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)10.167.216.0/21
network10.167.216.0/21
broadcast10.167.223.255
first host10.167.216.1
last host10.167.223.254
subnet mask255.255.248.0
wildcard0.0.7.255
addresses2,048
usable hosts2,046
classA
ipcalc 10.167.216.0/21
address00001010.10100111.11011000.00000000
subnet mask11111111.11111111.11111000.00000000
network00001010.10100111.11011000.00000000
broadcast00001010.10100111.11011111.11111111
green = network part, grey = host part
hex0x0aa7d800
decimal178771968
reverse dns0.216.167.10.in-addr.arpa
ipv4-mapped::ffff:aa7:d800

/21 split into /28 · 128 subnets

close ×
#networkhost rangebroadcast
110.167.216.0/2810.167.216.1 – 10.167.216.1410.167.216.15
210.167.216.16/2810.167.216.17 – 10.167.216.3010.167.216.31
310.167.216.32/2810.167.216.33 – 10.167.216.4610.167.216.47
410.167.216.48/2810.167.216.49 – 10.167.216.6210.167.216.63
510.167.216.64/2810.167.216.65 – 10.167.216.7810.167.216.79
610.167.216.80/2810.167.216.81 – 10.167.216.9410.167.216.95
710.167.216.96/2810.167.216.97 – 10.167.216.11010.167.216.111
810.167.216.112/2810.167.216.113 – 10.167.216.12610.167.216.127
910.167.216.128/2810.167.216.129 – 10.167.216.14210.167.216.143
1010.167.216.144/2810.167.216.145 – 10.167.216.15810.167.216.159
1110.167.216.160/2810.167.216.161 – 10.167.216.17410.167.216.175
1210.167.216.176/2810.167.216.177 – 10.167.216.19010.167.216.191
1310.167.216.192/2810.167.216.193 – 10.167.216.20610.167.216.207
1410.167.216.208/2810.167.216.209 – 10.167.216.22210.167.216.223
1510.167.216.224/2810.167.216.225 – 10.167.216.23810.167.216.239
1610.167.216.240/2810.167.216.241 – 10.167.216.25410.167.216.255
1710.167.217.0/2810.167.217.1 – 10.167.217.1410.167.217.15
1810.167.217.16/2810.167.217.17 – 10.167.217.3010.167.217.31
1910.167.217.32/2810.167.217.33 – 10.167.217.4610.167.217.47
2010.167.217.48/2810.167.217.49 – 10.167.217.6210.167.217.63
2110.167.217.64/2810.167.217.65 – 10.167.217.7810.167.217.79
2210.167.217.80/2810.167.217.81 – 10.167.217.9410.167.217.95
2310.167.217.96/2810.167.217.97 – 10.167.217.11010.167.217.111
2410.167.217.112/2810.167.217.113 – 10.167.217.12610.167.217.127
2510.167.217.128/2810.167.217.129 – 10.167.217.14210.167.217.143
2610.167.217.144/2810.167.217.145 – 10.167.217.15810.167.217.159
2710.167.217.160/2810.167.217.161 – 10.167.217.17410.167.217.175
2810.167.217.176/2810.167.217.177 – 10.167.217.19010.167.217.191
2910.167.217.192/2810.167.217.193 – 10.167.217.20610.167.217.207
3010.167.217.208/2810.167.217.209 – 10.167.217.22210.167.217.223
3110.167.217.224/2810.167.217.225 – 10.167.217.23810.167.217.239
3210.167.217.240/2810.167.217.241 – 10.167.217.25410.167.217.255
3310.167.218.0/2810.167.218.1 – 10.167.218.1410.167.218.15
3410.167.218.16/2810.167.218.17 – 10.167.218.3010.167.218.31
3510.167.218.32/2810.167.218.33 – 10.167.218.4610.167.218.47
3610.167.218.48/2810.167.218.49 – 10.167.218.6210.167.218.63
3710.167.218.64/2810.167.218.65 – 10.167.218.7810.167.218.79
