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)10.0.0.0/12

network10.0.0.0/12

broadcast10.15.255.255

first host10.0.0.1

last host10.15.255.254

subnet mask255.240.0.0

wildcard0.15.255.255

addresses1,048,576

usable hosts1,048,574

classA

ipcalc 10.0.0.0/12

address00001010.00000000.00000000.00000000

subnet mask11111111.11110000.00000000.00000000

network00001010.00000000.00000000.00000000

broadcast00001010.00001111.11111111.11111111

green = network part, grey = host part

hex0x0a000000

decimal167772160

reverse dns0.0.0.10.in-addr.arpa

ipv4-mapped::ffff:a00:0

/12 split into /19 · 128 subnets

close ×

#	network	host range	broadcast
1	10.0.0.0/19	10.0.0.1 – 10.0.31.254	10.0.31.255
2	10.0.32.0/19	10.0.32.1 – 10.0.63.254	10.0.63.255
3	10.0.64.0/19	10.0.64.1 – 10.0.95.254	10.0.95.255
4	10.0.96.0/19	10.0.96.1 – 10.0.127.254	10.0.127.255
5	10.0.128.0/19	10.0.128.1 – 10.0.159.254	10.0.159.255
6	10.0.160.0/19	10.0.160.1 – 10.0.191.254	10.0.191.255
7	10.0.192.0/19	10.0.192.1 – 10.0.223.254	10.0.223.255
8	10.0.224.0/19	10.0.224.1 – 10.0.255.254	10.0.255.255
9	10.1.0.0/19	10.1.0.1 – 10.1.31.254	10.1.31.255
10	10.1.32.0/19	10.1.32.1 – 10.1.63.254	10.1.63.255
11	10.1.64.0/19	10.1.64.1 – 10.1.95.254	10.1.95.255
12	10.1.96.0/19	10.1.96.1 – 10.1.127.254	10.1.127.255
13	10.1.128.0/19	10.1.128.1 – 10.1.159.254	10.1.159.255
14	10.1.160.0/19	10.1.160.1 – 10.1.191.254	10.1.191.255
15	10.1.192.0/19	10.1.192.1 – 10.1.223.254	10.1.223.255
16	10.1.224.0/19	10.1.224.1 – 10.1.255.254	10.1.255.255
17	10.2.0.0/19	10.2.0.1 – 10.2.31.254	10.2.31.255
18	10.2.32.0/19	10.2.32.1 – 10.2.63.254	10.2.63.255
19	10.2.64.0/19	10.2.64.1 – 10.2.95.254	10.2.95.255
20	10.2.96.0/19	10.2.96.1 – 10.2.127.254	10.2.127.255
21	10.2.128.0/19	10.2.128.1 – 10.2.159.254	10.2.159.255
22	10.2.160.0/19	10.2.160.1 – 10.2.191.254	10.2.191.255
23	10.2.192.0/19	10.2.192.1 – 10.2.223.254	10.2.223.255
24	10.2.224.0/19	10.2.224.1 – 10.2.255.254	10.2.255.255
25	10.3.0.0/19	10.3.0.1 – 10.3.31.254	10.3.31.255
26	10.3.32.0/19	10.3.32.1 – 10.3.63.254	10.3.63.255
27	10.3.64.0/19	10.3.64.1 – 10.3.95.254	10.3.95.255
28	10.3.96.0/19	10.3.96.1 – 10.3.127.254	10.3.127.255
29	10.3.128.0/19	10.3.128.1 – 10.3.159.254	10.3.159.255
30	10.3.160.0/19	10.3.160.1 – 10.3.191.254	10.3.191.255
31	10.3.192.0/19	10.3.192.1 – 10.3.223.254	10.3.223.255
32	10.3.224.0/19	10.3.224.1 – 10.3.255.254	10.3.255.255
33	10.4.0.0/19	10.4.0.1 – 10.4.31.254	10.4.31.255
34	10.4.32.0/19	10.4.32.1 – 10.4.63.254	10.4.63.255
35	10.4.64.0/19	10.4.64.1 – 10.4.95.254	10.4.95.255
36	10.4.96.0/19	10.4.96.1 – 10.4.127.254	10.4.127.255
37	10.4.128.0/19	10.4.128.1 – 10.4.159.254	10.4.159.255
38	10.4.160.0/19	10.4.160.1 – 10.4.191.254	10.4.191.255
39	10.4.192.0/19	10.4.192.1 – 10.4.223.254	10.4.223.255
40	10.4.224.0/19	10.4.224.1 – 10.4.255.254	10.4.255.255
41	10.5.0.0/19	10.5.0.1 – 10.5.31.254	10.5.31.255
42	10.5.32.0/19	10.5.32.1 – 10.5.63.254	10.5.63.255
