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)10.2.151.0/24

network10.2.151.0/24

broadcast10.2.151.255

first host10.2.151.1

last host10.2.151.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.2.151.0/24

address00001010.00000010.10010111.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.00000010.10010111.00000000

broadcast00001010.00000010.10010111.11111111

green = network part, grey = host part

hex0x0a029700

decimal167941888

reverse dns0.151.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:9700

/24 split into /30 · 64 subnets

close ×

#	network	host range	broadcast
1	10.2.151.0/30	10.2.151.1 – 10.2.151.2	10.2.151.3
2	10.2.151.4/30	10.2.151.5 – 10.2.151.6	10.2.151.7
3	10.2.151.8/30	10.2.151.9 – 10.2.151.10	10.2.151.11
4	10.2.151.12/30	10.2.151.13 – 10.2.151.14	10.2.151.15
5	10.2.151.16/30	10.2.151.17 – 10.2.151.18	10.2.151.19
6	10.2.151.20/30	10.2.151.21 – 10.2.151.22	10.2.151.23
7	10.2.151.24/30	10.2.151.25 – 10.2.151.26	10.2.151.27
8	10.2.151.28/30	10.2.151.29 – 10.2.151.30	10.2.151.31
9	10.2.151.32/30	10.2.151.33 – 10.2.151.34	10.2.151.35
10	10.2.151.36/30	10.2.151.37 – 10.2.151.38	10.2.151.39
11	10.2.151.40/30	10.2.151.41 – 10.2.151.42	10.2.151.43
12	10.2.151.44/30	10.2.151.45 – 10.2.151.46	10.2.151.47
13	10.2.151.48/30	10.2.151.49 – 10.2.151.50	10.2.151.51
14	10.2.151.52/30	10.2.151.53 – 10.2.151.54	10.2.151.55
15	10.2.151.56/30	10.2.151.57 – 10.2.151.58	10.2.151.59
16	10.2.151.60/30	10.2.151.61 – 10.2.151.62	10.2.151.63
17	10.2.151.64/30	10.2.151.65 – 10.2.151.66	10.2.151.67
18	10.2.151.68/30	10.2.151.69 – 10.2.151.70	10.2.151.71
19	10.2.151.72/30	10.2.151.73 – 10.2.151.74	10.2.151.75
20	10.2.151.76/30	10.2.151.77 – 10.2.151.78	10.2.151.79
21	10.2.151.80/30	10.2.151.81 – 10.2.151.82	10.2.151.83
22	10.2.151.84/30	10.2.151.85 – 10.2.151.86	10.2.151.87
23	10.2.151.88/30	10.2.151.89 – 10.2.151.90	10.2.151.91
24	10.2.151.92/30	10.2.151.93 – 10.2.151.94	10.2.151.95
25	10.2.151.96/30	10.2.151.97 – 10.2.151.98	10.2.151.99
26	10.2.151.100/30	10.2.151.101 – 10.2.151.102	10.2.151.103
27	10.2.151.104/30	10.2.151.105 – 10.2.151.106	10.2.151.107
28	10.2.151.108/30	10.2.151.109 – 10.2.151.110	10.2.151.111
29	10.2.151.112/30	10.2.151.113 – 10.2.151.114	10.2.151.115
30	10.2.151.116/30	10.2.151.117 – 10.2.151.118	10.2.151.119
31	10.2.151.120/30	10.2.151.121 – 10.2.151.122	10.2.151.123
32	10.2.151.124/30	10.2.151.125 – 10.2.151.126	10.2.151.127
33	10.2.151.128/30	10.2.151.129 – 10.2.151.130	10.2.151.131
34	10.2.151.132/30	10.2.151.133 – 10.2.151.134	10.2.151.135
35	10.2.151.136/30	10.2.151.137 – 10.2.151.138	10.2.151.139
36	10.2.151.140/30	10.2.151.141 – 10.2.151.142	10.2.151.143
37	10.2.151.144/30	10.2.151.145 – 10.2.151.146	10.2.151.147
38	10.2.151.148/30	10.2.151.149 – 10.2.151.150	10.2.151.151
39	10.2.151.152/30	10.2.151.153 – 10.2.151.154	10.2.151.155
40	10.2.151.156/30	10.2.151.157 – 10.2.151.158	10.2.151.159
41	10.2.151.160/30	10.2.151.161 – 10.2.151.162	10.2.151.163
42	10.2.151.164/30	10.2.151.165 – 10.2.151.166	10.2.151.167
43	10.2.151.168/30	10.2.151.169 – 10.2.151.170	10.2.151.171
44	10.2.151.172/30	10.2.151.173 – 10.2.151.174	10.2.151.175
45	10.2.151.176/30	10.2.151.177 – 10.2.151.178	10.2.151.179
46	10.2.151.180/30	10.2.151.181 – 10.2.151.182	10.2.151.183
47	10.2.151.184/30	10.2.151.185 – 10.2.151.186	10.2.151.187
48	10.2.151.188/30	10.2.151.189 – 10.2.151.190	10.2.151.191
49	10.2.151.192/30	10.2.151.193 – 10.2.151.194	10.2.151.195
50	10.2.151.196/30	10.2.151.197 – 10.2.151.198	10.2.151.199
51	10.2.151.200/30	10.2.151.201 – 10.2.151.202	10.2.151.203
52	10.2.151.204/30	10.2.151.205 – 10.2.151.206	10.2.151.207
53	10.2.151.208/30	10.2.151.209 – 10.2.151.210	10.2.151.211
54	10.2.151.212/30	10.2.151.213 – 10.2.151.214	10.2.151.215
55	10.2.151.216/30	10.2.151.217 – 10.2.151.218	10.2.151.219
56	10.2.151.220/30	10.2.151.221 – 10.2.151.222	10.2.151.223
57	10.2.151.224/30	10.2.151.225 – 10.2.151.226	10.2.151.227
58	10.2.151.228/30	10.2.151.229 – 10.2.151.230	10.2.151.231
59	10.2.151.232/30	10.2.151.233 – 10.2.151.234	10.2.151.235
60	10.2.151.236/30	10.2.151.237 – 10.2.151.238	10.2.151.239
61	10.2.151.240/30	10.2.151.241 – 10.2.151.242	10.2.151.243
62	10.2.151.244/30	10.2.151.245 – 10.2.151.246	10.2.151.247
63	10.2.151.248/30	10.2.151.249 – 10.2.151.250	10.2.151.251
64	10.2.151.252/30	10.2.151.253 – 10.2.151.254	10.2.151.255

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 →