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)10.131.209.0/24

network10.131.209.0/24

broadcast10.131.209.255

first host10.131.209.1

last host10.131.209.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.131.209.0/24

address00001010.10000011.11010001.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.10000011.11010001.00000000

broadcast00001010.10000011.11010001.11111111

green = network part, grey = host part

hex0x0a83d100

decimal176410880

reverse dns0.209.131.10.in-addr.arpa

ipv4-mapped::ffff:a83:d100

/24 split into /30 · 64 subnets

close ×

#	network	host range	broadcast
1	10.131.209.0/30	10.131.209.1 – 10.131.209.2	10.131.209.3
2	10.131.209.4/30	10.131.209.5 – 10.131.209.6	10.131.209.7
3	10.131.209.8/30	10.131.209.9 – 10.131.209.10	10.131.209.11
4	10.131.209.12/30	10.131.209.13 – 10.131.209.14	10.131.209.15
5	10.131.209.16/30	10.131.209.17 – 10.131.209.18	10.131.209.19
6	10.131.209.20/30	10.131.209.21 – 10.131.209.22	10.131.209.23
7	10.131.209.24/30	10.131.209.25 – 10.131.209.26	10.131.209.27
8	10.131.209.28/30	10.131.209.29 – 10.131.209.30	10.131.209.31
9	10.131.209.32/30	10.131.209.33 – 10.131.209.34	10.131.209.35
10	10.131.209.36/30	10.131.209.37 – 10.131.209.38	10.131.209.39
11	10.131.209.40/30	10.131.209.41 – 10.131.209.42	10.131.209.43
12	10.131.209.44/30	10.131.209.45 – 10.131.209.46	10.131.209.47
13	10.131.209.48/30	10.131.209.49 – 10.131.209.50	10.131.209.51
14	10.131.209.52/30	10.131.209.53 – 10.131.209.54	10.131.209.55
15	10.131.209.56/30	10.131.209.57 – 10.131.209.58	10.131.209.59
16	10.131.209.60/30	10.131.209.61 – 10.131.209.62	10.131.209.63
17	10.131.209.64/30	10.131.209.65 – 10.131.209.66	10.131.209.67
18	10.131.209.68/30	10.131.209.69 – 10.131.209.70	10.131.209.71
19	10.131.209.72/30	10.131.209.73 – 10.131.209.74	10.131.209.75
20	10.131.209.76/30	10.131.209.77 – 10.131.209.78	10.131.209.79
21	10.131.209.80/30	10.131.209.81 – 10.131.209.82	10.131.209.83
22	10.131.209.84/30	10.131.209.85 – 10.131.209.86	10.131.209.87
23	10.131.209.88/30	10.131.209.89 – 10.131.209.90	10.131.209.91
24	10.131.209.92/30	10.131.209.93 – 10.131.209.94	10.131.209.95
25	10.131.209.96/30	10.131.209.97 – 10.131.209.98	10.131.209.99
26	10.131.209.100/30	10.131.209.101 – 10.131.209.102	10.131.209.103
27	10.131.209.104/30	10.131.209.105 – 10.131.209.106	10.131.209.107
28	10.131.209.108/30	10.131.209.109 – 10.131.209.110	10.131.209.111
29	10.131.209.112/30	10.131.209.113 – 10.131.209.114	10.131.209.115
30	10.131.209.116/30	10.131.209.117 – 10.131.209.118	10.131.209.119
31	10.131.209.120/30	10.131.209.121 – 10.131.209.122	10.131.209.123
32	10.131.209.124/30	10.131.209.125 – 10.131.209.126	10.131.209.127
33	10.131.209.128/30	10.131.209.129 – 10.131.209.130	10.131.209.131
34	10.131.209.132/30	10.131.209.133 – 10.131.209.134	10.131.209.135
35	10.131.209.136/30	10.131.209.137 – 10.131.209.138	10.131.209.139
36	10.131.209.140/30	10.131.209.141 – 10.131.209.142	10.131.209.143
37	10.131.209.144/30	10.131.209.145 – 10.131.209.146	10.131.209.147
38	10.131.209.148/30	10.131.209.149 – 10.131.209.150	10.131.209.151
39	10.131.209.152/30	10.131.209.153 – 10.131.209.154	10.131.209.155
40	10.131.209.156/30	10.131.209.157 – 10.131.209.158	10.131.209.159
41	10.131.209.160/30	10.131.209.161 – 10.131.209.162	10.131.209.163
42	10.131.209.164/30	10.131.209.165 – 10.131.209.166	10.131.209.167
43	10.131.209.168/30	10.131.209.169 – 10.131.209.170	10.131.209.171
44	10.131.209.172/30	10.131.209.173 – 10.131.209.174	10.131.209.175
45	10.131.209.176/30	10.131.209.177 – 10.131.209.178	10.131.209.179
46	10.131.209.180/30	10.131.209.181 – 10.131.209.182	10.131.209.183
47	10.131.209.184/30	10.131.209.185 – 10.131.209.186	10.131.209.187
48	10.131.209.188/30	10.131.209.189 – 10.131.209.190	10.131.209.191
49	10.131.209.192/30	10.131.209.193 – 10.131.209.194	10.131.209.195
50	10.131.209.196/30	10.131.209.197 – 10.131.209.198	10.131.209.199
51	10.131.209.200/30	10.131.209.201 – 10.131.209.202	10.131.209.203
52	10.131.209.204/30	10.131.209.205 – 10.131.209.206	10.131.209.207
53	10.131.209.208/30	10.131.209.209 – 10.131.209.210	10.131.209.211
54	10.131.209.212/30	10.131.209.213 – 10.131.209.214	10.131.209.215
55	10.131.209.216/30	10.131.209.217 – 10.131.209.218	10.131.209.219
56	10.131.209.220/30	10.131.209.221 – 10.131.209.222	10.131.209.223
57	10.131.209.224/30	10.131.209.225 – 10.131.209.226	10.131.209.227
58	10.131.209.228/30	10.131.209.229 – 10.131.209.230	10.131.209.231
59	10.131.209.232/30	10.131.209.233 – 10.131.209.234	10.131.209.235
60	10.131.209.236/30	10.131.209.237 – 10.131.209.238	10.131.209.239
61	10.131.209.240/30	10.131.209.241 – 10.131.209.242	10.131.209.243
62	10.131.209.244/30	10.131.209.245 – 10.131.209.246	10.131.209.247
63	10.131.209.248/30	10.131.209.249 – 10.131.209.250	10.131.209.251
64	10.131.209.252/30	10.131.209.253 – 10.131.209.254	10.131.209.255

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 →