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)10.2.80.0/20

network10.2.80.0/20

broadcast10.2.95.255

first host10.2.80.1

last host10.2.95.254

subnet mask255.255.240.0

wildcard0.0.15.255

addresses4,096

usable hosts4,094

classA

ipcalc 10.2.80.0/20

address00001010.00000010.01010000.00000000

subnet mask11111111.11111111.11110000.00000000

network00001010.00000010.01010000.00000000

broadcast00001010.00000010.01011111.11111111

green = network part, grey = host part

hex0x0a025000

decimal167923712

reverse dns0.80.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:5000

/20 split into /27 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.80.0/27	10.2.80.1 – 10.2.80.30	10.2.80.31
2	10.2.80.32/27	10.2.80.33 – 10.2.80.62	10.2.80.63
3	10.2.80.64/27	10.2.80.65 – 10.2.80.94	10.2.80.95
4	10.2.80.96/27	10.2.80.97 – 10.2.80.126	10.2.80.127
5	10.2.80.128/27	10.2.80.129 – 10.2.80.158	10.2.80.159
6	10.2.80.160/27	10.2.80.161 – 10.2.80.190	10.2.80.191
7	10.2.80.192/27	10.2.80.193 – 10.2.80.222	10.2.80.223
8	10.2.80.224/27	10.2.80.225 – 10.2.80.254	10.2.80.255
9	10.2.81.0/27	10.2.81.1 – 10.2.81.30	10.2.81.31
10	10.2.81.32/27	10.2.81.33 – 10.2.81.62	10.2.81.63
11	10.2.81.64/27	10.2.81.65 – 10.2.81.94	10.2.81.95
12	10.2.81.96/27	10.2.81.97 – 10.2.81.126	10.2.81.127
13	10.2.81.128/27	10.2.81.129 – 10.2.81.158	10.2.81.159
14	10.2.81.160/27	10.2.81.161 – 10.2.81.190	10.2.81.191
15	10.2.81.192/27	10.2.81.193 – 10.2.81.222	10.2.81.223
16	10.2.81.224/27	10.2.81.225 – 10.2.81.254	10.2.81.255
17	10.2.82.0/27	10.2.82.1 – 10.2.82.30	10.2.82.31
18	10.2.82.32/27	10.2.82.33 – 10.2.82.62	10.2.82.63
19	10.2.82.64/27	10.2.82.65 – 10.2.82.94	10.2.82.95
20	10.2.82.96/27	10.2.82.97 – 10.2.82.126	10.2.82.127
21	10.2.82.128/27	10.2.82.129 – 10.2.82.158	10.2.82.159
22	10.2.82.160/27	10.2.82.161 – 10.2.82.190	10.2.82.191
23	10.2.82.192/27	10.2.82.193 – 10.2.82.222	10.2.82.223
24	10.2.82.224/27	10.2.82.225 – 10.2.82.254	10.2.82.255
25	10.2.83.0/27	10.2.83.1 – 10.2.83.30	10.2.83.31
26	10.2.83.32/27	10.2.83.33 – 10.2.83.62	10.2.83.63
27	10.2.83.64/27	10.2.83.65 – 10.2.83.94	10.2.83.95
28	10.2.83.96/27	10.2.83.97 – 10.2.83.126	10.2.83.127
29	10.2.83.128/27	10.2.83.129 – 10.2.83.158	10.2.83.159
30	10.2.83.160/27	10.2.83.161 – 10.2.83.190	10.2.83.191
31	10.2.83.192/27	10.2.83.193 – 10.2.83.222	10.2.83.223
32	10.2.83.224/27	10.2.83.225 – 10.2.83.254	10.2.83.255
33	10.2.84.0/27	10.2.84.1 – 10.2.84.30	10.2.84.31
34	10.2.84.32/27	10.2.84.33 – 10.2.84.62	10.2.84.63
35	10.2.84.64/27	10.2.84.65 – 10.2.84.94	10.2.84.95
