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IPv4 Subnet Calculator

Enter an IP with a CIDR prefix or a subnet mask to see its network, broadcast, host range, and host count. You can also split the network into smaller subnets.

$ ipcalc
Try:192.168.1.10/2410.0.0.0/8172.16.5.4/20203.0.113.9/29
IPv6 calculator →
private IP (RFC 1918)10.2.128.0/18
network10.2.128.0/18
broadcast10.2.191.255
first host10.2.128.1
last host10.2.191.254
subnet mask255.255.192.0
wildcard0.0.63.255
addresses16,384
usable hosts16,382
classA
ipcalc 10.2.128.0/18
address00001010.00000010.10000000.00000000
subnet mask11111111.11111111.11000000.00000000
network00001010.00000010.10000000.00000000
broadcast00001010.00000010.10111111.11111111
green = network part, grey = host part
hex0x0a028000
decimal167936000
reverse dns0.128.2.10.in-addr.arpa
ipv4-mapped::ffff:a02:8000

/18 split into /23 · 32 subnets

close ×
#networkhost rangebroadcast
110.2.128.0/2310.2.128.1 – 10.2.129.25410.2.129.255
210.2.130.0/2310.2.130.1 – 10.2.131.25410.2.131.255
310.2.132.0/2310.2.132.1 – 10.2.133.25410.2.133.255
410.2.134.0/2310.2.134.1 – 10.2.135.25410.2.135.255
510.2.136.0/2310.2.136.1 – 10.2.137.25410.2.137.255
610.2.138.0/2310.2.138.1 – 10.2.139.25410.2.139.255
710.2.140.0/2310.2.140.1 – 10.2.141.25410.2.141.255
810.2.142.0/2310.2.142.1 – 10.2.143.25410.2.143.255
910.2.144.0/2310.2.144.1 – 10.2.145.25410.2.145.255
1010.2.146.0/2310.2.146.1 – 10.2.147.25410.2.147.255
1110.2.148.0/2310.2.148.1 – 10.2.149.25410.2.149.255
1210.2.150.0/2310.2.150.1 – 10.2.151.25410.2.151.255
1310.2.152.0/2310.2.152.1 – 10.2.153.25410.2.153.255
1410.2.154.0/2310.2.154.1 – 10.2.155.25410.2.155.255
1510.2.156.0/2310.2.156.1 – 10.2.157.25410.2.157.255
1610.2.158.0/2310.2.158.1 – 10.2.159.25410.2.159.255
1710.2.160.0/2310.2.160.1 – 10.2.161.25410.2.161.255
1810.2.162.0/2310.2.162.1 – 10.2.163.25410.2.163.255
1910.2.164.0/2310.2.164.1 – 10.2.165.25410.2.165.255
2010.2.166.0/2310.2.166.1 – 10.2.167.25410.2.167.255
2110.2.168.0/2310.2.168.1 – 10.2.169.25410.2.169.255
2210.2.170.0/2310.2.170.1 – 10.2.171.25410.2.171.255
2310.2.172.0/2310.2.172.1 – 10.2.173.25410.2.173.255
2410.2.174.0/2310.2.174.1 – 10.2.175.25410.2.175.255
2510.2.176.0/2310.2.176.1 – 10.2.177.25410.2.177.255
2610.2.178.0/2310.2.178.1 – 10.2.179.25410.2.179.255
2710.2.180.0/2310.2.180.1 – 10.2.181.25410.2.181.255
2810.2.182.0/2310.2.182.1 – 10.2.183.25410.2.183.255
2910.2.184.0/2310.2.184.1 – 10.2.185.25410.2.185.255
3010.2.186.0/2310.2.186.1 – 10.2.187.25410.2.187.255
3110.2.188.0/2310.2.188.1 – 10.2.189.25410.2.189.255
3210.2.190.0/2310.2.190.1 – 10.2.191.25410.2.191.255
01 / table

IPv4 CIDR prefix table.

Click a prefix longer than your network to split it into subnets.

prefixsubnet maskaddresseshostsin your /18
/00.0.0.04,294,967,2964,294,967,294-
/1128.0.0.02,147,483,6482,147,483,646-
/2192.0.0.01,073,741,8241,073,741,822-
/3224.0.0.0536,870,912536,870,910-
/4240.0.0.0268,435,456268,435,454-
/5248.0.0.0134,217,728134,217,726-
/6252.0.0.067,108,86467,108,862-
/7254.0.0.033,554,43233,554,430-
/8255.0.0.016,777,21616,777,214-
/9255.128.0.08,388,6088,388,606-
/10255.192.0.04,194,3044,194,302-
/11255.224.0.02,097,1522,097,150-
/12255.240.0.01,048,5761,048,574-
/13255.248.0.0524,288524,286-
/14255.252.0.0262,144262,142-
/15255.254.0.0131,072131,070-
/16255.255.0.065,53665,534-
/17255.255.128.032,76832,766-
/18255.255.192.016,38416,3821
/19255.255.224.08,1928,1902 split →
/20255.255.240.04,0964,0944 split →
/21255.255.248.02,0482,0468 split →
/22255.255.252.01,0241,02216 split →
/23255.255.254.051251032 split →
/24255.255.255.025625464 split →
/25255.255.255.128128126128 split →
/26255.255.255.1926462256 split →
/27255.255.255.2243230512 split →
/28255.255.255.24016141,024 split →
/29255.255.255.248862,048 split →
/30255.255.255.252424,096 split →
/31255.255.255.254228,192 split →
/32255.255.255.2551116,384 split →
02 / faq

About this calculator.

How do I use this subnet calculator?

▼

Type an IP address followed by a prefix, like 192.168.1.10/24, or by a subnet mask, like 192.168.1.10 255.255.255.0. Without a prefix it uses /24. Click a row in the table to split the network into smaller subnets.

Why are usable hosts always 2 fewer?

▼

The first address in a subnet is the network address and the last is the broadcast address, so neither can go to a device. The exceptions are /31 (point-to-point links, RFC 3021) and /32 (a single address), which use every address.

Can I use it from a terminal?

▼

Yes. curl 'ipku.in/en/tools/ipv4-subnet-calculator?q=192.168.1.10/24' returns the result as plain text.

Learn how to work it out →