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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)10.37.64.0/18
network10.37.64.0/18
broadcast10.37.127.255
first host10.37.64.1
last host10.37.127.254
subnet mask255.255.192.0
wildcard0.0.63.255
addresses16,384
usable hosts16,382
classA
ipcalc 10.37.64.0/18
address00001010.00100101.01000000.00000000
subnet mask11111111.11111111.11000000.00000000
network00001010.00100101.01000000.00000000
broadcast00001010.00100101.01111111.11111111
green = network part, grey = host part
hex0x0a254000
decimal170213376
reverse dns0.64.37.10.in-addr.arpa
ipv4-mapped::ffff:a25:4000

/18 split into /23 · 32 subnets

close ×
#networkhost rangebroadcast
110.37.64.0/2310.37.64.1 – 10.37.65.25410.37.65.255
210.37.66.0/2310.37.66.1 – 10.37.67.25410.37.67.255
310.37.68.0/2310.37.68.1 – 10.37.69.25410.37.69.255
410.37.70.0/2310.37.70.1 – 10.37.71.25410.37.71.255
510.37.72.0/2310.37.72.1 – 10.37.73.25410.37.73.255
610.37.74.0/2310.37.74.1 – 10.37.75.25410.37.75.255
710.37.76.0/2310.37.76.1 – 10.37.77.25410.37.77.255
810.37.78.0/2310.37.78.1 – 10.37.79.25410.37.79.255
910.37.80.0/2310.37.80.1 – 10.37.81.25410.37.81.255
1010.37.82.0/2310.37.82.1 – 10.37.83.25410.37.83.255
1110.37.84.0/2310.37.84.1 – 10.37.85.25410.37.85.255
1210.37.86.0/2310.37.86.1 – 10.37.87.25410.37.87.255
1310.37.88.0/2310.37.88.1 – 10.37.89.25410.37.89.255
1410.37.90.0/2310.37.90.1 – 10.37.91.25410.37.91.255
1510.37.92.0/2310.37.92.1 – 10.37.93.25410.37.93.255
1610.37.94.0/2310.37.94.1 – 10.37.95.25410.37.95.255
1710.37.96.0/2310.37.96.1 – 10.37.97.25410.37.97.255
1810.37.98.0/2310.37.98.1 – 10.37.99.25410.37.99.255
1910.37.100.0/2310.37.100.1 – 10.37.101.25410.37.101.255
2010.37.102.0/2310.37.102.1 – 10.37.103.25410.37.103.255
2110.37.104.0/2310.37.104.1 – 10.37.105.25410.37.105.255
2210.37.106.0/2310.37.106.1 – 10.37.107.25410.37.107.255
2310.37.108.0/2310.37.108.1 – 10.37.109.25410.37.109.255
2410.37.110.0/2310.37.110.1 – 10.37.111.25410.37.111.255
2510.37.112.0/2310.37.112.1 – 10.37.113.25410.37.113.255
2610.37.114.0/2310.37.114.1 – 10.37.115.25410.37.115.255
2710.37.116.0/2310.37.116.1 – 10.37.117.25410.37.117.255
2810.37.118.0/2310.37.118.1 – 10.37.119.25410.37.119.255
2910.37.120.0/2310.37.120.1 – 10.37.121.25410.37.121.255
3010.37.122.0/2310.37.122.1 – 10.37.123.25410.37.123.255
3110.37.124.0/2310.37.124.1 – 10.37.125.25410.37.125.255
3210.37.126.0/2310.37.126.1 – 10.37.127.25410.37.127.255
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 →