ip
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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
private IP (RFC 1918)10.2.90.0/23
network10.2.90.0/23
broadcast10.2.91.255
first host10.2.90.1
last host10.2.91.254
subnet mask255.255.254.0
wildcard0.0.1.255
addresses512
usable hosts510
classA
ipcalc 10.2.90.0/23
address00001010.00000010.01011010.00000000
subnet mask11111111.11111111.11111110.00000000
network00001010.00000010.01011010.00000000
broadcast00001010.00000010.01011011.11111111
green = network part, grey = host part
hex0x0a025a00
decimal167926272
reverse dns0.90.2.10.in-addr.arpa
ipv4-mapped::ffff:a02:5a00

/23 split into /28 · 32 subnets

close ×
#networkhost rangebroadcast
110.2.90.0/2810.2.90.1 – 10.2.90.1410.2.90.15
210.2.90.16/2810.2.90.17 – 10.2.90.3010.2.90.31
310.2.90.32/2810.2.90.33 – 10.2.90.4610.2.90.47
410.2.90.48/2810.2.90.49 – 10.2.90.6210.2.90.63
510.2.90.64/2810.2.90.65 – 10.2.90.7810.2.90.79
610.2.90.80/2810.2.90.81 – 10.2.90.9410.2.90.95
710.2.90.96/2810.2.90.97 – 10.2.90.11010.2.90.111
810.2.90.112/2810.2.90.113 – 10.2.90.12610.2.90.127
910.2.90.128/2810.2.90.129 – 10.2.90.14210.2.90.143
1010.2.90.144/2810.2.90.145 – 10.2.90.15810.2.90.159
1110.2.90.160/2810.2.90.161 – 10.2.90.17410.2.90.175
1210.2.90.176/2810.2.90.177 – 10.2.90.19010.2.90.191
1310.2.90.192/2810.2.90.193 – 10.2.90.20610.2.90.207
1410.2.90.208/2810.2.90.209 – 10.2.90.22210.2.90.223
1510.2.90.224/2810.2.90.225 – 10.2.90.23810.2.90.239
1610.2.90.240/2810.2.90.241 – 10.2.90.25410.2.90.255
1710.2.91.0/2810.2.91.1 – 10.2.91.1410.2.91.15
1810.2.91.16/2810.2.91.17 – 10.2.91.3010.2.91.31
1910.2.91.32/2810.2.91.33 – 10.2.91.4610.2.91.47
2010.2.91.48/2810.2.91.49 – 10.2.91.6210.2.91.63
2110.2.91.64/2810.2.91.65 – 10.2.91.7810.2.91.79
2210.2.91.80/2810.2.91.81 – 10.2.91.9410.2.91.95
2310.2.91.96/2810.2.91.97 – 10.2.91.11010.2.91.111
2410.2.91.112/2810.2.91.113 – 10.2.91.12610.2.91.127
2510.2.91.128/2810.2.91.129 – 10.2.91.14210.2.91.143
2610.2.91.144/2810.2.91.145 – 10.2.91.15810.2.91.159
2710.2.91.160/2810.2.91.161 – 10.2.91.17410.2.91.175
2810.2.91.176/2810.2.91.177 – 10.2.91.19010.2.91.191
2910.2.91.192/2810.2.91.193 – 10.2.91.20610.2.91.207
3010.2.91.208/2810.2.91.209 – 10.2.91.22210.2.91.223
3110.2.91.224/2810.2.91.225 – 10.2.91.23810.2.91.239
3210.2.91.240/2810.2.91.241 – 10.2.91.25410.2.91.255
01 / table

IPv4 CIDR prefix table.

Click a prefix longer than your network to split it into subnets.

prefixsubnet maskaddresseshostsin your /23
/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-
/21255.255.248.02,0482,046-
/22255.255.252.01,0241,022-
/23255.255.254.05125101
/24255.255.255.02562542 split →
/25255.255.255.1281281264 split →
/26255.255.255.19264628 split →
/27255.255.255.224323016 split →
/28255.255.255.240161432 split →
/29255.255.255.2488664 split →
/30255.255.255.25242128 split →
/31255.255.255.25422256 split →
/32255.255.255.25511512 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 →