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)10.3.156.0/23

network10.3.156.0/23

broadcast10.3.157.255

first host10.3.156.1

last host10.3.157.254

subnet mask255.255.254.0

wildcard0.0.1.255

addresses512

usable hosts510

classA

ipcalc 10.3.156.0/23

address00001010.00000011.10011100.00000000

subnet mask11111111.11111111.11111110.00000000

network00001010.00000011.10011100.00000000

broadcast00001010.00000011.10011101.11111111

green = network part, grey = host part

hex0x0a039c00

decimal168008704

reverse dns0.156.3.10.in-addr.arpa

ipv4-mapped::ffff:a03:9c00

/23 split into /29 · 64 subnets

close ×

#	network	host range	broadcast
1	10.3.156.0/29	10.3.156.1 – 10.3.156.6	10.3.156.7
2	10.3.156.8/29	10.3.156.9 – 10.3.156.14	10.3.156.15
3	10.3.156.16/29	10.3.156.17 – 10.3.156.22	10.3.156.23
4	10.3.156.24/29	10.3.156.25 – 10.3.156.30	10.3.156.31
5	10.3.156.32/29	10.3.156.33 – 10.3.156.38	10.3.156.39
6	10.3.156.40/29	10.3.156.41 – 10.3.156.46	10.3.156.47
7	10.3.156.48/29	10.3.156.49 – 10.3.156.54	10.3.156.55
8	10.3.156.56/29	10.3.156.57 – 10.3.156.62	10.3.156.63
9	10.3.156.64/29	10.3.156.65 – 10.3.156.70	10.3.156.71
10	10.3.156.72/29	10.3.156.73 – 10.3.156.78	10.3.156.79
11	10.3.156.80/29	10.3.156.81 – 10.3.156.86	10.3.156.87
12	10.3.156.88/29	10.3.156.89 – 10.3.156.94	10.3.156.95
13	10.3.156.96/29	10.3.156.97 – 10.3.156.102	10.3.156.103
14	10.3.156.104/29	10.3.156.105 – 10.3.156.110	10.3.156.111
15	10.3.156.112/29	10.3.156.113 – 10.3.156.118	10.3.156.119
16	10.3.156.120/29	10.3.156.121 – 10.3.156.126	10.3.156.127
17	10.3.156.128/29	10.3.156.129 – 10.3.156.134	10.3.156.135
18	10.3.156.136/29	10.3.156.137 – 10.3.156.142	10.3.156.143
19	10.3.156.144/29	10.3.156.145 – 10.3.156.150	10.3.156.151
20	10.3.156.152/29	10.3.156.153 – 10.3.156.158	10.3.156.159
21	10.3.156.160/29	10.3.156.161 – 10.3.156.166	10.3.156.167
22	10.3.156.168/29	10.3.156.169 – 10.3.156.174	10.3.156.175
23	10.3.156.176/29	10.3.156.177 – 10.3.156.182	10.3.156.183
24	10.3.156.184/29	10.3.156.185 – 10.3.156.190	10.3.156.191
25	10.3.156.192/29	10.3.156.193 – 10.3.156.198	10.3.156.199
26	10.3.156.200/29	10.3.156.201 – 10.3.156.206	10.3.156.207
27	10.3.156.208/29	10.3.156.209 – 10.3.156.214	10.3.156.215
28	10.3.156.216/29	10.3.156.217 – 10.3.156.222	10.3.156.223
29	10.3.156.224/29	10.3.156.225 – 10.3.156.230	10.3.156.231
30	10.3.156.232/29	10.3.156.233 – 10.3.156.238	10.3.156.239
31	10.3.156.240/29	10.3.156.241 – 10.3.156.246	10.3.156.247
32	10.3.156.248/29	10.3.156.249 – 10.3.156.254	10.3.156.255
33	10.3.157.0/29	10.3.157.1 – 10.3.157.6	10.3.157.7
34	10.3.157.8/29	10.3.157.9 – 10.3.157.14	10.3.157.15
35	10.3.157.16/29	10.3.157.17 – 10.3.157.22	10.3.157.23
36	10.3.157.24/29	10.3.157.25 – 10.3.157.30	10.3.157.31
37	10.3.157.32/29	10.3.157.33 – 10.3.157.38	10.3.157.39
38	10.3.157.40/29	10.3.157.41 – 10.3.157.46	10.3.157.47
39	10.3.157.48/29	10.3.157.49 – 10.3.157.54	10.3.157.55
40	10.3.157.56/29	10.3.157.57 – 10.3.157.62	10.3.157.63
41	10.3.157.64/29	10.3.157.65 – 10.3.157.70	10.3.157.71
42	10.3.157.72/29	10.3.157.73 – 10.3.157.78	10.3.157.79
43	10.3.157.80/29	10.3.157.81 – 10.3.157.86	10.3.157.87
44	10.3.157.88/29	10.3.157.89 – 10.3.157.94	10.3.157.95
45	10.3.157.96/29	10.3.157.97 – 10.3.157.102	10.3.157.103
46	10.3.157.104/29	10.3.157.105 – 10.3.157.110	10.3.157.111
47	10.3.157.112/29	10.3.157.113 – 10.3.157.118	10.3.157.119
48	10.3.157.120/29	10.3.157.121 – 10.3.157.126	10.3.157.127
49	10.3.157.128/29	10.3.157.129 – 10.3.157.134	10.3.157.135
50	10.3.157.136/29	10.3.157.137 – 10.3.157.142	10.3.157.143
51	10.3.157.144/29	10.3.157.145 – 10.3.157.150	10.3.157.151
52	10.3.157.152/29	10.3.157.153 – 10.3.157.158	10.3.157.159
53	10.3.157.160/29	10.3.157.161 – 10.3.157.166	10.3.157.167
54	10.3.157.168/29	10.3.157.169 – 10.3.157.174	10.3.157.175
55	10.3.157.176/29	10.3.157.177 – 10.3.157.182	10.3.157.183
56	10.3.157.184/29	10.3.157.185 – 10.3.157.190	10.3.157.191
57	10.3.157.192/29	10.3.157.193 – 10.3.157.198	10.3.157.199
58	10.3.157.200/29	10.3.157.201 – 10.3.157.206	10.3.157.207
59	10.3.157.208/29	10.3.157.209 – 10.3.157.214	10.3.157.215
60	10.3.157.216/29	10.3.157.217 – 10.3.157.222	10.3.157.223
61	10.3.157.224/29	10.3.157.225 – 10.3.157.230	10.3.157.231
62	10.3.157.232/29	10.3.157.233 – 10.3.157.238	10.3.157.239
63	10.3.157.240/29	10.3.157.241 – 10.3.157.246	10.3.157.247
64	10.3.157.248/29	10.3.157.249 – 10.3.157.254	10.3.157.255

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 →