ip
ipku.in

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
private IP (RFC 1918)10.12.208.0/20
network10.12.208.0/20
broadcast10.12.223.255
first host10.12.208.1
last host10.12.223.254
subnet mask255.255.240.0
wildcard0.0.15.255
addresses4,096
usable hosts4,094
classA
ipcalc 10.12.208.0/20
address00001010.00001100.11010000.00000000
subnet mask11111111.11111111.11110000.00000000
network00001010.00001100.11010000.00000000
broadcast00001010.00001100.11011111.11111111
green = network part, grey = host part
hex0x0a0cd000
decimal168611840
reverse dns0.208.12.10.in-addr.arpa
ipv4-mapped::ffff:a0c:d000

/20 split into /27 · 128 subnets

close ×
#networkhost rangebroadcast
110.12.208.0/2710.12.208.1 – 10.12.208.3010.12.208.31
210.12.208.32/2710.12.208.33 – 10.12.208.6210.12.208.63
310.12.208.64/2710.12.208.65 – 10.12.208.9410.12.208.95
410.12.208.96/2710.12.208.97 – 10.12.208.12610.12.208.127
510.12.208.128/2710.12.208.129 – 10.12.208.15810.12.208.159
610.12.208.160/2710.12.208.161 – 10.12.208.19010.12.208.191
710.12.208.192/2710.12.208.193 – 10.12.208.22210.12.208.223
810.12.208.224/2710.12.208.225 – 10.12.208.25410.12.208.255
910.12.209.0/2710.12.209.1 – 10.12.209.3010.12.209.31
1010.12.209.32/2710.12.209.33 – 10.12.209.6210.12.209.63
1110.12.209.64/2710.12.209.65 – 10.12.209.9410.12.209.95
1210.12.209.96/2710.12.209.97 – 10.12.209.12610.12.209.127
1310.12.209.128/2710.12.209.129 – 10.12.209.15810.12.209.159
1410.12.209.160/2710.12.209.161 – 10.12.209.19010.12.209.191
1510.12.209.192/2710.12.209.193 – 10.12.209.22210.12.209.223
1610.12.209.224/2710.12.209.225 – 10.12.209.25410.12.209.255
1710.12.210.0/2710.12.210.1 – 10.12.210.3010.12.210.31
1810.12.210.32/2710.12.210.33 – 10.12.210.6210.12.210.63
1910.12.210.64/2710.12.210.65 – 10.12.210.9410.12.210.95
2010.12.210.96/2710.12.210.97 – 10.12.210.12610.12.210.127
2110.12.210.128/2710.12.210.129 – 10.12.210.15810.12.210.159
2210.12.210.160/2710.12.210.161 – 10.12.210.19010.12.210.191
2310.12.210.192/2710.12.210.193 – 10.12.210.22210.12.210.223
2410.12.210.224/2710.12.210.225 – 10.12.210.25410.12.210.255
2510.12.211.0/2710.12.211.1 – 10.12.211.3010.12.211.31
2610.12.211.32/2710.12.211.33 – 10.12.211.6210.12.211.63
2710.12.211.64/2710.12.211.65 – 10.12.211.9410.12.211.95
2810.12.211.96/2710.12.211.97 – 10.12.211.12610.12.211.127
2910.12.211.128/2710.12.211.129 – 10.12.211.15810.12.211.159
3010.12.211.160/2710.12.211.161 – 10.12.211.19010.12.211.191
3110.12.211.192/2710.12.211.193 – 10.12.211.22210.12.211.223
3210.12.211.224/2710.12.211.225 – 10.12.211.25410.12.211.255
3310.12.212.0/2710.12.212.1 – 10.12.212.3010.12.212.31
3410.12.212.32/2710.12.212.33 – 10.12.212.6210.12.212.63
3510.12.212.64/2710.12.212.65 – 10.12.212.9410.12.212.95
3610.12.212.96/2710.12.212.97 – 10.12.212.12610.12.212.127
3710.12.212.128/2710.12.212.129 – 10.12.212.15810.12.212.159
3810.12.212.160/2710.12.212.161 – 10.12.212.19010.12.212.191
3910.12.212.192/2710.12.212.193 – 10.12.212.22210.12.212.223
