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)10.12.80.0/20
network10.12.80.0/20
broadcast10.12.95.255
first host10.12.80.1
last host10.12.95.254
subnet mask255.255.240.0
wildcard0.0.15.255
addresses4,096
usable hosts4,094
classA
ipcalc 10.12.80.0/20
address00001010.00001100.01010000.00000000
subnet mask11111111.11111111.11110000.00000000
network00001010.00001100.01010000.00000000
broadcast00001010.00001100.01011111.11111111
green = network part, grey = host part
hex0x0a0c5000
decimal168579072
reverse dns0.80.12.10.in-addr.arpa
ipv4-mapped::ffff:a0c:5000

/20 split into /27 · 128 subnets

close ×
#networkhost rangebroadcast
110.12.80.0/2710.12.80.1 – 10.12.80.3010.12.80.31
210.12.80.32/2710.12.80.33 – 10.12.80.6210.12.80.63
310.12.80.64/2710.12.80.65 – 10.12.80.9410.12.80.95
410.12.80.96/2710.12.80.97 – 10.12.80.12610.12.80.127
510.12.80.128/2710.12.80.129 – 10.12.80.15810.12.80.159
610.12.80.160/2710.12.80.161 – 10.12.80.19010.12.80.191
710.12.80.192/2710.12.80.193 – 10.12.80.22210.12.80.223
810.12.80.224/2710.12.80.225 – 10.12.80.25410.12.80.255
910.12.81.0/2710.12.81.1 – 10.12.81.3010.12.81.31
1010.12.81.32/2710.12.81.33 – 10.12.81.6210.12.81.63
1110.12.81.64/2710.12.81.65 – 10.12.81.9410.12.81.95
1210.12.81.96/2710.12.81.97 – 10.12.81.12610.12.81.127
1310.12.81.128/2710.12.81.129 – 10.12.81.15810.12.81.159
1410.12.81.160/2710.12.81.161 – 10.12.81.19010.12.81.191
1510.12.81.192/2710.12.81.193 – 10.12.81.22210.12.81.223
1610.12.81.224/2710.12.81.225 – 10.12.81.25410.12.81.255
1710.12.82.0/2710.12.82.1 – 10.12.82.3010.12.82.31
1810.12.82.32/2710.12.82.33 – 10.12.82.6210.12.82.63
1910.12.82.64/2710.12.82.65 – 10.12.82.9410.12.82.95
2010.12.82.96/2710.12.82.97 – 10.12.82.12610.12.82.127
2110.12.82.128/2710.12.82.129 – 10.12.82.15810.12.82.159
2210.12.82.160/2710.12.82.161 – 10.12.82.19010.12.82.191
2310.12.82.192/2710.12.82.193 – 10.12.82.22210.12.82.223
2410.12.82.224/2710.12.82.225 – 10.12.82.25410.12.82.255
2510.12.83.0/2710.12.83.1 – 10.12.83.3010.12.83.31
2610.12.83.32/2710.12.83.33 – 10.12.83.6210.12.83.63
2710.12.83.64/2710.12.83.65 – 10.12.83.9410.12.83.95
2810.12.83.96/2710.12.83.97 – 10.12.83.12610.12.83.127
2910.12.83.128/2710.12.83.129 – 10.12.83.15810.12.83.159
3010.12.83.160/2710.12.83.161 – 10.12.83.19010.12.83.191
3110.12.83.192/2710.12.83.193 – 10.12.83.22210.12.83.223
3210.12.83.224/2710.12.83.225 – 10.12.83.25410.12.83.255
3310.12.84.0/2710.12.84.1 – 10.12.84.3010.12.84.31
3410.12.84.32/2710.12.84.33 – 10.12.84.6210.12.84.63
3510.12.84.64/2710.12.84.65 – 10.12.84.9410.12.84.95
3610.12.84.96/2710.12.84.97 – 10.12.84.12610.12.84.127
