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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)10.166.80.0/20
network10.166.80.0/20
broadcast10.166.95.255
first host10.166.80.1
last host10.166.95.254
subnet mask255.255.240.0
wildcard0.0.15.255
addresses4,096
usable hosts4,094
classA
ipcalc 10.166.80.0/20
address00001010.10100110.01010000.00000000
subnet mask11111111.11111111.11110000.00000000
network00001010.10100110.01010000.00000000
broadcast00001010.10100110.01011111.11111111
green = network part, grey = host part
hex0x0aa65000
decimal178671616
reverse dns0.80.166.10.in-addr.arpa
ipv4-mapped::ffff:aa6:5000

/20 split into /26 · 64 subnets

close ×
#networkhost rangebroadcast
110.166.80.0/2610.166.80.1 – 10.166.80.6210.166.80.63
210.166.80.64/2610.166.80.65 – 10.166.80.12610.166.80.127
310.166.80.128/2610.166.80.129 – 10.166.80.19010.166.80.191
410.166.80.192/2610.166.80.193 – 10.166.80.25410.166.80.255
510.166.81.0/2610.166.81.1 – 10.166.81.6210.166.81.63
610.166.81.64/2610.166.81.65 – 10.166.81.12610.166.81.127
710.166.81.128/2610.166.81.129 – 10.166.81.19010.166.81.191
810.166.81.192/2610.166.81.193 – 10.166.81.25410.166.81.255
910.166.82.0/2610.166.82.1 – 10.166.82.6210.166.82.63
1010.166.82.64/2610.166.82.65 – 10.166.82.12610.166.82.127
1110.166.82.128/2610.166.82.129 – 10.166.82.19010.166.82.191
1210.166.82.192/2610.166.82.193 – 10.166.82.25410.166.82.255
1310.166.83.0/2610.166.83.1 – 10.166.83.6210.166.83.63
1410.166.83.64/2610.166.83.65 – 10.166.83.12610.166.83.127
1510.166.83.128/2610.166.83.129 – 10.166.83.19010.166.83.191
1610.166.83.192/2610.166.83.193 – 10.166.83.25410.166.83.255
1710.166.84.0/2610.166.84.1 – 10.166.84.6210.166.84.63
1810.166.84.64/2610.166.84.65 – 10.166.84.12610.166.84.127
1910.166.84.128/2610.166.84.129 – 10.166.84.19010.166.84.191
2010.166.84.192/2610.166.84.193 – 10.166.84.25410.166.84.255
2110.166.85.0/2610.166.85.1 – 10.166.85.6210.166.85.63
2210.166.85.64/2610.166.85.65 – 10.166.85.12610.166.85.127
2310.166.85.128/2610.166.85.129 – 10.166.85.19010.166.85.191
2410.166.85.192/2610.166.85.193 – 10.166.85.25410.166.85.255
2510.166.86.0/2610.166.86.1 – 10.166.86.6210.166.86.63
2610.166.86.64/2610.166.86.65 – 10.166.86.12610.166.86.127
2710.166.86.128/2610.166.86.129 – 10.166.86.19010.166.86.191
2810.166.86.192/2610.166.86.193 – 10.166.86.25410.166.86.255
2910.166.87.0/2610.166.87.1 – 10.166.87.6210.166.87.63
3010.166.87.64/2610.166.87.65 – 10.166.87.12610.166.87.127
3110.166.87.128/2610.166.87.129 – 10.166.87.19010.166.87.191
3210.166.87.192/2610.166.87.193 – 10.166.87.25410.166.87.255
3310.166.88.0/2610.166.88.1 – 10.166.88.6210.166.88.63
3410.166.88.64/2610.166.88.65 – 10.166.88.12610.166.88.127
3510.166.88.128/2610.166.88.129 – 10.166.88.19010.166.88.191
3610.166.88.192/2610.166.88.193 – 10.166.88.25410.166.88.255
3710.166.89.0/2610.166.89.1 – 10.166.89.6210.166.89.63
3810.166.89.64/2610.166.89.65 – 10.166.89.12610.166.89.127
3910.166.89.128/2610.166.89.129 – 10.166.89.19010.166.89.191
4010.166.89.192/2610.166.89.193 – 10.166.89.25410.166.89.255
4110.166.90.0/2610.166.90.1 – 10.166.90.6210.166.90.63
4210.166.90.64/2610.166.90.65 – 10.166.90.12610.166.90.127
4310.166.90.128/2610.166.90.129 – 10.166.90.19010.166.90.191
4410.166.90.192/2610.166.90.193 – 10.166.90.25410.166.90.255
4510.166.91.0/2610.166.91.1 – 10.166.91.6210.166.91.63
4610.166.91.64/2610.166.91.65 – 10.166.91.12610.166.91.127
4710.166.91.128/2610.166.91.129 – 10.166.91.19010.166.91.191
4810.166.91.192/2610.166.91.193 – 10.166.91.25410.166.91.255
4910.166.92.0/2610.166.92.1 – 10.166.92.6210.166.92.63
5010.166.92.64/2610.166.92.65 – 10.166.92.12610.166.92.127
5110.166.92.128/2610.166.92.129 – 10.166.92.19010.166.92.191
5210.166.92.192/2610.166.92.193 – 10.166.92.25410.166.92.255
5310.166.93.0/2610.166.93.1 – 10.166.93.6210.166.93.63
5410.166.93.64/2610.166.93.65 – 10.166.93.12610.166.93.127
5510.166.93.128/2610.166.93.129 – 10.166.93.19010.166.93.191
5610.166.93.192/2610.166.93.193 – 10.166.93.25410.166.93.255
5710.166.94.0/2610.166.94.1 – 10.166.94.6210.166.94.63
5810.166.94.64/2610.166.94.65 – 10.166.94.12610.166.94.127
5910.166.94.128/2610.166.94.129 – 10.166.94.19010.166.94.191
6010.166.94.192/2610.166.94.193 – 10.166.94.25410.166.94.255
6110.166.95.0/2610.166.95.1 – 10.166.95.6210.166.95.63
6210.166.95.64/2610.166.95.65 – 10.166.95.12610.166.95.127
6310.166.95.128/2610.166.95.129 – 10.166.95.19010.166.95.191
6410.166.95.192/2610.166.95.193 – 10.166.95.25410.166.95.255
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 →