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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)10.64.0.0/16
network10.64.0.0/16
broadcast10.64.255.255
first host10.64.0.1
last host10.64.255.254
subnet mask255.255.0.0
wildcard0.0.255.255
addresses65,536
usable hosts65,534
classA
ipcalc 10.64.0.0/16
address00001010.01000000.00000000.00000000
subnet mask11111111.11111111.00000000.00000000
network00001010.01000000.00000000.00000000
broadcast00001010.01000000.11111111.11111111
green = network part, grey = host part
hex0x0a400000
decimal171966464
reverse dns0.0.64.10.in-addr.arpa
ipv4-mapped::ffff:a40:0

/16 split into /21 · 32 subnets

close ×
#networkhost rangebroadcast
110.64.0.0/2110.64.0.1 – 10.64.7.25410.64.7.255
210.64.8.0/2110.64.8.1 – 10.64.15.25410.64.15.255
310.64.16.0/2110.64.16.1 – 10.64.23.25410.64.23.255
410.64.24.0/2110.64.24.1 – 10.64.31.25410.64.31.255
510.64.32.0/2110.64.32.1 – 10.64.39.25410.64.39.255
610.64.40.0/2110.64.40.1 – 10.64.47.25410.64.47.255
710.64.48.0/2110.64.48.1 – 10.64.55.25410.64.55.255
810.64.56.0/2110.64.56.1 – 10.64.63.25410.64.63.255
910.64.64.0/2110.64.64.1 – 10.64.71.25410.64.71.255
1010.64.72.0/2110.64.72.1 – 10.64.79.25410.64.79.255
1110.64.80.0/2110.64.80.1 – 10.64.87.25410.64.87.255
1210.64.88.0/2110.64.88.1 – 10.64.95.25410.64.95.255
1310.64.96.0/2110.64.96.1 – 10.64.103.25410.64.103.255
1410.64.104.0/2110.64.104.1 – 10.64.111.25410.64.111.255
1510.64.112.0/2110.64.112.1 – 10.64.119.25410.64.119.255
1610.64.120.0/2110.64.120.1 – 10.64.127.25410.64.127.255
1710.64.128.0/2110.64.128.1 – 10.64.135.25410.64.135.255
1810.64.136.0/2110.64.136.1 – 10.64.143.25410.64.143.255
1910.64.144.0/2110.64.144.1 – 10.64.151.25410.64.151.255
2010.64.152.0/2110.64.152.1 – 10.64.159.25410.64.159.255
2110.64.160.0/2110.64.160.1 – 10.64.167.25410.64.167.255
2210.64.168.0/2110.64.168.1 – 10.64.175.25410.64.175.255
2310.64.176.0/2110.64.176.1 – 10.64.183.25410.64.183.255
2410.64.184.0/2110.64.184.1 – 10.64.191.25410.64.191.255
2510.64.192.0/2110.64.192.1 – 10.64.199.25410.64.199.255
2610.64.200.0/2110.64.200.1 – 10.64.207.25410.64.207.255
2710.64.208.0/2110.64.208.1 – 10.64.215.25410.64.215.255
2810.64.216.0/2110.64.216.1 – 10.64.223.25410.64.223.255
2910.64.224.0/2110.64.224.1 – 10.64.231.25410.64.231.255
3010.64.232.0/2110.64.232.1 – 10.64.239.25410.64.239.255
3110.64.240.0/2110.64.240.1 – 10.64.247.25410.64.247.255
3210.64.248.0/2110.64.248.1 – 10.64.255.25410.64.255.255
01 / table

IPv4 CIDR prefix table.

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

prefixsubnet maskaddresseshostsin your /16
/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-
/16255.255.0.065,53665,5341
/17255.255.128.032,76832,7662 split →
/18255.255.192.016,38416,3824 split →
/19255.255.224.08,1928,1908 split →
/20255.255.240.04,0964,09416 split →
/21255.255.248.02,0482,04632 split →
/22255.255.252.01,0241,02264 split →
/23255.255.254.0512510128 split →
/24255.255.255.0256254256 split →
/25255.255.255.128128126512 split →
/26255.255.255.19264621,024 split →
/27255.255.255.22432302,048 split →
/28255.255.255.24016144,096 split →
/29255.255.255.248868,192 split →
/30255.255.255.2524216,384 split →
/31255.255.255.2542232,768 split →
/32255.255.255.2551165,536 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 →