3710.12.84.128/2710.12.84.129 – 10.12.84.15810.12.84.159
3810.12.84.160/2710.12.84.161 – 10.12.84.19010.12.84.191
3910.12.84.192/2710.12.84.193 – 10.12.84.22210.12.84.223
4010.12.84.224/2710.12.84.225 – 10.12.84.25410.12.84.255
4110.12.85.0/2710.12.85.1 – 10.12.85.3010.12.85.31
4210.12.85.32/2710.12.85.33 – 10.12.85.6210.12.85.63
4310.12.85.64/2710.12.85.65 – 10.12.85.9410.12.85.95
4410.12.85.96/2710.12.85.97 – 10.12.85.12610.12.85.127
4510.12.85.128/2710.12.85.129 – 10.12.85.15810.12.85.159
4610.12.85.160/2710.12.85.161 – 10.12.85.19010.12.85.191
4710.12.85.192/2710.12.85.193 – 10.12.85.22210.12.85.223
4810.12.85.224/2710.12.85.225 – 10.12.85.25410.12.85.255
4910.12.86.0/2710.12.86.1 – 10.12.86.3010.12.86.31
5010.12.86.32/2710.12.86.33 – 10.12.86.6210.12.86.63
5110.12.86.64/2710.12.86.65 – 10.12.86.9410.12.86.95
5210.12.86.96/2710.12.86.97 – 10.12.86.12610.12.86.127
5310.12.86.128/2710.12.86.129 – 10.12.86.15810.12.86.159
5410.12.86.160/2710.12.86.161 – 10.12.86.19010.12.86.191
5510.12.86.192/2710.12.86.193 – 10.12.86.22210.12.86.223
5610.12.86.224/2710.12.86.225 – 10.12.86.25410.12.86.255
5710.12.87.0/2710.12.87.1 – 10.12.87.3010.12.87.31
5810.12.87.32/2710.12.87.33 – 10.12.87.6210.12.87.63
5910.12.87.64/2710.12.87.65 – 10.12.87.9410.12.87.95
6010.12.87.96/2710.12.87.97 – 10.12.87.12610.12.87.127
6110.12.87.128/2710.12.87.129 – 10.12.87.15810.12.87.159
6210.12.87.160/2710.12.87.161 – 10.12.87.19010.12.87.191
6310.12.87.192/2710.12.87.193 – 10.12.87.22210.12.87.223
6410.12.87.224/2710.12.87.225 – 10.12.87.25410.12.87.255
6510.12.88.0/2710.12.88.1 – 10.12.88.3010.12.88.31
6610.12.88.32/2710.12.88.33 – 10.12.88.6210.12.88.63
6710.12.88.64/2710.12.88.65 – 10.12.88.9410.12.88.95
6810.12.88.96/2710.12.88.97 – 10.12.88.12610.12.88.127
6910.12.88.128/2710.12.88.129 – 10.12.88.15810.12.88.159
7010.12.88.160/2710.12.88.161 – 10.12.88.19010.12.88.191
7110.12.88.192/2710.12.88.193 – 10.12.88.22210.12.88.223
7210.12.88.224/2710.12.88.225 – 10.12.88.25410.12.88.255
7310.12.89.0/2710.12.89.1 – 10.12.89.3010.12.89.31
7410.12.89.32/2710.12.89.33 – 10.12.89.6210.12.89.63
7510.12.89.64/2710.12.89.65 – 10.12.89.9410.12.89.95
7610.12.89.96/2710.12.89.97 – 10.12.89.12610.12.89.127
7710.12.89.128/2710.12.89.129 – 10.12.89.15810.12.89.159
7810.12.89.160/2710.12.89.161 – 10.12.89.19010.12.89.191
7910.12.89.192/2710.12.89.193 – 10.12.89.22210.12.89.223
8010.12.89.224/2710.12.89.225 – 10.12.89.25410.12.89.255
8110.12.90.0/2710.12.90.1 – 10.12.90.3010.12.90.31
8210.12.90.32/2710.12.90.33 – 10.12.90.6210.12.90.63
8310.12.90.64/2710.12.90.65 – 10.12.90.9410.12.90.95
