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)10.91.48.0/20

network10.91.48.0/20

broadcast10.91.63.255

first host10.91.48.1

last host10.91.63.254

subnet mask255.255.240.0

wildcard0.0.15.255

addresses4,096

usable hosts4,094

classA

ipcalc 10.91.48.0/20

address00001010.01011011.00110000.00000000

subnet mask11111111.11111111.11110000.00000000

network00001010.01011011.00110000.00000000

broadcast00001010.01011011.00111111.11111111

green = network part, grey = host part

hex0x0a5b3000

decimal173748224

reverse dns0.48.91.10.in-addr.arpa

ipv4-mapped::ffff:a5b:3000

/20 split into /26 · 64 subnets

close ×

#	network	host range	broadcast
1	10.91.48.0/26	10.91.48.1 – 10.91.48.62	10.91.48.63
2	10.91.48.64/26	10.91.48.65 – 10.91.48.126	10.91.48.127
3	10.91.48.128/26	10.91.48.129 – 10.91.48.190	10.91.48.191
4	10.91.48.192/26	10.91.48.193 – 10.91.48.254	10.91.48.255
5	10.91.49.0/26	10.91.49.1 – 10.91.49.62	10.91.49.63
6	10.91.49.64/26	10.91.49.65 – 10.91.49.126	10.91.49.127
7	10.91.49.128/26	10.91.49.129 – 10.91.49.190	10.91.49.191
8	10.91.49.192/26	10.91.49.193 – 10.91.49.254	10.91.49.255
9	10.91.50.0/26	10.91.50.1 – 10.91.50.62	10.91.50.63
10	10.91.50.64/26	10.91.50.65 – 10.91.50.126	10.91.50.127
11	10.91.50.128/26	10.91.50.129 – 10.91.50.190	10.91.50.191
12	10.91.50.192/26	10.91.50.193 – 10.91.50.254	10.91.50.255
13	10.91.51.0/26	10.91.51.1 – 10.91.51.62	10.91.51.63
14	10.91.51.64/26	10.91.51.65 – 10.91.51.126	10.91.51.127
15	10.91.51.128/26	10.91.51.129 – 10.91.51.190	10.91.51.191
16	10.91.51.192/26	10.91.51.193 – 10.91.51.254	10.91.51.255
17	10.91.52.0/26	10.91.52.1 – 10.91.52.62	10.91.52.63
18	10.91.52.64/26	10.91.52.65 – 10.91.52.126	10.91.52.127
19	10.91.52.128/26	10.91.52.129 – 10.91.52.190	10.91.52.191
20	10.91.52.192/26	10.91.52.193 – 10.91.52.254	10.91.52.255
21	10.91.53.0/26	10.91.53.1 – 10.91.53.62	10.91.53.63
22	10.91.53.64/26	10.91.53.65 – 10.91.53.126	10.91.53.127
23	10.91.53.128/26	10.91.53.129 – 10.91.53.190	10.91.53.191
24	10.91.53.192/26	10.91.53.193 – 10.91.53.254	10.91.53.255
25	10.91.54.0/26	10.91.54.1 – 10.91.54.62	10.91.54.63
26	10.91.54.64/26	10.91.54.65 – 10.91.54.126	10.91.54.127
27	10.91.54.128/26	10.91.54.129 – 10.91.54.190	10.91.54.191
28	10.91.54.192/26	10.91.54.193 – 10.91.54.254	10.91.54.255
29	10.91.55.0/26	10.91.55.1 – 10.91.55.62	10.91.55.63
30	10.91.55.64/26	10.91.55.65 – 10.91.55.126	10.91.55.127
31	10.91.55.128/26	10.91.55.129 – 10.91.55.190	10.91.55.191
32	10.91.55.192/26	10.91.55.193 – 10.91.55.254	10.91.55.255
33	10.91.56.0/26	10.91.56.1 – 10.91.56.62	10.91.56.63
34	10.91.56.64/26	10.91.56.65 – 10.91.56.126	10.91.56.127
35	10.91.56.128/26	10.91.56.129 – 10.91.56.190	10.91.56.191
36	10.91.56.192/26	10.91.56.193 – 10.91.56.254	10.91.56.255
37	10.91.57.0/26	10.91.57.1 – 10.91.57.62	10.91.57.63
38	10.91.57.64/26	10.91.57.65 – 10.91.57.126	10.91.57.127
39	10.91.57.128/26	10.91.57.129 – 10.91.57.190	10.91.57.191
40	10.91.57.192/26	10.91.57.193 – 10.91.57.254	10.91.57.255
41	10.91.58.0/26	10.91.58.1 – 10.91.58.62	10.91.58.63
42	10.91.58.64/26	10.91.58.65 – 10.91.58.126	10.91.58.127
43	10.91.58.128/26	10.91.58.129 – 10.91.58.190	10.91.58.191
44	10.91.58.192/26	10.91.58.193 – 10.91.58.254	10.91.58.255
45	10.91.59.0/26	10.91.59.1 – 10.91.59.62	10.91.59.63
46	10.91.59.64/26	10.91.59.65 – 10.91.59.126	10.91.59.127
47	10.91.59.128/26	10.91.59.129 – 10.91.59.190	10.91.59.191
48	10.91.59.192/26	10.91.59.193 – 10.91.59.254	10.91.59.255
49	10.91.60.0/26	10.91.60.1 – 10.91.60.62	10.91.60.63
50	10.91.60.64/26	10.91.60.65 – 10.91.60.126	10.91.60.127
51	10.91.60.128/26	10.91.60.129 – 10.91.60.190	10.91.60.191
52	10.91.60.192/26	10.91.60.193 – 10.91.60.254	10.91.60.255
53	10.91.61.0/26	10.91.61.1 – 10.91.61.62	10.91.61.63
54	10.91.61.64/26	10.91.61.65 – 10.91.61.126	10.91.61.127
55	10.91.61.128/26	10.91.61.129 – 10.91.61.190	10.91.61.191
56	10.91.61.192/26	10.91.61.193 – 10.91.61.254	10.91.61.255
57	10.91.62.0/26	10.91.62.1 – 10.91.62.62	10.91.62.63
58	10.91.62.64/26	10.91.62.65 – 10.91.62.126	10.91.62.127
59	10.91.62.128/26	10.91.62.129 – 10.91.62.190	10.91.62.191
60	10.91.62.192/26	10.91.62.193 – 10.91.62.254	10.91.62.255
61	10.91.63.0/26	10.91.63.1 – 10.91.63.62	10.91.63.63
62	10.91.63.64/26	10.91.63.65 – 10.91.63.126	10.91.63.127
63	10.91.63.128/26	10.91.63.129 – 10.91.63.190	10.91.63.191
64	10.91.63.192/26	10.91.63.193 – 10.91.63.254	10.91.63.255

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 /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 →