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
Try:192.168.1.10/2410.0.0.0/8172.16.5.4/20203.0.113.9/29
IPv6 calculator →
private IP (RFC 1918)10.78.112.0/21
network10.78.112.0/21
broadcast10.78.119.255
first host10.78.112.1
last host10.78.119.254
subnet mask255.255.248.0
wildcard0.0.7.255
addresses2,048
usable hosts2,046
classA
ipcalc 10.78.112.0/21
address00001010.01001110.01110000.00000000
subnet mask11111111.11111111.11111000.00000000
network00001010.01001110.01110000.00000000
broadcast00001010.01001110.01110111.11111111
green = network part, grey = host part
hex0x0a4e7000
decimal172912640
reverse dns0.112.78.10.in-addr.arpa
ipv4-mapped::ffff:a4e:7000

/21 split into /28 · 128 subnets

close ×
#networkhost rangebroadcast
110.78.112.0/2810.78.112.1 – 10.78.112.1410.78.112.15
210.78.112.16/2810.78.112.17 – 10.78.112.3010.78.112.31
310.78.112.32/2810.78.112.33 – 10.78.112.4610.78.112.47
410.78.112.48/2810.78.112.49 – 10.78.112.6210.78.112.63
510.78.112.64/2810.78.112.65 – 10.78.112.7810.78.112.79
610.78.112.80/2810.78.112.81 – 10.78.112.9410.78.112.95
710.78.112.96/2810.78.112.97 – 10.78.112.11010.78.112.111
810.78.112.112/2810.78.112.113 – 10.78.112.12610.78.112.127
910.78.112.128/2810.78.112.129 – 10.78.112.14210.78.112.143
1010.78.112.144/2810.78.112.145 – 10.78.112.15810.78.112.159
1110.78.112.160/2810.78.112.161 – 10.78.112.17410.78.112.175
1210.78.112.176/2810.78.112.177 – 10.78.112.19010.78.112.191
1310.78.112.192/2810.78.112.193 – 10.78.112.20610.78.112.207
1410.78.112.208/2810.78.112.209 – 10.78.112.22210.78.112.223
1510.78.112.224/2810.78.112.225 – 10.78.112.23810.78.112.239
1610.78.112.240/2810.78.112.241 – 10.78.112.25410.78.112.255
1710.78.113.0/2810.78.113.1 – 10.78.113.1410.78.113.15
1810.78.113.16/2810.78.113.17 – 10.78.113.3010.78.113.31
1910.78.113.32/2810.78.113.33 – 10.78.113.4610.78.113.47
2010.78.113.48/2810.78.113.49 – 10.78.113.6210.78.113.63
2110.78.113.64/2810.78.113.65 – 10.78.113.7810.78.113.79
2210.78.113.80/2810.78.113.81 – 10.78.113.9410.78.113.95
2310.78.113.96/2810.78.113.97 – 10.78.113.11010.78.113.111
2410.78.113.112/2810.78.113.113 – 10.78.113.12610.78.113.127
2510.78.113.128/2810.78.113.129 – 10.78.113.14210.78.113.143
2610.78.113.144/2810.78.113.145 – 10.78.113.15810.78.113.159
2710.78.113.160/2810.78.113.161 – 10.78.113.17410.78.113.175
2810.78.113.176/2810.78.113.177 – 10.78.113.19010.78.113.191
2910.78.113.192/2810.78.113.193 – 10.78.113.20610.78.113.207
3010.78.113.208/2810.78.113.209 – 10.78.113.22210.78.113.223
3110.78.113.224/2810.78.113.225 – 10.78.113.23810.78.113.239
3210.78.113.240/2810.78.113.241 – 10.78.113.25410.78.113.255
3310.78.114.0/2810.78.114.1 – 10.78.114.1410.78.114.15
3410.78.114.16/2810.78.114.17 – 10.78.114.3010.78.114.31
3510.78.114.32/2810.78.114.33 – 10.78.114.4610.78.114.47
3610.78.114.48/2810.78.114.49 – 10.78.114.6210.78.114.63
3710.78.114.64/2810.78.114.65 – 10.78.114.7810.78.114.79
3810.78.114.80/2810.78.114.81 – 10.78.114.9410.78.114.95
3910.78.114.96/2810.78.114.97 – 10.78.114.11010.78.114.111
