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)10.3.64.0/20

network10.3.64.0/20

broadcast10.3.79.255

first host10.3.64.1

last host10.3.79.254

subnet mask255.255.240.0

wildcard0.0.15.255

addresses4,096

usable hosts4,094

classA

ipcalc 10.3.64.0/20

address00001010.00000011.01000000.00000000

subnet mask11111111.11111111.11110000.00000000

network00001010.00000011.01000000.00000000

broadcast00001010.00000011.01001111.11111111

green = network part, grey = host part

hex0x0a034000

decimal167985152

reverse dns0.64.3.10.in-addr.arpa

ipv4-mapped::ffff:a03:4000

/20 split into /27 · 128 subnets

close ×

#	network	host range	broadcast
1	10.3.64.0/27	10.3.64.1 – 10.3.64.30	10.3.64.31
2	10.3.64.32/27	10.3.64.33 – 10.3.64.62	10.3.64.63
3	10.3.64.64/27	10.3.64.65 – 10.3.64.94	10.3.64.95
4	10.3.64.96/27	10.3.64.97 – 10.3.64.126	10.3.64.127
5	10.3.64.128/27	10.3.64.129 – 10.3.64.158	10.3.64.159
6	10.3.64.160/27	10.3.64.161 – 10.3.64.190	10.3.64.191
7	10.3.64.192/27	10.3.64.193 – 10.3.64.222	10.3.64.223
8	10.3.64.224/27	10.3.64.225 – 10.3.64.254	10.3.64.255
9	10.3.65.0/27	10.3.65.1 – 10.3.65.30	10.3.65.31
10	10.3.65.32/27	10.3.65.33 – 10.3.65.62	10.3.65.63
11	10.3.65.64/27	10.3.65.65 – 10.3.65.94	10.3.65.95
12	10.3.65.96/27	10.3.65.97 – 10.3.65.126	10.3.65.127
13	10.3.65.128/27	10.3.65.129 – 10.3.65.158	10.3.65.159
14	10.3.65.160/27	10.3.65.161 – 10.3.65.190	10.3.65.191
15	10.3.65.192/27	10.3.65.193 – 10.3.65.222	10.3.65.223
16	10.3.65.224/27	10.3.65.225 – 10.3.65.254	10.3.65.255
17	10.3.66.0/27	10.3.66.1 – 10.3.66.30	10.3.66.31
18	10.3.66.32/27	10.3.66.33 – 10.3.66.62	10.3.66.63
19	10.3.66.64/27	10.3.66.65 – 10.3.66.94	10.3.66.95
20	10.3.66.96/27	10.3.66.97 – 10.3.66.126	10.3.66.127
21	10.3.66.128/27	10.3.66.129 – 10.3.66.158	10.3.66.159
22	10.3.66.160/27	10.3.66.161 – 10.3.66.190	10.3.66.191
23	10.3.66.192/27	10.3.66.193 – 10.3.66.222	10.3.66.223
24	10.3.66.224/27	10.3.66.225 – 10.3.66.254	10.3.66.255
25	10.3.67.0/27	10.3.67.1 – 10.3.67.30	10.3.67.31
26	10.3.67.32/27	10.3.67.33 – 10.3.67.62	10.3.67.63
27	10.3.67.64/27	10.3.67.65 – 10.3.67.94	10.3.67.95
28	10.3.67.96/27	10.3.67.97 – 10.3.67.126	10.3.67.127
29	10.3.67.128/27	10.3.67.129 – 10.3.67.158	10.3.67.159
30	10.3.67.160/27	10.3.67.161 – 10.3.67.190	10.3.67.191
31	10.3.67.192/27	10.3.67.193 – 10.3.67.222	10.3.67.223
32	10.3.67.224/27	10.3.67.225 – 10.3.67.254	10.3.67.255
33	10.3.68.0/27	10.3.68.1 – 10.3.68.30	10.3.68.31
34	10.3.68.32/27	10.3.68.33 – 10.3.68.62	10.3.68.63
35	10.3.68.64/27	10.3.68.65 – 10.3.68.94	10.3.68.95