3810.167.218.80/2810.167.218.81 – 10.167.218.9410.167.218.95
3910.167.218.96/2810.167.218.97 – 10.167.218.11010.167.218.111
4010.167.218.112/2810.167.218.113 – 10.167.218.12610.167.218.127
4110.167.218.128/2810.167.218.129 – 10.167.218.14210.167.218.143
4210.167.218.144/2810.167.218.145 – 10.167.218.15810.167.218.159
4310.167.218.160/2810.167.218.161 – 10.167.218.17410.167.218.175
4410.167.218.176/2810.167.218.177 – 10.167.218.19010.167.218.191
4510.167.218.192/2810.167.218.193 – 10.167.218.20610.167.218.207
4610.167.218.208/2810.167.218.209 – 10.167.218.22210.167.218.223
4710.167.218.224/2810.167.218.225 – 10.167.218.23810.167.218.239
4810.167.218.240/2810.167.218.241 – 10.167.218.25410.167.218.255
4910.167.219.0/2810.167.219.1 – 10.167.219.1410.167.219.15
5010.167.219.16/2810.167.219.17 – 10.167.219.3010.167.219.31
5110.167.219.32/2810.167.219.33 – 10.167.219.4610.167.219.47
5210.167.219.48/2810.167.219.49 – 10.167.219.6210.167.219.63
5310.167.219.64/2810.167.219.65 – 10.167.219.7810.167.219.79
5410.167.219.80/2810.167.219.81 – 10.167.219.9410.167.219.95
5510.167.219.96/2810.167.219.97 – 10.167.219.11010.167.219.111
5610.167.219.112/2810.167.219.113 – 10.167.219.12610.167.219.127
5710.167.219.128/2810.167.219.129 – 10.167.219.14210.167.219.143
5810.167.219.144/2810.167.219.145 – 10.167.219.15810.167.219.159
5910.167.219.160/2810.167.219.161 – 10.167.219.17410.167.219.175
6010.167.219.176/2810.167.219.177 – 10.167.219.19010.167.219.191
6110.167.219.192/2810.167.219.193 – 10.167.219.20610.167.219.207
6210.167.219.208/2810.167.219.209 – 10.167.219.22210.167.219.223
6310.167.219.224/2810.167.219.225 – 10.167.219.23810.167.219.239
6410.167.219.240/2810.167.219.241 – 10.167.219.25410.167.219.255
6510.167.220.0/2810.167.220.1 – 10.167.220.1410.167.220.15
6610.167.220.16/2810.167.220.17 – 10.167.220.3010.167.220.31
6710.167.220.32/2810.167.220.33 – 10.167.220.4610.167.220.47
6810.167.220.48/2810.167.220.49 – 10.167.220.6210.167.220.63
6910.167.220.64/2810.167.220.65 – 10.167.220.7810.167.220.79
7010.167.220.80/2810.167.220.81 – 10.167.220.9410.167.220.95
7110.167.220.96/2810.167.220.97 – 10.167.220.11010.167.220.111
7210.167.220.112/2810.167.220.113 – 10.167.220.12610.167.220.127
7310.167.220.128/2810.167.220.129 – 10.167.220.14210.167.220.143
7410.167.220.144/2810.167.220.145 – 10.167.220.15810.167.220.159
7510.167.220.160/2810.167.220.161 – 10.167.220.17410.167.220.175
7610.167.220.176/2810.167.220.177 – 10.167.220.19010.167.220.191
7710.167.220.192/2810.167.220.193 – 10.167.220.20610.167.220.207
7810.167.220.208/2810.167.220.209 – 10.167.220.22210.167.220.223
7910.167.220.224/2810.167.220.225 – 10.167.220.23810.167.220.239
8010.167.220.240/2810.167.220.241 – 10.167.220.25410.167.220.255
8110.167.221.0/2810.167.221.1 – 10.167.221.1410.167.221.15
8210.167.221.16/2810.167.221.17 – 10.167.221.3010.167.221.31
8310.167.221.32/2810.167.221.33 – 10.167.221.4610.167.221.47
