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)10.2.48.0/21
network10.2.48.0/21
broadcast10.2.55.255
first host10.2.48.1
last host10.2.55.254
subnet mask255.255.248.0
wildcard0.0.7.255
addresses2,048
usable hosts2,046
classA
ipcalc 10.2.48.0/21
address00001010.00000010.00110000.00000000
subnet mask11111111.11111111.11111000.00000000
network00001010.00000010.00110000.00000000
broadcast00001010.00000010.00110111.11111111
green = network part, grey = host part
hex0x0a023000
decimal167915520
reverse dns0.48.2.10.in-addr.arpa
ipv4-mapped::ffff:a02:3000

/21 split into /28 · 128 subnets

close ×
#networkhost rangebroadcast
110.2.48.0/2810.2.48.1 – 10.2.48.1410.2.48.15
210.2.48.16/2810.2.48.17 – 10.2.48.3010.2.48.31
310.2.48.32/2810.2.48.33 – 10.2.48.4610.2.48.47
410.2.48.48/2810.2.48.49 – 10.2.48.6210.2.48.63
510.2.48.64/2810.2.48.65 – 10.2.48.7810.2.48.79
610.2.48.80/2810.2.48.81 – 10.2.48.9410.2.48.95
710.2.48.96/2810.2.48.97 – 10.2.48.11010.2.48.111
810.2.48.112/2810.2.48.113 – 10.2.48.12610.2.48.127
910.2.48.128/2810.2.48.129 – 10.2.48.14210.2.48.143
1010.2.48.144/2810.2.48.145 – 10.2.48.15810.2.48.159
1110.2.48.160/2810.2.48.161 – 10.2.48.17410.2.48.175
1210.2.48.176/2810.2.48.177 – 10.2.48.19010.2.48.191
1310.2.48.192/2810.2.48.193 – 10.2.48.20610.2.48.207
1410.2.48.208/2810.2.48.209 – 10.2.48.22210.2.48.223
1510.2.48.224/2810.2.48.225 – 10.2.48.23810.2.48.239
1610.2.48.240/2810.2.48.241 – 10.2.48.25410.2.48.255
1710.2.49.0/2810.2.49.1 – 10.2.49.1410.2.49.15
1810.2.49.16/2810.2.49.17 – 10.2.49.3010.2.49.31
1910.2.49.32/2810.2.49.33 – 10.2.49.4610.2.49.47
2010.2.49.48/2810.2.49.49 – 10.2.49.6210.2.49.63
2110.2.49.64/2810.2.49.65 – 10.2.49.7810.2.49.79
2210.2.49.80/2810.2.49.81 – 10.2.49.9410.2.49.95
2310.2.49.96/2810.2.49.97 – 10.2.49.11010.2.49.111
2410.2.49.112/2810.2.49.113 – 10.2.49.12610.2.49.127
2510.2.49.128/2810.2.49.129 – 10.2.49.14210.2.49.143
2610.2.49.144/2810.2.49.145 – 10.2.49.15810.2.49.159
2710.2.49.160/2810.2.49.161 – 10.2.49.17410.2.49.175
2810.2.49.176/2810.2.49.177 – 10.2.49.19010.2.49.191
2910.2.49.192/2810.2.49.193 – 10.2.49.20610.2.49.207
3010.2.49.208/2810.2.49.209 – 10.2.49.22210.2.49.223
3110.2.49.224/2810.2.49.225 – 10.2.49.23810.2.49.239
3210.2.49.240/2810.2.49.241 – 10.2.49.25410.2.49.255
3310.2.50.0/2810.2.50.1 – 10.2.50.1410.2.50.15
3410.2.50.16/2810.2.50.17 – 10.2.50.3010.2.50.31
3510.2.50.32/2810.2.50.33 – 10.2.50.4610.2.50.47
