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)10.3.160.0/21

network10.3.160.0/21

broadcast10.3.167.255

first host10.3.160.1

last host10.3.167.254

subnet mask255.255.248.0

wildcard0.0.7.255

addresses2,048

usable hosts2,046

classA

ipcalc 10.3.160.0/21

address00001010.00000011.10100000.00000000

subnet mask11111111.11111111.11111000.00000000

network00001010.00000011.10100000.00000000

broadcast00001010.00000011.10100111.11111111

green = network part, grey = host part

hex0x0a03a000

decimal168009728

reverse dns0.160.3.10.in-addr.arpa

ipv4-mapped::ffff:a03:a000

/21 split into /28 · 128 subnets

close ×

#	network	host range	broadcast
1	10.3.160.0/28	10.3.160.1 – 10.3.160.14	10.3.160.15
2	10.3.160.16/28	10.3.160.17 – 10.3.160.30	10.3.160.31
3	10.3.160.32/28	10.3.160.33 – 10.3.160.46	10.3.160.47
4	10.3.160.48/28	10.3.160.49 – 10.3.160.62	10.3.160.63
5	10.3.160.64/28	10.3.160.65 – 10.3.160.78	10.3.160.79
6	10.3.160.80/28	10.3.160.81 – 10.3.160.94	10.3.160.95
7	10.3.160.96/28	10.3.160.97 – 10.3.160.110	10.3.160.111
8	10.3.160.112/28	10.3.160.113 – 10.3.160.126	10.3.160.127
9	10.3.160.128/28	10.3.160.129 – 10.3.160.142	10.3.160.143
10	10.3.160.144/28	10.3.160.145 – 10.3.160.158	10.3.160.159
11	10.3.160.160/28	10.3.160.161 – 10.3.160.174	10.3.160.175
12	10.3.160.176/28	10.3.160.177 – 10.3.160.190	10.3.160.191
13	10.3.160.192/28	10.3.160.193 – 10.3.160.206	10.3.160.207
14	10.3.160.208/28	10.3.160.209 – 10.3.160.222	10.3.160.223
15	10.3.160.224/28	10.3.160.225 – 10.3.160.238	10.3.160.239
16	10.3.160.240/28	10.3.160.241 – 10.3.160.254	10.3.160.255
17	10.3.161.0/28	10.3.161.1 – 10.3.161.14	10.3.161.15
18	10.3.161.16/28	10.3.161.17 – 10.3.161.30	10.3.161.31
19	10.3.161.32/28	10.3.161.33 – 10.3.161.46	10.3.161.47
20	10.3.161.48/28	10.3.161.49 – 10.3.161.62	10.3.161.63
21	10.3.161.64/28	10.3.161.65 – 10.3.161.78	10.3.161.79
22	10.3.161.80/28	10.3.161.81 – 10.3.161.94	10.3.161.95
23	10.3.161.96/28	10.3.161.97 – 10.3.161.110	10.3.161.111
24	10.3.161.112/28	10.3.161.113 – 10.3.161.126	10.3.161.127
25	10.3.161.128/28	10.3.161.129 – 10.3.161.142	10.3.161.143
26	10.3.161.144/28	10.3.161.145 – 10.3.161.158	10.3.161.159
27	10.3.161.160/28	10.3.161.161 – 10.3.161.174	10.3.161.175
28	10.3.161.176/28	10.3.161.177 – 10.3.161.190	10.3.161.191
29	10.3.161.192/28	10.3.161.193 – 10.3.161.206	10.3.161.207
30	10.3.161.208/28	10.3.161.209 – 10.3.161.222	10.3.161.223
31	10.3.161.224/28	10.3.161.225 – 10.3.161.238	10.3.161.239
32	10.3.161.240/28	10.3.161.241 – 10.3.161.254	10.3.161.255
33	10.3.162.0/28	10.3.162.1 – 10.3.162.14	10.3.162.15
34	10.3.162.16/28	10.3.162.17 – 10.3.162.30	10.3.162.31
35	10.3.162.32/28	10.3.162.33 – 10.3.162.46	10.3.162.47
36	10.3.162.48/28	10.3.162.49 – 10.3.162.62	10.3.162.63
