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)10.3.208.0/20

network10.3.208.0/20

broadcast10.3.223.255

first host10.3.208.1

last host10.3.223.254

subnet mask255.255.240.0

wildcard0.0.15.255

addresses4,096

usable hosts4,094

classA

ipcalc 10.3.208.0/20

address00001010.00000011.11010000.00000000

subnet mask11111111.11111111.11110000.00000000

network00001010.00000011.11010000.00000000

broadcast00001010.00000011.11011111.11111111

green = network part, grey = host part

hex0x0a03d000

decimal168022016

reverse dns0.208.3.10.in-addr.arpa

ipv4-mapped::ffff:a03:d000

/20 split into /27 · 128 subnets

close ×

#	network	host range	broadcast
1	10.3.208.0/27	10.3.208.1 – 10.3.208.30	10.3.208.31
2	10.3.208.32/27	10.3.208.33 – 10.3.208.62	10.3.208.63
3	10.3.208.64/27	10.3.208.65 – 10.3.208.94	10.3.208.95
4	10.3.208.96/27	10.3.208.97 – 10.3.208.126	10.3.208.127
5	10.3.208.128/27	10.3.208.129 – 10.3.208.158	10.3.208.159
6	10.3.208.160/27	10.3.208.161 – 10.3.208.190	10.3.208.191
7	10.3.208.192/27	10.3.208.193 – 10.3.208.222	10.3.208.223
8	10.3.208.224/27	10.3.208.225 – 10.3.208.254	10.3.208.255
9	10.3.209.0/27	10.3.209.1 – 10.3.209.30	10.3.209.31
10	10.3.209.32/27	10.3.209.33 – 10.3.209.62	10.3.209.63
11	10.3.209.64/27	10.3.209.65 – 10.3.209.94	10.3.209.95
12	10.3.209.96/27	10.3.209.97 – 10.3.209.126	10.3.209.127
13	10.3.209.128/27	10.3.209.129 – 10.3.209.158	10.3.209.159
14	10.3.209.160/27	10.3.209.161 – 10.3.209.190	10.3.209.191
15	10.3.209.192/27	10.3.209.193 – 10.3.209.222	10.3.209.223
16	10.3.209.224/27	10.3.209.225 – 10.3.209.254	10.3.209.255
17	10.3.210.0/27	10.3.210.1 – 10.3.210.30	10.3.210.31
18	10.3.210.32/27	10.3.210.33 – 10.3.210.62	10.3.210.63
19	10.3.210.64/27	10.3.210.65 – 10.3.210.94	10.3.210.95
20	10.3.210.96/27	10.3.210.97 – 10.3.210.126	10.3.210.127
21	10.3.210.128/27	10.3.210.129 – 10.3.210.158	10.3.210.159
22	10.3.210.160/27	10.3.210.161 – 10.3.210.190	10.3.210.191
23	10.3.210.192/27	10.3.210.193 – 10.3.210.222	10.3.210.223
24	10.3.210.224/27	10.3.210.225 – 10.3.210.254	10.3.210.255
25	10.3.211.0/27	10.3.211.1 – 10.3.211.30	10.3.211.31
26	10.3.211.32/27	10.3.211.33 – 10.3.211.62	10.3.211.63
27	10.3.211.64/27	10.3.211.65 – 10.3.211.94	10.3.211.95
28	10.3.211.96/27	10.3.211.97 – 10.3.211.126	10.3.211.127
29	10.3.211.128/27	10.3.211.129 – 10.3.211.158	10.3.211.159
30	10.3.211.160/27	10.3.211.161 – 10.3.211.190	10.3.211.191
31	10.3.211.192/27	10.3.211.193 – 10.3.211.222	10.3.211.223
32	10.3.211.224/27	10.3.211.225 – 10.3.211.254	10.3.211.255
33	10.3.212.0/27	10.3.212.1 – 10.3.212.30	10.3.212.31
34	10.3.212.32/27	10.3.212.33 – 10.3.212.62	10.3.212.63
35	10.3.212.64/27	10.3.212.65 – 10.3.212.94	10.3.212.95
36	10.3.212.96/27	10.3.212.97 – 10.3.212.126	10.3.212.127
37	10.3.212.128/27	10.3.212.129 – 10.3.212.158	10.3.212.159
38	10.3.212.160/27	10.3.212.161 – 10.3.212.190	10.3.212.191
39	10.3.212.192/27	10.3.212.193 – 10.3.212.222	10.3.212.223