8410.12.90.96/2710.12.90.97 – 10.12.90.12610.12.90.127
8510.12.90.128/2710.12.90.129 – 10.12.90.15810.12.90.159
8610.12.90.160/2710.12.90.161 – 10.12.90.19010.12.90.191
8710.12.90.192/2710.12.90.193 – 10.12.90.22210.12.90.223
8810.12.90.224/2710.12.90.225 – 10.12.90.25410.12.90.255
8910.12.91.0/2710.12.91.1 – 10.12.91.3010.12.91.31
9010.12.91.32/2710.12.91.33 – 10.12.91.6210.12.91.63
9110.12.91.64/2710.12.91.65 – 10.12.91.9410.12.91.95
9210.12.91.96/2710.12.91.97 – 10.12.91.12610.12.91.127
9310.12.91.128/2710.12.91.129 – 10.12.91.15810.12.91.159
9410.12.91.160/2710.12.91.161 – 10.12.91.19010.12.91.191
9510.12.91.192/2710.12.91.193 – 10.12.91.22210.12.91.223
9610.12.91.224/2710.12.91.225 – 10.12.91.25410.12.91.255
9710.12.92.0/2710.12.92.1 – 10.12.92.3010.12.92.31
9810.12.92.32/2710.12.92.33 – 10.12.92.6210.12.92.63
9910.12.92.64/2710.12.92.65 – 10.12.92.9410.12.92.95
10010.12.92.96/2710.12.92.97 – 10.12.92.12610.12.92.127
10110.12.92.128/2710.12.92.129 – 10.12.92.15810.12.92.159
10210.12.92.160/2710.12.92.161 – 10.12.92.19010.12.92.191
10310.12.92.192/2710.12.92.193 – 10.12.92.22210.12.92.223
10410.12.92.224/2710.12.92.225 – 10.12.92.25410.12.92.255
10510.12.93.0/2710.12.93.1 – 10.12.93.3010.12.93.31
10610.12.93.32/2710.12.93.33 – 10.12.93.6210.12.93.63
10710.12.93.64/2710.12.93.65 – 10.12.93.9410.12.93.95
10810.12.93.96/2710.12.93.97 – 10.12.93.12610.12.93.127
10910.12.93.128/2710.12.93.129 – 10.12.93.15810.12.93.159
11010.12.93.160/2710.12.93.161 – 10.12.93.19010.12.93.191
11110.12.93.192/2710.12.93.193 – 10.12.93.22210.12.93.223
11210.12.93.224/2710.12.93.225 – 10.12.93.25410.12.93.255
11310.12.94.0/2710.12.94.1 – 10.12.94.3010.12.94.31
11410.12.94.32/2710.12.94.33 – 10.12.94.6210.12.94.63
11510.12.94.64/2710.12.94.65 – 10.12.94.9410.12.94.95
11610.12.94.96/2710.12.94.97 – 10.12.94.12610.12.94.127
11710.12.94.128/2710.12.94.129 – 10.12.94.15810.12.94.159
11810.12.94.160/2710.12.94.161 – 10.12.94.19010.12.94.191
11910.12.94.192/2710.12.94.193 – 10.12.94.22210.12.94.223
12010.12.94.224/2710.12.94.225 – 10.12.94.25410.12.94.255
12110.12.95.0/2710.12.95.1 – 10.12.95.3010.12.95.31
12210.12.95.32/2710.12.95.33 – 10.12.95.6210.12.95.63
12310.12.95.64/2710.12.95.65 – 10.12.95.9410.12.95.95
12410.12.95.96/2710.12.95.97 – 10.12.95.12610.12.95.127
12510.12.95.128/2710.12.95.129 – 10.12.95.15810.12.95.159
12610.12.95.160/2710.12.95.161 – 10.12.95.19010.12.95.191
12710.12.95.192/2710.12.95.193 – 10.12.95.22210.12.95.223
12810.12.95.224/2710.12.95.225 – 10.12.95.25410.12.95.255
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 →