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)10.0.9.0/25

network10.0.9.0/25

broadcast10.0.9.127

first host10.0.9.1

last host10.0.9.126

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.0.9.0/25

address00001010.00000000.00001001.00000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000000.00001001.00000000

broadcast00001010.00000000.00001001.01111111

green = network part, grey = host part

hex0x0a000900

decimal167774464

reverse dns0.9.0.10.in-addr.arpa

ipv4-mapped::ffff:a00:900

/25 split into /31 · 64 subnets

close ×

#	network	host range	broadcast
1	10.0.9.0/31	10.0.9.0 – 10.0.9.1	10.0.9.1
2	10.0.9.2/31	10.0.9.2 – 10.0.9.3	10.0.9.3
3	10.0.9.4/31	10.0.9.4 – 10.0.9.5	10.0.9.5
4	10.0.9.6/31	10.0.9.6 – 10.0.9.7	10.0.9.7
5	10.0.9.8/31	10.0.9.8 – 10.0.9.9	10.0.9.9
6	10.0.9.10/31	10.0.9.10 – 10.0.9.11	10.0.9.11
7	10.0.9.12/31	10.0.9.12 – 10.0.9.13	10.0.9.13
8	10.0.9.14/31	10.0.9.14 – 10.0.9.15	10.0.9.15
9	10.0.9.16/31	10.0.9.16 – 10.0.9.17	10.0.9.17
10	10.0.9.18/31	10.0.9.18 – 10.0.9.19	10.0.9.19
11	10.0.9.20/31	10.0.9.20 – 10.0.9.21	10.0.9.21
12	10.0.9.22/31	10.0.9.22 – 10.0.9.23	10.0.9.23
13	10.0.9.24/31	10.0.9.24 – 10.0.9.25	10.0.9.25
14	10.0.9.26/31	10.0.9.26 – 10.0.9.27	10.0.9.27
15	10.0.9.28/31	10.0.9.28 – 10.0.9.29	10.0.9.29
16	10.0.9.30/31	10.0.9.30 – 10.0.9.31	10.0.9.31
17	10.0.9.32/31	10.0.9.32 – 10.0.9.33	10.0.9.33
18	10.0.9.34/31	10.0.9.34 – 10.0.9.35	10.0.9.35
19	10.0.9.36/31	10.0.9.36 – 10.0.9.37	10.0.9.37
20	10.0.9.38/31	10.0.9.38 – 10.0.9.39	10.0.9.39
21	10.0.9.40/31	10.0.9.40 – 10.0.9.41	10.0.9.41
22	10.0.9.42/31	10.0.9.42 – 10.0.9.43	10.0.9.43
23	10.0.9.44/31	10.0.9.44 – 10.0.9.45	10.0.9.45
24	10.0.9.46/31	10.0.9.46 – 10.0.9.47	10.0.9.47
25	10.0.9.48/31	10.0.9.48 – 10.0.9.49	10.0.9.49
26	10.0.9.50/31	10.0.9.50 – 10.0.9.51	10.0.9.51
27	10.0.9.52/31	10.0.9.52 – 10.0.9.53	10.0.9.53
28	10.0.9.54/31	10.0.9.54 – 10.0.9.55	10.0.9.55
29	10.0.9.56/31	10.0.9.56 – 10.0.9.57	10.0.9.57
30	10.0.9.58/31	10.0.9.58 – 10.0.9.59	10.0.9.59
31	10.0.9.60/31	10.0.9.60 – 10.0.9.61	10.0.9.61
32	10.0.9.62/31	10.0.9.62 – 10.0.9.63	10.0.9.63
33	10.0.9.64/31	10.0.9.64 – 10.0.9.65	10.0.9.65
34	10.0.9.66/31	10.0.9.66 – 10.0.9.67	10.0.9.67
35	10.0.9.68/31	10.0.9.68 – 10.0.9.69	10.0.9.69
36	10.0.9.70/31	10.0.9.70 – 10.0.9.71	10.0.9.71
37	10.0.9.72/31	10.0.9.72 – 10.0.9.73	10.0.9.73
38	10.0.9.74/31	10.0.9.74 – 10.0.9.75	10.0.9.75
39	10.0.9.76/31	10.0.9.76 – 10.0.9.77	10.0.9.77
40	10.0.9.78/31	10.0.9.78 – 10.0.9.79	10.0.9.79
41	10.0.9.80/31	10.0.9.80 – 10.0.9.81	10.0.9.81
42	10.0.9.82/31	10.0.9.82 – 10.0.9.83	10.0.9.83
43	10.0.9.84/31	10.0.9.84 – 10.0.9.85	10.0.9.85
44	10.0.9.86/31	10.0.9.86 – 10.0.9.87	10.0.9.87
45	10.0.9.88/31	10.0.9.88 – 10.0.9.89	10.0.9.89
46	10.0.9.90/31	10.0.9.90 – 10.0.9.91	10.0.9.91
47	10.0.9.92/31	10.0.9.92 – 10.0.9.93	10.0.9.93
48	10.0.9.94/31	10.0.9.94 – 10.0.9.95	10.0.9.95
49	10.0.9.96/31	10.0.9.96 – 10.0.9.97	10.0.9.97
50	10.0.9.98/31	10.0.9.98 – 10.0.9.99	10.0.9.99
51	10.0.9.100/31	10.0.9.100 – 10.0.9.101	10.0.9.101
52	10.0.9.102/31	10.0.9.102 – 10.0.9.103	10.0.9.103
53	10.0.9.104/31	10.0.9.104 – 10.0.9.105	10.0.9.105
54	10.0.9.106/31	10.0.9.106 – 10.0.9.107	10.0.9.107
55	10.0.9.108/31	10.0.9.108 – 10.0.9.109	10.0.9.109
56	10.0.9.110/31	10.0.9.110 – 10.0.9.111	10.0.9.111
57	10.0.9.112/31	10.0.9.112 – 10.0.9.113	10.0.9.113
58	10.0.9.114/31	10.0.9.114 – 10.0.9.115	10.0.9.115
59	10.0.9.116/31	10.0.9.116 – 10.0.9.117	10.0.9.117
60	10.0.9.118/31	10.0.9.118 – 10.0.9.119	10.0.9.119
61	10.0.9.120/31	10.0.9.120 – 10.0.9.121	10.0.9.121
62	10.0.9.122/31	10.0.9.122 – 10.0.9.123	10.0.9.123
63	10.0.9.124/31	10.0.9.124 – 10.0.9.125	10.0.9.125
64	10.0.9.126/31	10.0.9.126 – 10.0.9.127	10.0.9.127

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 /25
/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	1
/26	255.255.255.192	64	62	2 split →
/27	255.255.255.224	32	30	4 split →
/28	255.255.255.240	16	14	8 split →
/29	255.255.255.248	8	6	16 split →
/30	255.255.255.252	4	2	32 split →
/31	255.255.255.254	2	2	64 split →
/32	255.255.255.255	1	1	128 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 →