40	10.3.212.224/27	10.3.212.225 – 10.3.212.254	10.3.212.255
41	10.3.213.0/27	10.3.213.1 – 10.3.213.30	10.3.213.31
42	10.3.213.32/27	10.3.213.33 – 10.3.213.62	10.3.213.63
43	10.3.213.64/27	10.3.213.65 – 10.3.213.94	10.3.213.95
44	10.3.213.96/27	10.3.213.97 – 10.3.213.126	10.3.213.127
45	10.3.213.128/27	10.3.213.129 – 10.3.213.158	10.3.213.159
46	10.3.213.160/27	10.3.213.161 – 10.3.213.190	10.3.213.191
47	10.3.213.192/27	10.3.213.193 – 10.3.213.222	10.3.213.223
48	10.3.213.224/27	10.3.213.225 – 10.3.213.254	10.3.213.255
49	10.3.214.0/27	10.3.214.1 – 10.3.214.30	10.3.214.31
50	10.3.214.32/27	10.3.214.33 – 10.3.214.62	10.3.214.63
51	10.3.214.64/27	10.3.214.65 – 10.3.214.94	10.3.214.95
52	10.3.214.96/27	10.3.214.97 – 10.3.214.126	10.3.214.127
53	10.3.214.128/27	10.3.214.129 – 10.3.214.158	10.3.214.159
54	10.3.214.160/27	10.3.214.161 – 10.3.214.190	10.3.214.191
55	10.3.214.192/27	10.3.214.193 – 10.3.214.222	10.3.214.223
56	10.3.214.224/27	10.3.214.225 – 10.3.214.254	10.3.214.255
57	10.3.215.0/27	10.3.215.1 – 10.3.215.30	10.3.215.31
58	10.3.215.32/27	10.3.215.33 – 10.3.215.62	10.3.215.63
59	10.3.215.64/27	10.3.215.65 – 10.3.215.94	10.3.215.95
60	10.3.215.96/27	10.3.215.97 – 10.3.215.126	10.3.215.127
61	10.3.215.128/27	10.3.215.129 – 10.3.215.158	10.3.215.159
62	10.3.215.160/27	10.3.215.161 – 10.3.215.190	10.3.215.191
63	10.3.215.192/27	10.3.215.193 – 10.3.215.222	10.3.215.223
64	10.3.215.224/27	10.3.215.225 – 10.3.215.254	10.3.215.255
65	10.3.216.0/27	10.3.216.1 – 10.3.216.30	10.3.216.31
66	10.3.216.32/27	10.3.216.33 – 10.3.216.62	10.3.216.63
67	10.3.216.64/27	10.3.216.65 – 10.3.216.94	10.3.216.95
68	10.3.216.96/27	10.3.216.97 – 10.3.216.126	10.3.216.127
69	10.3.216.128/27	10.3.216.129 – 10.3.216.158	10.3.216.159
70	10.3.216.160/27	10.3.216.161 – 10.3.216.190	10.3.216.191
71	10.3.216.192/27	10.3.216.193 – 10.3.216.222	10.3.216.223
72	10.3.216.224/27	10.3.216.225 – 10.3.216.254	10.3.216.255
73	10.3.217.0/27	10.3.217.1 – 10.3.217.30	10.3.217.31
74	10.3.217.32/27	10.3.217.33 – 10.3.217.62	10.3.217.63
75	10.3.217.64/27	10.3.217.65 – 10.3.217.94	10.3.217.95
76	10.3.217.96/27	10.3.217.97 – 10.3.217.126	10.3.217.127
77	10.3.217.128/27	10.3.217.129 – 10.3.217.158	10.3.217.159
78	10.3.217.160/27	10.3.217.161 – 10.3.217.190	10.3.217.191
79	10.3.217.192/27	10.3.217.193 – 10.3.217.222	10.3.217.223
80	10.3.217.224/27	10.3.217.225 – 10.3.217.254	10.3.217.255
81	10.3.218.0/27	10.3.218.1 – 10.3.218.30	10.3.218.31
82	10.3.218.32/27	10.3.218.33 – 10.3.218.62	10.3.218.63
83	10.3.218.64/27	10.3.218.65 – 10.3.218.94	10.3.218.95
84	10.3.218.96/27	10.3.218.97 – 10.3.218.126	10.3.218.127
85	10.3.218.128/27	10.3.218.129 – 10.3.218.158	10.3.218.159
86	10.3.218.160/27	10.3.218.161 – 10.3.218.190	10.3.218.191
87	10.3.218.192/27	10.3.218.193 – 10.3.218.222	10.3.218.223
88	10.3.218.224/27	10.3.218.225 – 10.3.218.254	10.3.218.255
89	10.3.219.0/27	10.3.219.1 – 10.3.219.30	10.3.219.31