4010.12.212.224/2710.12.212.225 – 10.12.212.25410.12.212.255
4110.12.213.0/2710.12.213.1 – 10.12.213.3010.12.213.31
4210.12.213.32/2710.12.213.33 – 10.12.213.6210.12.213.63
4310.12.213.64/2710.12.213.65 – 10.12.213.9410.12.213.95
4410.12.213.96/2710.12.213.97 – 10.12.213.12610.12.213.127
4510.12.213.128/2710.12.213.129 – 10.12.213.15810.12.213.159
4610.12.213.160/2710.12.213.161 – 10.12.213.19010.12.213.191
4710.12.213.192/2710.12.213.193 – 10.12.213.22210.12.213.223
4810.12.213.224/2710.12.213.225 – 10.12.213.25410.12.213.255
4910.12.214.0/2710.12.214.1 – 10.12.214.3010.12.214.31
5010.12.214.32/2710.12.214.33 – 10.12.214.6210.12.214.63
5110.12.214.64/2710.12.214.65 – 10.12.214.9410.12.214.95
5210.12.214.96/2710.12.214.97 – 10.12.214.12610.12.214.127
5310.12.214.128/2710.12.214.129 – 10.12.214.15810.12.214.159
5410.12.214.160/2710.12.214.161 – 10.12.214.19010.12.214.191
5510.12.214.192/2710.12.214.193 – 10.12.214.22210.12.214.223
5610.12.214.224/2710.12.214.225 – 10.12.214.25410.12.214.255
5710.12.215.0/2710.12.215.1 – 10.12.215.3010.12.215.31
5810.12.215.32/2710.12.215.33 – 10.12.215.6210.12.215.63
5910.12.215.64/2710.12.215.65 – 10.12.215.9410.12.215.95
6010.12.215.96/2710.12.215.97 – 10.12.215.12610.12.215.127
6110.12.215.128/2710.12.215.129 – 10.12.215.15810.12.215.159
6210.12.215.160/2710.12.215.161 – 10.12.215.19010.12.215.191
6310.12.215.192/2710.12.215.193 – 10.12.215.22210.12.215.223
6410.12.215.224/2710.12.215.225 – 10.12.215.25410.12.215.255
6510.12.216.0/2710.12.216.1 – 10.12.216.3010.12.216.31
6610.12.216.32/2710.12.216.33 – 10.12.216.6210.12.216.63
6710.12.216.64/2710.12.216.65 – 10.12.216.9410.12.216.95
6810.12.216.96/2710.12.216.97 – 10.12.216.12610.12.216.127
6910.12.216.128/2710.12.216.129 – 10.12.216.15810.12.216.159
7010.12.216.160/2710.12.216.161 – 10.12.216.19010.12.216.191
7110.12.216.192/2710.12.216.193 – 10.12.216.22210.12.216.223
7210.12.216.224/2710.12.216.225 – 10.12.216.25410.12.216.255
7310.12.217.0/2710.12.217.1 – 10.12.217.3010.12.217.31
7410.12.217.32/2710.12.217.33 – 10.12.217.6210.12.217.63
7510.12.217.64/2710.12.217.65 – 10.12.217.9410.12.217.95
7610.12.217.96/2710.12.217.97 – 10.12.217.12610.12.217.127
7710.12.217.128/2710.12.217.129 – 10.12.217.15810.12.217.159
7810.12.217.160/2710.12.217.161 – 10.12.217.19010.12.217.191
7910.12.217.192/2710.12.217.193 – 10.12.217.22210.12.217.223
8010.12.217.224/2710.12.217.225 – 10.12.217.25410.12.217.255
8110.12.218.0/2710.12.218.1 – 10.12.218.3010.12.218.31
8210.12.218.32/2710.12.218.33 – 10.12.218.6210.12.218.63
8310.12.218.64/2710.12.218.65 – 10.12.218.9410.12.218.95
8410.12.218.96/2710.12.218.97 – 10.12.218.12610.12.218.127
8510.12.218.128/2710.12.218.129 – 10.12.218.15810.12.218.159
8610.12.218.160/2710.12.218.161 – 10.12.218.19010.12.218.191
8710.12.218.192/2710.12.218.193 – 10.12.218.22210.12.218.223
8810.12.218.224/2710.12.218.225 – 10.12.218.25410.12.218.255
8910.12.219.0/2710.12.219.1 – 10.12.219.3010.12.219.31
9010.12.219.32/2710.12.219.33 – 10.12.219.6210.12.219.63