4010.78.114.112/2810.78.114.113 – 10.78.114.12610.78.114.127
4110.78.114.128/2810.78.114.129 – 10.78.114.14210.78.114.143
4210.78.114.144/2810.78.114.145 – 10.78.114.15810.78.114.159
4310.78.114.160/2810.78.114.161 – 10.78.114.17410.78.114.175
4410.78.114.176/2810.78.114.177 – 10.78.114.19010.78.114.191
4510.78.114.192/2810.78.114.193 – 10.78.114.20610.78.114.207
4610.78.114.208/2810.78.114.209 – 10.78.114.22210.78.114.223
4710.78.114.224/2810.78.114.225 – 10.78.114.23810.78.114.239
4810.78.114.240/2810.78.114.241 – 10.78.114.25410.78.114.255
4910.78.115.0/2810.78.115.1 – 10.78.115.1410.78.115.15
5010.78.115.16/2810.78.115.17 – 10.78.115.3010.78.115.31
5110.78.115.32/2810.78.115.33 – 10.78.115.4610.78.115.47
5210.78.115.48/2810.78.115.49 – 10.78.115.6210.78.115.63
5310.78.115.64/2810.78.115.65 – 10.78.115.7810.78.115.79
5410.78.115.80/2810.78.115.81 – 10.78.115.9410.78.115.95
5510.78.115.96/2810.78.115.97 – 10.78.115.11010.78.115.111
5610.78.115.112/2810.78.115.113 – 10.78.115.12610.78.115.127
5710.78.115.128/2810.78.115.129 – 10.78.115.14210.78.115.143
5810.78.115.144/2810.78.115.145 – 10.78.115.15810.78.115.159
5910.78.115.160/2810.78.115.161 – 10.78.115.17410.78.115.175
6010.78.115.176/2810.78.115.177 – 10.78.115.19010.78.115.191
6110.78.115.192/2810.78.115.193 – 10.78.115.20610.78.115.207
6210.78.115.208/2810.78.115.209 – 10.78.115.22210.78.115.223
6310.78.115.224/2810.78.115.225 – 10.78.115.23810.78.115.239
6410.78.115.240/2810.78.115.241 – 10.78.115.25410.78.115.255
6510.78.116.0/2810.78.116.1 – 10.78.116.1410.78.116.15
6610.78.116.16/2810.78.116.17 – 10.78.116.3010.78.116.31
6710.78.116.32/2810.78.116.33 – 10.78.116.4610.78.116.47
6810.78.116.48/2810.78.116.49 – 10.78.116.6210.78.116.63
6910.78.116.64/2810.78.116.65 – 10.78.116.7810.78.116.79
7010.78.116.80/2810.78.116.81 – 10.78.116.9410.78.116.95
7110.78.116.96/2810.78.116.97 – 10.78.116.11010.78.116.111
7210.78.116.112/2810.78.116.113 – 10.78.116.12610.78.116.127
7310.78.116.128/2810.78.116.129 – 10.78.116.14210.78.116.143
7410.78.116.144/2810.78.116.145 – 10.78.116.15810.78.116.159
7510.78.116.160/2810.78.116.161 – 10.78.116.17410.78.116.175
7610.78.116.176/2810.78.116.177 – 10.78.116.19010.78.116.191
7710.78.116.192/2810.78.116.193 – 10.78.116.20610.78.116.207
7810.78.116.208/2810.78.116.209 – 10.78.116.22210.78.116.223
7910.78.116.224/2810.78.116.225 – 10.78.116.23810.78.116.239
8010.78.116.240/2810.78.116.241 – 10.78.116.25410.78.116.255
8110.78.117.0/2810.78.117.1 – 10.78.117.1410.78.117.15
8210.78.117.16/2810.78.117.17 – 10.78.117.3010.78.117.31
8310.78.117.32/2810.78.117.33 – 10.78.117.4610.78.117.47
8410.78.117.48/2810.78.117.49 – 10.78.117.6210.78.117.63
8510.78.117.64/2810.78.117.65 – 10.78.117.7810.78.117.79
8610.78.117.80/2810.78.117.81 – 10.78.117.9410.78.117.95
8710.78.117.96/2810.78.117.97 – 10.78.117.11010.78.117.111
8810.78.117.112/2810.78.117.113 – 10.78.117.12610.78.117.127
8910.78.117.128/2810.78.117.129 – 10.78.117.14210.78.117.143
