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)10.78.240.0/20

network10.78.240.0/20

broadcast10.78.255.255

first host10.78.240.1

last host10.78.255.254

subnet mask255.255.240.0

wildcard0.0.15.255

addresses4,096

usable hosts4,094

classA

ipcalc 10.78.240.0/20

address00001010.01001110.11110000.00000000

subnet mask11111111.11111111.11110000.00000000

network00001010.01001110.11110000.00000000

broadcast00001010.01001110.11111111.11111111

green = network part, grey = host part

hex0x0a4ef000

decimal172945408

reverse dns0.240.78.10.in-addr.arpa

ipv4-mapped::ffff:a4e:f000

/20 split into /27 · 128 subnets

close ×

#	network	host range	broadcast
1	10.78.240.0/27	10.78.240.1 – 10.78.240.30	10.78.240.31
2	10.78.240.32/27	10.78.240.33 – 10.78.240.62	10.78.240.63
3	10.78.240.64/27	10.78.240.65 – 10.78.240.94	10.78.240.95
4	10.78.240.96/27	10.78.240.97 – 10.78.240.126	10.78.240.127
5	10.78.240.128/27	10.78.240.129 – 10.78.240.158	10.78.240.159
6	10.78.240.160/27	10.78.240.161 – 10.78.240.190	10.78.240.191
7	10.78.240.192/27	10.78.240.193 – 10.78.240.222	10.78.240.223
8	10.78.240.224/27	10.78.240.225 – 10.78.240.254	10.78.240.255
9	10.78.241.0/27	10.78.241.1 – 10.78.241.30	10.78.241.31
10	10.78.241.32/27	10.78.241.33 – 10.78.241.62	10.78.241.63
11	10.78.241.64/27	10.78.241.65 – 10.78.241.94	10.78.241.95
12	10.78.241.96/27	10.78.241.97 – 10.78.241.126	10.78.241.127
13	10.78.241.128/27	10.78.241.129 – 10.78.241.158	10.78.241.159
14	10.78.241.160/27	10.78.241.161 – 10.78.241.190	10.78.241.191
15	10.78.241.192/27	10.78.241.193 – 10.78.241.222	10.78.241.223
16	10.78.241.224/27	10.78.241.225 – 10.78.241.254	10.78.241.255
17	10.78.242.0/27	10.78.242.1 – 10.78.242.30	10.78.242.31
18	10.78.242.32/27	10.78.242.33 – 10.78.242.62	10.78.242.63
19	10.78.242.64/27	10.78.242.65 – 10.78.242.94	10.78.242.95
20	10.78.242.96/27	10.78.242.97 – 10.78.242.126	10.78.242.127
21	10.78.242.128/27	10.78.242.129 – 10.78.242.158	10.78.242.159
22	10.78.242.160/27	10.78.242.161 – 10.78.242.190	10.78.242.191
23	10.78.242.192/27	10.78.242.193 – 10.78.242.222	10.78.242.223
24	10.78.242.224/27	10.78.242.225 – 10.78.242.254	10.78.242.255
25	10.78.243.0/27	10.78.243.1 – 10.78.243.30	10.78.243.31
26	10.78.243.32/27	10.78.243.33 – 10.78.243.62	10.78.243.63
27	10.78.243.64/27	10.78.243.65 – 10.78.243.94	10.78.243.95
28	10.78.243.96/27	10.78.243.97 – 10.78.243.126	10.78.243.127
29	10.78.243.128/27	10.78.243.129 – 10.78.243.158	10.78.243.159
30	10.78.243.160/27	10.78.243.161 – 10.78.243.190	10.78.243.191
31	10.78.243.192/27	10.78.243.193 – 10.78.243.222	10.78.243.223
32	10.78.243.224/27	10.78.243.225 – 10.78.243.254	10.78.243.255
33	10.78.244.0/27	10.78.244.1 – 10.78.244.30	10.78.244.31
34	10.78.244.32/27	10.78.244.33 – 10.78.244.62	10.78.244.63
35	10.78.244.64/27	10.78.244.65 – 10.78.244.94	10.78.244.95
36	10.78.244.96/27	10.78.244.97 – 10.78.244.126	10.78.244.127
