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)10.15.0.0/18

network10.15.0.0/18

broadcast10.15.63.255

first host10.15.0.1

last host10.15.63.254

subnet mask255.255.192.0

wildcard0.0.63.255

addresses16,384

usable hosts16,382

classA

ipcalc 10.15.0.0/18

address00001010.00001111.00000000.00000000

subnet mask11111111.11111111.11000000.00000000

network00001010.00001111.00000000.00000000

broadcast00001010.00001111.00111111.11111111

green = network part, grey = host part

hex0x0a0f0000

decimal168755200

reverse dns0.0.15.10.in-addr.arpa

ipv4-mapped::ffff:a0f:0

/18 split into /24 · 64 subnets

close ×

#	network	host range	broadcast
1	10.15.0.0/24	10.15.0.1 – 10.15.0.254	10.15.0.255
2	10.15.1.0/24	10.15.1.1 – 10.15.1.254	10.15.1.255
3	10.15.2.0/24	10.15.2.1 – 10.15.2.254	10.15.2.255
4	10.15.3.0/24	10.15.3.1 – 10.15.3.254	10.15.3.255
5	10.15.4.0/24	10.15.4.1 – 10.15.4.254	10.15.4.255
6	10.15.5.0/24	10.15.5.1 – 10.15.5.254	10.15.5.255
7	10.15.6.0/24	10.15.6.1 – 10.15.6.254	10.15.6.255
8	10.15.7.0/24	10.15.7.1 – 10.15.7.254	10.15.7.255
9	10.15.8.0/24	10.15.8.1 – 10.15.8.254	10.15.8.255
10	10.15.9.0/24	10.15.9.1 – 10.15.9.254	10.15.9.255
11	10.15.10.0/24	10.15.10.1 – 10.15.10.254	10.15.10.255
12	10.15.11.0/24	10.15.11.1 – 10.15.11.254	10.15.11.255
13	10.15.12.0/24	10.15.12.1 – 10.15.12.254	10.15.12.255
14	10.15.13.0/24	10.15.13.1 – 10.15.13.254	10.15.13.255
15	10.15.14.0/24	10.15.14.1 – 10.15.14.254	10.15.14.255
16	10.15.15.0/24	10.15.15.1 – 10.15.15.254	10.15.15.255
17	10.15.16.0/24	10.15.16.1 – 10.15.16.254	10.15.16.255
18	10.15.17.0/24	10.15.17.1 – 10.15.17.254	10.15.17.255
19	10.15.18.0/24	10.15.18.1 – 10.15.18.254	10.15.18.255
20	10.15.19.0/24	10.15.19.1 – 10.15.19.254	10.15.19.255
21	10.15.20.0/24	10.15.20.1 – 10.15.20.254	10.15.20.255
22	10.15.21.0/24	10.15.21.1 – 10.15.21.254	10.15.21.255
23	10.15.22.0/24	10.15.22.1 – 10.15.22.254	10.15.22.255
24	10.15.23.0/24	10.15.23.1 – 10.15.23.254	10.15.23.255
25	10.15.24.0/24	10.15.24.1 – 10.15.24.254	10.15.24.255
26	10.15.25.0/24	10.15.25.1 – 10.15.25.254	10.15.25.255
27	10.15.26.0/24	10.15.26.1 – 10.15.26.254	10.15.26.255
28	10.15.27.0/24	10.15.27.1 – 10.15.27.254	10.15.27.255
29	10.15.28.0/24	10.15.28.1 – 10.15.28.254	10.15.28.255
30	10.15.29.0/24	10.15.29.1 – 10.15.29.254	10.15.29.255
31	10.15.30.0/24	10.15.30.1 – 10.15.30.254	10.15.30.255
32	10.15.31.0/24	10.15.31.1 – 10.15.31.254	10.15.31.255
33	10.15.32.0/24	10.15.32.1 – 10.15.32.254	10.15.32.255
34	10.15.33.0/24	10.15.33.1 – 10.15.33.254	10.15.33.255
35	10.15.34.0/24	10.15.34.1 – 10.15.34.254	10.15.34.255
36	10.15.35.0/24	10.15.35.1 – 10.15.35.254	10.15.35.255
37	10.15.36.0/24	10.15.36.1 – 10.15.36.254	10.15.36.255
38	10.15.37.0/24	10.15.37.1 – 10.15.37.254	10.15.37.255
39	10.15.38.0/24	10.15.38.1 – 10.15.38.254	10.15.38.255
40	10.15.39.0/24	10.15.39.1 – 10.15.39.254	10.15.39.255
41	10.15.40.0/24	10.15.40.1 – 10.15.40.254	10.15.40.255
42	10.15.41.0/24	10.15.41.1 – 10.15.41.254	10.15.41.255
43	10.15.42.0/24	10.15.42.1 – 10.15.42.254	10.15.42.255
44	10.15.43.0/24	10.15.43.1 – 10.15.43.254	10.15.43.255
45	10.15.44.0/24	10.15.44.1 – 10.15.44.254	10.15.44.255
46	10.15.45.0/24	10.15.45.1 – 10.15.45.254	10.15.45.255
47	10.15.46.0/24	10.15.46.1 – 10.15.46.254	10.15.46.255
48	10.15.47.0/24	10.15.47.1 – 10.15.47.254	10.15.47.255
49	10.15.48.0/24	10.15.48.1 – 10.15.48.254	10.15.48.255
50	10.15.49.0/24	10.15.49.1 – 10.15.49.254	10.15.49.255
51	10.15.50.0/24	10.15.50.1 – 10.15.50.254	10.15.50.255
52	10.15.51.0/24	10.15.51.1 – 10.15.51.254	10.15.51.255
53	10.15.52.0/24	10.15.52.1 – 10.15.52.254	10.15.52.255
54	10.15.53.0/24	10.15.53.1 – 10.15.53.254	10.15.53.255
55	10.15.54.0/24	10.15.54.1 – 10.15.54.254	10.15.54.255
56	10.15.55.0/24	10.15.55.1 – 10.15.55.254	10.15.55.255
57	10.15.56.0/24	10.15.56.1 – 10.15.56.254	10.15.56.255
58	10.15.57.0/24	10.15.57.1 – 10.15.57.254	10.15.57.255
59	10.15.58.0/24	10.15.58.1 – 10.15.58.254	10.15.58.255
60	10.15.59.0/24	10.15.59.1 – 10.15.59.254	10.15.59.255
61	10.15.60.0/24	10.15.60.1 – 10.15.60.254	10.15.60.255
62	10.15.61.0/24	10.15.61.1 – 10.15.61.254	10.15.61.255
63	10.15.62.0/24	10.15.62.1 – 10.15.62.254	10.15.62.255
64	10.15.63.0/24	10.15.63.1 – 10.15.63.254	10.15.63.255

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 /18
/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	1
/19	255.255.224.0	8,192	8,190	2 split →
/20	255.255.240.0	4,096	4,094	4 split →
/21	255.255.248.0	2,048	2,046	8 split →
/22	255.255.252.0	1,024	1,022	16 split →
/23	255.255.254.0	512	510	32 split →
/24	255.255.255.0	256	254	64 split →
/25	255.255.255.128	128	126	128 split →
/26	255.255.255.192	64	62	256 split →
/27	255.255.255.224	32	30	512 split →
/28	255.255.255.240	16	14	1,024 split →
/29	255.255.255.248	8	6	2,048 split →
/30	255.255.255.252	4	2	4,096 split →
/31	255.255.255.254	2	2	8,192 split →
/32	255.255.255.255	1	1	16,384 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 →