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)10.2.171.0/24

network10.2.171.0/24

broadcast10.2.171.255

first host10.2.171.1

last host10.2.171.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.2.171.0/24

address00001010.00000010.10101011.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.00000010.10101011.00000000

broadcast00001010.00000010.10101011.11111111

green = network part, grey = host part

hex0x0a02ab00

decimal167947008

reverse dns0.171.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:ab00

/24 split into /30 · 64 subnets

close ×

#	network	host range	broadcast
1	10.2.171.0/30	10.2.171.1 – 10.2.171.2	10.2.171.3
2	10.2.171.4/30	10.2.171.5 – 10.2.171.6	10.2.171.7
3	10.2.171.8/30	10.2.171.9 – 10.2.171.10	10.2.171.11
4	10.2.171.12/30	10.2.171.13 – 10.2.171.14	10.2.171.15
5	10.2.171.16/30	10.2.171.17 – 10.2.171.18	10.2.171.19
6	10.2.171.20/30	10.2.171.21 – 10.2.171.22	10.2.171.23
7	10.2.171.24/30	10.2.171.25 – 10.2.171.26	10.2.171.27
8	10.2.171.28/30	10.2.171.29 – 10.2.171.30	10.2.171.31
9	10.2.171.32/30	10.2.171.33 – 10.2.171.34	10.2.171.35
10	10.2.171.36/30	10.2.171.37 – 10.2.171.38	10.2.171.39
11	10.2.171.40/30	10.2.171.41 – 10.2.171.42	10.2.171.43
12	10.2.171.44/30	10.2.171.45 – 10.2.171.46	10.2.171.47
13	10.2.171.48/30	10.2.171.49 – 10.2.171.50	10.2.171.51
14	10.2.171.52/30	10.2.171.53 – 10.2.171.54	10.2.171.55
15	10.2.171.56/30	10.2.171.57 – 10.2.171.58	10.2.171.59
16	10.2.171.60/30	10.2.171.61 – 10.2.171.62	10.2.171.63
17	10.2.171.64/30	10.2.171.65 – 10.2.171.66	10.2.171.67
18	10.2.171.68/30	10.2.171.69 – 10.2.171.70	10.2.171.71
19	10.2.171.72/30	10.2.171.73 – 10.2.171.74	10.2.171.75
20	10.2.171.76/30	10.2.171.77 – 10.2.171.78	10.2.171.79
21	10.2.171.80/30	10.2.171.81 – 10.2.171.82	10.2.171.83
22	10.2.171.84/30	10.2.171.85 – 10.2.171.86	10.2.171.87
23	10.2.171.88/30	10.2.171.89 – 10.2.171.90	10.2.171.91
24	10.2.171.92/30	10.2.171.93 – 10.2.171.94	10.2.171.95
25	10.2.171.96/30	10.2.171.97 – 10.2.171.98	10.2.171.99
26	10.2.171.100/30	10.2.171.101 – 10.2.171.102	10.2.171.103
27	10.2.171.104/30	10.2.171.105 – 10.2.171.106	10.2.171.107
28	10.2.171.108/30	10.2.171.109 – 10.2.171.110	10.2.171.111
29	10.2.171.112/30	10.2.171.113 – 10.2.171.114	10.2.171.115
30	10.2.171.116/30	10.2.171.117 – 10.2.171.118	10.2.171.119
31	10.2.171.120/30	10.2.171.121 – 10.2.171.122	10.2.171.123
32	10.2.171.124/30	10.2.171.125 – 10.2.171.126	10.2.171.127
33	10.2.171.128/30	10.2.171.129 – 10.2.171.130	10.2.171.131
34	10.2.171.132/30	10.2.171.133 – 10.2.171.134	10.2.171.135
35	10.2.171.136/30	10.2.171.137 – 10.2.171.138	10.2.171.139
36	10.2.171.140/30	10.2.171.141 – 10.2.171.142	10.2.171.143
37	10.2.171.144/30	10.2.171.145 – 10.2.171.146	10.2.171.147
38	10.2.171.148/30	10.2.171.149 – 10.2.171.150	10.2.171.151
39	10.2.171.152/30	10.2.171.153 – 10.2.171.154	10.2.171.155
40	10.2.171.156/30	10.2.171.157 – 10.2.171.158	10.2.171.159
41	10.2.171.160/30	10.2.171.161 – 10.2.171.162	10.2.171.163
42	10.2.171.164/30	10.2.171.165 – 10.2.171.166	10.2.171.167
43	10.2.171.168/30	10.2.171.169 – 10.2.171.170	10.2.171.171
44	10.2.171.172/30	10.2.171.173 – 10.2.171.174	10.2.171.175
45	10.2.171.176/30	10.2.171.177 – 10.2.171.178	10.2.171.179
46	10.2.171.180/30	10.2.171.181 – 10.2.171.182	10.2.171.183
47	10.2.171.184/30	10.2.171.185 – 10.2.171.186	10.2.171.187
48	10.2.171.188/30	10.2.171.189 – 10.2.171.190	10.2.171.191
49	10.2.171.192/30	10.2.171.193 – 10.2.171.194	10.2.171.195
50	10.2.171.196/30	10.2.171.197 – 10.2.171.198	10.2.171.199
51	10.2.171.200/30	10.2.171.201 – 10.2.171.202	10.2.171.203
52	10.2.171.204/30	10.2.171.205 – 10.2.171.206	10.2.171.207
53	10.2.171.208/30	10.2.171.209 – 10.2.171.210	10.2.171.211
54	10.2.171.212/30	10.2.171.213 – 10.2.171.214	10.2.171.215
55	10.2.171.216/30	10.2.171.217 – 10.2.171.218	10.2.171.219
56	10.2.171.220/30	10.2.171.221 – 10.2.171.222	10.2.171.223
57	10.2.171.224/30	10.2.171.225 – 10.2.171.226	10.2.171.227
58	10.2.171.228/30	10.2.171.229 – 10.2.171.230	10.2.171.231
59	10.2.171.232/30	10.2.171.233 – 10.2.171.234	10.2.171.235
60	10.2.171.236/30	10.2.171.237 – 10.2.171.238	10.2.171.239
61	10.2.171.240/30	10.2.171.241 – 10.2.171.242	10.2.171.243
62	10.2.171.244/30	10.2.171.245 – 10.2.171.246	10.2.171.247
63	10.2.171.248/30	10.2.171.249 – 10.2.171.250	10.2.171.251
64	10.2.171.252/30	10.2.171.253 – 10.2.171.254	10.2.171.255

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 →