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)172.16.10.0/23

network172.16.10.0/23

broadcast172.16.11.255

first host172.16.10.1

last host172.16.11.254

subnet mask255.255.254.0

wildcard0.0.1.255

addresses512

usable hosts510

classB

ipcalc 172.16.10.0/23

address10101100.00010000.00001010.00000000

subnet mask11111111.11111111.11111110.00000000

network10101100.00010000.00001010.00000000

broadcast10101100.00010000.00001011.11111111

green = network part, grey = host part

hex0xac100a00

decimal2886732288

reverse dns0.10.16.172.in-addr.arpa

ipv4-mapped::ffff:ac10:a00

/23 split into /29 · 64 subnets

close ×

#	network	host range	broadcast
1	172.16.10.0/29	172.16.10.1 – 172.16.10.6	172.16.10.7
2	172.16.10.8/29	172.16.10.9 – 172.16.10.14	172.16.10.15
3	172.16.10.16/29	172.16.10.17 – 172.16.10.22	172.16.10.23
4	172.16.10.24/29	172.16.10.25 – 172.16.10.30	172.16.10.31
5	172.16.10.32/29	172.16.10.33 – 172.16.10.38	172.16.10.39
6	172.16.10.40/29	172.16.10.41 – 172.16.10.46	172.16.10.47
7	172.16.10.48/29	172.16.10.49 – 172.16.10.54	172.16.10.55
8	172.16.10.56/29	172.16.10.57 – 172.16.10.62	172.16.10.63
9	172.16.10.64/29	172.16.10.65 – 172.16.10.70	172.16.10.71
10	172.16.10.72/29	172.16.10.73 – 172.16.10.78	172.16.10.79
11	172.16.10.80/29	172.16.10.81 – 172.16.10.86	172.16.10.87
12	172.16.10.88/29	172.16.10.89 – 172.16.10.94	172.16.10.95
13	172.16.10.96/29	172.16.10.97 – 172.16.10.102	172.16.10.103
14	172.16.10.104/29	172.16.10.105 – 172.16.10.110	172.16.10.111
15	172.16.10.112/29	172.16.10.113 – 172.16.10.118	172.16.10.119
16	172.16.10.120/29	172.16.10.121 – 172.16.10.126	172.16.10.127
17	172.16.10.128/29	172.16.10.129 – 172.16.10.134	172.16.10.135
18	172.16.10.136/29	172.16.10.137 – 172.16.10.142	172.16.10.143
19	172.16.10.144/29	172.16.10.145 – 172.16.10.150	172.16.10.151
20	172.16.10.152/29	172.16.10.153 – 172.16.10.158	172.16.10.159
21	172.16.10.160/29	172.16.10.161 – 172.16.10.166	172.16.10.167
22	172.16.10.168/29	172.16.10.169 – 172.16.10.174	172.16.10.175
23	172.16.10.176/29	172.16.10.177 – 172.16.10.182	172.16.10.183
24	172.16.10.184/29	172.16.10.185 – 172.16.10.190	172.16.10.191
25	172.16.10.192/29	172.16.10.193 – 172.16.10.198	172.16.10.199
26	172.16.10.200/29	172.16.10.201 – 172.16.10.206	172.16.10.207
27	172.16.10.208/29	172.16.10.209 – 172.16.10.214	172.16.10.215
28	172.16.10.216/29	172.16.10.217 – 172.16.10.222	172.16.10.223
29	172.16.10.224/29	172.16.10.225 – 172.16.10.230	172.16.10.231
30	172.16.10.232/29	172.16.10.233 – 172.16.10.238	172.16.10.239
31	172.16.10.240/29	172.16.10.241 – 172.16.10.246	172.16.10.247
32	172.16.10.248/29	172.16.10.249 – 172.16.10.254	172.16.10.255
33	172.16.11.0/29	172.16.11.1 – 172.16.11.6	172.16.11.7
34	172.16.11.8/29	172.16.11.9 – 172.16.11.14	172.16.11.15
35	172.16.11.16/29	172.16.11.17 – 172.16.11.22	172.16.11.23
36	172.16.11.24/29	172.16.11.25 – 172.16.11.30	172.16.11.31
37	172.16.11.32/29	172.16.11.33 – 172.16.11.38	172.16.11.39
38	172.16.11.40/29	172.16.11.41 – 172.16.11.46	172.16.11.47
39	172.16.11.48/29	172.16.11.49 – 172.16.11.54	172.16.11.55
40	172.16.11.56/29	172.16.11.57 – 172.16.11.62	172.16.11.63
41	172.16.11.64/29	172.16.11.65 – 172.16.11.70	172.16.11.71
42	172.16.11.72/29	172.16.11.73 – 172.16.11.78	172.16.11.79
43	172.16.11.80/29	172.16.11.81 – 172.16.11.86	172.16.11.87
44	172.16.11.88/29	172.16.11.89 – 172.16.11.94	172.16.11.95
45	172.16.11.96/29	172.16.11.97 – 172.16.11.102	172.16.11.103
46	172.16.11.104/29	172.16.11.105 – 172.16.11.110	172.16.11.111
47	172.16.11.112/29	172.16.11.113 – 172.16.11.118	172.16.11.119
48	172.16.11.120/29	172.16.11.121 – 172.16.11.126	172.16.11.127
49	172.16.11.128/29	172.16.11.129 – 172.16.11.134	172.16.11.135
50	172.16.11.136/29	172.16.11.137 – 172.16.11.142	172.16.11.143
51	172.16.11.144/29	172.16.11.145 – 172.16.11.150	172.16.11.151
52	172.16.11.152/29	172.16.11.153 – 172.16.11.158	172.16.11.159
53	172.16.11.160/29	172.16.11.161 – 172.16.11.166	172.16.11.167
54	172.16.11.168/29	172.16.11.169 – 172.16.11.174	172.16.11.175
55	172.16.11.176/29	172.16.11.177 – 172.16.11.182	172.16.11.183
56	172.16.11.184/29	172.16.11.185 – 172.16.11.190	172.16.11.191
57	172.16.11.192/29	172.16.11.193 – 172.16.11.198	172.16.11.199
58	172.16.11.200/29	172.16.11.201 – 172.16.11.206	172.16.11.207
59	172.16.11.208/29	172.16.11.209 – 172.16.11.214	172.16.11.215
60	172.16.11.216/29	172.16.11.217 – 172.16.11.222	172.16.11.223
61	172.16.11.224/29	172.16.11.225 – 172.16.11.230	172.16.11.231
62	172.16.11.232/29	172.16.11.233 – 172.16.11.238	172.16.11.239
63	172.16.11.240/29	172.16.11.241 – 172.16.11.246	172.16.11.247
64	172.16.11.248/29	172.16.11.249 – 172.16.11.254	172.16.11.255

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 →