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)10.71.64.0/18

network10.71.64.0/18

broadcast10.71.127.255

first host10.71.64.1

last host10.71.127.254

subnet mask255.255.192.0

wildcard0.0.63.255

addresses16,384

usable hosts16,382

classA

ipcalc 10.71.64.0/18

address00001010.01000111.01000000.00000000

subnet mask11111111.11111111.11000000.00000000

network00001010.01000111.01000000.00000000

broadcast00001010.01000111.01111111.11111111

green = network part, grey = host part

hex0x0a474000

decimal172441600

reverse dns0.64.71.10.in-addr.arpa

ipv4-mapped::ffff:a47:4000

/18 split into /25 · 128 subnets

close ×

#	network	host range	broadcast
1	10.71.64.0/25	10.71.64.1 – 10.71.64.126	10.71.64.127
2	10.71.64.128/25	10.71.64.129 – 10.71.64.254	10.71.64.255
3	10.71.65.0/25	10.71.65.1 – 10.71.65.126	10.71.65.127
4	10.71.65.128/25	10.71.65.129 – 10.71.65.254	10.71.65.255
5	10.71.66.0/25	10.71.66.1 – 10.71.66.126	10.71.66.127
6	10.71.66.128/25	10.71.66.129 – 10.71.66.254	10.71.66.255
7	10.71.67.0/25	10.71.67.1 – 10.71.67.126	10.71.67.127
8	10.71.67.128/25	10.71.67.129 – 10.71.67.254	10.71.67.255
9	10.71.68.0/25	10.71.68.1 – 10.71.68.126	10.71.68.127
10	10.71.68.128/25	10.71.68.129 – 10.71.68.254	10.71.68.255
11	10.71.69.0/25	10.71.69.1 – 10.71.69.126	10.71.69.127
12	10.71.69.128/25	10.71.69.129 – 10.71.69.254	10.71.69.255
13	10.71.70.0/25	10.71.70.1 – 10.71.70.126	10.71.70.127
14	10.71.70.128/25	10.71.70.129 – 10.71.70.254	10.71.70.255
15	10.71.71.0/25	10.71.71.1 – 10.71.71.126	10.71.71.127
16	10.71.71.128/25	10.71.71.129 – 10.71.71.254	10.71.71.255
17	10.71.72.0/25	10.71.72.1 – 10.71.72.126	10.71.72.127
18	10.71.72.128/25	10.71.72.129 – 10.71.72.254	10.71.72.255
19	10.71.73.0/25	10.71.73.1 – 10.71.73.126	10.71.73.127
20	10.71.73.128/25	10.71.73.129 – 10.71.73.254	10.71.73.255
21	10.71.74.0/25	10.71.74.1 – 10.71.74.126	10.71.74.127
22	10.71.74.128/25	10.71.74.129 – 10.71.74.254	10.71.74.255
23	10.71.75.0/25	10.71.75.1 – 10.71.75.126	10.71.75.127
24	10.71.75.128/25	10.71.75.129 – 10.71.75.254	10.71.75.255
25	10.71.76.0/25	10.71.76.1 – 10.71.76.126	10.71.76.127
26	10.71.76.128/25	10.71.76.129 – 10.71.76.254	10.71.76.255
27	10.71.77.0/25	10.71.77.1 – 10.71.77.126	10.71.77.127
28	10.71.77.128/25	10.71.77.129 – 10.71.77.254	10.71.77.255
29	10.71.78.0/25	10.71.78.1 – 10.71.78.126	10.71.78.127
30	10.71.78.128/25	10.71.78.129 – 10.71.78.254	10.71.78.255
31	10.71.79.0/25	10.71.79.1 – 10.71.79.126	10.71.79.127
32	10.71.79.128/25	10.71.79.129 – 10.71.79.254	10.71.79.255
33	10.71.80.0/25	10.71.80.1 – 10.71.80.126	10.71.80.127
34	10.71.80.128/25	10.71.80.129 – 10.71.80.254	10.71.80.255
35	10.71.81.0/25	10.71.81.1 – 10.71.81.126	10.71.81.127
36	10.71.81.128/25	10.71.81.129 – 10.71.81.254	10.71.81.255
37	10.71.82.0/25	10.71.82.1 – 10.71.82.126	10.71.82.127
38	10.71.82.128/25	10.71.82.129 – 10.71.82.254	10.71.82.255
39	10.71.83.0/25	10.71.83.1 – 10.71.83.126	10.71.83.127
40	10.71.83.128/25	10.71.83.129 – 10.71.83.254	10.71.83.255
41	10.71.84.0/25	10.71.84.1 – 10.71.84.126	10.71.84.127
