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)10.2.157.0/24

network10.2.157.0/24

broadcast10.2.157.255

first host10.2.157.1

last host10.2.157.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.2.157.0/24

address00001010.00000010.10011101.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.00000010.10011101.00000000

broadcast00001010.00000010.10011101.11111111

green = network part, grey = host part

hex0x0a029d00

decimal167943424

reverse dns0.157.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:9d00

/24 split into /30 · 64 subnets

close ×

#	network	host range	broadcast
1	10.2.157.0/30	10.2.157.1 – 10.2.157.2	10.2.157.3
2	10.2.157.4/30	10.2.157.5 – 10.2.157.6	10.2.157.7
3	10.2.157.8/30	10.2.157.9 – 10.2.157.10	10.2.157.11
4	10.2.157.12/30	10.2.157.13 – 10.2.157.14	10.2.157.15
5	10.2.157.16/30	10.2.157.17 – 10.2.157.18	10.2.157.19
6	10.2.157.20/30	10.2.157.21 – 10.2.157.22	10.2.157.23
7	10.2.157.24/30	10.2.157.25 – 10.2.157.26	10.2.157.27
8	10.2.157.28/30	10.2.157.29 – 10.2.157.30	10.2.157.31
9	10.2.157.32/30	10.2.157.33 – 10.2.157.34	10.2.157.35
10	10.2.157.36/30	10.2.157.37 – 10.2.157.38	10.2.157.39
11	10.2.157.40/30	10.2.157.41 – 10.2.157.42	10.2.157.43
12	10.2.157.44/30	10.2.157.45 – 10.2.157.46	10.2.157.47
13	10.2.157.48/30	10.2.157.49 – 10.2.157.50	10.2.157.51
14	10.2.157.52/30	10.2.157.53 – 10.2.157.54	10.2.157.55
15	10.2.157.56/30	10.2.157.57 – 10.2.157.58	10.2.157.59
16	10.2.157.60/30	10.2.157.61 – 10.2.157.62	10.2.157.63
17	10.2.157.64/30	10.2.157.65 – 10.2.157.66	10.2.157.67
18	10.2.157.68/30	10.2.157.69 – 10.2.157.70	10.2.157.71
19	10.2.157.72/30	10.2.157.73 – 10.2.157.74	10.2.157.75
20	10.2.157.76/30	10.2.157.77 – 10.2.157.78	10.2.157.79
21	10.2.157.80/30	10.2.157.81 – 10.2.157.82	10.2.157.83
22	10.2.157.84/30	10.2.157.85 – 10.2.157.86	10.2.157.87
23	10.2.157.88/30	10.2.157.89 – 10.2.157.90	10.2.157.91
24	10.2.157.92/30	10.2.157.93 – 10.2.157.94	10.2.157.95
25	10.2.157.96/30	10.2.157.97 – 10.2.157.98	10.2.157.99
26	10.2.157.100/30	10.2.157.101 – 10.2.157.102	10.2.157.103
27	10.2.157.104/30	10.2.157.105 – 10.2.157.106	10.2.157.107
28	10.2.157.108/30	10.2.157.109 – 10.2.157.110	10.2.157.111
29	10.2.157.112/30	10.2.157.113 – 10.2.157.114	10.2.157.115
30	10.2.157.116/30	10.2.157.117 – 10.2.157.118	10.2.157.119
31	10.2.157.120/30	10.2.157.121 – 10.2.157.122	10.2.157.123
32	10.2.157.124/30	10.2.157.125 – 10.2.157.126	10.2.157.127
33	10.2.157.128/30	10.2.157.129 – 10.2.157.130	10.2.157.131
34	10.2.157.132/30	10.2.157.133 – 10.2.157.134	10.2.157.135
35	10.2.157.136/30	10.2.157.137 – 10.2.157.138	10.2.157.139
36	10.2.157.140/30	10.2.157.141 – 10.2.157.142	10.2.157.143
37	10.2.157.144/30	10.2.157.145 – 10.2.157.146	10.2.157.147
38	10.2.157.148/30	10.2.157.149 – 10.2.157.150	10.2.157.151
39	10.2.157.152/30	10.2.157.153 – 10.2.157.154	10.2.157.155
40	10.2.157.156/30	10.2.157.157 – 10.2.157.158	10.2.157.159
41	10.2.157.160/30	10.2.157.161 – 10.2.157.162	10.2.157.163
42	10.2.157.164/30	10.2.157.165 – 10.2.157.166	10.2.157.167
43	10.2.157.168/30	10.2.157.169 – 10.2.157.170	10.2.157.171
44	10.2.157.172/30	10.2.157.173 – 10.2.157.174	10.2.157.175
45	10.2.157.176/30	10.2.157.177 – 10.2.157.178	10.2.157.179
46	10.2.157.180/30	10.2.157.181 – 10.2.157.182	10.2.157.183
47	10.2.157.184/30	10.2.157.185 – 10.2.157.186	10.2.157.187
48	10.2.157.188/30	10.2.157.189 – 10.2.157.190	10.2.157.191
49	10.2.157.192/30	10.2.157.193 – 10.2.157.194	10.2.157.195
50	10.2.157.196/30	10.2.157.197 – 10.2.157.198	10.2.157.199
51	10.2.157.200/30	10.2.157.201 – 10.2.157.202	10.2.157.203
52	10.2.157.204/30	10.2.157.205 – 10.2.157.206	10.2.157.207
53	10.2.157.208/30	10.2.157.209 – 10.2.157.210	10.2.157.211
54	10.2.157.212/30	10.2.157.213 – 10.2.157.214	10.2.157.215
55	10.2.157.216/30	10.2.157.217 – 10.2.157.218	10.2.157.219
56	10.2.157.220/30	10.2.157.221 – 10.2.157.222	10.2.157.223
57	10.2.157.224/30	10.2.157.225 – 10.2.157.226	10.2.157.227
58	10.2.157.228/30	10.2.157.229 – 10.2.157.230	10.2.157.231
59	10.2.157.232/30	10.2.157.233 – 10.2.157.234	10.2.157.235
60	10.2.157.236/30	10.2.157.237 – 10.2.157.238	10.2.157.239
61	10.2.157.240/30	10.2.157.241 – 10.2.157.242	10.2.157.243
62	10.2.157.244/30	10.2.157.245 – 10.2.157.246	10.2.157.247
63	10.2.157.248/30	10.2.157.249 – 10.2.157.250	10.2.157.251
64	10.2.157.252/30	10.2.157.253 – 10.2.157.254	10.2.157.255

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 →