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)10.8.2.16/28

network10.8.2.16/28

broadcast10.8.2.31

first host10.8.2.17

last host10.8.2.30

subnet mask255.255.255.240

wildcard0.0.0.15

addresses16

usable hosts14

classA

ipcalc 10.8.2.16/28

address00001010.00001000.00000010.00010000

subnet mask11111111.11111111.11111111.11110000

network00001010.00001000.00000010.00010000

broadcast00001010.00001000.00000010.00011111

green = network part, grey = host part

hex0x0a080210

decimal168296976

reverse dns16.2.8.10.in-addr.arpa

ipv4-mapped::ffff:a08:210

/28 split into /32 · 16 subnets

close ×

#	network	host range	broadcast
1	10.8.2.16/32	10.8.2.16 – 10.8.2.16	10.8.2.16
2	10.8.2.17/32	10.8.2.17 – 10.8.2.17	10.8.2.17
3	10.8.2.18/32	10.8.2.18 – 10.8.2.18	10.8.2.18
4	10.8.2.19/32	10.8.2.19 – 10.8.2.19	10.8.2.19
5	10.8.2.20/32	10.8.2.20 – 10.8.2.20	10.8.2.20
6	10.8.2.21/32	10.8.2.21 – 10.8.2.21	10.8.2.21
7	10.8.2.22/32	10.8.2.22 – 10.8.2.22	10.8.2.22
8	10.8.2.23/32	10.8.2.23 – 10.8.2.23	10.8.2.23
9	10.8.2.24/32	10.8.2.24 – 10.8.2.24	10.8.2.24
10	10.8.2.25/32	10.8.2.25 – 10.8.2.25	10.8.2.25
11	10.8.2.26/32	10.8.2.26 – 10.8.2.26	10.8.2.26
12	10.8.2.27/32	10.8.2.27 – 10.8.2.27	10.8.2.27
13	10.8.2.28/32	10.8.2.28 – 10.8.2.28	10.8.2.28
14	10.8.2.29/32	10.8.2.29 – 10.8.2.29	10.8.2.29
15	10.8.2.30/32	10.8.2.30 – 10.8.2.30	10.8.2.30
16	10.8.2.31/32	10.8.2.31 – 10.8.2.31	10.8.2.31

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 /28
/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	-
/25	255.255.255.128	128	126	-
/26	255.255.255.192	64	62	-
/27	255.255.255.224	32	30	-
/28	255.255.255.240	16	14	1
/29	255.255.255.248	8	6	2 split →
/30	255.255.255.252	4	2	4 split →
/31	255.255.255.254	2	2	8 split →
/32	255.255.255.255	1	1	16 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 →