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)10.131.23.0/24

network10.131.23.0/24

broadcast10.131.23.255

first host10.131.23.1

last host10.131.23.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.131.23.0/24

address00001010.10000011.00010111.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.10000011.00010111.00000000

broadcast00001010.10000011.00010111.11111111

green = network part, grey = host part

hex0x0a831700

decimal176363264

reverse dns0.23.131.10.in-addr.arpa

ipv4-mapped::ffff:a83:1700

/24 split into /30 · 64 subnets

close ×

#	network	host range	broadcast
1	10.131.23.0/30	10.131.23.1 – 10.131.23.2	10.131.23.3
2	10.131.23.4/30	10.131.23.5 – 10.131.23.6	10.131.23.7
3	10.131.23.8/30	10.131.23.9 – 10.131.23.10	10.131.23.11
4	10.131.23.12/30	10.131.23.13 – 10.131.23.14	10.131.23.15
5	10.131.23.16/30	10.131.23.17 – 10.131.23.18	10.131.23.19
6	10.131.23.20/30	10.131.23.21 – 10.131.23.22	10.131.23.23
7	10.131.23.24/30	10.131.23.25 – 10.131.23.26	10.131.23.27
8	10.131.23.28/30	10.131.23.29 – 10.131.23.30	10.131.23.31
9	10.131.23.32/30	10.131.23.33 – 10.131.23.34	10.131.23.35
10	10.131.23.36/30	10.131.23.37 – 10.131.23.38	10.131.23.39
11	10.131.23.40/30	10.131.23.41 – 10.131.23.42	10.131.23.43
12	10.131.23.44/30	10.131.23.45 – 10.131.23.46	10.131.23.47
13	10.131.23.48/30	10.131.23.49 – 10.131.23.50	10.131.23.51
14	10.131.23.52/30	10.131.23.53 – 10.131.23.54	10.131.23.55
15	10.131.23.56/30	10.131.23.57 – 10.131.23.58	10.131.23.59
16	10.131.23.60/30	10.131.23.61 – 10.131.23.62	10.131.23.63
17	10.131.23.64/30	10.131.23.65 – 10.131.23.66	10.131.23.67
18	10.131.23.68/30	10.131.23.69 – 10.131.23.70	10.131.23.71
19	10.131.23.72/30	10.131.23.73 – 10.131.23.74	10.131.23.75
20	10.131.23.76/30	10.131.23.77 – 10.131.23.78	10.131.23.79
21	10.131.23.80/30	10.131.23.81 – 10.131.23.82	10.131.23.83
22	10.131.23.84/30	10.131.23.85 – 10.131.23.86	10.131.23.87
23	10.131.23.88/30	10.131.23.89 – 10.131.23.90	10.131.23.91
24	10.131.23.92/30	10.131.23.93 – 10.131.23.94	10.131.23.95
25	10.131.23.96/30	10.131.23.97 – 10.131.23.98	10.131.23.99
26	10.131.23.100/30	10.131.23.101 – 10.131.23.102	10.131.23.103
27	10.131.23.104/30	10.131.23.105 – 10.131.23.106	10.131.23.107
28	10.131.23.108/30	10.131.23.109 – 10.131.23.110	10.131.23.111
29	10.131.23.112/30	10.131.23.113 – 10.131.23.114	10.131.23.115
30	10.131.23.116/30	10.131.23.117 – 10.131.23.118	10.131.23.119
31	10.131.23.120/30	10.131.23.121 – 10.131.23.122	10.131.23.123
32	10.131.23.124/30	10.131.23.125 – 10.131.23.126	10.131.23.127
33	10.131.23.128/30	10.131.23.129 – 10.131.23.130	10.131.23.131
34	10.131.23.132/30	10.131.23.133 – 10.131.23.134	10.131.23.135
35	10.131.23.136/30	10.131.23.137 – 10.131.23.138	10.131.23.139
36	10.131.23.140/30	10.131.23.141 – 10.131.23.142	10.131.23.143
37	10.131.23.144/30	10.131.23.145 – 10.131.23.146	10.131.23.147
38	10.131.23.148/30	10.131.23.149 – 10.131.23.150	10.131.23.151
39	10.131.23.152/30	10.131.23.153 – 10.131.23.154	10.131.23.155
40	10.131.23.156/30	10.131.23.157 – 10.131.23.158	10.131.23.159
41	10.131.23.160/30	10.131.23.161 – 10.131.23.162	10.131.23.163
42	10.131.23.164/30	10.131.23.165 – 10.131.23.166	10.131.23.167
43	10.131.23.168/30	10.131.23.169 – 10.131.23.170	10.131.23.171
44	10.131.23.172/30	10.131.23.173 – 10.131.23.174	10.131.23.175
45	10.131.23.176/30	10.131.23.177 – 10.131.23.178	10.131.23.179
46	10.131.23.180/30	10.131.23.181 – 10.131.23.182	10.131.23.183
47	10.131.23.184/30	10.131.23.185 – 10.131.23.186	10.131.23.187
48	10.131.23.188/30	10.131.23.189 – 10.131.23.190	10.131.23.191
49	10.131.23.192/30	10.131.23.193 – 10.131.23.194	10.131.23.195
50	10.131.23.196/30	10.131.23.197 – 10.131.23.198	10.131.23.199
51	10.131.23.200/30	10.131.23.201 – 10.131.23.202	10.131.23.203
52	10.131.23.204/30	10.131.23.205 – 10.131.23.206	10.131.23.207
53	10.131.23.208/30	10.131.23.209 – 10.131.23.210	10.131.23.211
54	10.131.23.212/30	10.131.23.213 – 10.131.23.214	10.131.23.215
55	10.131.23.216/30	10.131.23.217 – 10.131.23.218	10.131.23.219
56	10.131.23.220/30	10.131.23.221 – 10.131.23.222	10.131.23.223
57	10.131.23.224/30	10.131.23.225 – 10.131.23.226	10.131.23.227
58	10.131.23.228/30	10.131.23.229 – 10.131.23.230	10.131.23.231
59	10.131.23.232/30	10.131.23.233 – 10.131.23.234	10.131.23.235
60	10.131.23.236/30	10.131.23.237 – 10.131.23.238	10.131.23.239
61	10.131.23.240/30	10.131.23.241 – 10.131.23.242	10.131.23.243
62	10.131.23.244/30	10.131.23.245 – 10.131.23.246	10.131.23.247
63	10.131.23.248/30	10.131.23.249 – 10.131.23.250	10.131.23.251
64	10.131.23.252/30	10.131.23.253 – 10.131.23.254	10.131.23.255

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 →