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)10.99.45.0/24

network10.99.45.0/24

broadcast10.99.45.255

first host10.99.45.1

last host10.99.45.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.99.45.0/24

address00001010.01100011.00101101.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.01100011.00101101.00000000

broadcast00001010.01100011.00101101.11111111

green = network part, grey = host part

hex0x0a632d00

decimal174271744

reverse dns0.45.99.10.in-addr.arpa

ipv4-mapped::ffff:a63:2d00

/24 split into /30 · 64 subnets

close ×

#	network	host range	broadcast
1	10.99.45.0/30	10.99.45.1 – 10.99.45.2	10.99.45.3
2	10.99.45.4/30	10.99.45.5 – 10.99.45.6	10.99.45.7
3	10.99.45.8/30	10.99.45.9 – 10.99.45.10	10.99.45.11
4	10.99.45.12/30	10.99.45.13 – 10.99.45.14	10.99.45.15
5	10.99.45.16/30	10.99.45.17 – 10.99.45.18	10.99.45.19
6	10.99.45.20/30	10.99.45.21 – 10.99.45.22	10.99.45.23
7	10.99.45.24/30	10.99.45.25 – 10.99.45.26	10.99.45.27
8	10.99.45.28/30	10.99.45.29 – 10.99.45.30	10.99.45.31
9	10.99.45.32/30	10.99.45.33 – 10.99.45.34	10.99.45.35
10	10.99.45.36/30	10.99.45.37 – 10.99.45.38	10.99.45.39
11	10.99.45.40/30	10.99.45.41 – 10.99.45.42	10.99.45.43
12	10.99.45.44/30	10.99.45.45 – 10.99.45.46	10.99.45.47
13	10.99.45.48/30	10.99.45.49 – 10.99.45.50	10.99.45.51
14	10.99.45.52/30	10.99.45.53 – 10.99.45.54	10.99.45.55
15	10.99.45.56/30	10.99.45.57 – 10.99.45.58	10.99.45.59
16	10.99.45.60/30	10.99.45.61 – 10.99.45.62	10.99.45.63
17	10.99.45.64/30	10.99.45.65 – 10.99.45.66	10.99.45.67
18	10.99.45.68/30	10.99.45.69 – 10.99.45.70	10.99.45.71
19	10.99.45.72/30	10.99.45.73 – 10.99.45.74	10.99.45.75
20	10.99.45.76/30	10.99.45.77 – 10.99.45.78	10.99.45.79
21	10.99.45.80/30	10.99.45.81 – 10.99.45.82	10.99.45.83
22	10.99.45.84/30	10.99.45.85 – 10.99.45.86	10.99.45.87
23	10.99.45.88/30	10.99.45.89 – 10.99.45.90	10.99.45.91
24	10.99.45.92/30	10.99.45.93 – 10.99.45.94	10.99.45.95
25	10.99.45.96/30	10.99.45.97 – 10.99.45.98	10.99.45.99
26	10.99.45.100/30	10.99.45.101 – 10.99.45.102	10.99.45.103
27	10.99.45.104/30	10.99.45.105 – 10.99.45.106	10.99.45.107
28	10.99.45.108/30	10.99.45.109 – 10.99.45.110	10.99.45.111
29	10.99.45.112/30	10.99.45.113 – 10.99.45.114	10.99.45.115
30	10.99.45.116/30	10.99.45.117 – 10.99.45.118	10.99.45.119
31	10.99.45.120/30	10.99.45.121 – 10.99.45.122	10.99.45.123
32	10.99.45.124/30	10.99.45.125 – 10.99.45.126	10.99.45.127
33	10.99.45.128/30	10.99.45.129 – 10.99.45.130	10.99.45.131
34	10.99.45.132/30	10.99.45.133 – 10.99.45.134	10.99.45.135
35	10.99.45.136/30	10.99.45.137 – 10.99.45.138	10.99.45.139
36	10.99.45.140/30	10.99.45.141 – 10.99.45.142	10.99.45.143
37	10.99.45.144/30	10.99.45.145 – 10.99.45.146	10.99.45.147
38	10.99.45.148/30	10.99.45.149 – 10.99.45.150	10.99.45.151
39	10.99.45.152/30	10.99.45.153 – 10.99.45.154	10.99.45.155
40	10.99.45.156/30	10.99.45.157 – 10.99.45.158	10.99.45.159
41	10.99.45.160/30	10.99.45.161 – 10.99.45.162	10.99.45.163
42	10.99.45.164/30	10.99.45.165 – 10.99.45.166	10.99.45.167
43	10.99.45.168/30	10.99.45.169 – 10.99.45.170	10.99.45.171
44	10.99.45.172/30	10.99.45.173 – 10.99.45.174	10.99.45.175
45	10.99.45.176/30	10.99.45.177 – 10.99.45.178	10.99.45.179
46	10.99.45.180/30	10.99.45.181 – 10.99.45.182	10.99.45.183
47	10.99.45.184/30	10.99.45.185 – 10.99.45.186	10.99.45.187
48	10.99.45.188/30	10.99.45.189 – 10.99.45.190	10.99.45.191
49	10.99.45.192/30	10.99.45.193 – 10.99.45.194	10.99.45.195
50	10.99.45.196/30	10.99.45.197 – 10.99.45.198	10.99.45.199
51	10.99.45.200/30	10.99.45.201 – 10.99.45.202	10.99.45.203
52	10.99.45.204/30	10.99.45.205 – 10.99.45.206	10.99.45.207
53	10.99.45.208/30	10.99.45.209 – 10.99.45.210	10.99.45.211
54	10.99.45.212/30	10.99.45.213 – 10.99.45.214	10.99.45.215
55	10.99.45.216/30	10.99.45.217 – 10.99.45.218	10.99.45.219
56	10.99.45.220/30	10.99.45.221 – 10.99.45.222	10.99.45.223
57	10.99.45.224/30	10.99.45.225 – 10.99.45.226	10.99.45.227
58	10.99.45.228/30	10.99.45.229 – 10.99.45.230	10.99.45.231
59	10.99.45.232/30	10.99.45.233 – 10.99.45.234	10.99.45.235
60	10.99.45.236/30	10.99.45.237 – 10.99.45.238	10.99.45.239
61	10.99.45.240/30	10.99.45.241 – 10.99.45.242	10.99.45.243
62	10.99.45.244/30	10.99.45.245 – 10.99.45.246	10.99.45.247
63	10.99.45.248/30	10.99.45.249 – 10.99.45.250	10.99.45.251
64	10.99.45.252/30	10.99.45.253 – 10.99.45.254	10.99.45.255

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 →