8410.167.221.48/2810.167.221.49 – 10.167.221.6210.167.221.63
8510.167.221.64/2810.167.221.65 – 10.167.221.7810.167.221.79
8610.167.221.80/2810.167.221.81 – 10.167.221.9410.167.221.95
8710.167.221.96/2810.167.221.97 – 10.167.221.11010.167.221.111
8810.167.221.112/2810.167.221.113 – 10.167.221.12610.167.221.127
8910.167.221.128/2810.167.221.129 – 10.167.221.14210.167.221.143
9010.167.221.144/2810.167.221.145 – 10.167.221.15810.167.221.159
9110.167.221.160/2810.167.221.161 – 10.167.221.17410.167.221.175
9210.167.221.176/2810.167.221.177 – 10.167.221.19010.167.221.191
9310.167.221.192/2810.167.221.193 – 10.167.221.20610.167.221.207
9410.167.221.208/2810.167.221.209 – 10.167.221.22210.167.221.223
9510.167.221.224/2810.167.221.225 – 10.167.221.23810.167.221.239
9610.167.221.240/2810.167.221.241 – 10.167.221.25410.167.221.255
9710.167.222.0/2810.167.222.1 – 10.167.222.1410.167.222.15
9810.167.222.16/2810.167.222.17 – 10.167.222.3010.167.222.31
9910.167.222.32/2810.167.222.33 – 10.167.222.4610.167.222.47
10010.167.222.48/2810.167.222.49 – 10.167.222.6210.167.222.63
10110.167.222.64/2810.167.222.65 – 10.167.222.7810.167.222.79
10210.167.222.80/2810.167.222.81 – 10.167.222.9410.167.222.95
10310.167.222.96/2810.167.222.97 – 10.167.222.11010.167.222.111
10410.167.222.112/2810.167.222.113 – 10.167.222.12610.167.222.127
10510.167.222.128/2810.167.222.129 – 10.167.222.14210.167.222.143
10610.167.222.144/2810.167.222.145 – 10.167.222.15810.167.222.159
10710.167.222.160/2810.167.222.161 – 10.167.222.17410.167.222.175
10810.167.222.176/2810.167.222.177 – 10.167.222.19010.167.222.191
10910.167.222.192/2810.167.222.193 – 10.167.222.20610.167.222.207
11010.167.222.208/2810.167.222.209 – 10.167.222.22210.167.222.223
11110.167.222.224/2810.167.222.225 – 10.167.222.23810.167.222.239
11210.167.222.240/2810.167.222.241 – 10.167.222.25410.167.222.255
11310.167.223.0/2810.167.223.1 – 10.167.223.1410.167.223.15
11410.167.223.16/2810.167.223.17 – 10.167.223.3010.167.223.31
11510.167.223.32/2810.167.223.33 – 10.167.223.4610.167.223.47
11610.167.223.48/2810.167.223.49 – 10.167.223.6210.167.223.63
11710.167.223.64/2810.167.223.65 – 10.167.223.7810.167.223.79
11810.167.223.80/2810.167.223.81 – 10.167.223.9410.167.223.95
11910.167.223.96/2810.167.223.97 – 10.167.223.11010.167.223.111
12010.167.223.112/2810.167.223.113 – 10.167.223.12610.167.223.127
12110.167.223.128/2810.167.223.129 – 10.167.223.14210.167.223.143
12210.167.223.144/2810.167.223.145 – 10.167.223.15810.167.223.159
12310.167.223.160/2810.167.223.161 – 10.167.223.17410.167.223.175
12410.167.223.176/2810.167.223.177 – 10.167.223.19010.167.223.191
12510.167.223.192/2810.167.223.193 – 10.167.223.20610.167.223.207
12610.167.223.208/2810.167.223.209 – 10.167.223.22210.167.223.223
12710.167.223.224/2810.167.223.225 – 10.167.223.23810.167.223.239
12810.167.223.240/2810.167.223.241 – 10.167.223.25410.167.223.255
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 →