43	10.5.64.0/19	10.5.64.1 – 10.5.95.254	10.5.95.255
44	10.5.96.0/19	10.5.96.1 – 10.5.127.254	10.5.127.255
45	10.5.128.0/19	10.5.128.1 – 10.5.159.254	10.5.159.255
46	10.5.160.0/19	10.5.160.1 – 10.5.191.254	10.5.191.255
47	10.5.192.0/19	10.5.192.1 – 10.5.223.254	10.5.223.255
48	10.5.224.0/19	10.5.224.1 – 10.5.255.254	10.5.255.255
49	10.6.0.0/19	10.6.0.1 – 10.6.31.254	10.6.31.255
50	10.6.32.0/19	10.6.32.1 – 10.6.63.254	10.6.63.255
51	10.6.64.0/19	10.6.64.1 – 10.6.95.254	10.6.95.255
52	10.6.96.0/19	10.6.96.1 – 10.6.127.254	10.6.127.255
53	10.6.128.0/19	10.6.128.1 – 10.6.159.254	10.6.159.255
54	10.6.160.0/19	10.6.160.1 – 10.6.191.254	10.6.191.255
55	10.6.192.0/19	10.6.192.1 – 10.6.223.254	10.6.223.255
56	10.6.224.0/19	10.6.224.1 – 10.6.255.254	10.6.255.255
57	10.7.0.0/19	10.7.0.1 – 10.7.31.254	10.7.31.255
58	10.7.32.0/19	10.7.32.1 – 10.7.63.254	10.7.63.255
59	10.7.64.0/19	10.7.64.1 – 10.7.95.254	10.7.95.255
60	10.7.96.0/19	10.7.96.1 – 10.7.127.254	10.7.127.255
61	10.7.128.0/19	10.7.128.1 – 10.7.159.254	10.7.159.255
62	10.7.160.0/19	10.7.160.1 – 10.7.191.254	10.7.191.255
63	10.7.192.0/19	10.7.192.1 – 10.7.223.254	10.7.223.255
64	10.7.224.0/19	10.7.224.1 – 10.7.255.254	10.7.255.255
65	10.8.0.0/19	10.8.0.1 – 10.8.31.254	10.8.31.255
66	10.8.32.0/19	10.8.32.1 – 10.8.63.254	10.8.63.255
67	10.8.64.0/19	10.8.64.1 – 10.8.95.254	10.8.95.255
68	10.8.96.0/19	10.8.96.1 – 10.8.127.254	10.8.127.255
69	10.8.128.0/19	10.8.128.1 – 10.8.159.254	10.8.159.255
70	10.8.160.0/19	10.8.160.1 – 10.8.191.254	10.8.191.255
71	10.8.192.0/19	10.8.192.1 – 10.8.223.254	10.8.223.255
72	10.8.224.0/19	10.8.224.1 – 10.8.255.254	10.8.255.255
73	10.9.0.0/19	10.9.0.1 – 10.9.31.254	10.9.31.255
74	10.9.32.0/19	10.9.32.1 – 10.9.63.254	10.9.63.255
75	10.9.64.0/19	10.9.64.1 – 10.9.95.254	10.9.95.255
76	10.9.96.0/19	10.9.96.1 – 10.9.127.254	10.9.127.255
77	10.9.128.0/19	10.9.128.1 – 10.9.159.254	10.9.159.255
78	10.9.160.0/19	10.9.160.1 – 10.9.191.254	10.9.191.255
79	10.9.192.0/19	10.9.192.1 – 10.9.223.254	10.9.223.255
80	10.9.224.0/19	10.9.224.1 – 10.9.255.254	10.9.255.255
81	10.10.0.0/19	10.10.0.1 – 10.10.31.254	10.10.31.255
82	10.10.32.0/19	10.10.32.1 – 10.10.63.254	10.10.63.255
83	10.10.64.0/19	10.10.64.1 – 10.10.95.254	10.10.95.255
84	10.10.96.0/19	10.10.96.1 – 10.10.127.254	10.10.127.255
85	10.10.128.0/19	10.10.128.1 – 10.10.159.254	10.10.159.255
86	10.10.160.0/19	10.10.160.1 – 10.10.191.254	10.10.191.255
87	10.10.192.0/19	10.10.192.1 – 10.10.223.254	10.10.223.255
88	10.10.224.0/19	10.10.224.1 – 10.10.255.254	10.10.255.255
89	10.11.0.0/19	10.11.0.1 – 10.11.31.254	10.11.31.255
90	10.11.32.0/19	10.11.32.1 – 10.11.63.254	10.11.63.255
91	10.11.64.0/19	10.11.64.1 – 10.11.95.254	10.11.95.255
92	10.11.96.0/19	10.11.96.1 – 10.11.127.254	10.11.127.255
93	10.11.128.0/19	10.11.128.1 – 10.11.159.254	10.11.159.255
94	10.11.160.0/19	10.11.160.1 – 10.11.191.254	10.11.191.255
95	10.11.192.0/19	10.11.192.1 – 10.11.223.254	10.11.223.255
