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)10.4.28.0/23

network10.4.28.0/23

broadcast10.4.29.255

first host10.4.28.1

last host10.4.29.254

subnet mask255.255.254.0

wildcard0.0.1.255

addresses512

usable hosts510

classA

ipcalc 10.4.28.0/23

address00001010.00000100.00011100.00000000

subnet mask11111111.11111111.11111110.00000000

network00001010.00000100.00011100.00000000

broadcast00001010.00000100.00011101.11111111

green = network part, grey = host part

hex0x0a041c00

decimal168041472

reverse dns0.28.4.10.in-addr.arpa

ipv4-mapped::ffff:a04:1c00

/23 split into /29 · 64 subnets

close ×

#	network	host range	broadcast
1	10.4.28.0/29	10.4.28.1 – 10.4.28.6	10.4.28.7
2	10.4.28.8/29	10.4.28.9 – 10.4.28.14	10.4.28.15
3	10.4.28.16/29	10.4.28.17 – 10.4.28.22	10.4.28.23
4	10.4.28.24/29	10.4.28.25 – 10.4.28.30	10.4.28.31
5	10.4.28.32/29	10.4.28.33 – 10.4.28.38	10.4.28.39
6	10.4.28.40/29	10.4.28.41 – 10.4.28.46	10.4.28.47
7	10.4.28.48/29	10.4.28.49 – 10.4.28.54	10.4.28.55
8	10.4.28.56/29	10.4.28.57 – 10.4.28.62	10.4.28.63
9	10.4.28.64/29	10.4.28.65 – 10.4.28.70	10.4.28.71
10	10.4.28.72/29	10.4.28.73 – 10.4.28.78	10.4.28.79
11	10.4.28.80/29	10.4.28.81 – 10.4.28.86	10.4.28.87
12	10.4.28.88/29	10.4.28.89 – 10.4.28.94	10.4.28.95
13	10.4.28.96/29	10.4.28.97 – 10.4.28.102	10.4.28.103
14	10.4.28.104/29	10.4.28.105 – 10.4.28.110	10.4.28.111
15	10.4.28.112/29	10.4.28.113 – 10.4.28.118	10.4.28.119
16	10.4.28.120/29	10.4.28.121 – 10.4.28.126	10.4.28.127
17	10.4.28.128/29	10.4.28.129 – 10.4.28.134	10.4.28.135
18	10.4.28.136/29	10.4.28.137 – 10.4.28.142	10.4.28.143
19	10.4.28.144/29	10.4.28.145 – 10.4.28.150	10.4.28.151
20	10.4.28.152/29	10.4.28.153 – 10.4.28.158	10.4.28.159
21	10.4.28.160/29	10.4.28.161 – 10.4.28.166	10.4.28.167
22	10.4.28.168/29	10.4.28.169 – 10.4.28.174	10.4.28.175
23	10.4.28.176/29	10.4.28.177 – 10.4.28.182	10.4.28.183
24	10.4.28.184/29	10.4.28.185 – 10.4.28.190	10.4.28.191
25	10.4.28.192/29	10.4.28.193 – 10.4.28.198	10.4.28.199
26	10.4.28.200/29	10.4.28.201 – 10.4.28.206	10.4.28.207
27	10.4.28.208/29	10.4.28.209 – 10.4.28.214	10.4.28.215
28	10.4.28.216/29	10.4.28.217 – 10.4.28.222	10.4.28.223
29	10.4.28.224/29	10.4.28.225 – 10.4.28.230	10.4.28.231
30	10.4.28.232/29	10.4.28.233 – 10.4.28.238	10.4.28.239
31	10.4.28.240/29	10.4.28.241 – 10.4.28.246	10.4.28.247
32	10.4.28.248/29	10.4.28.249 – 10.4.28.254	10.4.28.255
33	10.4.29.0/29	10.4.29.1 – 10.4.29.6	10.4.29.7
34	10.4.29.8/29	10.4.29.9 – 10.4.29.14	10.4.29.15
35	10.4.29.16/29	10.4.29.17 – 10.4.29.22	10.4.29.23
36	10.4.29.24/29	10.4.29.25 – 10.4.29.30	10.4.29.31
37	10.4.29.32/29	10.4.29.33 – 10.4.29.38	10.4.29.39
38	10.4.29.40/29	10.4.29.41 – 10.4.29.46	10.4.29.47
39	10.4.29.48/29	10.4.29.49 – 10.4.29.54	10.4.29.55
40	10.4.29.56/29	10.4.29.57 – 10.4.29.62	10.4.29.63
41	10.4.29.64/29	10.4.29.65 – 10.4.29.70	10.4.29.71
42	10.4.29.72/29	10.4.29.73 – 10.4.29.78	10.4.29.79
43	10.4.29.80/29	10.4.29.81 – 10.4.29.86	10.4.29.87
44	10.4.29.88/29	10.4.29.89 – 10.4.29.94	10.4.29.95
45	10.4.29.96/29	10.4.29.97 – 10.4.29.102	10.4.29.103
46	10.4.29.104/29	10.4.29.105 – 10.4.29.110	10.4.29.111
47	10.4.29.112/29	10.4.29.113 – 10.4.29.118	10.4.29.119
48	10.4.29.120/29	10.4.29.121 – 10.4.29.126	10.4.29.127
49	10.4.29.128/29	10.4.29.129 – 10.4.29.134	10.4.29.135
50	10.4.29.136/29	10.4.29.137 – 10.4.29.142	10.4.29.143
51	10.4.29.144/29	10.4.29.145 – 10.4.29.150	10.4.29.151
52	10.4.29.152/29	10.4.29.153 – 10.4.29.158	10.4.29.159
53	10.4.29.160/29	10.4.29.161 – 10.4.29.166	10.4.29.167
54	10.4.29.168/29	10.4.29.169 – 10.4.29.174	10.4.29.175
55	10.4.29.176/29	10.4.29.177 – 10.4.29.182	10.4.29.183
56	10.4.29.184/29	10.4.29.185 – 10.4.29.190	10.4.29.191
57	10.4.29.192/29	10.4.29.193 – 10.4.29.198	10.4.29.199
58	10.4.29.200/29	10.4.29.201 – 10.4.29.206	10.4.29.207
59	10.4.29.208/29	10.4.29.209 – 10.4.29.214	10.4.29.215
60	10.4.29.216/29	10.4.29.217 – 10.4.29.222	10.4.29.223
61	10.4.29.224/29	10.4.29.225 – 10.4.29.230	10.4.29.231
62	10.4.29.232/29	10.4.29.233 – 10.4.29.238	10.4.29.239
63	10.4.29.240/29	10.4.29.241 – 10.4.29.246	10.4.29.247
64	10.4.29.248/29	10.4.29.249 – 10.4.29.254	10.4.29.255

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 /23
/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	1
/24	255.255.255.0	256	254	2 split →
/25	255.255.255.128	128	126	4 split →
/26	255.255.255.192	64	62	8 split →
/27	255.255.255.224	32	30	16 split →
/28	255.255.255.240	16	14	32 split →
/29	255.255.255.248	8	6	64 split →
/30	255.255.255.252	4	2	128 split →
/31	255.255.255.254	2	2	256 split →
/32	255.255.255.255	1	1	512 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 →