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)10.167.100.0/25

network10.167.100.0/25

broadcast10.167.100.127

first host10.167.100.1

last host10.167.100.126

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.167.100.0/25

address00001010.10100111.01100100.00000000

subnet mask11111111.11111111.11111111.10000000

network00001010.10100111.01100100.00000000

broadcast00001010.10100111.01100100.01111111

green = network part, grey = host part

hex0x0aa76400

decimal178742272

reverse dns0.100.167.10.in-addr.arpa

ipv4-mapped::ffff:aa7:6400

/25 split into /31 · 64 subnets

close ×

#	network	host range	broadcast
1	10.167.100.0/31	10.167.100.0 – 10.167.100.1	10.167.100.1
2	10.167.100.2/31	10.167.100.2 – 10.167.100.3	10.167.100.3
3	10.167.100.4/31	10.167.100.4 – 10.167.100.5	10.167.100.5
4	10.167.100.6/31	10.167.100.6 – 10.167.100.7	10.167.100.7
5	10.167.100.8/31	10.167.100.8 – 10.167.100.9	10.167.100.9
6	10.167.100.10/31	10.167.100.10 – 10.167.100.11	10.167.100.11
7	10.167.100.12/31	10.167.100.12 – 10.167.100.13	10.167.100.13
8	10.167.100.14/31	10.167.100.14 – 10.167.100.15	10.167.100.15
9	10.167.100.16/31	10.167.100.16 – 10.167.100.17	10.167.100.17
10	10.167.100.18/31	10.167.100.18 – 10.167.100.19	10.167.100.19
11	10.167.100.20/31	10.167.100.20 – 10.167.100.21	10.167.100.21
12	10.167.100.22/31	10.167.100.22 – 10.167.100.23	10.167.100.23
13	10.167.100.24/31	10.167.100.24 – 10.167.100.25	10.167.100.25
14	10.167.100.26/31	10.167.100.26 – 10.167.100.27	10.167.100.27
15	10.167.100.28/31	10.167.100.28 – 10.167.100.29	10.167.100.29
16	10.167.100.30/31	10.167.100.30 – 10.167.100.31	10.167.100.31
17	10.167.100.32/31	10.167.100.32 – 10.167.100.33	10.167.100.33
18	10.167.100.34/31	10.167.100.34 – 10.167.100.35	10.167.100.35
19	10.167.100.36/31	10.167.100.36 – 10.167.100.37	10.167.100.37
20	10.167.100.38/31	10.167.100.38 – 10.167.100.39	10.167.100.39
21	10.167.100.40/31	10.167.100.40 – 10.167.100.41	10.167.100.41
22	10.167.100.42/31	10.167.100.42 – 10.167.100.43	10.167.100.43
23	10.167.100.44/31	10.167.100.44 – 10.167.100.45	10.167.100.45
24	10.167.100.46/31	10.167.100.46 – 10.167.100.47	10.167.100.47
25	10.167.100.48/31	10.167.100.48 – 10.167.100.49	10.167.100.49
26	10.167.100.50/31	10.167.100.50 – 10.167.100.51	10.167.100.51
27	10.167.100.52/31	10.167.100.52 – 10.167.100.53	10.167.100.53
28	10.167.100.54/31	10.167.100.54 – 10.167.100.55	10.167.100.55
29	10.167.100.56/31	10.167.100.56 – 10.167.100.57	10.167.100.57
30	10.167.100.58/31	10.167.100.58 – 10.167.100.59	10.167.100.59
31	10.167.100.60/31	10.167.100.60 – 10.167.100.61	10.167.100.61
32	10.167.100.62/31	10.167.100.62 – 10.167.100.63	10.167.100.63
33	10.167.100.64/31	10.167.100.64 – 10.167.100.65	10.167.100.65
34	10.167.100.66/31	10.167.100.66 – 10.167.100.67	10.167.100.67
35	10.167.100.68/31	10.167.100.68 – 10.167.100.69	10.167.100.69
36	10.167.100.70/31	10.167.100.70 – 10.167.100.71	10.167.100.71
37	10.167.100.72/31	10.167.100.72 – 10.167.100.73	10.167.100.73
38	10.167.100.74/31	10.167.100.74 – 10.167.100.75	10.167.100.75
39	10.167.100.76/31	10.167.100.76 – 10.167.100.77	10.167.100.77
40	10.167.100.78/31	10.167.100.78 – 10.167.100.79	10.167.100.79
41	10.167.100.80/31	10.167.100.80 – 10.167.100.81	10.167.100.81
42	10.167.100.82/31	10.167.100.82 – 10.167.100.83	10.167.100.83
43	10.167.100.84/31	10.167.100.84 – 10.167.100.85	10.167.100.85
44	10.167.100.86/31	10.167.100.86 – 10.167.100.87	10.167.100.87
45	10.167.100.88/31	10.167.100.88 – 10.167.100.89	10.167.100.89
46	10.167.100.90/31	10.167.100.90 – 10.167.100.91	10.167.100.91
47	10.167.100.92/31	10.167.100.92 – 10.167.100.93	10.167.100.93
48	10.167.100.94/31	10.167.100.94 – 10.167.100.95	10.167.100.95
49	10.167.100.96/31	10.167.100.96 – 10.167.100.97	10.167.100.97
50	10.167.100.98/31	10.167.100.98 – 10.167.100.99	10.167.100.99
51	10.167.100.100/31	10.167.100.100 – 10.167.100.101	10.167.100.101
52	10.167.100.102/31	10.167.100.102 – 10.167.100.103	10.167.100.103
53	10.167.100.104/31	10.167.100.104 – 10.167.100.105	10.167.100.105
54	10.167.100.106/31	10.167.100.106 – 10.167.100.107	10.167.100.107
55	10.167.100.108/31	10.167.100.108 – 10.167.100.109	10.167.100.109
56	10.167.100.110/31	10.167.100.110 – 10.167.100.111	10.167.100.111
57	10.167.100.112/31	10.167.100.112 – 10.167.100.113	10.167.100.113
58	10.167.100.114/31	10.167.100.114 – 10.167.100.115	10.167.100.115
59	10.167.100.116/31	10.167.100.116 – 10.167.100.117	10.167.100.117
60	10.167.100.118/31	10.167.100.118 – 10.167.100.119	10.167.100.119
61	10.167.100.120/31	10.167.100.120 – 10.167.100.121	10.167.100.121
62	10.167.100.122/31	10.167.100.122 – 10.167.100.123	10.167.100.123
63	10.167.100.124/31	10.167.100.124 – 10.167.100.125	10.167.100.125
64	10.167.100.126/31	10.167.100.126 – 10.167.100.127	10.167.100.127

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 →