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)10.2.232.0/21

network10.2.232.0/21

broadcast10.2.239.255

first host10.2.232.1

last host10.2.239.254

subnet mask255.255.248.0

wildcard0.0.7.255

addresses2,048

usable hosts2,046

classA

ipcalc 10.2.232.0/21

address00001010.00000010.11101000.00000000

subnet mask11111111.11111111.11111000.00000000

network00001010.00000010.11101000.00000000

broadcast00001010.00000010.11101111.11111111

green = network part, grey = host part

hex0x0a02e800

decimal167962624

reverse dns0.232.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:e800

/21 split into /28 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.232.0/28	10.2.232.1 – 10.2.232.14	10.2.232.15
2	10.2.232.16/28	10.2.232.17 – 10.2.232.30	10.2.232.31
3	10.2.232.32/28	10.2.232.33 – 10.2.232.46	10.2.232.47
4	10.2.232.48/28	10.2.232.49 – 10.2.232.62	10.2.232.63
5	10.2.232.64/28	10.2.232.65 – 10.2.232.78	10.2.232.79
6	10.2.232.80/28	10.2.232.81 – 10.2.232.94	10.2.232.95
7	10.2.232.96/28	10.2.232.97 – 10.2.232.110	10.2.232.111
8	10.2.232.112/28	10.2.232.113 – 10.2.232.126	10.2.232.127
9	10.2.232.128/28	10.2.232.129 – 10.2.232.142	10.2.232.143
10	10.2.232.144/28	10.2.232.145 – 10.2.232.158	10.2.232.159
11	10.2.232.160/28	10.2.232.161 – 10.2.232.174	10.2.232.175
12	10.2.232.176/28	10.2.232.177 – 10.2.232.190	10.2.232.191
13	10.2.232.192/28	10.2.232.193 – 10.2.232.206	10.2.232.207
14	10.2.232.208/28	10.2.232.209 – 10.2.232.222	10.2.232.223
15	10.2.232.224/28	10.2.232.225 – 10.2.232.238	10.2.232.239
16	10.2.232.240/28	10.2.232.241 – 10.2.232.254	10.2.232.255
17	10.2.233.0/28	10.2.233.1 – 10.2.233.14	10.2.233.15
18	10.2.233.16/28	10.2.233.17 – 10.2.233.30	10.2.233.31
19	10.2.233.32/28	10.2.233.33 – 10.2.233.46	10.2.233.47
20	10.2.233.48/28	10.2.233.49 – 10.2.233.62	10.2.233.63
21	10.2.233.64/28	10.2.233.65 – 10.2.233.78	10.2.233.79
22	10.2.233.80/28	10.2.233.81 – 10.2.233.94	10.2.233.95
23	10.2.233.96/28	10.2.233.97 – 10.2.233.110	10.2.233.111
24	10.2.233.112/28	10.2.233.113 – 10.2.233.126	10.2.233.127
25	10.2.233.128/28	10.2.233.129 – 10.2.233.142	10.2.233.143
26	10.2.233.144/28	10.2.233.145 – 10.2.233.158	10.2.233.159
27	10.2.233.160/28	10.2.233.161 – 10.2.233.174	10.2.233.175
28	10.2.233.176/28	10.2.233.177 – 10.2.233.190	10.2.233.191
29	10.2.233.192/28	10.2.233.193 – 10.2.233.206	10.2.233.207
30	10.2.233.208/28	10.2.233.209 – 10.2.233.222	10.2.233.223
31	10.2.233.224/28	10.2.233.225 – 10.2.233.238	10.2.233.239
32	10.2.233.240/28	10.2.233.241 – 10.2.233.254	10.2.233.255
33	10.2.234.0/28	10.2.234.1 – 10.2.234.14	10.2.234.15
34	10.2.234.16/28	10.2.234.17 – 10.2.234.30	10.2.234.31
35	10.2.234.32/28	10.2.234.33 – 10.2.234.46	10.2.234.47
36	10.2.234.48/28	10.2.234.49 – 10.2.234.62	10.2.234.63
37	10.2.234.64/28	10.2.234.65 – 10.2.234.78	10.2.234.79
38	10.2.234.80/28	10.2.234.81 – 10.2.234.94	10.2.234.95
39	10.2.234.96/28	10.2.234.97 – 10.2.234.110	10.2.234.111
