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)172.16.4.0/23

network172.16.4.0/23

broadcast172.16.5.255

first host172.16.4.1

last host172.16.5.254

subnet mask255.255.254.0

wildcard0.0.1.255

addresses512

usable hosts510

classB

ipcalc 172.16.4.0/23

address10101100.00010000.00000100.00000000

subnet mask11111111.11111111.11111110.00000000

network10101100.00010000.00000100.00000000

broadcast10101100.00010000.00000101.11111111

green = network part, grey = host part

hex0xac100400

decimal2886730752

reverse dns0.4.16.172.in-addr.arpa

ipv4-mapped::ffff:ac10:400

/23 split into /29 · 64 subnets

close ×

#	network	host range	broadcast
1	172.16.4.0/29	172.16.4.1 – 172.16.4.6	172.16.4.7
2	172.16.4.8/29	172.16.4.9 – 172.16.4.14	172.16.4.15
3	172.16.4.16/29	172.16.4.17 – 172.16.4.22	172.16.4.23
4	172.16.4.24/29	172.16.4.25 – 172.16.4.30	172.16.4.31
5	172.16.4.32/29	172.16.4.33 – 172.16.4.38	172.16.4.39
6	172.16.4.40/29	172.16.4.41 – 172.16.4.46	172.16.4.47
7	172.16.4.48/29	172.16.4.49 – 172.16.4.54	172.16.4.55
8	172.16.4.56/29	172.16.4.57 – 172.16.4.62	172.16.4.63
9	172.16.4.64/29	172.16.4.65 – 172.16.4.70	172.16.4.71
10	172.16.4.72/29	172.16.4.73 – 172.16.4.78	172.16.4.79
11	172.16.4.80/29	172.16.4.81 – 172.16.4.86	172.16.4.87
12	172.16.4.88/29	172.16.4.89 – 172.16.4.94	172.16.4.95
13	172.16.4.96/29	172.16.4.97 – 172.16.4.102	172.16.4.103
14	172.16.4.104/29	172.16.4.105 – 172.16.4.110	172.16.4.111
15	172.16.4.112/29	172.16.4.113 – 172.16.4.118	172.16.4.119
16	172.16.4.120/29	172.16.4.121 – 172.16.4.126	172.16.4.127
17	172.16.4.128/29	172.16.4.129 – 172.16.4.134	172.16.4.135
18	172.16.4.136/29	172.16.4.137 – 172.16.4.142	172.16.4.143
19	172.16.4.144/29	172.16.4.145 – 172.16.4.150	172.16.4.151
20	172.16.4.152/29	172.16.4.153 – 172.16.4.158	172.16.4.159
21	172.16.4.160/29	172.16.4.161 – 172.16.4.166	172.16.4.167
22	172.16.4.168/29	172.16.4.169 – 172.16.4.174	172.16.4.175
23	172.16.4.176/29	172.16.4.177 – 172.16.4.182	172.16.4.183
24	172.16.4.184/29	172.16.4.185 – 172.16.4.190	172.16.4.191
25	172.16.4.192/29	172.16.4.193 – 172.16.4.198	172.16.4.199
26	172.16.4.200/29	172.16.4.201 – 172.16.4.206	172.16.4.207
27	172.16.4.208/29	172.16.4.209 – 172.16.4.214	172.16.4.215
28	172.16.4.216/29	172.16.4.217 – 172.16.4.222	172.16.4.223
29	172.16.4.224/29	172.16.4.225 – 172.16.4.230	172.16.4.231
30	172.16.4.232/29	172.16.4.233 – 172.16.4.238	172.16.4.239
31	172.16.4.240/29	172.16.4.241 – 172.16.4.246	172.16.4.247
32	172.16.4.248/29	172.16.4.249 – 172.16.4.254	172.16.4.255
33	172.16.5.0/29	172.16.5.1 – 172.16.5.6	172.16.5.7
34	172.16.5.8/29	172.16.5.9 – 172.16.5.14	172.16.5.15
35	172.16.5.16/29	172.16.5.17 – 172.16.5.22	172.16.5.23
36	172.16.5.24/29	172.16.5.25 – 172.16.5.30	172.16.5.31
37	172.16.5.32/29	172.16.5.33 – 172.16.5.38	172.16.5.39
38	172.16.5.40/29	172.16.5.41 – 172.16.5.46	172.16.5.47
39	172.16.5.48/29	172.16.5.49 – 172.16.5.54	172.16.5.55
40	172.16.5.56/29	172.16.5.57 – 172.16.5.62	172.16.5.63
41	172.16.5.64/29	172.16.5.65 – 172.16.5.70	172.16.5.71
42	172.16.5.72/29	172.16.5.73 – 172.16.5.78	172.16.5.79
43	172.16.5.80/29	172.16.5.81 – 172.16.5.86	172.16.5.87
44	172.16.5.88/29	172.16.5.89 – 172.16.5.94	172.16.5.95
45	172.16.5.96/29	172.16.5.97 – 172.16.5.102	172.16.5.103
46	172.16.5.104/29	172.16.5.105 – 172.16.5.110	172.16.5.111
47	172.16.5.112/29	172.16.5.113 – 172.16.5.118	172.16.5.119
48	172.16.5.120/29	172.16.5.121 – 172.16.5.126	172.16.5.127
49	172.16.5.128/29	172.16.5.129 – 172.16.5.134	172.16.5.135
50	172.16.5.136/29	172.16.5.137 – 172.16.5.142	172.16.5.143
51	172.16.5.144/29	172.16.5.145 – 172.16.5.150	172.16.5.151
52	172.16.5.152/29	172.16.5.153 – 172.16.5.158	172.16.5.159
53	172.16.5.160/29	172.16.5.161 – 172.16.5.166	172.16.5.167
54	172.16.5.168/29	172.16.5.169 – 172.16.5.174	172.16.5.175
55	172.16.5.176/29	172.16.5.177 – 172.16.5.182	172.16.5.183
56	172.16.5.184/29	172.16.5.185 – 172.16.5.190	172.16.5.191
57	172.16.5.192/29	172.16.5.193 – 172.16.5.198	172.16.5.199
58	172.16.5.200/29	172.16.5.201 – 172.16.5.206	172.16.5.207
59	172.16.5.208/29	172.16.5.209 – 172.16.5.214	172.16.5.215
60	172.16.5.216/29	172.16.5.217 – 172.16.5.222	172.16.5.223
61	172.16.5.224/29	172.16.5.225 – 172.16.5.230	172.16.5.231
62	172.16.5.232/29	172.16.5.233 – 172.16.5.238	172.16.5.239
63	172.16.5.240/29	172.16.5.241 – 172.16.5.246	172.16.5.247
64	172.16.5.248/29	172.16.5.249 – 172.16.5.254	172.16.5.255

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 →