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)10.15.96.0/20

network10.15.96.0/20

broadcast10.15.111.255

first host10.15.96.1

last host10.15.111.254

subnet mask255.255.240.0

wildcard0.0.15.255

addresses4,096

usable hosts4,094

classA

ipcalc 10.15.96.0/20

address00001010.00001111.01100000.00000000

subnet mask11111111.11111111.11110000.00000000

network00001010.00001111.01100000.00000000

broadcast00001010.00001111.01101111.11111111

green = network part, grey = host part

hex0x0a0f6000

decimal168779776

reverse dns0.96.15.10.in-addr.arpa

ipv4-mapped::ffff:a0f:6000

/20 split into /26 · 64 subnets

close ×

#	network	host range	broadcast
1	10.15.96.0/26	10.15.96.1 – 10.15.96.62	10.15.96.63
2	10.15.96.64/26	10.15.96.65 – 10.15.96.126	10.15.96.127
3	10.15.96.128/26	10.15.96.129 – 10.15.96.190	10.15.96.191
4	10.15.96.192/26	10.15.96.193 – 10.15.96.254	10.15.96.255
5	10.15.97.0/26	10.15.97.1 – 10.15.97.62	10.15.97.63
6	10.15.97.64/26	10.15.97.65 – 10.15.97.126	10.15.97.127
7	10.15.97.128/26	10.15.97.129 – 10.15.97.190	10.15.97.191
8	10.15.97.192/26	10.15.97.193 – 10.15.97.254	10.15.97.255
9	10.15.98.0/26	10.15.98.1 – 10.15.98.62	10.15.98.63
10	10.15.98.64/26	10.15.98.65 – 10.15.98.126	10.15.98.127
11	10.15.98.128/26	10.15.98.129 – 10.15.98.190	10.15.98.191
12	10.15.98.192/26	10.15.98.193 – 10.15.98.254	10.15.98.255
13	10.15.99.0/26	10.15.99.1 – 10.15.99.62	10.15.99.63
14	10.15.99.64/26	10.15.99.65 – 10.15.99.126	10.15.99.127
15	10.15.99.128/26	10.15.99.129 – 10.15.99.190	10.15.99.191
16	10.15.99.192/26	10.15.99.193 – 10.15.99.254	10.15.99.255
17	10.15.100.0/26	10.15.100.1 – 10.15.100.62	10.15.100.63
18	10.15.100.64/26	10.15.100.65 – 10.15.100.126	10.15.100.127
19	10.15.100.128/26	10.15.100.129 – 10.15.100.190	10.15.100.191
20	10.15.100.192/26	10.15.100.193 – 10.15.100.254	10.15.100.255
21	10.15.101.0/26	10.15.101.1 – 10.15.101.62	10.15.101.63
22	10.15.101.64/26	10.15.101.65 – 10.15.101.126	10.15.101.127
23	10.15.101.128/26	10.15.101.129 – 10.15.101.190	10.15.101.191
24	10.15.101.192/26	10.15.101.193 – 10.15.101.254	10.15.101.255
25	10.15.102.0/26	10.15.102.1 – 10.15.102.62	10.15.102.63
26	10.15.102.64/26	10.15.102.65 – 10.15.102.126	10.15.102.127
27	10.15.102.128/26	10.15.102.129 – 10.15.102.190	10.15.102.191
28	10.15.102.192/26	10.15.102.193 – 10.15.102.254	10.15.102.255
29	10.15.103.0/26	10.15.103.1 – 10.15.103.62	10.15.103.63
30	10.15.103.64/26	10.15.103.65 – 10.15.103.126	10.15.103.127
31	10.15.103.128/26	10.15.103.129 – 10.15.103.190	10.15.103.191
32	10.15.103.192/26	10.15.103.193 – 10.15.103.254	10.15.103.255
33	10.15.104.0/26	10.15.104.1 – 10.15.104.62	10.15.104.63
34	10.15.104.64/26	10.15.104.65 – 10.15.104.126	10.15.104.127
35	10.15.104.128/26	10.15.104.129 – 10.15.104.190	10.15.104.191
36	10.15.104.192/26	10.15.104.193 – 10.15.104.254	10.15.104.255
37	10.15.105.0/26	10.15.105.1 – 10.15.105.62	10.15.105.63
38	10.15.105.64/26	10.15.105.65 – 10.15.105.126	10.15.105.127
39	10.15.105.128/26	10.15.105.129 – 10.15.105.190	10.15.105.191
40	10.15.105.192/26	10.15.105.193 – 10.15.105.254	10.15.105.255
41	10.15.106.0/26	10.15.106.1 – 10.15.106.62	10.15.106.63
42	10.15.106.64/26	10.15.106.65 – 10.15.106.126	10.15.106.127
43	10.15.106.128/26	10.15.106.129 – 10.15.106.190	10.15.106.191
44	10.15.106.192/26	10.15.106.193 – 10.15.106.254	10.15.106.255
45	10.15.107.0/26	10.15.107.1 – 10.15.107.62	10.15.107.63
46	10.15.107.64/26	10.15.107.65 – 10.15.107.126	10.15.107.127
47	10.15.107.128/26	10.15.107.129 – 10.15.107.190	10.15.107.191
48	10.15.107.192/26	10.15.107.193 – 10.15.107.254	10.15.107.255
49	10.15.108.0/26	10.15.108.1 – 10.15.108.62	10.15.108.63
50	10.15.108.64/26	10.15.108.65 – 10.15.108.126	10.15.108.127
51	10.15.108.128/26	10.15.108.129 – 10.15.108.190	10.15.108.191
52	10.15.108.192/26	10.15.108.193 – 10.15.108.254	10.15.108.255
53	10.15.109.0/26	10.15.109.1 – 10.15.109.62	10.15.109.63
54	10.15.109.64/26	10.15.109.65 – 10.15.109.126	10.15.109.127
55	10.15.109.128/26	10.15.109.129 – 10.15.109.190	10.15.109.191
56	10.15.109.192/26	10.15.109.193 – 10.15.109.254	10.15.109.255
57	10.15.110.0/26	10.15.110.1 – 10.15.110.62	10.15.110.63
58	10.15.110.64/26	10.15.110.65 – 10.15.110.126	10.15.110.127
59	10.15.110.128/26	10.15.110.129 – 10.15.110.190	10.15.110.191
60	10.15.110.192/26	10.15.110.193 – 10.15.110.254	10.15.110.255
61	10.15.111.0/26	10.15.111.1 – 10.15.111.62	10.15.111.63
62	10.15.111.64/26	10.15.111.65 – 10.15.111.126	10.15.111.127
63	10.15.111.128/26	10.15.111.129 – 10.15.111.190	10.15.111.191
64	10.15.111.192/26	10.15.111.193 – 10.15.111.254	10.15.111.255

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 /20
/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	1
/21	255.255.248.0	2,048	2,046	2 split →
/22	255.255.252.0	1,024	1,022	4 split →
/23	255.255.254.0	512	510	8 split →
/24	255.255.255.0	256	254	16 split →
/25	255.255.255.128	128	126	32 split →
/26	255.255.255.192	64	62	64 split →
/27	255.255.255.224	32	30	128 split →
/28	255.255.255.240	16	14	256 split →
/29	255.255.255.248	8	6	512 split →
/30	255.255.255.252	4	2	1,024 split →
/31	255.255.255.254	2	2	2,048 split →
/32	255.255.255.255	1	1	4,096 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 →