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)10.2.99.64/27

network10.2.99.64/27

broadcast10.2.99.95

first host10.2.99.65

last host10.2.99.94

subnet mask255.255.255.224

wildcard0.0.0.31

addresses32

usable hosts30

classA

ipcalc 10.2.99.64/27

address00001010.00000010.01100011.01000000

subnet mask11111111.11111111.11111111.11100000

network00001010.00000010.01100011.01000000

broadcast00001010.00000010.01100011.01011111

green = network part, grey = host part

hex0x0a026340

decimal167928640

reverse dns64.99.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:6340

/27 split into /32 · 32 subnets

close ×

#	network	host range	broadcast
1	10.2.99.64/32	10.2.99.64 – 10.2.99.64	10.2.99.64
2	10.2.99.65/32	10.2.99.65 – 10.2.99.65	10.2.99.65
3	10.2.99.66/32	10.2.99.66 – 10.2.99.66	10.2.99.66
4	10.2.99.67/32	10.2.99.67 – 10.2.99.67	10.2.99.67
5	10.2.99.68/32	10.2.99.68 – 10.2.99.68	10.2.99.68
6	10.2.99.69/32	10.2.99.69 – 10.2.99.69	10.2.99.69
7	10.2.99.70/32	10.2.99.70 – 10.2.99.70	10.2.99.70
8	10.2.99.71/32	10.2.99.71 – 10.2.99.71	10.2.99.71
9	10.2.99.72/32	10.2.99.72 – 10.2.99.72	10.2.99.72
10	10.2.99.73/32	10.2.99.73 – 10.2.99.73	10.2.99.73
11	10.2.99.74/32	10.2.99.74 – 10.2.99.74	10.2.99.74
12	10.2.99.75/32	10.2.99.75 – 10.2.99.75	10.2.99.75
13	10.2.99.76/32	10.2.99.76 – 10.2.99.76	10.2.99.76
14	10.2.99.77/32	10.2.99.77 – 10.2.99.77	10.2.99.77
15	10.2.99.78/32	10.2.99.78 – 10.2.99.78	10.2.99.78
16	10.2.99.79/32	10.2.99.79 – 10.2.99.79	10.2.99.79
17	10.2.99.80/32	10.2.99.80 – 10.2.99.80	10.2.99.80
18	10.2.99.81/32	10.2.99.81 – 10.2.99.81	10.2.99.81
19	10.2.99.82/32	10.2.99.82 – 10.2.99.82	10.2.99.82
20	10.2.99.83/32	10.2.99.83 – 10.2.99.83	10.2.99.83
21	10.2.99.84/32	10.2.99.84 – 10.2.99.84	10.2.99.84
22	10.2.99.85/32	10.2.99.85 – 10.2.99.85	10.2.99.85
23	10.2.99.86/32	10.2.99.86 – 10.2.99.86	10.2.99.86
24	10.2.99.87/32	10.2.99.87 – 10.2.99.87	10.2.99.87
25	10.2.99.88/32	10.2.99.88 – 10.2.99.88	10.2.99.88
26	10.2.99.89/32	10.2.99.89 – 10.2.99.89	10.2.99.89
27	10.2.99.90/32	10.2.99.90 – 10.2.99.90	10.2.99.90
28	10.2.99.91/32	10.2.99.91 – 10.2.99.91	10.2.99.91
29	10.2.99.92/32	10.2.99.92 – 10.2.99.92	10.2.99.92
30	10.2.99.93/32	10.2.99.93 – 10.2.99.93	10.2.99.93
31	10.2.99.94/32	10.2.99.94 – 10.2.99.94	10.2.99.94
32	10.2.99.95/32	10.2.99.95 – 10.2.99.95	10.2.99.95

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 /27
/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	1
/28	255.255.255.240	16	14	2 split →
/29	255.255.255.248	8	6	4 split →
/30	255.255.255.252	4	2	8 split →
/31	255.255.255.254	2	2	16 split →
/32	255.255.255.255	1	1	32 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 →