1910.179.96.1 to 10.179.127.25410.179.127.2558,190
15710.179.128.0/1910.179.128.1 to 10.179.159.25410.179.159.2558,190
15810.179.160.0/1910.179.160.1 to 10.179.191.25410.179.191.2558,190
15910.179.192.0/1910.179.192.1 to 10.179.223.25410.179.223.2558,190
16010.179.224.0/1910.179.224.1 to 10.179.255.25410.179.255.2558,190
16110.180.0.0/1910.180.0.1 to 10.180.31.25410.180.31.2558,190
16210.180.32.0/1910.180.32.1 to 10.180.63.25410.180.63.2558,190
16310.180.64.0/1910.180.64.1 to 10.180.95.25410.180.95.2558,190
16410.180.96.0/1910.180.96.1 to 10.180.127.25410.180.127.2558,190
16510.180.128.0/1910.180.128.1 to 10.180.159.25410.180.159.2558,190
16610.180.160.0/1910.180.160.1 to 10.180.191.25410.180.191.2558,190
16710.180.192.0/1910.180.192.1 to 10.180.223.25410.180.223.2558,190
16810.180.224.0/1910.180.224.1 to 10.180.255.25410.180.255.2558,190
16910.181.0.0/1910.181.0.1 to 10.181.31.25410.181.31.2558,190
17010.181.32.0/1910.181.32.1 to 10.181.63.25410.181.63.2558,190
17110.181.64.0/1910.181.64.1 to 10.181.95.25410.181.95.2558,190
17210.181.96.0/1910.181.96.1 to 10.181.127.25410.181.127.2558,190
17310.181.128.0/1910.181.128.1 to 10.181.159.25410.181.159.2558,190
17410.181.160.0/1910.181.160.1 to 10.181.191.25410.181.191.2558,190
17510.181.192.0/1910.181.192.1 to 10.181.223.25410.181.223.2558,190
17610.181.224.0/1910.181.224.1 to 10.181.255.25410.181.255.2558,190
17710.182.0.0/1910.182.0.1 to 10.182.31.25410.182.31.2558,190
17810.182.32.0/1910.182.32.1 to 10.182.63.25410.182.63.2558,190
17910.182.64.0/1910.182.64.1 to 10.182.95.25410.182.95.2558,190
18010.182.96.0/1910.182.96.1 to 10.182.127.25410.182.127.2558,190
18110.182.128.0/1910.182.128.1 to 10.182.159.25410.182.159.2558,190
18210.182.160.0/1910.182.160.1 to 10.182.191.25410.182.191.2558,190
18310.182.192.0/1910.182.192.1 to 10.182.223.25410.182.223.2558,190
18410.182.224.0/1910.182.224.1 to 10.182.255.25410.182.255.2558,190
18510.183.0.0/1910.183.0.1 to 10.183.31.25410.183.31.2558,190
18610.183.32.0/1910.183.32.1 to 10.183.63.25410.183.63.2558,190
18710.183.64.0/1910.183.64.1 to 10.183.95.25410.183.95.2558,190
18810.183.96.0/1910.183.96.1 to 10.183.127.25410.183.127.2558,190
18910.183.128.0/1910.183.128.1 to 10.183.159.25410.183.159.2558,190
19010.183.160.0/1910.183.160.1 to 10.183.191.25410.183.191.2558,190
19110.183.192.0/1910.183.192.1 to 10.183.223.25410.183.223.2558,190
19210.183.224.0/1910.183.224.1 to 10.183.255.25410.183.255.2558,190
19310.184.0.0/1910.184.0.1 to 10.184.31.25410.184.31.2558,190
19410.184.32.0/1910.184.32.1 to 10.184.63.25410.184.63.2558,190
19510.184.64.0/1910.184.64.1 to 10.184.95.25410.184.95.2558,190
19610.184.96.0/1910.184.96.1 to 10.184.127.25410.184.127.2558,190
19710.184.128.0/1910.184.128.1 to 10.184.159.25410.184.159.2558,190
19810.184.160.0/1910.184.160.1 to 10.184.191.25410.184.191.2558,190
19910.184.192.0/1910.184.192.1 to 10.184.223.25410.184.223.2558,190
20010.184.224.0/1910.184.224.1 to 10.184.255.25410.184.255.2558,190
20110.185.0.0/1910.185.0.1 to 10.185.31.25410.185.31.2558,190
20210.185.32.0/1910.185.32.1 to 10.185.63.25410.185.63.2558,190
20310.185.64.0/1910.185.64.1 to 10.185.95.25410.185.95.2558,190
20410.185.96.0/1910.185.96.1 to 10.185.127.25410.185.127.2558,190
20510.185.128.0/1910.185.128.1 to 10.185.159.25410.185.159.2558,190
20610.185.160.0/1910.185.160.1 to 10.185.191.25410.185.191.2558,190
