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)10.2.178.0/23

network10.2.178.0/23

broadcast10.2.179.255

first host10.2.178.1

last host10.2.179.254

subnet mask255.255.254.0

wildcard0.0.1.255

addresses512

usable hosts510

classA

ipcalc 10.2.178.0/23

address00001010.00000010.10110010.00000000

subnet mask11111111.11111111.11111110.00000000

network00001010.00000010.10110010.00000000

broadcast00001010.00000010.10110011.11111111

green = network part, grey = host part

hex0x0a02b200

decimal167948800

reverse dns0.178.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:b200

/23 split into /29 · 64 subnets

close ×

#	network	host range	broadcast
1	10.2.178.0/29	10.2.178.1 – 10.2.178.6	10.2.178.7
2	10.2.178.8/29	10.2.178.9 – 10.2.178.14	10.2.178.15
3	10.2.178.16/29	10.2.178.17 – 10.2.178.22	10.2.178.23
4	10.2.178.24/29	10.2.178.25 – 10.2.178.30	10.2.178.31
5	10.2.178.32/29	10.2.178.33 – 10.2.178.38	10.2.178.39
6	10.2.178.40/29	10.2.178.41 – 10.2.178.46	10.2.178.47
7	10.2.178.48/29	10.2.178.49 – 10.2.178.54	10.2.178.55
8	10.2.178.56/29	10.2.178.57 – 10.2.178.62	10.2.178.63
9	10.2.178.64/29	10.2.178.65 – 10.2.178.70	10.2.178.71
10	10.2.178.72/29	10.2.178.73 – 10.2.178.78	10.2.178.79
11	10.2.178.80/29	10.2.178.81 – 10.2.178.86	10.2.178.87
12	10.2.178.88/29	10.2.178.89 – 10.2.178.94	10.2.178.95
13	10.2.178.96/29	10.2.178.97 – 10.2.178.102	10.2.178.103
14	10.2.178.104/29	10.2.178.105 – 10.2.178.110	10.2.178.111
15	10.2.178.112/29	10.2.178.113 – 10.2.178.118	10.2.178.119
16	10.2.178.120/29	10.2.178.121 – 10.2.178.126	10.2.178.127
17	10.2.178.128/29	10.2.178.129 – 10.2.178.134	10.2.178.135
18	10.2.178.136/29	10.2.178.137 – 10.2.178.142	10.2.178.143
19	10.2.178.144/29	10.2.178.145 – 10.2.178.150	10.2.178.151
20	10.2.178.152/29	10.2.178.153 – 10.2.178.158	10.2.178.159
21	10.2.178.160/29	10.2.178.161 – 10.2.178.166	10.2.178.167
22	10.2.178.168/29	10.2.178.169 – 10.2.178.174	10.2.178.175
23	10.2.178.176/29	10.2.178.177 – 10.2.178.182	10.2.178.183
24	10.2.178.184/29	10.2.178.185 – 10.2.178.190	10.2.178.191
25	10.2.178.192/29	10.2.178.193 – 10.2.178.198	10.2.178.199
26	10.2.178.200/29	10.2.178.201 – 10.2.178.206	10.2.178.207
27	10.2.178.208/29	10.2.178.209 – 10.2.178.214	10.2.178.215
28	10.2.178.216/29	10.2.178.217 – 10.2.178.222	10.2.178.223
29	10.2.178.224/29	10.2.178.225 – 10.2.178.230	10.2.178.231
30	10.2.178.232/29	10.2.178.233 – 10.2.178.238	10.2.178.239
31	10.2.178.240/29	10.2.178.241 – 10.2.178.246	10.2.178.247
32	10.2.178.248/29	10.2.178.249 – 10.2.178.254	10.2.178.255
33	10.2.179.0/29	10.2.179.1 – 10.2.179.6	10.2.179.7
34	10.2.179.8/29	10.2.179.9 – 10.2.179.14	10.2.179.15
35	10.2.179.16/29	10.2.179.17 – 10.2.179.22	10.2.179.23
36	10.2.179.24/29	10.2.179.25 – 10.2.179.30	10.2.179.31
37	10.2.179.32/29	10.2.179.33 – 10.2.179.38	10.2.179.39
38	10.2.179.40/29	10.2.179.41 – 10.2.179.46	10.2.179.47
39	10.2.179.48/29	10.2.179.49 – 10.2.179.54	10.2.179.55
40	10.2.179.56/29	10.2.179.57 – 10.2.179.62	10.2.179.63
41	10.2.179.64/29	10.2.179.65 – 10.2.179.70	10.2.179.71
42	10.2.179.72/29	10.2.179.73 – 10.2.179.78	10.2.179.79
43	10.2.179.80/29	10.2.179.81 – 10.2.179.86	10.2.179.87
44	10.2.179.88/29	10.2.179.89 – 10.2.179.94	10.2.179.95
45	10.2.179.96/29	10.2.179.97 – 10.2.179.102	10.2.179.103
46	10.2.179.104/29	10.2.179.105 – 10.2.179.110	10.2.179.111
47	10.2.179.112/29	10.2.179.113 – 10.2.179.118	10.2.179.119
48	10.2.179.120/29	10.2.179.121 – 10.2.179.126	10.2.179.127
49	10.2.179.128/29	10.2.179.129 – 10.2.179.134	10.2.179.135
50	10.2.179.136/29	10.2.179.137 – 10.2.179.142	10.2.179.143
51	10.2.179.144/29	10.2.179.145 – 10.2.179.150	10.2.179.151
52	10.2.179.152/29	10.2.179.153 – 10.2.179.158	10.2.179.159
53	10.2.179.160/29	10.2.179.161 – 10.2.179.166	10.2.179.167
54	10.2.179.168/29	10.2.179.169 – 10.2.179.174	10.2.179.175
55	10.2.179.176/29	10.2.179.177 – 10.2.179.182	10.2.179.183
56	10.2.179.184/29	10.2.179.185 – 10.2.179.190	10.2.179.191
57	10.2.179.192/29	10.2.179.193 – 10.2.179.198	10.2.179.199
58	10.2.179.200/29	10.2.179.201 – 10.2.179.206	10.2.179.207
59	10.2.179.208/29	10.2.179.209 – 10.2.179.214	10.2.179.215
60	10.2.179.216/29	10.2.179.217 – 10.2.179.222	10.2.179.223
61	10.2.179.224/29	10.2.179.225 – 10.2.179.230	10.2.179.231
62	10.2.179.232/29	10.2.179.233 – 10.2.179.238	10.2.179.239
63	10.2.179.240/29	10.2.179.241 – 10.2.179.246	10.2.179.247
64	10.2.179.248/29	10.2.179.249 – 10.2.179.254	10.2.179.255

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 →