42	10.71.84.128/25	10.71.84.129 – 10.71.84.254	10.71.84.255
43	10.71.85.0/25	10.71.85.1 – 10.71.85.126	10.71.85.127
44	10.71.85.128/25	10.71.85.129 – 10.71.85.254	10.71.85.255
45	10.71.86.0/25	10.71.86.1 – 10.71.86.126	10.71.86.127
46	10.71.86.128/25	10.71.86.129 – 10.71.86.254	10.71.86.255
47	10.71.87.0/25	10.71.87.1 – 10.71.87.126	10.71.87.127
48	10.71.87.128/25	10.71.87.129 – 10.71.87.254	10.71.87.255
49	10.71.88.0/25	10.71.88.1 – 10.71.88.126	10.71.88.127
50	10.71.88.128/25	10.71.88.129 – 10.71.88.254	10.71.88.255
51	10.71.89.0/25	10.71.89.1 – 10.71.89.126	10.71.89.127
52	10.71.89.128/25	10.71.89.129 – 10.71.89.254	10.71.89.255
53	10.71.90.0/25	10.71.90.1 – 10.71.90.126	10.71.90.127
54	10.71.90.128/25	10.71.90.129 – 10.71.90.254	10.71.90.255
55	10.71.91.0/25	10.71.91.1 – 10.71.91.126	10.71.91.127
56	10.71.91.128/25	10.71.91.129 – 10.71.91.254	10.71.91.255
57	10.71.92.0/25	10.71.92.1 – 10.71.92.126	10.71.92.127
58	10.71.92.128/25	10.71.92.129 – 10.71.92.254	10.71.92.255
59	10.71.93.0/25	10.71.93.1 – 10.71.93.126	10.71.93.127
60	10.71.93.128/25	10.71.93.129 – 10.71.93.254	10.71.93.255
61	10.71.94.0/25	10.71.94.1 – 10.71.94.126	10.71.94.127
62	10.71.94.128/25	10.71.94.129 – 10.71.94.254	10.71.94.255
63	10.71.95.0/25	10.71.95.1 – 10.71.95.126	10.71.95.127
64	10.71.95.128/25	10.71.95.129 – 10.71.95.254	10.71.95.255
65	10.71.96.0/25	10.71.96.1 – 10.71.96.126	10.71.96.127
66	10.71.96.128/25	10.71.96.129 – 10.71.96.254	10.71.96.255
67	10.71.97.0/25	10.71.97.1 – 10.71.97.126	10.71.97.127
68	10.71.97.128/25	10.71.97.129 – 10.71.97.254	10.71.97.255
69	10.71.98.0/25	10.71.98.1 – 10.71.98.126	10.71.98.127
70	10.71.98.128/25	10.71.98.129 – 10.71.98.254	10.71.98.255
71	10.71.99.0/25	10.71.99.1 – 10.71.99.126	10.71.99.127
72	10.71.99.128/25	10.71.99.129 – 10.71.99.254	10.71.99.255
73	10.71.100.0/25	10.71.100.1 – 10.71.100.126	10.71.100.127
74	10.71.100.128/25	10.71.100.129 – 10.71.100.254	10.71.100.255
75	10.71.101.0/25	10.71.101.1 – 10.71.101.126	10.71.101.127
76	10.71.101.128/25	10.71.101.129 – 10.71.101.254	10.71.101.255
77	10.71.102.0/25	10.71.102.1 – 10.71.102.126	10.71.102.127
78	10.71.102.128/25	10.71.102.129 – 10.71.102.254	10.71.102.255
79	10.71.103.0/25	10.71.103.1 – 10.71.103.126	10.71.103.127
80	10.71.103.128/25	10.71.103.129 – 10.71.103.254	10.71.103.255
81	10.71.104.0/25	10.71.104.1 – 10.71.104.126	10.71.104.127
82	10.71.104.128/25	10.71.104.129 – 10.71.104.254	10.71.104.255
83	10.71.105.0/25	10.71.105.1 – 10.71.105.126	10.71.105.127
84	10.71.105.128/25	10.71.105.129 – 10.71.105.254	10.71.105.255
85	10.71.106.0/25	10.71.106.1 – 10.71.106.126	10.71.106.127
86	10.71.106.128/25	10.71.106.129 – 10.71.106.254	10.71.106.255
87	10.71.107.0/25	10.71.107.1 – 10.71.107.126	10.71.107.127
88	10.71.107.128/25	10.71.107.129 – 10.71.107.254	10.71.107.255
89	10.71.108.0/25	10.71.108.1 – 10.71.108.126	10.71.108.127
90	10.71.108.128/25	10.71.108.129 – 10.71.108.254	10.71.108.255
91	10.71.109.0/25	10.71.109.1 – 10.71.109.126	10.71.109.127
