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.

Try:192.168.1.10/24 10.0.0.0/8 172.16.5.4/20 203.0.113.9/29

IPv6 calculator →

private IP (RFC 1918)10.2.8.0/24

network10.2.8.0/24

broadcast10.2.8.255

first host10.2.8.1

last host10.2.8.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.2.8.0/24

address00001010.00000010.00001000.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.00000010.00001000.00000000

broadcast00001010.00000010.00001000.11111111

green = network part, grey = host part

hex0x0a020800

decimal167905280

reverse dns0.8.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:800

/24 split into /29 · 32 subnets

close ×

#	network	host range	broadcast
1	10.2.8.0/29	10.2.8.1 – 10.2.8.6	10.2.8.7
2	10.2.8.8/29	10.2.8.9 – 10.2.8.14	10.2.8.15
3	10.2.8.16/29	10.2.8.17 – 10.2.8.22	10.2.8.23
4	10.2.8.24/29	10.2.8.25 – 10.2.8.30	10.2.8.31
5	10.2.8.32/29	10.2.8.33 – 10.2.8.38	10.2.8.39
6	10.2.8.40/29	10.2.8.41 – 10.2.8.46	10.2.8.47
7	10.2.8.48/29	10.2.8.49 – 10.2.8.54	10.2.8.55
8	10.2.8.56/29	10.2.8.57 – 10.2.8.62	10.2.8.63
9	10.2.8.64/29	10.2.8.65 – 10.2.8.70	10.2.8.71
10	10.2.8.72/29	10.2.8.73 – 10.2.8.78	10.2.8.79
11	10.2.8.80/29	10.2.8.81 – 10.2.8.86	10.2.8.87
12	10.2.8.88/29	10.2.8.89 – 10.2.8.94	10.2.8.95
13	10.2.8.96/29	10.2.8.97 – 10.2.8.102	10.2.8.103
14	10.2.8.104/29	10.2.8.105 – 10.2.8.110	10.2.8.111
15	10.2.8.112/29	10.2.8.113 – 10.2.8.118	10.2.8.119
16	10.2.8.120/29	10.2.8.121 – 10.2.8.126	10.2.8.127
17	10.2.8.128/29	10.2.8.129 – 10.2.8.134	10.2.8.135
18	10.2.8.136/29	10.2.8.137 – 10.2.8.142	10.2.8.143
19	10.2.8.144/29	10.2.8.145 – 10.2.8.150	10.2.8.151
20	10.2.8.152/29	10.2.8.153 – 10.2.8.158	10.2.8.159
21	10.2.8.160/29	10.2.8.161 – 10.2.8.166	10.2.8.167
22	10.2.8.168/29	10.2.8.169 – 10.2.8.174	10.2.8.175
23	10.2.8.176/29	10.2.8.177 – 10.2.8.182	10.2.8.183
24	10.2.8.184/29	10.2.8.185 – 10.2.8.190	10.2.8.191
25	10.2.8.192/29	10.2.8.193 – 10.2.8.198	10.2.8.199
26	10.2.8.200/29	10.2.8.201 – 10.2.8.206	10.2.8.207
27	10.2.8.208/29	10.2.8.209 – 10.2.8.214	10.2.8.215
28	10.2.8.216/29	10.2.8.217 – 10.2.8.222	10.2.8.223
29	10.2.8.224/29	10.2.8.225 – 10.2.8.230	10.2.8.231
30	10.2.8.232/29	10.2.8.233 – 10.2.8.238	10.2.8.239
31	10.2.8.240/29	10.2.8.241 – 10.2.8.246	10.2.8.247
32	10.2.8.248/29	10.2.8.249 – 10.2.8.254	10.2.8.255

01 / table

IPv4 CIDR prefix table.

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

prefix	subnet mask	addresses	hosts	in your /24
/0	0.0.0.0	4,294,967,296	4,294,967,294	-
/1	128.0.0.0	2,147,483,648	2,147,483,646	-
/2	192.0.0.0	1,073,741,824	1,073,741,822	-
/3	224.0.0.0	536,870,912	536,870,910	-
/4	240.0.0.0	268,435,456	268,435,454	-
/5	248.0.0.0	134,217,728	134,217,726	-
/6	252.0.0.0	67,108,864	67,108,862	-
/7	254.0.0.0	33,554,432	33,554,430	-
/8	255.0.0.0	16,777,216	16,777,214	-
/9	255.128.0.0	8,388,608	8,388,606	-
/10	255.192.0.0	4,194,304	4,194,302	-
/11	255.224.0.0	2,097,152	2,097,150	-
/12	255.240.0.0	1,048,576	1,048,574	-
/13	255.248.0.0	524,288	524,286	-
/14	255.252.0.0	262,144	262,142	-
/15	255.254.0.0	131,072	131,070	-
/16	255.255.0.0	65,536	65,534	-
/17	255.255.128.0	32,768	32,766	-
/18	255.255.192.0	16,384	16,382	-
/19	255.255.224.0	8,192	8,190	-
/20	255.255.240.0	4,096	4,094	-
/21	255.255.248.0	2,048	2,046	-
/22	255.255.252.0	1,024	1,022	-
/23	255.255.254.0	512	510	-
/24	255.255.255.0	256	254	1
/25	255.255.255.128	128	126	2 split →
/26	255.255.255.192	64	62	4 split →
/27	255.255.255.224	32	30	8 split →
/28	255.255.255.240	16	14	16 split →
/29	255.255.255.248	8	6	32 split →
/30	255.255.255.252	4	2	64 split →
/31	255.255.255.254	2	2	128 split →
/32	255.255.255.255	1	1	256 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 →