20710.185.192.0/1910.185.192.1 to 10.185.223.25410.185.223.2558,190
20810.185.224.0/1910.185.224.1 to 10.185.255.25410.185.255.2558,190
20910.186.0.0/1910.186.0.1 to 10.186.31.25410.186.31.2558,190
21010.186.32.0/1910.186.32.1 to 10.186.63.25410.186.63.2558,190
21110.186.64.0/1910.186.64.1 to 10.186.95.25410.186.95.2558,190
21210.186.96.0/1910.186.96.1 to 10.186.127.25410.186.127.2558,190
21310.186.128.0/1910.186.128.1 to 10.186.159.25410.186.159.2558,190
21410.186.160.0/1910.186.160.1 to 10.186.191.25410.186.191.2558,190
21510.186.192.0/1910.186.192.1 to 10.186.223.25410.186.223.2558,190
21610.186.224.0/1910.186.224.1 to 10.186.255.25410.186.255.2558,190
21710.187.0.0/1910.187.0.1 to 10.187.31.25410.187.31.2558,190
21810.187.32.0/1910.187.32.1 to 10.187.63.25410.187.63.2558,190
21910.187.64.0/1910.187.64.1 to 10.187.95.25410.187.95.2558,190
22010.187.96.0/1910.187.96.1 to 10.187.127.25410.187.127.2558,190
22110.187.128.0/1910.187.128.1 to 10.187.159.25410.187.159.2558,190
22210.187.160.0/1910.187.160.1 to 10.187.191.25410.187.191.2558,190
22310.187.192.0/1910.187.192.1 to 10.187.223.25410.187.223.2558,190
22410.187.224.0/1910.187.224.1 to 10.187.255.25410.187.255.2558,190
22510.188.0.0/1910.188.0.1 to 10.188.31.25410.188.31.2558,190
22610.188.32.0/1910.188.32.1 to 10.188.63.25410.188.63.2558,190
22710.188.64.0/1910.188.64.1 to 10.188.95.25410.188.95.2558,190
22810.188.96.0/1910.188.96.1 to 10.188.127.25410.188.127.2558,190
22910.188.128.0/1910.188.128.1 to 10.188.159.25410.188.159.2558,190
23010.188.160.0/1910.188.160.1 to 10.188.191.25410.188.191.2558,190
23110.188.192.0/1910.188.192.1 to 10.188.223.25410.188.223.2558,190
23210.188.224.0/1910.188.224.1 to 10.188.255.25410.188.255.2558,190
23310.189.0.0/1910.189.0.1 to 10.189.31.25410.189.31.2558,190
23410.189.32.0/1910.189.32.1 to 10.189.63.25410.189.63.2558,190
23510.189.64.0/1910.189.64.1 to 10.189.95.25410.189.95.2558,190
23610.189.96.0/1910.189.96.1 to 10.189.127.25410.189.127.2558,190
23710.189.128.0/1910.189.128.1 to 10.189.159.25410.189.159.2558,190
23810.189.160.0/1910.189.160.1 to 10.189.191.25410.189.191.2558,190
23910.189.192.0/1910.189.192.1 to 10.189.223.25410.189.223.2558,190
24010.189.224.0/1910.189.224.1 to 10.189.255.25410.189.255.2558,190
24110.190.0.0/1910.190.0.1 to 10.190.31.25410.190.31.2558,190
24210.190.32.0/1910.190.32.1 to 10.190.63.25410.190.63.2558,190
24310.190.64.0/1910.190.64.1 to 10.190.95.25410.190.95.2558,190
24410.190.96.0/1910.190.96.1 to 10.190.127.25410.190.127.2558,190
24510.190.128.0/1910.190.128.1 to 10.190.159.25410.190.159.2558,190
24610.190.160.0/1910.190.160.1 to 10.190.191.25410.190.191.2558,190
24710.190.192.0/1910.190.192.1 to 10.190.223.25410.190.223.2558,190
24810.190.224.0/1910.190.224.1 to 10.190.255.25410.190.255.2558,190
24910.191.0.0/1910.191.0.1 to 10.191.31.25410.191.31.2558,190
25010.191.32.0/1910.191.32.1 to 10.191.63.25410.191.63.2558,190
25110.191.64.0/1910.191.64.1 to 10.191.95.25410.191.95.2558,190
25210.191.96.0/1910.191.96.1 to 10.191.127.25410.191.127.2558,190
25310.191.128.0/1910.191.128.1 to 10.191.159.25410.191.159.2558,190
25410.191.160.0/1910.191.160.1 to 10.191.191.25410.191.191.2558,190
25510.191.192.0/1910.191.192.1 to 10.191.223.25410.191.223.2558,190
25610.191.224.0/1910.191.224.1 to 10.191.255.25410.191.255.2558,190

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.