36	10.2.84.96/27	10.2.84.97 – 10.2.84.126	10.2.84.127
37	10.2.84.128/27	10.2.84.129 – 10.2.84.158	10.2.84.159
38	10.2.84.160/27	10.2.84.161 – 10.2.84.190	10.2.84.191
39	10.2.84.192/27	10.2.84.193 – 10.2.84.222	10.2.84.223
40	10.2.84.224/27	10.2.84.225 – 10.2.84.254	10.2.84.255
41	10.2.85.0/27	10.2.85.1 – 10.2.85.30	10.2.85.31
42	10.2.85.32/27	10.2.85.33 – 10.2.85.62	10.2.85.63
43	10.2.85.64/27	10.2.85.65 – 10.2.85.94	10.2.85.95
44	10.2.85.96/27	10.2.85.97 – 10.2.85.126	10.2.85.127
45	10.2.85.128/27	10.2.85.129 – 10.2.85.158	10.2.85.159
46	10.2.85.160/27	10.2.85.161 – 10.2.85.190	10.2.85.191
47	10.2.85.192/27	10.2.85.193 – 10.2.85.222	10.2.85.223
48	10.2.85.224/27	10.2.85.225 – 10.2.85.254	10.2.85.255
49	10.2.86.0/27	10.2.86.1 – 10.2.86.30	10.2.86.31
50	10.2.86.32/27	10.2.86.33 – 10.2.86.62	10.2.86.63
51	10.2.86.64/27	10.2.86.65 – 10.2.86.94	10.2.86.95
52	10.2.86.96/27	10.2.86.97 – 10.2.86.126	10.2.86.127
53	10.2.86.128/27	10.2.86.129 – 10.2.86.158	10.2.86.159
54	10.2.86.160/27	10.2.86.161 – 10.2.86.190	10.2.86.191
55	10.2.86.192/27	10.2.86.193 – 10.2.86.222	10.2.86.223
56	10.2.86.224/27	10.2.86.225 – 10.2.86.254	10.2.86.255
57	10.2.87.0/27	10.2.87.1 – 10.2.87.30	10.2.87.31
58	10.2.87.32/27	10.2.87.33 – 10.2.87.62	10.2.87.63
59	10.2.87.64/27	10.2.87.65 – 10.2.87.94	10.2.87.95
60	10.2.87.96/27	10.2.87.97 – 10.2.87.126	10.2.87.127
61	10.2.87.128/27	10.2.87.129 – 10.2.87.158	10.2.87.159
62	10.2.87.160/27	10.2.87.161 – 10.2.87.190	10.2.87.191
63	10.2.87.192/27	10.2.87.193 – 10.2.87.222	10.2.87.223
64	10.2.87.224/27	10.2.87.225 – 10.2.87.254	10.2.87.255
65	10.2.88.0/27	10.2.88.1 – 10.2.88.30	10.2.88.31
66	10.2.88.32/27	10.2.88.33 – 10.2.88.62	10.2.88.63
67	10.2.88.64/27	10.2.88.65 – 10.2.88.94	10.2.88.95
68	10.2.88.96/27	10.2.88.97 – 10.2.88.126	10.2.88.127
69	10.2.88.128/27	10.2.88.129 – 10.2.88.158	10.2.88.159
70	10.2.88.160/27	10.2.88.161 – 10.2.88.190	10.2.88.191
71	10.2.88.192/27	10.2.88.193 – 10.2.88.222	10.2.88.223
72	10.2.88.224/27	10.2.88.225 – 10.2.88.254	10.2.88.255
73	10.2.89.0/27	10.2.89.1 – 10.2.89.30	10.2.89.31
74	10.2.89.32/27	10.2.89.33 – 10.2.89.62	10.2.89.63
75	10.2.89.64/27	10.2.89.65 – 10.2.89.94	10.2.89.95
76	10.2.89.96/27	10.2.89.97 – 10.2.89.126	10.2.89.127
77	10.2.89.128/27	10.2.89.129 – 10.2.89.158	10.2.89.159
78	10.2.89.160/27	10.2.89.161 – 10.2.89.190	10.2.89.191
79	10.2.89.192/27	10.2.89.193 – 10.2.89.222	10.2.89.223
80	10.2.89.224/27	10.2.89.225 – 10.2.89.254	10.2.89.255
81	10.2.90.0/27	10.2.90.1 – 10.2.90.30	10.2.90.31
82	10.2.90.32/27	10.2.90.33 – 10.2.90.62	10.2.90.63
