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)10.167.51.0/24

network10.167.51.0/24

broadcast10.167.51.255

first host10.167.51.1

last host10.167.51.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.167.51.0/24

address00001010.10100111.00110011.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.10100111.00110011.00000000

broadcast00001010.10100111.00110011.11111111

green = network part, grey = host part

hex0x0aa73300

decimal178729728

reverse dns0.51.167.10.in-addr.arpa

ipv4-mapped::ffff:aa7:3300

/24 split into /30 · 64 subnets

close ×

#	network	host range	broadcast
1	10.167.51.0/30	10.167.51.1 – 10.167.51.2	10.167.51.3
2	10.167.51.4/30	10.167.51.5 – 10.167.51.6	10.167.51.7
3	10.167.51.8/30	10.167.51.9 – 10.167.51.10	10.167.51.11
4	10.167.51.12/30	10.167.51.13 – 10.167.51.14	10.167.51.15
5	10.167.51.16/30	10.167.51.17 – 10.167.51.18	10.167.51.19
6	10.167.51.20/30	10.167.51.21 – 10.167.51.22	10.167.51.23
7	10.167.51.24/30	10.167.51.25 – 10.167.51.26	10.167.51.27
8	10.167.51.28/30	10.167.51.29 – 10.167.51.30	10.167.51.31
9	10.167.51.32/30	10.167.51.33 – 10.167.51.34	10.167.51.35
10	10.167.51.36/30	10.167.51.37 – 10.167.51.38	10.167.51.39
11	10.167.51.40/30	10.167.51.41 – 10.167.51.42	10.167.51.43
12	10.167.51.44/30	10.167.51.45 – 10.167.51.46	10.167.51.47
13	10.167.51.48/30	10.167.51.49 – 10.167.51.50	10.167.51.51
14	10.167.51.52/30	10.167.51.53 – 10.167.51.54	10.167.51.55
15	10.167.51.56/30	10.167.51.57 – 10.167.51.58	10.167.51.59
16	10.167.51.60/30	10.167.51.61 – 10.167.51.62	10.167.51.63
17	10.167.51.64/30	10.167.51.65 – 10.167.51.66	10.167.51.67
18	10.167.51.68/30	10.167.51.69 – 10.167.51.70	10.167.51.71
19	10.167.51.72/30	10.167.51.73 – 10.167.51.74	10.167.51.75
20	10.167.51.76/30	10.167.51.77 – 10.167.51.78	10.167.51.79
21	10.167.51.80/30	10.167.51.81 – 10.167.51.82	10.167.51.83
22	10.167.51.84/30	10.167.51.85 – 10.167.51.86	10.167.51.87
23	10.167.51.88/30	10.167.51.89 – 10.167.51.90	10.167.51.91
24	10.167.51.92/30	10.167.51.93 – 10.167.51.94	10.167.51.95
25	10.167.51.96/30	10.167.51.97 – 10.167.51.98	10.167.51.99
26	10.167.51.100/30	10.167.51.101 – 10.167.51.102	10.167.51.103
27	10.167.51.104/30	10.167.51.105 – 10.167.51.106	10.167.51.107
28	10.167.51.108/30	10.167.51.109 – 10.167.51.110	10.167.51.111
29	10.167.51.112/30	10.167.51.113 – 10.167.51.114	10.167.51.115
30	10.167.51.116/30	10.167.51.117 – 10.167.51.118	10.167.51.119
31	10.167.51.120/30	10.167.51.121 – 10.167.51.122	10.167.51.123
32	10.167.51.124/30	10.167.51.125 – 10.167.51.126	10.167.51.127
33	10.167.51.128/30	10.167.51.129 – 10.167.51.130	10.167.51.131
34	10.167.51.132/30	10.167.51.133 – 10.167.51.134	10.167.51.135
35	10.167.51.136/30	10.167.51.137 – 10.167.51.138	10.167.51.139
36	10.167.51.140/30	10.167.51.141 – 10.167.51.142	10.167.51.143
37	10.167.51.144/30	10.167.51.145 – 10.167.51.146	10.167.51.147
38	10.167.51.148/30	10.167.51.149 – 10.167.51.150	10.167.51.151
39	10.167.51.152/30	10.167.51.153 – 10.167.51.154	10.167.51.155
40	10.167.51.156/30	10.167.51.157 – 10.167.51.158	10.167.51.159
41	10.167.51.160/30	10.167.51.161 – 10.167.51.162	10.167.51.163
42	10.167.51.164/30	10.167.51.165 – 10.167.51.166	10.167.51.167
43	10.167.51.168/30	10.167.51.169 – 10.167.51.170	10.167.51.171
44	10.167.51.172/30	10.167.51.173 – 10.167.51.174	10.167.51.175
45	10.167.51.176/30	10.167.51.177 – 10.167.51.178	10.167.51.179
46	10.167.51.180/30	10.167.51.181 – 10.167.51.182	10.167.51.183
47	10.167.51.184/30	10.167.51.185 – 10.167.51.186	10.167.51.187
48	10.167.51.188/30	10.167.51.189 – 10.167.51.190	10.167.51.191
49	10.167.51.192/30	10.167.51.193 – 10.167.51.194	10.167.51.195
50	10.167.51.196/30	10.167.51.197 – 10.167.51.198	10.167.51.199
51	10.167.51.200/30	10.167.51.201 – 10.167.51.202	10.167.51.203
52	10.167.51.204/30	10.167.51.205 – 10.167.51.206	10.167.51.207
53	10.167.51.208/30	10.167.51.209 – 10.167.51.210	10.167.51.211
54	10.167.51.212/30	10.167.51.213 – 10.167.51.214	10.167.51.215
55	10.167.51.216/30	10.167.51.217 – 10.167.51.218	10.167.51.219
56	10.167.51.220/30	10.167.51.221 – 10.167.51.222	10.167.51.223
57	10.167.51.224/30	10.167.51.225 – 10.167.51.226	10.167.51.227
58	10.167.51.228/30	10.167.51.229 – 10.167.51.230	10.167.51.231
59	10.167.51.232/30	10.167.51.233 – 10.167.51.234	10.167.51.235
60	10.167.51.236/30	10.167.51.237 – 10.167.51.238	10.167.51.239
61	10.167.51.240/30	10.167.51.241 – 10.167.51.242	10.167.51.243
62	10.167.51.244/30	10.167.51.245 – 10.167.51.246	10.167.51.247
63	10.167.51.248/30	10.167.51.249 – 10.167.51.250	10.167.51.251
64	10.167.51.252/30	10.167.51.253 – 10.167.51.254	10.167.51.255

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 /24
/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	1
/25	255.255.255.128	128	126	2 split →
/26	255.255.255.192	64	62	4 split →
/27	255.255.255.224	32	30	8 split →
/28	255.255.255.240	16	14	16 split →
/29	255.255.255.248	8	6	32 split →
/30	255.255.255.252	4	2	64 split →
/31	255.255.255.254	2	2	128 split →
/32	255.255.255.255	1	1	256 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 →