40	10.2.234.112/28	10.2.234.113 – 10.2.234.126	10.2.234.127
41	10.2.234.128/28	10.2.234.129 – 10.2.234.142	10.2.234.143
42	10.2.234.144/28	10.2.234.145 – 10.2.234.158	10.2.234.159
43	10.2.234.160/28	10.2.234.161 – 10.2.234.174	10.2.234.175
44	10.2.234.176/28	10.2.234.177 – 10.2.234.190	10.2.234.191
45	10.2.234.192/28	10.2.234.193 – 10.2.234.206	10.2.234.207
46	10.2.234.208/28	10.2.234.209 – 10.2.234.222	10.2.234.223
47	10.2.234.224/28	10.2.234.225 – 10.2.234.238	10.2.234.239
48	10.2.234.240/28	10.2.234.241 – 10.2.234.254	10.2.234.255
49	10.2.235.0/28	10.2.235.1 – 10.2.235.14	10.2.235.15
50	10.2.235.16/28	10.2.235.17 – 10.2.235.30	10.2.235.31
51	10.2.235.32/28	10.2.235.33 – 10.2.235.46	10.2.235.47
52	10.2.235.48/28	10.2.235.49 – 10.2.235.62	10.2.235.63
53	10.2.235.64/28	10.2.235.65 – 10.2.235.78	10.2.235.79
54	10.2.235.80/28	10.2.235.81 – 10.2.235.94	10.2.235.95
55	10.2.235.96/28	10.2.235.97 – 10.2.235.110	10.2.235.111
56	10.2.235.112/28	10.2.235.113 – 10.2.235.126	10.2.235.127
57	10.2.235.128/28	10.2.235.129 – 10.2.235.142	10.2.235.143
58	10.2.235.144/28	10.2.235.145 – 10.2.235.158	10.2.235.159
59	10.2.235.160/28	10.2.235.161 – 10.2.235.174	10.2.235.175
60	10.2.235.176/28	10.2.235.177 – 10.2.235.190	10.2.235.191
61	10.2.235.192/28	10.2.235.193 – 10.2.235.206	10.2.235.207
62	10.2.235.208/28	10.2.235.209 – 10.2.235.222	10.2.235.223
63	10.2.235.224/28	10.2.235.225 – 10.2.235.238	10.2.235.239
64	10.2.235.240/28	10.2.235.241 – 10.2.235.254	10.2.235.255
65	10.2.236.0/28	10.2.236.1 – 10.2.236.14	10.2.236.15
66	10.2.236.16/28	10.2.236.17 – 10.2.236.30	10.2.236.31
67	10.2.236.32/28	10.2.236.33 – 10.2.236.46	10.2.236.47
68	10.2.236.48/28	10.2.236.49 – 10.2.236.62	10.2.236.63
69	10.2.236.64/28	10.2.236.65 – 10.2.236.78	10.2.236.79
70	10.2.236.80/28	10.2.236.81 – 10.2.236.94	10.2.236.95
71	10.2.236.96/28	10.2.236.97 – 10.2.236.110	10.2.236.111
72	10.2.236.112/28	10.2.236.113 – 10.2.236.126	10.2.236.127
73	10.2.236.128/28	10.2.236.129 – 10.2.236.142	10.2.236.143
74	10.2.236.144/28	10.2.236.145 – 10.2.236.158	10.2.236.159
75	10.2.236.160/28	10.2.236.161 – 10.2.236.174	10.2.236.175
76	10.2.236.176/28	10.2.236.177 – 10.2.236.190	10.2.236.191
77	10.2.236.192/28	10.2.236.193 – 10.2.236.206	10.2.236.207
78	10.2.236.208/28	10.2.236.209 – 10.2.236.222	10.2.236.223
79	10.2.236.224/28	10.2.236.225 – 10.2.236.238	10.2.236.239
80	10.2.236.240/28	10.2.236.241 – 10.2.236.254	10.2.236.255
81	10.2.237.0/28	10.2.237.1 – 10.2.237.14	10.2.237.15
82	10.2.237.16/28	10.2.237.17 – 10.2.237.30	10.2.237.31
83	10.2.237.32/28	10.2.237.33 – 10.2.237.46	10.2.237.47
84	10.2.237.48/28	10.2.237.49 – 10.2.237.62	10.2.237.63
85	10.2.237.64/28	10.2.237.65 – 10.2.237.78	10.2.237.79
86	10.2.237.80/28	10.2.237.81 – 10.2.237.94	10.2.237.95
87	10.2.237.96/28	10.2.237.97 – 10.2.237.110	10.2.237.111
88	10.2.237.112/28	10.2.237.113 – 10.2.237.126	10.2.237.127
89	10.2.237.128/28	10.2.237.129 – 10.2.237.142	10.2.237.143