9010.78.117.144/2810.78.117.145 – 10.78.117.15810.78.117.159
9110.78.117.160/2810.78.117.161 – 10.78.117.17410.78.117.175
9210.78.117.176/2810.78.117.177 – 10.78.117.19010.78.117.191
9310.78.117.192/2810.78.117.193 – 10.78.117.20610.78.117.207
9410.78.117.208/2810.78.117.209 – 10.78.117.22210.78.117.223
9510.78.117.224/2810.78.117.225 – 10.78.117.23810.78.117.239
9610.78.117.240/2810.78.117.241 – 10.78.117.25410.78.117.255
9710.78.118.0/2810.78.118.1 – 10.78.118.1410.78.118.15
9810.78.118.16/2810.78.118.17 – 10.78.118.3010.78.118.31
9910.78.118.32/2810.78.118.33 – 10.78.118.4610.78.118.47
10010.78.118.48/2810.78.118.49 – 10.78.118.6210.78.118.63
10110.78.118.64/2810.78.118.65 – 10.78.118.7810.78.118.79
10210.78.118.80/2810.78.118.81 – 10.78.118.9410.78.118.95
10310.78.118.96/2810.78.118.97 – 10.78.118.11010.78.118.111
10410.78.118.112/2810.78.118.113 – 10.78.118.12610.78.118.127
10510.78.118.128/2810.78.118.129 – 10.78.118.14210.78.118.143
10610.78.118.144/2810.78.118.145 – 10.78.118.15810.78.118.159
10710.78.118.160/2810.78.118.161 – 10.78.118.17410.78.118.175
10810.78.118.176/2810.78.118.177 – 10.78.118.19010.78.118.191
10910.78.118.192/2810.78.118.193 – 10.78.118.20610.78.118.207
11010.78.118.208/2810.78.118.209 – 10.78.118.22210.78.118.223
11110.78.118.224/2810.78.118.225 – 10.78.118.23810.78.118.239
11210.78.118.240/2810.78.118.241 – 10.78.118.25410.78.118.255
11310.78.119.0/2810.78.119.1 – 10.78.119.1410.78.119.15
11410.78.119.16/2810.78.119.17 – 10.78.119.3010.78.119.31
11510.78.119.32/2810.78.119.33 – 10.78.119.4610.78.119.47
11610.78.119.48/2810.78.119.49 – 10.78.119.6210.78.119.63
11710.78.119.64/2810.78.119.65 – 10.78.119.7810.78.119.79
11810.78.119.80/2810.78.119.81 – 10.78.119.9410.78.119.95
11910.78.119.96/2810.78.119.97 – 10.78.119.11010.78.119.111
12010.78.119.112/2810.78.119.113 – 10.78.119.12610.78.119.127
12110.78.119.128/2810.78.119.129 – 10.78.119.14210.78.119.143
12210.78.119.144/2810.78.119.145 – 10.78.119.15810.78.119.159
12310.78.119.160/2810.78.119.161 – 10.78.119.17410.78.119.175
12410.78.119.176/2810.78.119.177 – 10.78.119.19010.78.119.191
12510.78.119.192/2810.78.119.193 – 10.78.119.20610.78.119.207
12610.78.119.208/2810.78.119.209 – 10.78.119.22210.78.119.223
12710.78.119.224/2810.78.119.225 – 10.78.119.23810.78.119.239
12810.78.119.240/2810.78.119.241 – 10.78.119.25410.78.119.255
01 / table

IPv4 CIDR prefix table.

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

prefixsubnet maskaddresseshostsin your /21
/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-
/20255.255.240.04,0964,094-
/21255.255.248.02,0482,0461
/22255.255.252.01,0241,0222 split →
/23255.255.254.05125104 split →
/24255.255.255.02562548 split →
/25255.255.255.12812812616 split →
/26255.255.255.192646232 split →
/27255.255.255.224323064 split →
/28255.255.255.2401614128 split →
/29255.255.255.24886256 split →
/30255.255.255.25242512 split →
/31255.255.255.254221,024 split →
/32255.255.255.255112,048 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 →