90	10.3.219.32/27	10.3.219.33 – 10.3.219.62	10.3.219.63
91	10.3.219.64/27	10.3.219.65 – 10.3.219.94	10.3.219.95
92	10.3.219.96/27	10.3.219.97 – 10.3.219.126	10.3.219.127
93	10.3.219.128/27	10.3.219.129 – 10.3.219.158	10.3.219.159
94	10.3.219.160/27	10.3.219.161 – 10.3.219.190	10.3.219.191
95	10.3.219.192/27	10.3.219.193 – 10.3.219.222	10.3.219.223
96	10.3.219.224/27	10.3.219.225 – 10.3.219.254	10.3.219.255
97	10.3.220.0/27	10.3.220.1 – 10.3.220.30	10.3.220.31
98	10.3.220.32/27	10.3.220.33 – 10.3.220.62	10.3.220.63
99	10.3.220.64/27	10.3.220.65 – 10.3.220.94	10.3.220.95
100	10.3.220.96/27	10.3.220.97 – 10.3.220.126	10.3.220.127
101	10.3.220.128/27	10.3.220.129 – 10.3.220.158	10.3.220.159
102	10.3.220.160/27	10.3.220.161 – 10.3.220.190	10.3.220.191
103	10.3.220.192/27	10.3.220.193 – 10.3.220.222	10.3.220.223
104	10.3.220.224/27	10.3.220.225 – 10.3.220.254	10.3.220.255
105	10.3.221.0/27	10.3.221.1 – 10.3.221.30	10.3.221.31
106	10.3.221.32/27	10.3.221.33 – 10.3.221.62	10.3.221.63
107	10.3.221.64/27	10.3.221.65 – 10.3.221.94	10.3.221.95
108	10.3.221.96/27	10.3.221.97 – 10.3.221.126	10.3.221.127
109	10.3.221.128/27	10.3.221.129 – 10.3.221.158	10.3.221.159
110	10.3.221.160/27	10.3.221.161 – 10.3.221.190	10.3.221.191
111	10.3.221.192/27	10.3.221.193 – 10.3.221.222	10.3.221.223
112	10.3.221.224/27	10.3.221.225 – 10.3.221.254	10.3.221.255
113	10.3.222.0/27	10.3.222.1 – 10.3.222.30	10.3.222.31
114	10.3.222.32/27	10.3.222.33 – 10.3.222.62	10.3.222.63
115	10.3.222.64/27	10.3.222.65 – 10.3.222.94	10.3.222.95
116	10.3.222.96/27	10.3.222.97 – 10.3.222.126	10.3.222.127
117	10.3.222.128/27	10.3.222.129 – 10.3.222.158	10.3.222.159
118	10.3.222.160/27	10.3.222.161 – 10.3.222.190	10.3.222.191
119	10.3.222.192/27	10.3.222.193 – 10.3.222.222	10.3.222.223
120	10.3.222.224/27	10.3.222.225 – 10.3.222.254	10.3.222.255
121	10.3.223.0/27	10.3.223.1 – 10.3.223.30	10.3.223.31
122	10.3.223.32/27	10.3.223.33 – 10.3.223.62	10.3.223.63
123	10.3.223.64/27	10.3.223.65 – 10.3.223.94	10.3.223.95
124	10.3.223.96/27	10.3.223.97 – 10.3.223.126	10.3.223.127
125	10.3.223.128/27	10.3.223.129 – 10.3.223.158	10.3.223.159
126	10.3.223.160/27	10.3.223.161 – 10.3.223.190	10.3.223.191
127	10.3.223.192/27	10.3.223.193 – 10.3.223.222	10.3.223.223
128	10.3.223.224/27	10.3.223.225 – 10.3.223.254	10.3.223.255

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 /20
/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	1
/21	255.255.248.0	2,048	2,046	2 split →
/22	255.255.252.0	1,024	1,022	4 split →
/23	255.255.254.0	512	510	8 split →
/24	255.255.255.0	256	254	16 split →
/25	255.255.255.128	128	126	32 split →
/26	255.255.255.192	64	62	64 split →
/27	255.255.255.224	32	30	128 split →
/28	255.255.255.240	16	14	256 split →
/29	255.255.255.248	8	6	512 split →
/30	255.255.255.252	4	2	1,024 split →
/31	255.255.255.254	2	2	2,048 split →
/32	255.255.255.255	1	1	4,096 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 →