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)10.7.216.0/21
network10.7.216.0/21
broadcast10.7.223.255
first host10.7.216.1
last host10.7.223.254
subnet mask255.255.248.0
wildcard0.0.7.255
addresses2,048
usable hosts2,046
classA
ipcalc 10.7.216.0/21
address00001010.00000111.11011000.00000000
subnet mask11111111.11111111.11111000.00000000
network00001010.00000111.11011000.00000000
broadcast00001010.00000111.11011111.11111111
green = network part, grey = host part
hex0x0a07d800
decimal168286208
reverse dns0.216.7.10.in-addr.arpa
ipv4-mapped::ffff:a07:d800

/21 split into /28 · 128 subnets

close ×
#networkhost rangebroadcast
110.7.216.0/2810.7.216.1 – 10.7.216.1410.7.216.15
210.7.216.16/2810.7.216.17 – 10.7.216.3010.7.216.31
310.7.216.32/2810.7.216.33 – 10.7.216.4610.7.216.47
410.7.216.48/2810.7.216.49 – 10.7.216.6210.7.216.63
510.7.216.64/2810.7.216.65 – 10.7.216.7810.7.216.79
610.7.216.80/2810.7.216.81 – 10.7.216.9410.7.216.95
710.7.216.96/2810.7.216.97 – 10.7.216.11010.7.216.111
810.7.216.112/2810.7.216.113 – 10.7.216.12610.7.216.127
910.7.216.128/2810.7.216.129 – 10.7.216.14210.7.216.143
1010.7.216.144/2810.7.216.145 – 10.7.216.15810.7.216.159
1110.7.216.160/2810.7.216.161 – 10.7.216.17410.7.216.175
1210.7.216.176/2810.7.216.177 – 10.7.216.19010.7.216.191
1310.7.216.192/2810.7.216.193 – 10.7.216.20610.7.216.207
1410.7.216.208/2810.7.216.209 – 10.7.216.22210.7.216.223
1510.7.216.224/2810.7.216.225 – 10.7.216.23810.7.216.239
1610.7.216.240/2810.7.216.241 – 10.7.216.25410.7.216.255
1710.7.217.0/2810.7.217.1 – 10.7.217.1410.7.217.15
1810.7.217.16/2810.7.217.17 – 10.7.217.3010.7.217.31
1910.7.217.32/2810.7.217.33 – 10.7.217.4610.7.217.47
2010.7.217.48/2810.7.217.49 – 10.7.217.6210.7.217.63
2110.7.217.64/2810.7.217.65 – 10.7.217.7810.7.217.79
2210.7.217.80/2810.7.217.81 – 10.7.217.9410.7.217.95
2310.7.217.96/2810.7.217.97 – 10.7.217.11010.7.217.111
2410.7.217.112/2810.7.217.113 – 10.7.217.12610.7.217.127
2510.7.217.128/2810.7.217.129 – 10.7.217.14210.7.217.143
2610.7.217.144/2810.7.217.145 – 10.7.217.15810.7.217.159
2710.7.217.160/2810.7.217.161 – 10.7.217.17410.7.217.175
2810.7.217.176/2810.7.217.177 – 10.7.217.19010.7.217.191
2910.7.217.192/2810.7.217.193 – 10.7.217.20610.7.217.207
3010.7.217.208/2810.7.217.209 – 10.7.217.22210.7.217.223
3110.7.217.224/2810.7.217.225 – 10.7.217.23810.7.217.239
3210.7.217.240/2810.7.217.241 – 10.7.217.25410.7.217.255
3310.7.218.0/2810.7.218.1 – 10.7.218.1410.7.218.15
3410.7.218.16/2810.7.218.17 – 10.7.218.3010.7.218.31
3510.7.218.32/2810.7.218.33 – 10.7.218.4610.7.218.47
3610.7.218.48/2810.7.218.49 – 10.7.218.6210.7.218.63
