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)10.232.20.0/25
network10.232.20.0/25
broadcast10.232.20.127
first host10.232.20.1
last host10.232.20.126
subnet mask255.255.255.128
wildcard0.0.0.127
addresses128
usable hosts126
classA
ipcalc 10.232.20.0/25
address00001010.11101000.00010100.00000000
subnet mask11111111.11111111.11111111.10000000
network00001010.11101000.00010100.00000000
broadcast00001010.11101000.00010100.01111111
green = network part, grey = host part
hex0x0ae81400
decimal182981632
reverse dns0.20.232.10.in-addr.arpa
ipv4-mapped::ffff:ae8:1400

/25 split into /30 · 32 subnets

close ×
#networkhost rangebroadcast
110.232.20.0/3010.232.20.1 – 10.232.20.210.232.20.3
210.232.20.4/3010.232.20.5 – 10.232.20.610.232.20.7
310.232.20.8/3010.232.20.9 – 10.232.20.1010.232.20.11
410.232.20.12/3010.232.20.13 – 10.232.20.1410.232.20.15
510.232.20.16/3010.232.20.17 – 10.232.20.1810.232.20.19
610.232.20.20/3010.232.20.21 – 10.232.20.2210.232.20.23
710.232.20.24/3010.232.20.25 – 10.232.20.2610.232.20.27
810.232.20.28/3010.232.20.29 – 10.232.20.3010.232.20.31
910.232.20.32/3010.232.20.33 – 10.232.20.3410.232.20.35
1010.232.20.36/3010.232.20.37 – 10.232.20.3810.232.20.39
1110.232.20.40/3010.232.20.41 – 10.232.20.4210.232.20.43
1210.232.20.44/3010.232.20.45 – 10.232.20.4610.232.20.47
1310.232.20.48/3010.232.20.49 – 10.232.20.5010.232.20.51
1410.232.20.52/3010.232.20.53 – 10.232.20.5410.232.20.55
1510.232.20.56/3010.232.20.57 – 10.232.20.5810.232.20.59
1610.232.20.60/3010.232.20.61 – 10.232.20.6210.232.20.63
1710.232.20.64/3010.232.20.65 – 10.232.20.6610.232.20.67
1810.232.20.68/3010.232.20.69 – 10.232.20.7010.232.20.71
1910.232.20.72/3010.232.20.73 – 10.232.20.7410.232.20.75
2010.232.20.76/3010.232.20.77 – 10.232.20.7810.232.20.79
2110.232.20.80/3010.232.20.81 – 10.232.20.8210.232.20.83
2210.232.20.84/3010.232.20.85 – 10.232.20.8610.232.20.87
2310.232.20.88/3010.232.20.89 – 10.232.20.9010.232.20.91
2410.232.20.92/3010.232.20.93 – 10.232.20.9410.232.20.95
2510.232.20.96/3010.232.20.97 – 10.232.20.9810.232.20.99
2610.232.20.100/3010.232.20.101 – 10.232.20.10210.232.20.103
2710.232.20.104/3010.232.20.105 – 10.232.20.10610.232.20.107
2810.232.20.108/3010.232.20.109 – 10.232.20.11010.232.20.111
2910.232.20.112/3010.232.20.113 – 10.232.20.11410.232.20.115
3010.232.20.116/3010.232.20.117 – 10.232.20.11810.232.20.119
3110.232.20.120/3010.232.20.121 – 10.232.20.12210.232.20.123
3210.232.20.124/3010.232.20.125 – 10.232.20.12610.232.20.127
01 / table

IPv4 CIDR prefix table.

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

prefixsubnet maskaddresseshostsin your /25
/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-
/23255.255.254.0512510-
/24255.255.255.0256254-
/25255.255.255.1281281261
/26255.255.255.19264622 split →
/27255.255.255.22432304 split →
/28255.255.255.24016148 split →
/29255.255.255.2488616 split →
/30255.255.255.2524232 split →
/31255.255.255.2542264 split →
/32255.255.255.25511128 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 →