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)10.2.155.0/24

network10.2.155.0/24

broadcast10.2.155.255

first host10.2.155.1

last host10.2.155.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.2.155.0/24

address00001010.00000010.10011011.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.00000010.10011011.00000000

broadcast00001010.00000010.10011011.11111111

green = network part, grey = host part

hex0x0a029b00

decimal167942912

reverse dns0.155.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:9b00

/24 split into /30 · 64 subnets

close ×

#	network	host range	broadcast
1	10.2.155.0/30	10.2.155.1 – 10.2.155.2	10.2.155.3
2	10.2.155.4/30	10.2.155.5 – 10.2.155.6	10.2.155.7
3	10.2.155.8/30	10.2.155.9 – 10.2.155.10	10.2.155.11
4	10.2.155.12/30	10.2.155.13 – 10.2.155.14	10.2.155.15
5	10.2.155.16/30	10.2.155.17 – 10.2.155.18	10.2.155.19
6	10.2.155.20/30	10.2.155.21 – 10.2.155.22	10.2.155.23
7	10.2.155.24/30	10.2.155.25 – 10.2.155.26	10.2.155.27
8	10.2.155.28/30	10.2.155.29 – 10.2.155.30	10.2.155.31
9	10.2.155.32/30	10.2.155.33 – 10.2.155.34	10.2.155.35
10	10.2.155.36/30	10.2.155.37 – 10.2.155.38	10.2.155.39
11	10.2.155.40/30	10.2.155.41 – 10.2.155.42	10.2.155.43
12	10.2.155.44/30	10.2.155.45 – 10.2.155.46	10.2.155.47
13	10.2.155.48/30	10.2.155.49 – 10.2.155.50	10.2.155.51
14	10.2.155.52/30	10.2.155.53 – 10.2.155.54	10.2.155.55
15	10.2.155.56/30	10.2.155.57 – 10.2.155.58	10.2.155.59
16	10.2.155.60/30	10.2.155.61 – 10.2.155.62	10.2.155.63
17	10.2.155.64/30	10.2.155.65 – 10.2.155.66	10.2.155.67
18	10.2.155.68/30	10.2.155.69 – 10.2.155.70	10.2.155.71
19	10.2.155.72/30	10.2.155.73 – 10.2.155.74	10.2.155.75
20	10.2.155.76/30	10.2.155.77 – 10.2.155.78	10.2.155.79
21	10.2.155.80/30	10.2.155.81 – 10.2.155.82	10.2.155.83
22	10.2.155.84/30	10.2.155.85 – 10.2.155.86	10.2.155.87
23	10.2.155.88/30	10.2.155.89 – 10.2.155.90	10.2.155.91
24	10.2.155.92/30	10.2.155.93 – 10.2.155.94	10.2.155.95
25	10.2.155.96/30	10.2.155.97 – 10.2.155.98	10.2.155.99
26	10.2.155.100/30	10.2.155.101 – 10.2.155.102	10.2.155.103
27	10.2.155.104/30	10.2.155.105 – 10.2.155.106	10.2.155.107
28	10.2.155.108/30	10.2.155.109 – 10.2.155.110	10.2.155.111
29	10.2.155.112/30	10.2.155.113 – 10.2.155.114	10.2.155.115
30	10.2.155.116/30	10.2.155.117 – 10.2.155.118	10.2.155.119
31	10.2.155.120/30	10.2.155.121 – 10.2.155.122	10.2.155.123
32	10.2.155.124/30	10.2.155.125 – 10.2.155.126	10.2.155.127
33	10.2.155.128/30	10.2.155.129 – 10.2.155.130	10.2.155.131
34	10.2.155.132/30	10.2.155.133 – 10.2.155.134	10.2.155.135
35	10.2.155.136/30	10.2.155.137 – 10.2.155.138	10.2.155.139
36	10.2.155.140/30	10.2.155.141 – 10.2.155.142	10.2.155.143
37	10.2.155.144/30	10.2.155.145 – 10.2.155.146	10.2.155.147
38	10.2.155.148/30	10.2.155.149 – 10.2.155.150	10.2.155.151
39	10.2.155.152/30	10.2.155.153 – 10.2.155.154	10.2.155.155
40	10.2.155.156/30	10.2.155.157 – 10.2.155.158	10.2.155.159
41	10.2.155.160/30	10.2.155.161 – 10.2.155.162	10.2.155.163
42	10.2.155.164/30	10.2.155.165 – 10.2.155.166	10.2.155.167
43	10.2.155.168/30	10.2.155.169 – 10.2.155.170	10.2.155.171
44	10.2.155.172/30	10.2.155.173 – 10.2.155.174	10.2.155.175
45	10.2.155.176/30	10.2.155.177 – 10.2.155.178	10.2.155.179
46	10.2.155.180/30	10.2.155.181 – 10.2.155.182	10.2.155.183
47	10.2.155.184/30	10.2.155.185 – 10.2.155.186	10.2.155.187
48	10.2.155.188/30	10.2.155.189 – 10.2.155.190	10.2.155.191
49	10.2.155.192/30	10.2.155.193 – 10.2.155.194	10.2.155.195
50	10.2.155.196/30	10.2.155.197 – 10.2.155.198	10.2.155.199
51	10.2.155.200/30	10.2.155.201 – 10.2.155.202	10.2.155.203
52	10.2.155.204/30	10.2.155.205 – 10.2.155.206	10.2.155.207
53	10.2.155.208/30	10.2.155.209 – 10.2.155.210	10.2.155.211
54	10.2.155.212/30	10.2.155.213 – 10.2.155.214	10.2.155.215
55	10.2.155.216/30	10.2.155.217 – 10.2.155.218	10.2.155.219
56	10.2.155.220/30	10.2.155.221 – 10.2.155.222	10.2.155.223
57	10.2.155.224/30	10.2.155.225 – 10.2.155.226	10.2.155.227
58	10.2.155.228/30	10.2.155.229 – 10.2.155.230	10.2.155.231
59	10.2.155.232/30	10.2.155.233 – 10.2.155.234	10.2.155.235
60	10.2.155.236/30	10.2.155.237 – 10.2.155.238	10.2.155.239
61	10.2.155.240/30	10.2.155.241 – 10.2.155.242	10.2.155.243
62	10.2.155.244/30	10.2.155.245 – 10.2.155.246	10.2.155.247
63	10.2.155.248/30	10.2.155.249 – 10.2.155.250	10.2.155.251
64	10.2.155.252/30	10.2.155.253 – 10.2.155.254	10.2.155.255

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 →