3710.7.218.64/2810.7.218.65 – 10.7.218.7810.7.218.79
3810.7.218.80/2810.7.218.81 – 10.7.218.9410.7.218.95
3910.7.218.96/2810.7.218.97 – 10.7.218.11010.7.218.111
4010.7.218.112/2810.7.218.113 – 10.7.218.12610.7.218.127
4110.7.218.128/2810.7.218.129 – 10.7.218.14210.7.218.143
4210.7.218.144/2810.7.218.145 – 10.7.218.15810.7.218.159
4310.7.218.160/2810.7.218.161 – 10.7.218.17410.7.218.175
4410.7.218.176/2810.7.218.177 – 10.7.218.19010.7.218.191
4510.7.218.192/2810.7.218.193 – 10.7.218.20610.7.218.207
4610.7.218.208/2810.7.218.209 – 10.7.218.22210.7.218.223
4710.7.218.224/2810.7.218.225 – 10.7.218.23810.7.218.239
4810.7.218.240/2810.7.218.241 – 10.7.218.25410.7.218.255
4910.7.219.0/2810.7.219.1 – 10.7.219.1410.7.219.15
5010.7.219.16/2810.7.219.17 – 10.7.219.3010.7.219.31
5110.7.219.32/2810.7.219.33 – 10.7.219.4610.7.219.47
5210.7.219.48/2810.7.219.49 – 10.7.219.6210.7.219.63
5310.7.219.64/2810.7.219.65 – 10.7.219.7810.7.219.79
5410.7.219.80/2810.7.219.81 – 10.7.219.9410.7.219.95
5510.7.219.96/2810.7.219.97 – 10.7.219.11010.7.219.111
5610.7.219.112/2810.7.219.113 – 10.7.219.12610.7.219.127
5710.7.219.128/2810.7.219.129 – 10.7.219.14210.7.219.143
5810.7.219.144/2810.7.219.145 – 10.7.219.15810.7.219.159
5910.7.219.160/2810.7.219.161 – 10.7.219.17410.7.219.175
6010.7.219.176/2810.7.219.177 – 10.7.219.19010.7.219.191
6110.7.219.192/2810.7.219.193 – 10.7.219.20610.7.219.207
6210.7.219.208/2810.7.219.209 – 10.7.219.22210.7.219.223
6310.7.219.224/2810.7.219.225 – 10.7.219.23810.7.219.239
6410.7.219.240/2810.7.219.241 – 10.7.219.25410.7.219.255
6510.7.220.0/2810.7.220.1 – 10.7.220.1410.7.220.15
6610.7.220.16/2810.7.220.17 – 10.7.220.3010.7.220.31
6710.7.220.32/2810.7.220.33 – 10.7.220.4610.7.220.47
6810.7.220.48/2810.7.220.49 – 10.7.220.6210.7.220.63
6910.7.220.64/2810.7.220.65 – 10.7.220.7810.7.220.79
7010.7.220.80/2810.7.220.81 – 10.7.220.9410.7.220.95
7110.7.220.96/2810.7.220.97 – 10.7.220.11010.7.220.111
7210.7.220.112/2810.7.220.113 – 10.7.220.12610.7.220.127
7310.7.220.128/2810.7.220.129 – 10.7.220.14210.7.220.143
7410.7.220.144/2810.7.220.145 – 10.7.220.15810.7.220.159
7510.7.220.160/2810.7.220.161 – 10.7.220.17410.7.220.175
7610.7.220.176/2810.7.220.177 – 10.7.220.19010.7.220.191
7710.7.220.192/2810.7.220.193 – 10.7.220.20610.7.220.207
7810.7.220.208/2810.7.220.209 – 10.7.220.22210.7.220.223
7910.7.220.224/2810.7.220.225 – 10.7.220.23810.7.220.239
8010.7.220.240/2810.7.220.241 – 10.7.220.25410.7.220.255
8110.7.221.0/2810.7.221.1 – 10.7.221.1410.7.221.15
8210.7.221.16/2810.7.221.17 – 10.7.221.3010.7.221.31
8310.7.221.32/2810.7.221.33 – 10.7.221.4610.7.221.47