37	10.78.244.128/27	10.78.244.129 – 10.78.244.158	10.78.244.159
38	10.78.244.160/27	10.78.244.161 – 10.78.244.190	10.78.244.191
39	10.78.244.192/27	10.78.244.193 – 10.78.244.222	10.78.244.223
40	10.78.244.224/27	10.78.244.225 – 10.78.244.254	10.78.244.255
41	10.78.245.0/27	10.78.245.1 – 10.78.245.30	10.78.245.31
42	10.78.245.32/27	10.78.245.33 – 10.78.245.62	10.78.245.63
43	10.78.245.64/27	10.78.245.65 – 10.78.245.94	10.78.245.95
44	10.78.245.96/27	10.78.245.97 – 10.78.245.126	10.78.245.127
45	10.78.245.128/27	10.78.245.129 – 10.78.245.158	10.78.245.159
46	10.78.245.160/27	10.78.245.161 – 10.78.245.190	10.78.245.191
47	10.78.245.192/27	10.78.245.193 – 10.78.245.222	10.78.245.223
48	10.78.245.224/27	10.78.245.225 – 10.78.245.254	10.78.245.255
49	10.78.246.0/27	10.78.246.1 – 10.78.246.30	10.78.246.31
50	10.78.246.32/27	10.78.246.33 – 10.78.246.62	10.78.246.63
51	10.78.246.64/27	10.78.246.65 – 10.78.246.94	10.78.246.95
52	10.78.246.96/27	10.78.246.97 – 10.78.246.126	10.78.246.127
53	10.78.246.128/27	10.78.246.129 – 10.78.246.158	10.78.246.159
54	10.78.246.160/27	10.78.246.161 – 10.78.246.190	10.78.246.191
55	10.78.246.192/27	10.78.246.193 – 10.78.246.222	10.78.246.223
56	10.78.246.224/27	10.78.246.225 – 10.78.246.254	10.78.246.255
57	10.78.247.0/27	10.78.247.1 – 10.78.247.30	10.78.247.31
58	10.78.247.32/27	10.78.247.33 – 10.78.247.62	10.78.247.63
59	10.78.247.64/27	10.78.247.65 – 10.78.247.94	10.78.247.95
60	10.78.247.96/27	10.78.247.97 – 10.78.247.126	10.78.247.127
61	10.78.247.128/27	10.78.247.129 – 10.78.247.158	10.78.247.159
62	10.78.247.160/27	10.78.247.161 – 10.78.247.190	10.78.247.191
63	10.78.247.192/27	10.78.247.193 – 10.78.247.222	10.78.247.223
64	10.78.247.224/27	10.78.247.225 – 10.78.247.254	10.78.247.255
65	10.78.248.0/27	10.78.248.1 – 10.78.248.30	10.78.248.31
66	10.78.248.32/27	10.78.248.33 – 10.78.248.62	10.78.248.63
67	10.78.248.64/27	10.78.248.65 – 10.78.248.94	10.78.248.95
68	10.78.248.96/27	10.78.248.97 – 10.78.248.126	10.78.248.127
69	10.78.248.128/27	10.78.248.129 – 10.78.248.158	10.78.248.159
70	10.78.248.160/27	10.78.248.161 – 10.78.248.190	10.78.248.191
71	10.78.248.192/27	10.78.248.193 – 10.78.248.222	10.78.248.223
72	10.78.248.224/27	10.78.248.225 – 10.78.248.254	10.78.248.255
73	10.78.249.0/27	10.78.249.1 – 10.78.249.30	10.78.249.31
74	10.78.249.32/27	10.78.249.33 – 10.78.249.62	10.78.249.63
75	10.78.249.64/27	10.78.249.65 – 10.78.249.94	10.78.249.95
76	10.78.249.96/27	10.78.249.97 – 10.78.249.126	10.78.249.127
77	10.78.249.128/27	10.78.249.129 – 10.78.249.158	10.78.249.159
78	10.78.249.160/27	10.78.249.161 – 10.78.249.190	10.78.249.191
79	10.78.249.192/27	10.78.249.193 – 10.78.249.222	10.78.249.223
80	10.78.249.224/27	10.78.249.225 – 10.78.249.254	10.78.249.255
81	10.78.250.0/27	10.78.250.1 – 10.78.250.30	10.78.250.31
82	10.78.250.32/27	10.78.250.33 – 10.78.250.62	10.78.250.63
83	10.78.250.64/27	10.78.250.65 – 10.78.250.94	10.78.250.95
