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)10.2.248.0/23

network10.2.248.0/23

broadcast10.2.249.255

first host10.2.248.1

last host10.2.249.254

subnet mask255.255.254.0

wildcard0.0.1.255

addresses512

usable hosts510

classA

ipcalc 10.2.248.0/23

address00001010.00000010.11111000.00000000

subnet mask11111111.11111111.11111110.00000000

network00001010.00000010.11111000.00000000

broadcast00001010.00000010.11111001.11111111

green = network part, grey = host part

hex0x0a02f800

decimal167966720

reverse dns0.248.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:f800

/23 split into /29 · 64 subnets

close ×

#	network	host range	broadcast
1	10.2.248.0/29	10.2.248.1 – 10.2.248.6	10.2.248.7
2	10.2.248.8/29	10.2.248.9 – 10.2.248.14	10.2.248.15
3	10.2.248.16/29	10.2.248.17 – 10.2.248.22	10.2.248.23
4	10.2.248.24/29	10.2.248.25 – 10.2.248.30	10.2.248.31
5	10.2.248.32/29	10.2.248.33 – 10.2.248.38	10.2.248.39
6	10.2.248.40/29	10.2.248.41 – 10.2.248.46	10.2.248.47
7	10.2.248.48/29	10.2.248.49 – 10.2.248.54	10.2.248.55
8	10.2.248.56/29	10.2.248.57 – 10.2.248.62	10.2.248.63
9	10.2.248.64/29	10.2.248.65 – 10.2.248.70	10.2.248.71
10	10.2.248.72/29	10.2.248.73 – 10.2.248.78	10.2.248.79
11	10.2.248.80/29	10.2.248.81 – 10.2.248.86	10.2.248.87
12	10.2.248.88/29	10.2.248.89 – 10.2.248.94	10.2.248.95
13	10.2.248.96/29	10.2.248.97 – 10.2.248.102	10.2.248.103
14	10.2.248.104/29	10.2.248.105 – 10.2.248.110	10.2.248.111
15	10.2.248.112/29	10.2.248.113 – 10.2.248.118	10.2.248.119
16	10.2.248.120/29	10.2.248.121 – 10.2.248.126	10.2.248.127
17	10.2.248.128/29	10.2.248.129 – 10.2.248.134	10.2.248.135
18	10.2.248.136/29	10.2.248.137 – 10.2.248.142	10.2.248.143
19	10.2.248.144/29	10.2.248.145 – 10.2.248.150	10.2.248.151
20	10.2.248.152/29	10.2.248.153 – 10.2.248.158	10.2.248.159
21	10.2.248.160/29	10.2.248.161 – 10.2.248.166	10.2.248.167
22	10.2.248.168/29	10.2.248.169 – 10.2.248.174	10.2.248.175
23	10.2.248.176/29	10.2.248.177 – 10.2.248.182	10.2.248.183
24	10.2.248.184/29	10.2.248.185 – 10.2.248.190	10.2.248.191
25	10.2.248.192/29	10.2.248.193 – 10.2.248.198	10.2.248.199
26	10.2.248.200/29	10.2.248.201 – 10.2.248.206	10.2.248.207
27	10.2.248.208/29	10.2.248.209 – 10.2.248.214	10.2.248.215
28	10.2.248.216/29	10.2.248.217 – 10.2.248.222	10.2.248.223
29	10.2.248.224/29	10.2.248.225 – 10.2.248.230	10.2.248.231
30	10.2.248.232/29	10.2.248.233 – 10.2.248.238	10.2.248.239
31	10.2.248.240/29	10.2.248.241 – 10.2.248.246	10.2.248.247
32	10.2.248.248/29	10.2.248.249 – 10.2.248.254	10.2.248.255
33	10.2.249.0/29	10.2.249.1 – 10.2.249.6	10.2.249.7
34	10.2.249.8/29	10.2.249.9 – 10.2.249.14	10.2.249.15
35	10.2.249.16/29	10.2.249.17 – 10.2.249.22	10.2.249.23
36	10.2.249.24/29	10.2.249.25 – 10.2.249.30	10.2.249.31
37	10.2.249.32/29	10.2.249.33 – 10.2.249.38	10.2.249.39
38	10.2.249.40/29	10.2.249.41 – 10.2.249.46	10.2.249.47
39	10.2.249.48/29	10.2.249.49 – 10.2.249.54	10.2.249.55
40	10.2.249.56/29	10.2.249.57 – 10.2.249.62	10.2.249.63
41	10.2.249.64/29	10.2.249.65 – 10.2.249.70	10.2.249.71
42	10.2.249.72/29	10.2.249.73 – 10.2.249.78	10.2.249.79
43	10.2.249.80/29	10.2.249.81 – 10.2.249.86	10.2.249.87
44	10.2.249.88/29	10.2.249.89 – 10.2.249.94	10.2.249.95
45	10.2.249.96/29	10.2.249.97 – 10.2.249.102	10.2.249.103
46	10.2.249.104/29	10.2.249.105 – 10.2.249.110	10.2.249.111
47	10.2.249.112/29	10.2.249.113 – 10.2.249.118	10.2.249.119
48	10.2.249.120/29	10.2.249.121 – 10.2.249.126	10.2.249.127
49	10.2.249.128/29	10.2.249.129 – 10.2.249.134	10.2.249.135
50	10.2.249.136/29	10.2.249.137 – 10.2.249.142	10.2.249.143
51	10.2.249.144/29	10.2.249.145 – 10.2.249.150	10.2.249.151
52	10.2.249.152/29	10.2.249.153 – 10.2.249.158	10.2.249.159
53	10.2.249.160/29	10.2.249.161 – 10.2.249.166	10.2.249.167
54	10.2.249.168/29	10.2.249.169 – 10.2.249.174	10.2.249.175
55	10.2.249.176/29	10.2.249.177 – 10.2.249.182	10.2.249.183
56	10.2.249.184/29	10.2.249.185 – 10.2.249.190	10.2.249.191
57	10.2.249.192/29	10.2.249.193 – 10.2.249.198	10.2.249.199
58	10.2.249.200/29	10.2.249.201 – 10.2.249.206	10.2.249.207
59	10.2.249.208/29	10.2.249.209 – 10.2.249.214	10.2.249.215
60	10.2.249.216/29	10.2.249.217 – 10.2.249.222	10.2.249.223
61	10.2.249.224/29	10.2.249.225 – 10.2.249.230	10.2.249.231
62	10.2.249.232/29	10.2.249.233 – 10.2.249.238	10.2.249.239
63	10.2.249.240/29	10.2.249.241 – 10.2.249.246	10.2.249.247
64	10.2.249.248/29	10.2.249.249 – 10.2.249.254	10.2.249.255

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 →