36	10.3.68.96/27	10.3.68.97 – 10.3.68.126	10.3.68.127
37	10.3.68.128/27	10.3.68.129 – 10.3.68.158	10.3.68.159
38	10.3.68.160/27	10.3.68.161 – 10.3.68.190	10.3.68.191
39	10.3.68.192/27	10.3.68.193 – 10.3.68.222	10.3.68.223
40	10.3.68.224/27	10.3.68.225 – 10.3.68.254	10.3.68.255
41	10.3.69.0/27	10.3.69.1 – 10.3.69.30	10.3.69.31
42	10.3.69.32/27	10.3.69.33 – 10.3.69.62	10.3.69.63
43	10.3.69.64/27	10.3.69.65 – 10.3.69.94	10.3.69.95
44	10.3.69.96/27	10.3.69.97 – 10.3.69.126	10.3.69.127
45	10.3.69.128/27	10.3.69.129 – 10.3.69.158	10.3.69.159
46	10.3.69.160/27	10.3.69.161 – 10.3.69.190	10.3.69.191
47	10.3.69.192/27	10.3.69.193 – 10.3.69.222	10.3.69.223
48	10.3.69.224/27	10.3.69.225 – 10.3.69.254	10.3.69.255
49	10.3.70.0/27	10.3.70.1 – 10.3.70.30	10.3.70.31
50	10.3.70.32/27	10.3.70.33 – 10.3.70.62	10.3.70.63
51	10.3.70.64/27	10.3.70.65 – 10.3.70.94	10.3.70.95
52	10.3.70.96/27	10.3.70.97 – 10.3.70.126	10.3.70.127
53	10.3.70.128/27	10.3.70.129 – 10.3.70.158	10.3.70.159
54	10.3.70.160/27	10.3.70.161 – 10.3.70.190	10.3.70.191
55	10.3.70.192/27	10.3.70.193 – 10.3.70.222	10.3.70.223
56	10.3.70.224/27	10.3.70.225 – 10.3.70.254	10.3.70.255
57	10.3.71.0/27	10.3.71.1 – 10.3.71.30	10.3.71.31
58	10.3.71.32/27	10.3.71.33 – 10.3.71.62	10.3.71.63
59	10.3.71.64/27	10.3.71.65 – 10.3.71.94	10.3.71.95
60	10.3.71.96/27	10.3.71.97 – 10.3.71.126	10.3.71.127
61	10.3.71.128/27	10.3.71.129 – 10.3.71.158	10.3.71.159
62	10.3.71.160/27	10.3.71.161 – 10.3.71.190	10.3.71.191
63	10.3.71.192/27	10.3.71.193 – 10.3.71.222	10.3.71.223
64	10.3.71.224/27	10.3.71.225 – 10.3.71.254	10.3.71.255
65	10.3.72.0/27	10.3.72.1 – 10.3.72.30	10.3.72.31
66	10.3.72.32/27	10.3.72.33 – 10.3.72.62	10.3.72.63
67	10.3.72.64/27	10.3.72.65 – 10.3.72.94	10.3.72.95
68	10.3.72.96/27	10.3.72.97 – 10.3.72.126	10.3.72.127
69	10.3.72.128/27	10.3.72.129 – 10.3.72.158	10.3.72.159
70	10.3.72.160/27	10.3.72.161 – 10.3.72.190	10.3.72.191
71	10.3.72.192/27	10.3.72.193 – 10.3.72.222	10.3.72.223
72	10.3.72.224/27	10.3.72.225 – 10.3.72.254	10.3.72.255
73	10.3.73.0/27	10.3.73.1 – 10.3.73.30	10.3.73.31
74	10.3.73.32/27	10.3.73.33 – 10.3.73.62	10.3.73.63
75	10.3.73.64/27	10.3.73.65 – 10.3.73.94	10.3.73.95
76	10.3.73.96/27	10.3.73.97 – 10.3.73.126	10.3.73.127
77	10.3.73.128/27	10.3.73.129 – 10.3.73.158	10.3.73.159
78	10.3.73.160/27	10.3.73.161 – 10.3.73.190	10.3.73.191
79	10.3.73.192/27	10.3.73.193 – 10.3.73.222	10.3.73.223
80	10.3.73.224/27	10.3.73.225 – 10.3.73.254	10.3.73.255
81	10.3.74.0/27	10.3.74.1 – 10.3.74.30	10.3.74.31
82	10.3.74.32/27	10.3.74.33 – 10.3.74.62	10.3.74.63
83	10.3.74.64/27	10.3.74.65 – 10.3.74.94	10.3.74.95