37	10.3.162.64/28	10.3.162.65 – 10.3.162.78	10.3.162.79
38	10.3.162.80/28	10.3.162.81 – 10.3.162.94	10.3.162.95
39	10.3.162.96/28	10.3.162.97 – 10.3.162.110	10.3.162.111
40	10.3.162.112/28	10.3.162.113 – 10.3.162.126	10.3.162.127
41	10.3.162.128/28	10.3.162.129 – 10.3.162.142	10.3.162.143
42	10.3.162.144/28	10.3.162.145 – 10.3.162.158	10.3.162.159
43	10.3.162.160/28	10.3.162.161 – 10.3.162.174	10.3.162.175
44	10.3.162.176/28	10.3.162.177 – 10.3.162.190	10.3.162.191
45	10.3.162.192/28	10.3.162.193 – 10.3.162.206	10.3.162.207
46	10.3.162.208/28	10.3.162.209 – 10.3.162.222	10.3.162.223
47	10.3.162.224/28	10.3.162.225 – 10.3.162.238	10.3.162.239
48	10.3.162.240/28	10.3.162.241 – 10.3.162.254	10.3.162.255
49	10.3.163.0/28	10.3.163.1 – 10.3.163.14	10.3.163.15
50	10.3.163.16/28	10.3.163.17 – 10.3.163.30	10.3.163.31
51	10.3.163.32/28	10.3.163.33 – 10.3.163.46	10.3.163.47
52	10.3.163.48/28	10.3.163.49 – 10.3.163.62	10.3.163.63
53	10.3.163.64/28	10.3.163.65 – 10.3.163.78	10.3.163.79
54	10.3.163.80/28	10.3.163.81 – 10.3.163.94	10.3.163.95
55	10.3.163.96/28	10.3.163.97 – 10.3.163.110	10.3.163.111
56	10.3.163.112/28	10.3.163.113 – 10.3.163.126	10.3.163.127
57	10.3.163.128/28	10.3.163.129 – 10.3.163.142	10.3.163.143
58	10.3.163.144/28	10.3.163.145 – 10.3.163.158	10.3.163.159
59	10.3.163.160/28	10.3.163.161 – 10.3.163.174	10.3.163.175
60	10.3.163.176/28	10.3.163.177 – 10.3.163.190	10.3.163.191
61	10.3.163.192/28	10.3.163.193 – 10.3.163.206	10.3.163.207
62	10.3.163.208/28	10.3.163.209 – 10.3.163.222	10.3.163.223
63	10.3.163.224/28	10.3.163.225 – 10.3.163.238	10.3.163.239
64	10.3.163.240/28	10.3.163.241 – 10.3.163.254	10.3.163.255
65	10.3.164.0/28	10.3.164.1 – 10.3.164.14	10.3.164.15
66	10.3.164.16/28	10.3.164.17 – 10.3.164.30	10.3.164.31
67	10.3.164.32/28	10.3.164.33 – 10.3.164.46	10.3.164.47
68	10.3.164.48/28	10.3.164.49 – 10.3.164.62	10.3.164.63
69	10.3.164.64/28	10.3.164.65 – 10.3.164.78	10.3.164.79
70	10.3.164.80/28	10.3.164.81 – 10.3.164.94	10.3.164.95
71	10.3.164.96/28	10.3.164.97 – 10.3.164.110	10.3.164.111
72	10.3.164.112/28	10.3.164.113 – 10.3.164.126	10.3.164.127
73	10.3.164.128/28	10.3.164.129 – 10.3.164.142	10.3.164.143
74	10.3.164.144/28	10.3.164.145 – 10.3.164.158	10.3.164.159
75	10.3.164.160/28	10.3.164.161 – 10.3.164.174	10.3.164.175
76	10.3.164.176/28	10.3.164.177 – 10.3.164.190	10.3.164.191
77	10.3.164.192/28	10.3.164.193 – 10.3.164.206	10.3.164.207
78	10.3.164.208/28	10.3.164.209 – 10.3.164.222	10.3.164.223
79	10.3.164.224/28	10.3.164.225 – 10.3.164.238	10.3.164.239
80	10.3.164.240/28	10.3.164.241 – 10.3.164.254	10.3.164.255
81	10.3.165.0/28	10.3.165.1 – 10.3.165.14	10.3.165.15
82	10.3.165.16/28	10.3.165.17 – 10.3.165.30	10.3.165.31
83	10.3.165.32/28	10.3.165.33 – 10.3.165.46	10.3.165.47