8410.7.221.48/2810.7.221.49 – 10.7.221.6210.7.221.63
8510.7.221.64/2810.7.221.65 – 10.7.221.7810.7.221.79
8610.7.221.80/2810.7.221.81 – 10.7.221.9410.7.221.95
8710.7.221.96/2810.7.221.97 – 10.7.221.11010.7.221.111
8810.7.221.112/2810.7.221.113 – 10.7.221.12610.7.221.127
8910.7.221.128/2810.7.221.129 – 10.7.221.14210.7.221.143
9010.7.221.144/2810.7.221.145 – 10.7.221.15810.7.221.159
9110.7.221.160/2810.7.221.161 – 10.7.221.17410.7.221.175
9210.7.221.176/2810.7.221.177 – 10.7.221.19010.7.221.191
9310.7.221.192/2810.7.221.193 – 10.7.221.20610.7.221.207
9410.7.221.208/2810.7.221.209 – 10.7.221.22210.7.221.223
9510.7.221.224/2810.7.221.225 – 10.7.221.23810.7.221.239
9610.7.221.240/2810.7.221.241 – 10.7.221.25410.7.221.255
9710.7.222.0/2810.7.222.1 – 10.7.222.1410.7.222.15
9810.7.222.16/2810.7.222.17 – 10.7.222.3010.7.222.31
9910.7.222.32/2810.7.222.33 – 10.7.222.4610.7.222.47
10010.7.222.48/2810.7.222.49 – 10.7.222.6210.7.222.63
10110.7.222.64/2810.7.222.65 – 10.7.222.7810.7.222.79
10210.7.222.80/2810.7.222.81 – 10.7.222.9410.7.222.95
10310.7.222.96/2810.7.222.97 – 10.7.222.11010.7.222.111
10410.7.222.112/2810.7.222.113 – 10.7.222.12610.7.222.127
10510.7.222.128/2810.7.222.129 – 10.7.222.14210.7.222.143
10610.7.222.144/2810.7.222.145 – 10.7.222.15810.7.222.159
10710.7.222.160/2810.7.222.161 – 10.7.222.17410.7.222.175
10810.7.222.176/2810.7.222.177 – 10.7.222.19010.7.222.191
10910.7.222.192/2810.7.222.193 – 10.7.222.20610.7.222.207
11010.7.222.208/2810.7.222.209 – 10.7.222.22210.7.222.223
11110.7.222.224/2810.7.222.225 – 10.7.222.23810.7.222.239
11210.7.222.240/2810.7.222.241 – 10.7.222.25410.7.222.255
11310.7.223.0/2810.7.223.1 – 10.7.223.1410.7.223.15
11410.7.223.16/2810.7.223.17 – 10.7.223.3010.7.223.31
11510.7.223.32/2810.7.223.33 – 10.7.223.4610.7.223.47
11610.7.223.48/2810.7.223.49 – 10.7.223.6210.7.223.63
11710.7.223.64/2810.7.223.65 – 10.7.223.7810.7.223.79
11810.7.223.80/2810.7.223.81 – 10.7.223.9410.7.223.95
11910.7.223.96/2810.7.223.97 – 10.7.223.11010.7.223.111
12010.7.223.112/2810.7.223.113 – 10.7.223.12610.7.223.127
12110.7.223.128/2810.7.223.129 – 10.7.223.14210.7.223.143
12210.7.223.144/2810.7.223.145 – 10.7.223.15810.7.223.159
12310.7.223.160/2810.7.223.161 – 10.7.223.17410.7.223.175
12410.7.223.176/2810.7.223.177 – 10.7.223.19010.7.223.191
12510.7.223.192/2810.7.223.193 – 10.7.223.20610.7.223.207
12610.7.223.208/2810.7.223.209 – 10.7.223.22210.7.223.223
12710.7.223.224/2810.7.223.225 – 10.7.223.23810.7.223.239
12810.7.223.240/2810.7.223.241 – 10.7.223.25410.7.223.255
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 →