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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)10.31.128.0/19
network10.31.128.0/19
broadcast10.31.159.255
first host10.31.128.1
last host10.31.159.254
subnet mask255.255.224.0
wildcard0.0.31.255
addresses8,192
usable hosts8,190
classA
ipcalc 10.31.128.0/19
address00001010.00011111.10000000.00000000
subnet mask11111111.11111111.11100000.00000000
network00001010.00011111.10000000.00000000
broadcast00001010.00011111.10011111.11111111
green = network part, grey = host part
hex0x0a1f8000
decimal169836544
reverse dns0.128.31.10.in-addr.arpa
ipv4-mapped::ffff:a1f:8000

/19 split into /25 · 64 subnets

close ×
#networkhost rangebroadcast
110.31.128.0/2510.31.128.1 – 10.31.128.12610.31.128.127
210.31.128.128/2510.31.128.129 – 10.31.128.25410.31.128.255
310.31.129.0/2510.31.129.1 – 10.31.129.12610.31.129.127
410.31.129.128/2510.31.129.129 – 10.31.129.25410.31.129.255
510.31.130.0/2510.31.130.1 – 10.31.130.12610.31.130.127
610.31.130.128/2510.31.130.129 – 10.31.130.25410.31.130.255
710.31.131.0/2510.31.131.1 – 10.31.131.12610.31.131.127
810.31.131.128/2510.31.131.129 – 10.31.131.25410.31.131.255
910.31.132.0/2510.31.132.1 – 10.31.132.12610.31.132.127
1010.31.132.128/2510.31.132.129 – 10.31.132.25410.31.132.255
1110.31.133.0/2510.31.133.1 – 10.31.133.12610.31.133.127
1210.31.133.128/2510.31.133.129 – 10.31.133.25410.31.133.255
1310.31.134.0/2510.31.134.1 – 10.31.134.12610.31.134.127
1410.31.134.128/2510.31.134.129 – 10.31.134.25410.31.134.255
1510.31.135.0/2510.31.135.1 – 10.31.135.12610.31.135.127
1610.31.135.128/2510.31.135.129 – 10.31.135.25410.31.135.255
1710.31.136.0/2510.31.136.1 – 10.31.136.12610.31.136.127
1810.31.136.128/2510.31.136.129 – 10.31.136.25410.31.136.255
1910.31.137.0/2510.31.137.1 – 10.31.137.12610.31.137.127
2010.31.137.128/2510.31.137.129 – 10.31.137.25410.31.137.255
2110.31.138.0/2510.31.138.1 – 10.31.138.12610.31.138.127
2210.31.138.128/2510.31.138.129 – 10.31.138.25410.31.138.255
2310.31.139.0/2510.31.139.1 – 10.31.139.12610.31.139.127
2410.31.139.128/2510.31.139.129 – 10.31.139.25410.31.139.255
2510.31.140.0/2510.31.140.1 – 10.31.140.12610.31.140.127
2610.31.140.128/2510.31.140.129 – 10.31.140.25410.31.140.255
2710.31.141.0/2510.31.141.1 – 10.31.141.12610.31.141.127
2810.31.141.128/2510.31.141.129 – 10.31.141.25410.31.141.255
2910.31.142.0/2510.31.142.1 – 10.31.142.12610.31.142.127
3010.31.142.128/2510.31.142.129 – 10.31.142.25410.31.142.255
3110.31.143.0/2510.31.143.1 – 10.31.143.12610.31.143.127
3210.31.143.128/2510.31.143.129 – 10.31.143.25410.31.143.255
3310.31.144.0/2510.31.144.1 – 10.31.144.12610.31.144.127
3410.31.144.128/2510.31.144.129 – 10.31.144.25410.31.144.255
3510.31.145.0/2510.31.145.1 – 10.31.145.12610.31.145.127
3610.31.145.128/2510.31.145.129 – 10.31.145.25410.31.145.255
3710.31.146.0/2510.31.146.1 – 10.31.146.12610.31.146.127
3810.31.146.128/2510.31.146.129 – 10.31.146.25410.31.146.255
3910.31.147.0/2510.31.147.1 – 10.31.147.12610.31.147.127
4010.31.147.128/2510.31.147.129 – 10.31.147.25410.31.147.255
4110.31.148.0/2510.31.148.1 – 10.31.148.12610.31.148.127
4210.31.148.128/2510.31.148.129 – 10.31.148.25410.31.148.255
4310.31.149.0/2510.31.149.1 – 10.31.149.12610.31.149.127
4410.31.149.128/2510.31.149.129 – 10.31.149.25410.31.149.255
4510.31.150.0/2510.31.150.1 – 10.31.150.12610.31.150.127
4610.31.150.128/2510.31.150.129 – 10.31.150.25410.31.150.255
4710.31.151.0/2510.31.151.1 – 10.31.151.12610.31.151.127
4810.31.151.128/2510.31.151.129 – 10.31.151.25410.31.151.255
4910.31.152.0/2510.31.152.1 – 10.31.152.12610.31.152.127
5010.31.152.128/2510.31.152.129 – 10.31.152.25410.31.152.255
5110.31.153.0/2510.31.153.1 – 10.31.153.12610.31.153.127
5210.31.153.128/2510.31.153.129 – 10.31.153.25410.31.153.255
5310.31.154.0/2510.31.154.1 – 10.31.154.12610.31.154.127
5410.31.154.128/2510.31.154.129 – 10.31.154.25410.31.154.255
5510.31.155.0/2510.31.155.1 – 10.31.155.12610.31.155.127
5610.31.155.128/2510.31.155.129 – 10.31.155.25410.31.155.255
5710.31.156.0/2510.31.156.1 – 10.31.156.12610.31.156.127
5810.31.156.128/2510.31.156.129 – 10.31.156.25410.31.156.255
5910.31.157.0/2510.31.157.1 – 10.31.157.12610.31.157.127
6010.31.157.128/2510.31.157.129 – 10.31.157.25410.31.157.255
6110.31.158.0/2510.31.158.1 – 10.31.158.12610.31.158.127
6210.31.158.128/2510.31.158.129 – 10.31.158.25410.31.158.255
6310.31.159.0/2510.31.159.1 – 10.31.159.12610.31.159.127
6410.31.159.128/2510.31.159.129 – 10.31.159.25410.31.159.255
01 / table

IPv4 CIDR prefix table.

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

prefixsubnet maskaddresseshostsin your /19
/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-
/18255.255.192.016,38416,382-
/19255.255.224.08,1928,1901
/20255.255.240.04,0964,0942 split →
/21255.255.248.02,0482,0464 split →
/22255.255.252.01,0241,0228 split →
/23255.255.254.051251016 split →
/24255.255.255.025625432 split →
/25255.255.255.12812812664 split →
/26255.255.255.1926462128 split →
/27255.255.255.2243230256 split →
/28255.255.255.2401614512 split →
/29255.255.255.248861,024 split →
/30255.255.255.252422,048 split →
/31255.255.255.254224,096 split →
/32255.255.255.255118,192 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 →