83	10.2.90.64/27	10.2.90.65 – 10.2.90.94	10.2.90.95
84	10.2.90.96/27	10.2.90.97 – 10.2.90.126	10.2.90.127
85	10.2.90.128/27	10.2.90.129 – 10.2.90.158	10.2.90.159
86	10.2.90.160/27	10.2.90.161 – 10.2.90.190	10.2.90.191
87	10.2.90.192/27	10.2.90.193 – 10.2.90.222	10.2.90.223
88	10.2.90.224/27	10.2.90.225 – 10.2.90.254	10.2.90.255
89	10.2.91.0/27	10.2.91.1 – 10.2.91.30	10.2.91.31
90	10.2.91.32/27	10.2.91.33 – 10.2.91.62	10.2.91.63
91	10.2.91.64/27	10.2.91.65 – 10.2.91.94	10.2.91.95
92	10.2.91.96/27	10.2.91.97 – 10.2.91.126	10.2.91.127
93	10.2.91.128/27	10.2.91.129 – 10.2.91.158	10.2.91.159
94	10.2.91.160/27	10.2.91.161 – 10.2.91.190	10.2.91.191
95	10.2.91.192/27	10.2.91.193 – 10.2.91.222	10.2.91.223
96	10.2.91.224/27	10.2.91.225 – 10.2.91.254	10.2.91.255
97	10.2.92.0/27	10.2.92.1 – 10.2.92.30	10.2.92.31
98	10.2.92.32/27	10.2.92.33 – 10.2.92.62	10.2.92.63
99	10.2.92.64/27	10.2.92.65 – 10.2.92.94	10.2.92.95
100	10.2.92.96/27	10.2.92.97 – 10.2.92.126	10.2.92.127
101	10.2.92.128/27	10.2.92.129 – 10.2.92.158	10.2.92.159
102	10.2.92.160/27	10.2.92.161 – 10.2.92.190	10.2.92.191
103	10.2.92.192/27	10.2.92.193 – 10.2.92.222	10.2.92.223
104	10.2.92.224/27	10.2.92.225 – 10.2.92.254	10.2.92.255
105	10.2.93.0/27	10.2.93.1 – 10.2.93.30	10.2.93.31
106	10.2.93.32/27	10.2.93.33 – 10.2.93.62	10.2.93.63
107	10.2.93.64/27	10.2.93.65 – 10.2.93.94	10.2.93.95
108	10.2.93.96/27	10.2.93.97 – 10.2.93.126	10.2.93.127
109	10.2.93.128/27	10.2.93.129 – 10.2.93.158	10.2.93.159
110	10.2.93.160/27	10.2.93.161 – 10.2.93.190	10.2.93.191
111	10.2.93.192/27	10.2.93.193 – 10.2.93.222	10.2.93.223
112	10.2.93.224/27	10.2.93.225 – 10.2.93.254	10.2.93.255
113	10.2.94.0/27	10.2.94.1 – 10.2.94.30	10.2.94.31
114	10.2.94.32/27	10.2.94.33 – 10.2.94.62	10.2.94.63
115	10.2.94.64/27	10.2.94.65 – 10.2.94.94	10.2.94.95
116	10.2.94.96/27	10.2.94.97 – 10.2.94.126	10.2.94.127
117	10.2.94.128/27	10.2.94.129 – 10.2.94.158	10.2.94.159
118	10.2.94.160/27	10.2.94.161 – 10.2.94.190	10.2.94.191
119	10.2.94.192/27	10.2.94.193 – 10.2.94.222	10.2.94.223
120	10.2.94.224/27	10.2.94.225 – 10.2.94.254	10.2.94.255
121	10.2.95.0/27	10.2.95.1 – 10.2.95.30	10.2.95.31
122	10.2.95.32/27	10.2.95.33 – 10.2.95.62	10.2.95.63
123	10.2.95.64/27	10.2.95.65 – 10.2.95.94	10.2.95.95
124	10.2.95.96/27	10.2.95.97 – 10.2.95.126	10.2.95.127
125	10.2.95.128/27	10.2.95.129 – 10.2.95.158	10.2.95.159
126	10.2.95.160/27	10.2.95.161 – 10.2.95.190	10.2.95.191
127	10.2.95.192/27	10.2.95.193 – 10.2.95.222	10.2.95.223
128	10.2.95.224/27	10.2.95.225 – 10.2.95.254	10.2.95.255

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 →