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)172.16.2.0/24

network172.16.2.0/24

broadcast172.16.2.255

first host172.16.2.1

last host172.16.2.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classB

ipcalc 172.16.2.0/24

address10101100.00010000.00000010.00000000

subnet mask11111111.11111111.11111111.00000000

network10101100.00010000.00000010.00000000

broadcast10101100.00010000.00000010.11111111

green = network part, grey = host part

hex0xac100200

decimal2886730240

reverse dns0.2.16.172.in-addr.arpa

ipv4-mapped::ffff:ac10:200

/24 split into /30 · 64 subnets

close ×

#	network	host range	broadcast
1	172.16.2.0/30	172.16.2.1 – 172.16.2.2	172.16.2.3
2	172.16.2.4/30	172.16.2.5 – 172.16.2.6	172.16.2.7
3	172.16.2.8/30	172.16.2.9 – 172.16.2.10	172.16.2.11
4	172.16.2.12/30	172.16.2.13 – 172.16.2.14	172.16.2.15
5	172.16.2.16/30	172.16.2.17 – 172.16.2.18	172.16.2.19
6	172.16.2.20/30	172.16.2.21 – 172.16.2.22	172.16.2.23
7	172.16.2.24/30	172.16.2.25 – 172.16.2.26	172.16.2.27
8	172.16.2.28/30	172.16.2.29 – 172.16.2.30	172.16.2.31
9	172.16.2.32/30	172.16.2.33 – 172.16.2.34	172.16.2.35
10	172.16.2.36/30	172.16.2.37 – 172.16.2.38	172.16.2.39
11	172.16.2.40/30	172.16.2.41 – 172.16.2.42	172.16.2.43
12	172.16.2.44/30	172.16.2.45 – 172.16.2.46	172.16.2.47
13	172.16.2.48/30	172.16.2.49 – 172.16.2.50	172.16.2.51
14	172.16.2.52/30	172.16.2.53 – 172.16.2.54	172.16.2.55
15	172.16.2.56/30	172.16.2.57 – 172.16.2.58	172.16.2.59
16	172.16.2.60/30	172.16.2.61 – 172.16.2.62	172.16.2.63
17	172.16.2.64/30	172.16.2.65 – 172.16.2.66	172.16.2.67
18	172.16.2.68/30	172.16.2.69 – 172.16.2.70	172.16.2.71
19	172.16.2.72/30	172.16.2.73 – 172.16.2.74	172.16.2.75
20	172.16.2.76/30	172.16.2.77 – 172.16.2.78	172.16.2.79
21	172.16.2.80/30	172.16.2.81 – 172.16.2.82	172.16.2.83
22	172.16.2.84/30	172.16.2.85 – 172.16.2.86	172.16.2.87
23	172.16.2.88/30	172.16.2.89 – 172.16.2.90	172.16.2.91
24	172.16.2.92/30	172.16.2.93 – 172.16.2.94	172.16.2.95
25	172.16.2.96/30	172.16.2.97 – 172.16.2.98	172.16.2.99
26	172.16.2.100/30	172.16.2.101 – 172.16.2.102	172.16.2.103
27	172.16.2.104/30	172.16.2.105 – 172.16.2.106	172.16.2.107
28	172.16.2.108/30	172.16.2.109 – 172.16.2.110	172.16.2.111
29	172.16.2.112/30	172.16.2.113 – 172.16.2.114	172.16.2.115
30	172.16.2.116/30	172.16.2.117 – 172.16.2.118	172.16.2.119
31	172.16.2.120/30	172.16.2.121 – 172.16.2.122	172.16.2.123
32	172.16.2.124/30	172.16.2.125 – 172.16.2.126	172.16.2.127
33	172.16.2.128/30	172.16.2.129 – 172.16.2.130	172.16.2.131
34	172.16.2.132/30	172.16.2.133 – 172.16.2.134	172.16.2.135
35	172.16.2.136/30	172.16.2.137 – 172.16.2.138	172.16.2.139
36	172.16.2.140/30	172.16.2.141 – 172.16.2.142	172.16.2.143
37	172.16.2.144/30	172.16.2.145 – 172.16.2.146	172.16.2.147
38	172.16.2.148/30	172.16.2.149 – 172.16.2.150	172.16.2.151
39	172.16.2.152/30	172.16.2.153 – 172.16.2.154	172.16.2.155
40	172.16.2.156/30	172.16.2.157 – 172.16.2.158	172.16.2.159
41	172.16.2.160/30	172.16.2.161 – 172.16.2.162	172.16.2.163
42	172.16.2.164/30	172.16.2.165 – 172.16.2.166	172.16.2.167
43	172.16.2.168/30	172.16.2.169 – 172.16.2.170	172.16.2.171
44	172.16.2.172/30	172.16.2.173 – 172.16.2.174	172.16.2.175
45	172.16.2.176/30	172.16.2.177 – 172.16.2.178	172.16.2.179
46	172.16.2.180/30	172.16.2.181 – 172.16.2.182	172.16.2.183
47	172.16.2.184/30	172.16.2.185 – 172.16.2.186	172.16.2.187
48	172.16.2.188/30	172.16.2.189 – 172.16.2.190	172.16.2.191
49	172.16.2.192/30	172.16.2.193 – 172.16.2.194	172.16.2.195
50	172.16.2.196/30	172.16.2.197 – 172.16.2.198	172.16.2.199
51	172.16.2.200/30	172.16.2.201 – 172.16.2.202	172.16.2.203
52	172.16.2.204/30	172.16.2.205 – 172.16.2.206	172.16.2.207
53	172.16.2.208/30	172.16.2.209 – 172.16.2.210	172.16.2.211
54	172.16.2.212/30	172.16.2.213 – 172.16.2.214	172.16.2.215
55	172.16.2.216/30	172.16.2.217 – 172.16.2.218	172.16.2.219
56	172.16.2.220/30	172.16.2.221 – 172.16.2.222	172.16.2.223
57	172.16.2.224/30	172.16.2.225 – 172.16.2.226	172.16.2.227
58	172.16.2.228/30	172.16.2.229 – 172.16.2.230	172.16.2.231
59	172.16.2.232/30	172.16.2.233 – 172.16.2.234	172.16.2.235
60	172.16.2.236/30	172.16.2.237 – 172.16.2.238	172.16.2.239
61	172.16.2.240/30	172.16.2.241 – 172.16.2.242	172.16.2.243
62	172.16.2.244/30	172.16.2.245 – 172.16.2.246	172.16.2.247
63	172.16.2.248/30	172.16.2.249 – 172.16.2.250	172.16.2.251
64	172.16.2.252/30	172.16.2.253 – 172.16.2.254	172.16.2.255

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 →