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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)10.76.66.0/25
network10.76.66.0/25
broadcast10.76.66.127
first host10.76.66.1
last host10.76.66.126
subnet mask255.255.255.128
wildcard0.0.0.127
addresses128
usable hosts126
classA
ipcalc 10.76.66.0/25
address00001010.01001100.01000010.00000000
subnet mask11111111.11111111.11111111.10000000
network00001010.01001100.01000010.00000000
broadcast00001010.01001100.01000010.01111111
green = network part, grey = host part
hex0x0a4c4200
decimal172769792
reverse dns0.66.76.10.in-addr.arpa
ipv4-mapped::ffff:a4c:4200

/25 split into /30 · 32 subnets

close ×
#networkhost rangebroadcast
110.76.66.0/3010.76.66.1 – 10.76.66.210.76.66.3
210.76.66.4/3010.76.66.5 – 10.76.66.610.76.66.7
310.76.66.8/3010.76.66.9 – 10.76.66.1010.76.66.11
410.76.66.12/3010.76.66.13 – 10.76.66.1410.76.66.15
510.76.66.16/3010.76.66.17 – 10.76.66.1810.76.66.19
610.76.66.20/3010.76.66.21 – 10.76.66.2210.76.66.23
710.76.66.24/3010.76.66.25 – 10.76.66.2610.76.66.27
810.76.66.28/3010.76.66.29 – 10.76.66.3010.76.66.31
910.76.66.32/3010.76.66.33 – 10.76.66.3410.76.66.35
1010.76.66.36/3010.76.66.37 – 10.76.66.3810.76.66.39
1110.76.66.40/3010.76.66.41 – 10.76.66.4210.76.66.43
1210.76.66.44/3010.76.66.45 – 10.76.66.4610.76.66.47
1310.76.66.48/3010.76.66.49 – 10.76.66.5010.76.66.51
1410.76.66.52/3010.76.66.53 – 10.76.66.5410.76.66.55
1510.76.66.56/3010.76.66.57 – 10.76.66.5810.76.66.59
1610.76.66.60/3010.76.66.61 – 10.76.66.6210.76.66.63
1710.76.66.64/3010.76.66.65 – 10.76.66.6610.76.66.67
1810.76.66.68/3010.76.66.69 – 10.76.66.7010.76.66.71
1910.76.66.72/3010.76.66.73 – 10.76.66.7410.76.66.75
2010.76.66.76/3010.76.66.77 – 10.76.66.7810.76.66.79
2110.76.66.80/3010.76.66.81 – 10.76.66.8210.76.66.83
2210.76.66.84/3010.76.66.85 – 10.76.66.8610.76.66.87
2310.76.66.88/3010.76.66.89 – 10.76.66.9010.76.66.91
2410.76.66.92/3010.76.66.93 – 10.76.66.9410.76.66.95
2510.76.66.96/3010.76.66.97 – 10.76.66.9810.76.66.99
2610.76.66.100/3010.76.66.101 – 10.76.66.10210.76.66.103
2710.76.66.104/3010.76.66.105 – 10.76.66.10610.76.66.107
2810.76.66.108/3010.76.66.109 – 10.76.66.11010.76.66.111
2910.76.66.112/3010.76.66.113 – 10.76.66.11410.76.66.115
3010.76.66.116/3010.76.66.117 – 10.76.66.11810.76.66.119
3110.76.66.120/3010.76.66.121 – 10.76.66.12210.76.66.123
3210.76.66.124/3010.76.66.125 – 10.76.66.12610.76.66.127
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 →