9110.12.219.64/2710.12.219.65 – 10.12.219.9410.12.219.95
9210.12.219.96/2710.12.219.97 – 10.12.219.12610.12.219.127
9310.12.219.128/2710.12.219.129 – 10.12.219.15810.12.219.159
9410.12.219.160/2710.12.219.161 – 10.12.219.19010.12.219.191
9510.12.219.192/2710.12.219.193 – 10.12.219.22210.12.219.223
9610.12.219.224/2710.12.219.225 – 10.12.219.25410.12.219.255
9710.12.220.0/2710.12.220.1 – 10.12.220.3010.12.220.31
9810.12.220.32/2710.12.220.33 – 10.12.220.6210.12.220.63
9910.12.220.64/2710.12.220.65 – 10.12.220.9410.12.220.95
10010.12.220.96/2710.12.220.97 – 10.12.220.12610.12.220.127
10110.12.220.128/2710.12.220.129 – 10.12.220.15810.12.220.159
10210.12.220.160/2710.12.220.161 – 10.12.220.19010.12.220.191
10310.12.220.192/2710.12.220.193 – 10.12.220.22210.12.220.223
10410.12.220.224/2710.12.220.225 – 10.12.220.25410.12.220.255
10510.12.221.0/2710.12.221.1 – 10.12.221.3010.12.221.31
10610.12.221.32/2710.12.221.33 – 10.12.221.6210.12.221.63
10710.12.221.64/2710.12.221.65 – 10.12.221.9410.12.221.95
10810.12.221.96/2710.12.221.97 – 10.12.221.12610.12.221.127
10910.12.221.128/2710.12.221.129 – 10.12.221.15810.12.221.159
11010.12.221.160/2710.12.221.161 – 10.12.221.19010.12.221.191
11110.12.221.192/2710.12.221.193 – 10.12.221.22210.12.221.223
11210.12.221.224/2710.12.221.225 – 10.12.221.25410.12.221.255
11310.12.222.0/2710.12.222.1 – 10.12.222.3010.12.222.31
11410.12.222.32/2710.12.222.33 – 10.12.222.6210.12.222.63
11510.12.222.64/2710.12.222.65 – 10.12.222.9410.12.222.95
11610.12.222.96/2710.12.222.97 – 10.12.222.12610.12.222.127
11710.12.222.128/2710.12.222.129 – 10.12.222.15810.12.222.159
11810.12.222.160/2710.12.222.161 – 10.12.222.19010.12.222.191
11910.12.222.192/2710.12.222.193 – 10.12.222.22210.12.222.223
12010.12.222.224/2710.12.222.225 – 10.12.222.25410.12.222.255
12110.12.223.0/2710.12.223.1 – 10.12.223.3010.12.223.31
12210.12.223.32/2710.12.223.33 – 10.12.223.6210.12.223.63
12310.12.223.64/2710.12.223.65 – 10.12.223.9410.12.223.95
12410.12.223.96/2710.12.223.97 – 10.12.223.12610.12.223.127
12510.12.223.128/2710.12.223.129 – 10.12.223.15810.12.223.159
12610.12.223.160/2710.12.223.161 – 10.12.223.19010.12.223.191
12710.12.223.192/2710.12.223.193 – 10.12.223.22210.12.223.223
12810.12.223.224/2710.12.223.225 – 10.12.223.25410.12.223.255
01 / table

IPv4 CIDR prefix table.

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

prefixsubnet maskaddresseshostsin your /20
/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-
/19255.255.224.08,1928,190-
/20255.255.240.04,0964,0941
/21255.255.248.02,0482,0462 split →
/22255.255.252.01,0241,0224 split →
/23255.255.254.05125108 split →
/24255.255.255.025625416 split →
/25255.255.255.12812812632 split →
/26255.255.255.192646264 split →
/27255.255.255.2243230128 split →
/28255.255.255.2401614256 split →
/29255.255.255.24886512 split →
/30255.255.255.252421,024 split →
/31255.255.255.254222,048 split →
/32255.255.255.255114,096 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 →