84	10.3.74.96/27	10.3.74.97 – 10.3.74.126	10.3.74.127
85	10.3.74.128/27	10.3.74.129 – 10.3.74.158	10.3.74.159
86	10.3.74.160/27	10.3.74.161 – 10.3.74.190	10.3.74.191
87	10.3.74.192/27	10.3.74.193 – 10.3.74.222	10.3.74.223
88	10.3.74.224/27	10.3.74.225 – 10.3.74.254	10.3.74.255
89	10.3.75.0/27	10.3.75.1 – 10.3.75.30	10.3.75.31
90	10.3.75.32/27	10.3.75.33 – 10.3.75.62	10.3.75.63
91	10.3.75.64/27	10.3.75.65 – 10.3.75.94	10.3.75.95
92	10.3.75.96/27	10.3.75.97 – 10.3.75.126	10.3.75.127
93	10.3.75.128/27	10.3.75.129 – 10.3.75.158	10.3.75.159
94	10.3.75.160/27	10.3.75.161 – 10.3.75.190	10.3.75.191
95	10.3.75.192/27	10.3.75.193 – 10.3.75.222	10.3.75.223
96	10.3.75.224/27	10.3.75.225 – 10.3.75.254	10.3.75.255
97	10.3.76.0/27	10.3.76.1 – 10.3.76.30	10.3.76.31
98	10.3.76.32/27	10.3.76.33 – 10.3.76.62	10.3.76.63
99	10.3.76.64/27	10.3.76.65 – 10.3.76.94	10.3.76.95
100	10.3.76.96/27	10.3.76.97 – 10.3.76.126	10.3.76.127
101	10.3.76.128/27	10.3.76.129 – 10.3.76.158	10.3.76.159
102	10.3.76.160/27	10.3.76.161 – 10.3.76.190	10.3.76.191
103	10.3.76.192/27	10.3.76.193 – 10.3.76.222	10.3.76.223
104	10.3.76.224/27	10.3.76.225 – 10.3.76.254	10.3.76.255
105	10.3.77.0/27	10.3.77.1 – 10.3.77.30	10.3.77.31
106	10.3.77.32/27	10.3.77.33 – 10.3.77.62	10.3.77.63
107	10.3.77.64/27	10.3.77.65 – 10.3.77.94	10.3.77.95
108	10.3.77.96/27	10.3.77.97 – 10.3.77.126	10.3.77.127
109	10.3.77.128/27	10.3.77.129 – 10.3.77.158	10.3.77.159
110	10.3.77.160/27	10.3.77.161 – 10.3.77.190	10.3.77.191
111	10.3.77.192/27	10.3.77.193 – 10.3.77.222	10.3.77.223
112	10.3.77.224/27	10.3.77.225 – 10.3.77.254	10.3.77.255
113	10.3.78.0/27	10.3.78.1 – 10.3.78.30	10.3.78.31
114	10.3.78.32/27	10.3.78.33 – 10.3.78.62	10.3.78.63
115	10.3.78.64/27	10.3.78.65 – 10.3.78.94	10.3.78.95
116	10.3.78.96/27	10.3.78.97 – 10.3.78.126	10.3.78.127
117	10.3.78.128/27	10.3.78.129 – 10.3.78.158	10.3.78.159
118	10.3.78.160/27	10.3.78.161 – 10.3.78.190	10.3.78.191
119	10.3.78.192/27	10.3.78.193 – 10.3.78.222	10.3.78.223
120	10.3.78.224/27	10.3.78.225 – 10.3.78.254	10.3.78.255
121	10.3.79.0/27	10.3.79.1 – 10.3.79.30	10.3.79.31
122	10.3.79.32/27	10.3.79.33 – 10.3.79.62	10.3.79.63
123	10.3.79.64/27	10.3.79.65 – 10.3.79.94	10.3.79.95
124	10.3.79.96/27	10.3.79.97 – 10.3.79.126	10.3.79.127
125	10.3.79.128/27	10.3.79.129 – 10.3.79.158	10.3.79.159
126	10.3.79.160/27	10.3.79.161 – 10.3.79.190	10.3.79.191
127	10.3.79.192/27	10.3.79.193 – 10.3.79.222	10.3.79.223
128	10.3.79.224/27	10.3.79.225 – 10.3.79.254	10.3.79.255

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 →