3610.2.50.48/2810.2.50.49 – 10.2.50.6210.2.50.63
3710.2.50.64/2810.2.50.65 – 10.2.50.7810.2.50.79
3810.2.50.80/2810.2.50.81 – 10.2.50.9410.2.50.95
3910.2.50.96/2810.2.50.97 – 10.2.50.11010.2.50.111
4010.2.50.112/2810.2.50.113 – 10.2.50.12610.2.50.127
4110.2.50.128/2810.2.50.129 – 10.2.50.14210.2.50.143
4210.2.50.144/2810.2.50.145 – 10.2.50.15810.2.50.159
4310.2.50.160/2810.2.50.161 – 10.2.50.17410.2.50.175
4410.2.50.176/2810.2.50.177 – 10.2.50.19010.2.50.191
4510.2.50.192/2810.2.50.193 – 10.2.50.20610.2.50.207
4610.2.50.208/2810.2.50.209 – 10.2.50.22210.2.50.223
4710.2.50.224/2810.2.50.225 – 10.2.50.23810.2.50.239
4810.2.50.240/2810.2.50.241 – 10.2.50.25410.2.50.255
4910.2.51.0/2810.2.51.1 – 10.2.51.1410.2.51.15
5010.2.51.16/2810.2.51.17 – 10.2.51.3010.2.51.31
5110.2.51.32/2810.2.51.33 – 10.2.51.4610.2.51.47
5210.2.51.48/2810.2.51.49 – 10.2.51.6210.2.51.63
5310.2.51.64/2810.2.51.65 – 10.2.51.7810.2.51.79
5410.2.51.80/2810.2.51.81 – 10.2.51.9410.2.51.95
5510.2.51.96/2810.2.51.97 – 10.2.51.11010.2.51.111
5610.2.51.112/2810.2.51.113 – 10.2.51.12610.2.51.127
5710.2.51.128/2810.2.51.129 – 10.2.51.14210.2.51.143
5810.2.51.144/2810.2.51.145 – 10.2.51.15810.2.51.159
5910.2.51.160/2810.2.51.161 – 10.2.51.17410.2.51.175
6010.2.51.176/2810.2.51.177 – 10.2.51.19010.2.51.191
6110.2.51.192/2810.2.51.193 – 10.2.51.20610.2.51.207
6210.2.51.208/2810.2.51.209 – 10.2.51.22210.2.51.223
6310.2.51.224/2810.2.51.225 – 10.2.51.23810.2.51.239
6410.2.51.240/2810.2.51.241 – 10.2.51.25410.2.51.255
6510.2.52.0/2810.2.52.1 – 10.2.52.1410.2.52.15
6610.2.52.16/2810.2.52.17 – 10.2.52.3010.2.52.31
6710.2.52.32/2810.2.52.33 – 10.2.52.4610.2.52.47
6810.2.52.48/2810.2.52.49 – 10.2.52.6210.2.52.63
6910.2.52.64/2810.2.52.65 – 10.2.52.7810.2.52.79
7010.2.52.80/2810.2.52.81 – 10.2.52.9410.2.52.95
7110.2.52.96/2810.2.52.97 – 10.2.52.11010.2.52.111
7210.2.52.112/2810.2.52.113 – 10.2.52.12610.2.52.127
7310.2.52.128/2810.2.52.129 – 10.2.52.14210.2.52.143
7410.2.52.144/2810.2.52.145 – 10.2.52.15810.2.52.159
7510.2.52.160/2810.2.52.161 – 10.2.52.17410.2.52.175
7610.2.52.176/2810.2.52.177 – 10.2.52.19010.2.52.191
7710.2.52.192/2810.2.52.193 – 10.2.52.20610.2.52.207
7810.2.52.208/2810.2.52.209 – 10.2.52.22210.2.52.223
7910.2.52.224/2810.2.52.225 – 10.2.52.23810.2.52.239
8010.2.52.240/2810.2.52.241 – 10.2.52.25410.2.52.255
8110.2.53.0/2810.2.53.1 – 10.2.53.1410.2.53.15
8210.2.53.16/2810.2.53.17 – 10.2.53.3010.2.53.31
8310.2.53.32/2810.2.53.33 – 10.2.53.4610.2.53.47