90	10.2.237.144/28	10.2.237.145 – 10.2.237.158	10.2.237.159
91	10.2.237.160/28	10.2.237.161 – 10.2.237.174	10.2.237.175
92	10.2.237.176/28	10.2.237.177 – 10.2.237.190	10.2.237.191
93	10.2.237.192/28	10.2.237.193 – 10.2.237.206	10.2.237.207
94	10.2.237.208/28	10.2.237.209 – 10.2.237.222	10.2.237.223
95	10.2.237.224/28	10.2.237.225 – 10.2.237.238	10.2.237.239
96	10.2.237.240/28	10.2.237.241 – 10.2.237.254	10.2.237.255
97	10.2.238.0/28	10.2.238.1 – 10.2.238.14	10.2.238.15
98	10.2.238.16/28	10.2.238.17 – 10.2.238.30	10.2.238.31
99	10.2.238.32/28	10.2.238.33 – 10.2.238.46	10.2.238.47
100	10.2.238.48/28	10.2.238.49 – 10.2.238.62	10.2.238.63
101	10.2.238.64/28	10.2.238.65 – 10.2.238.78	10.2.238.79
102	10.2.238.80/28	10.2.238.81 – 10.2.238.94	10.2.238.95
103	10.2.238.96/28	10.2.238.97 – 10.2.238.110	10.2.238.111
104	10.2.238.112/28	10.2.238.113 – 10.2.238.126	10.2.238.127
105	10.2.238.128/28	10.2.238.129 – 10.2.238.142	10.2.238.143
106	10.2.238.144/28	10.2.238.145 – 10.2.238.158	10.2.238.159
107	10.2.238.160/28	10.2.238.161 – 10.2.238.174	10.2.238.175
108	10.2.238.176/28	10.2.238.177 – 10.2.238.190	10.2.238.191
109	10.2.238.192/28	10.2.238.193 – 10.2.238.206	10.2.238.207
110	10.2.238.208/28	10.2.238.209 – 10.2.238.222	10.2.238.223
111	10.2.238.224/28	10.2.238.225 – 10.2.238.238	10.2.238.239
112	10.2.238.240/28	10.2.238.241 – 10.2.238.254	10.2.238.255
113	10.2.239.0/28	10.2.239.1 – 10.2.239.14	10.2.239.15
114	10.2.239.16/28	10.2.239.17 – 10.2.239.30	10.2.239.31
115	10.2.239.32/28	10.2.239.33 – 10.2.239.46	10.2.239.47
116	10.2.239.48/28	10.2.239.49 – 10.2.239.62	10.2.239.63
117	10.2.239.64/28	10.2.239.65 – 10.2.239.78	10.2.239.79
118	10.2.239.80/28	10.2.239.81 – 10.2.239.94	10.2.239.95
119	10.2.239.96/28	10.2.239.97 – 10.2.239.110	10.2.239.111
120	10.2.239.112/28	10.2.239.113 – 10.2.239.126	10.2.239.127
121	10.2.239.128/28	10.2.239.129 – 10.2.239.142	10.2.239.143
122	10.2.239.144/28	10.2.239.145 – 10.2.239.158	10.2.239.159
123	10.2.239.160/28	10.2.239.161 – 10.2.239.174	10.2.239.175
124	10.2.239.176/28	10.2.239.177 – 10.2.239.190	10.2.239.191
125	10.2.239.192/28	10.2.239.193 – 10.2.239.206	10.2.239.207
126	10.2.239.208/28	10.2.239.209 – 10.2.239.222	10.2.239.223
127	10.2.239.224/28	10.2.239.225 – 10.2.239.238	10.2.239.239
128	10.2.239.240/28	10.2.239.241 – 10.2.239.254	10.2.239.255

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 /21
/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	1
/22	255.255.252.0	1,024	1,022	2 split →
/23	255.255.254.0	512	510	4 split →
/24	255.255.255.0	256	254	8 split →
/25	255.255.255.128	128	126	16 split →
/26	255.255.255.192	64	62	32 split →
/27	255.255.255.224	32	30	64 split →
/28	255.255.255.240	16	14	128 split →
/29	255.255.255.248	8	6	256 split →
/30	255.255.255.252	4	2	512 split →
/31	255.255.255.254	2	2	1,024 split →
/32	255.255.255.255	1	1	2,048 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 →