84	10.3.165.48/28	10.3.165.49 – 10.3.165.62	10.3.165.63
85	10.3.165.64/28	10.3.165.65 – 10.3.165.78	10.3.165.79
86	10.3.165.80/28	10.3.165.81 – 10.3.165.94	10.3.165.95
87	10.3.165.96/28	10.3.165.97 – 10.3.165.110	10.3.165.111
88	10.3.165.112/28	10.3.165.113 – 10.3.165.126	10.3.165.127
89	10.3.165.128/28	10.3.165.129 – 10.3.165.142	10.3.165.143
90	10.3.165.144/28	10.3.165.145 – 10.3.165.158	10.3.165.159
91	10.3.165.160/28	10.3.165.161 – 10.3.165.174	10.3.165.175
92	10.3.165.176/28	10.3.165.177 – 10.3.165.190	10.3.165.191
93	10.3.165.192/28	10.3.165.193 – 10.3.165.206	10.3.165.207
94	10.3.165.208/28	10.3.165.209 – 10.3.165.222	10.3.165.223
95	10.3.165.224/28	10.3.165.225 – 10.3.165.238	10.3.165.239
96	10.3.165.240/28	10.3.165.241 – 10.3.165.254	10.3.165.255
97	10.3.166.0/28	10.3.166.1 – 10.3.166.14	10.3.166.15
98	10.3.166.16/28	10.3.166.17 – 10.3.166.30	10.3.166.31
99	10.3.166.32/28	10.3.166.33 – 10.3.166.46	10.3.166.47
100	10.3.166.48/28	10.3.166.49 – 10.3.166.62	10.3.166.63
101	10.3.166.64/28	10.3.166.65 – 10.3.166.78	10.3.166.79
102	10.3.166.80/28	10.3.166.81 – 10.3.166.94	10.3.166.95
103	10.3.166.96/28	10.3.166.97 – 10.3.166.110	10.3.166.111
104	10.3.166.112/28	10.3.166.113 – 10.3.166.126	10.3.166.127
105	10.3.166.128/28	10.3.166.129 – 10.3.166.142	10.3.166.143
106	10.3.166.144/28	10.3.166.145 – 10.3.166.158	10.3.166.159
107	10.3.166.160/28	10.3.166.161 – 10.3.166.174	10.3.166.175
108	10.3.166.176/28	10.3.166.177 – 10.3.166.190	10.3.166.191
109	10.3.166.192/28	10.3.166.193 – 10.3.166.206	10.3.166.207
110	10.3.166.208/28	10.3.166.209 – 10.3.166.222	10.3.166.223
111	10.3.166.224/28	10.3.166.225 – 10.3.166.238	10.3.166.239
112	10.3.166.240/28	10.3.166.241 – 10.3.166.254	10.3.166.255
113	10.3.167.0/28	10.3.167.1 – 10.3.167.14	10.3.167.15
114	10.3.167.16/28	10.3.167.17 – 10.3.167.30	10.3.167.31
115	10.3.167.32/28	10.3.167.33 – 10.3.167.46	10.3.167.47
116	10.3.167.48/28	10.3.167.49 – 10.3.167.62	10.3.167.63
117	10.3.167.64/28	10.3.167.65 – 10.3.167.78	10.3.167.79
118	10.3.167.80/28	10.3.167.81 – 10.3.167.94	10.3.167.95
119	10.3.167.96/28	10.3.167.97 – 10.3.167.110	10.3.167.111
120	10.3.167.112/28	10.3.167.113 – 10.3.167.126	10.3.167.127
121	10.3.167.128/28	10.3.167.129 – 10.3.167.142	10.3.167.143
122	10.3.167.144/28	10.3.167.145 – 10.3.167.158	10.3.167.159
123	10.3.167.160/28	10.3.167.161 – 10.3.167.174	10.3.167.175
124	10.3.167.176/28	10.3.167.177 – 10.3.167.190	10.3.167.191
125	10.3.167.192/28	10.3.167.193 – 10.3.167.206	10.3.167.207
126	10.3.167.208/28	10.3.167.209 – 10.3.167.222	10.3.167.223
127	10.3.167.224/28	10.3.167.225 – 10.3.167.238	10.3.167.239
128	10.3.167.240/28	10.3.167.241 – 10.3.167.254	10.3.167.255

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 →