84	10.78.250.96/27	10.78.250.97 – 10.78.250.126	10.78.250.127
85	10.78.250.128/27	10.78.250.129 – 10.78.250.158	10.78.250.159
86	10.78.250.160/27	10.78.250.161 – 10.78.250.190	10.78.250.191
87	10.78.250.192/27	10.78.250.193 – 10.78.250.222	10.78.250.223
88	10.78.250.224/27	10.78.250.225 – 10.78.250.254	10.78.250.255
89	10.78.251.0/27	10.78.251.1 – 10.78.251.30	10.78.251.31
90	10.78.251.32/27	10.78.251.33 – 10.78.251.62	10.78.251.63
91	10.78.251.64/27	10.78.251.65 – 10.78.251.94	10.78.251.95
92	10.78.251.96/27	10.78.251.97 – 10.78.251.126	10.78.251.127
93	10.78.251.128/27	10.78.251.129 – 10.78.251.158	10.78.251.159
94	10.78.251.160/27	10.78.251.161 – 10.78.251.190	10.78.251.191
95	10.78.251.192/27	10.78.251.193 – 10.78.251.222	10.78.251.223
96	10.78.251.224/27	10.78.251.225 – 10.78.251.254	10.78.251.255
97	10.78.252.0/27	10.78.252.1 – 10.78.252.30	10.78.252.31
98	10.78.252.32/27	10.78.252.33 – 10.78.252.62	10.78.252.63
99	10.78.252.64/27	10.78.252.65 – 10.78.252.94	10.78.252.95
100	10.78.252.96/27	10.78.252.97 – 10.78.252.126	10.78.252.127
101	10.78.252.128/27	10.78.252.129 – 10.78.252.158	10.78.252.159
102	10.78.252.160/27	10.78.252.161 – 10.78.252.190	10.78.252.191
103	10.78.252.192/27	10.78.252.193 – 10.78.252.222	10.78.252.223
104	10.78.252.224/27	10.78.252.225 – 10.78.252.254	10.78.252.255
105	10.78.253.0/27	10.78.253.1 – 10.78.253.30	10.78.253.31
106	10.78.253.32/27	10.78.253.33 – 10.78.253.62	10.78.253.63
107	10.78.253.64/27	10.78.253.65 – 10.78.253.94	10.78.253.95
108	10.78.253.96/27	10.78.253.97 – 10.78.253.126	10.78.253.127
109	10.78.253.128/27	10.78.253.129 – 10.78.253.158	10.78.253.159
110	10.78.253.160/27	10.78.253.161 – 10.78.253.190	10.78.253.191
111	10.78.253.192/27	10.78.253.193 – 10.78.253.222	10.78.253.223
112	10.78.253.224/27	10.78.253.225 – 10.78.253.254	10.78.253.255
113	10.78.254.0/27	10.78.254.1 – 10.78.254.30	10.78.254.31
114	10.78.254.32/27	10.78.254.33 – 10.78.254.62	10.78.254.63
115	10.78.254.64/27	10.78.254.65 – 10.78.254.94	10.78.254.95
116	10.78.254.96/27	10.78.254.97 – 10.78.254.126	10.78.254.127
117	10.78.254.128/27	10.78.254.129 – 10.78.254.158	10.78.254.159
118	10.78.254.160/27	10.78.254.161 – 10.78.254.190	10.78.254.191
119	10.78.254.192/27	10.78.254.193 – 10.78.254.222	10.78.254.223
120	10.78.254.224/27	10.78.254.225 – 10.78.254.254	10.78.254.255
121	10.78.255.0/27	10.78.255.1 – 10.78.255.30	10.78.255.31
122	10.78.255.32/27	10.78.255.33 – 10.78.255.62	10.78.255.63
123	10.78.255.64/27	10.78.255.65 – 10.78.255.94	10.78.255.95
124	10.78.255.96/27	10.78.255.97 – 10.78.255.126	10.78.255.127
125	10.78.255.128/27	10.78.255.129 – 10.78.255.158	10.78.255.159
126	10.78.255.160/27	10.78.255.161 – 10.78.255.190	10.78.255.191
127	10.78.255.192/27	10.78.255.193 – 10.78.255.222	10.78.255.223
128	10.78.255.224/27	10.78.255.225 – 10.78.255.254	10.78.255.255

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 →