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)10.18.167.128/25
network10.18.167.128/25
broadcast10.18.167.255
first host10.18.167.129
last host10.18.167.254
subnet mask255.255.255.128
wildcard0.0.0.127
addresses128
usable hosts126
classA
ipcalc 10.18.167.128/25
address00001010.00010010.10100111.10000000
subnet mask11111111.11111111.11111111.10000000
network00001010.00010010.10100111.10000000
broadcast00001010.00010010.10100111.11111111
green = network part, grey = host part
hex0x0a12a780
decimal168994688
reverse dns128.167.18.10.in-addr.arpa
ipv4-mapped::ffff:a12:a780

/25 split into /30 · 32 subnets

close ×
#networkhost rangebroadcast
110.18.167.128/3010.18.167.129 – 10.18.167.13010.18.167.131
210.18.167.132/3010.18.167.133 – 10.18.167.13410.18.167.135
310.18.167.136/3010.18.167.137 – 10.18.167.13810.18.167.139
410.18.167.140/3010.18.167.141 – 10.18.167.14210.18.167.143
510.18.167.144/3010.18.167.145 – 10.18.167.14610.18.167.147
610.18.167.148/3010.18.167.149 – 10.18.167.15010.18.167.151
710.18.167.152/3010.18.167.153 – 10.18.167.15410.18.167.155
810.18.167.156/3010.18.167.157 – 10.18.167.15810.18.167.159
910.18.167.160/3010.18.167.161 – 10.18.167.16210.18.167.163
1010.18.167.164/3010.18.167.165 – 10.18.167.16610.18.167.167
1110.18.167.168/3010.18.167.169 – 10.18.167.17010.18.167.171
1210.18.167.172/3010.18.167.173 – 10.18.167.17410.18.167.175
1310.18.167.176/3010.18.167.177 – 10.18.167.17810.18.167.179
1410.18.167.180/3010.18.167.181 – 10.18.167.18210.18.167.183
1510.18.167.184/3010.18.167.185 – 10.18.167.18610.18.167.187
1610.18.167.188/3010.18.167.189 – 10.18.167.19010.18.167.191
1710.18.167.192/3010.18.167.193 – 10.18.167.19410.18.167.195
1810.18.167.196/3010.18.167.197 – 10.18.167.19810.18.167.199
1910.18.167.200/3010.18.167.201 – 10.18.167.20210.18.167.203
2010.18.167.204/3010.18.167.205 – 10.18.167.20610.18.167.207
2110.18.167.208/3010.18.167.209 – 10.18.167.21010.18.167.211
2210.18.167.212/3010.18.167.213 – 10.18.167.21410.18.167.215
2310.18.167.216/3010.18.167.217 – 10.18.167.21810.18.167.219
2410.18.167.220/3010.18.167.221 – 10.18.167.22210.18.167.223
2510.18.167.224/3010.18.167.225 – 10.18.167.22610.18.167.227
2610.18.167.228/3010.18.167.229 – 10.18.167.23010.18.167.231
2710.18.167.232/3010.18.167.233 – 10.18.167.23410.18.167.235
2810.18.167.236/3010.18.167.237 – 10.18.167.23810.18.167.239
2910.18.167.240/3010.18.167.241 – 10.18.167.24210.18.167.243
3010.18.167.244/3010.18.167.245 – 10.18.167.24610.18.167.247
3110.18.167.248/3010.18.167.249 – 10.18.167.25010.18.167.251
3210.18.167.252/3010.18.167.253 – 10.18.167.25410.18.167.255
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 →