8410.2.53.48/2810.2.53.49 – 10.2.53.6210.2.53.63
8510.2.53.64/2810.2.53.65 – 10.2.53.7810.2.53.79
8610.2.53.80/2810.2.53.81 – 10.2.53.9410.2.53.95
8710.2.53.96/2810.2.53.97 – 10.2.53.11010.2.53.111
8810.2.53.112/2810.2.53.113 – 10.2.53.12610.2.53.127
8910.2.53.128/2810.2.53.129 – 10.2.53.14210.2.53.143
9010.2.53.144/2810.2.53.145 – 10.2.53.15810.2.53.159
9110.2.53.160/2810.2.53.161 – 10.2.53.17410.2.53.175
9210.2.53.176/2810.2.53.177 – 10.2.53.19010.2.53.191
9310.2.53.192/2810.2.53.193 – 10.2.53.20610.2.53.207
9410.2.53.208/2810.2.53.209 – 10.2.53.22210.2.53.223
9510.2.53.224/2810.2.53.225 – 10.2.53.23810.2.53.239
9610.2.53.240/2810.2.53.241 – 10.2.53.25410.2.53.255
9710.2.54.0/2810.2.54.1 – 10.2.54.1410.2.54.15
9810.2.54.16/2810.2.54.17 – 10.2.54.3010.2.54.31
9910.2.54.32/2810.2.54.33 – 10.2.54.4610.2.54.47
10010.2.54.48/2810.2.54.49 – 10.2.54.6210.2.54.63
10110.2.54.64/2810.2.54.65 – 10.2.54.7810.2.54.79
10210.2.54.80/2810.2.54.81 – 10.2.54.9410.2.54.95
10310.2.54.96/2810.2.54.97 – 10.2.54.11010.2.54.111
10410.2.54.112/2810.2.54.113 – 10.2.54.12610.2.54.127
10510.2.54.128/2810.2.54.129 – 10.2.54.14210.2.54.143
10610.2.54.144/2810.2.54.145 – 10.2.54.15810.2.54.159
10710.2.54.160/2810.2.54.161 – 10.2.54.17410.2.54.175
10810.2.54.176/2810.2.54.177 – 10.2.54.19010.2.54.191
10910.2.54.192/2810.2.54.193 – 10.2.54.20610.2.54.207
11010.2.54.208/2810.2.54.209 – 10.2.54.22210.2.54.223
11110.2.54.224/2810.2.54.225 – 10.2.54.23810.2.54.239
11210.2.54.240/2810.2.54.241 – 10.2.54.25410.2.54.255
11310.2.55.0/2810.2.55.1 – 10.2.55.1410.2.55.15
11410.2.55.16/2810.2.55.17 – 10.2.55.3010.2.55.31
11510.2.55.32/2810.2.55.33 – 10.2.55.4610.2.55.47
11610.2.55.48/2810.2.55.49 – 10.2.55.6210.2.55.63
11710.2.55.64/2810.2.55.65 – 10.2.55.7810.2.55.79
11810.2.55.80/2810.2.55.81 – 10.2.55.9410.2.55.95
11910.2.55.96/2810.2.55.97 – 10.2.55.11010.2.55.111
12010.2.55.112/2810.2.55.113 – 10.2.55.12610.2.55.127
12110.2.55.128/2810.2.55.129 – 10.2.55.14210.2.55.143
12210.2.55.144/2810.2.55.145 – 10.2.55.15810.2.55.159
12310.2.55.160/2810.2.55.161 – 10.2.55.17410.2.55.175
12410.2.55.176/2810.2.55.177 – 10.2.55.19010.2.55.191
12510.2.55.192/2810.2.55.193 – 10.2.55.20610.2.55.207
12610.2.55.208/2810.2.55.209 – 10.2.55.22210.2.55.223
12710.2.55.224/2810.2.55.225 – 10.2.55.23810.2.55.239
12810.2.55.240/2810.2.55.241 – 10.2.55.25410.2.55.255
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 →