96	10.11.224.0/19	10.11.224.1 – 10.11.255.254	10.11.255.255
97	10.12.0.0/19	10.12.0.1 – 10.12.31.254	10.12.31.255
98	10.12.32.0/19	10.12.32.1 – 10.12.63.254	10.12.63.255
99	10.12.64.0/19	10.12.64.1 – 10.12.95.254	10.12.95.255
100	10.12.96.0/19	10.12.96.1 – 10.12.127.254	10.12.127.255
101	10.12.128.0/19	10.12.128.1 – 10.12.159.254	10.12.159.255
102	10.12.160.0/19	10.12.160.1 – 10.12.191.254	10.12.191.255
103	10.12.192.0/19	10.12.192.1 – 10.12.223.254	10.12.223.255
104	10.12.224.0/19	10.12.224.1 – 10.12.255.254	10.12.255.255
105	10.13.0.0/19	10.13.0.1 – 10.13.31.254	10.13.31.255
106	10.13.32.0/19	10.13.32.1 – 10.13.63.254	10.13.63.255
107	10.13.64.0/19	10.13.64.1 – 10.13.95.254	10.13.95.255
108	10.13.96.0/19	10.13.96.1 – 10.13.127.254	10.13.127.255
109	10.13.128.0/19	10.13.128.1 – 10.13.159.254	10.13.159.255
110	10.13.160.0/19	10.13.160.1 – 10.13.191.254	10.13.191.255
111	10.13.192.0/19	10.13.192.1 – 10.13.223.254	10.13.223.255
112	10.13.224.0/19	10.13.224.1 – 10.13.255.254	10.13.255.255
113	10.14.0.0/19	10.14.0.1 – 10.14.31.254	10.14.31.255
114	10.14.32.0/19	10.14.32.1 – 10.14.63.254	10.14.63.255
115	10.14.64.0/19	10.14.64.1 – 10.14.95.254	10.14.95.255
116	10.14.96.0/19	10.14.96.1 – 10.14.127.254	10.14.127.255
117	10.14.128.0/19	10.14.128.1 – 10.14.159.254	10.14.159.255
118	10.14.160.0/19	10.14.160.1 – 10.14.191.254	10.14.191.255
119	10.14.192.0/19	10.14.192.1 – 10.14.223.254	10.14.223.255
120	10.14.224.0/19	10.14.224.1 – 10.14.255.254	10.14.255.255
121	10.15.0.0/19	10.15.0.1 – 10.15.31.254	10.15.31.255
122	10.15.32.0/19	10.15.32.1 – 10.15.63.254	10.15.63.255
123	10.15.64.0/19	10.15.64.1 – 10.15.95.254	10.15.95.255
124	10.15.96.0/19	10.15.96.1 – 10.15.127.254	10.15.127.255
125	10.15.128.0/19	10.15.128.1 – 10.15.159.254	10.15.159.255
126	10.15.160.0/19	10.15.160.1 – 10.15.191.254	10.15.191.255
127	10.15.192.0/19	10.15.192.1 – 10.15.223.254	10.15.223.255
128	10.15.224.0/19	10.15.224.1 – 10.15.255.254	10.15.255.255

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 /12
/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	1
/13	255.248.0.0	524,288	524,286	2 split →
/14	255.252.0.0	262,144	262,142	4 split →
/15	255.254.0.0	131,072	131,070	8 split →
/16	255.255.0.0	65,536	65,534	16 split →
/17	255.255.128.0	32,768	32,766	32 split →
/18	255.255.192.0	16,384	16,382	64 split →
/19	255.255.224.0	8,192	8,190	128 split →
/20	255.255.240.0	4,096	4,094	256 split →
/21	255.255.248.0	2,048	2,046	512 split →
/22	255.255.252.0	1,024	1,022	1,024 split →
/23	255.255.254.0	512	510	2,048 split →
/24	255.255.255.0	256	254	4,096 split →
/25	255.255.255.128	128	126	8,192 split →
/26	255.255.255.192	64	62	16,384 split →
/27	255.255.255.224	32	30	32,768 split →
/28	255.255.255.240	16	14	65,536 split →
/29	255.255.255.248	8	6	131,072 split →
/30	255.255.255.252	4	2	262,144 split →
/31	255.255.255.254	2	2	524,288 split →
/32	255.255.255.255	1	1	1,048,576 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 →