92	10.71.109.128/25	10.71.109.129 – 10.71.109.254	10.71.109.255
93	10.71.110.0/25	10.71.110.1 – 10.71.110.126	10.71.110.127
94	10.71.110.128/25	10.71.110.129 – 10.71.110.254	10.71.110.255
95	10.71.111.0/25	10.71.111.1 – 10.71.111.126	10.71.111.127
96	10.71.111.128/25	10.71.111.129 – 10.71.111.254	10.71.111.255
97	10.71.112.0/25	10.71.112.1 – 10.71.112.126	10.71.112.127
98	10.71.112.128/25	10.71.112.129 – 10.71.112.254	10.71.112.255
99	10.71.113.0/25	10.71.113.1 – 10.71.113.126	10.71.113.127
100	10.71.113.128/25	10.71.113.129 – 10.71.113.254	10.71.113.255
101	10.71.114.0/25	10.71.114.1 – 10.71.114.126	10.71.114.127
102	10.71.114.128/25	10.71.114.129 – 10.71.114.254	10.71.114.255
103	10.71.115.0/25	10.71.115.1 – 10.71.115.126	10.71.115.127
104	10.71.115.128/25	10.71.115.129 – 10.71.115.254	10.71.115.255
105	10.71.116.0/25	10.71.116.1 – 10.71.116.126	10.71.116.127
106	10.71.116.128/25	10.71.116.129 – 10.71.116.254	10.71.116.255
107	10.71.117.0/25	10.71.117.1 – 10.71.117.126	10.71.117.127
108	10.71.117.128/25	10.71.117.129 – 10.71.117.254	10.71.117.255
109	10.71.118.0/25	10.71.118.1 – 10.71.118.126	10.71.118.127
110	10.71.118.128/25	10.71.118.129 – 10.71.118.254	10.71.118.255
111	10.71.119.0/25	10.71.119.1 – 10.71.119.126	10.71.119.127
112	10.71.119.128/25	10.71.119.129 – 10.71.119.254	10.71.119.255
113	10.71.120.0/25	10.71.120.1 – 10.71.120.126	10.71.120.127
114	10.71.120.128/25	10.71.120.129 – 10.71.120.254	10.71.120.255
115	10.71.121.0/25	10.71.121.1 – 10.71.121.126	10.71.121.127
116	10.71.121.128/25	10.71.121.129 – 10.71.121.254	10.71.121.255
117	10.71.122.0/25	10.71.122.1 – 10.71.122.126	10.71.122.127
118	10.71.122.128/25	10.71.122.129 – 10.71.122.254	10.71.122.255
119	10.71.123.0/25	10.71.123.1 – 10.71.123.126	10.71.123.127
120	10.71.123.128/25	10.71.123.129 – 10.71.123.254	10.71.123.255
121	10.71.124.0/25	10.71.124.1 – 10.71.124.126	10.71.124.127
122	10.71.124.128/25	10.71.124.129 – 10.71.124.254	10.71.124.255
123	10.71.125.0/25	10.71.125.1 – 10.71.125.126	10.71.125.127
124	10.71.125.128/25	10.71.125.129 – 10.71.125.254	10.71.125.255
125	10.71.126.0/25	10.71.126.1 – 10.71.126.126	10.71.126.127
126	10.71.126.128/25	10.71.126.129 – 10.71.126.254	10.71.126.255
127	10.71.127.0/25	10.71.127.1 – 10.71.127.126	10.71.127.127
128	10.71.127.128/25	10.71.127.129 – 10.71.127.254	10.71.127.255

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 /18
/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	1
/19	255.255.224.0	8,192	8,190	2 split →
/20	255.255.240.0	4,096	4,094	4 split →
/21	255.255.248.0	2,048	2,046	8 split →
/22	255.255.252.0	1,024	1,022	16 split →
/23	255.255.254.0	512	510	32 split →
/24	255.255.255.0	256	254	64 split →
/25	255.255.255.128	128	126	128 split →
/26	255.255.255.192	64	62	256 split →
/27	255.255.255.224	32	30	512 split →
/28	255.255.255.240	16	14	1,024 split →
/29	255.255.255.248	8	6	2,048 split →
/30	255.255.255.252	4	2	4,096 split →
/31	255.255.255.254	2	2	8,192 split →
/32	255.255.255.255	1	1	16,384 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 →