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)10.31.32.0/19

network10.31.32.0/19

broadcast10.31.63.255

first host10.31.32.1

last host10.31.63.254

subnet mask255.255.224.0

wildcard0.0.31.255

addresses8,192

usable hosts8,190

classA

ipcalc 10.31.32.0/19

address00001010.00011111.00100000.00000000

subnet mask11111111.11111111.11100000.00000000

network00001010.00011111.00100000.00000000

broadcast00001010.00011111.00111111.11111111

green = network part, grey = host part

hex0x0a1f2000

decimal169811968

reverse dns0.32.31.10.in-addr.arpa

ipv4-mapped::ffff:a1f:2000

/19 split into /26 · 128 subnets

close ×

#	network	host range	broadcast
1	10.31.32.0/26	10.31.32.1 – 10.31.32.62	10.31.32.63
2	10.31.32.64/26	10.31.32.65 – 10.31.32.126	10.31.32.127
3	10.31.32.128/26	10.31.32.129 – 10.31.32.190	10.31.32.191
4	10.31.32.192/26	10.31.32.193 – 10.31.32.254	10.31.32.255
5	10.31.33.0/26	10.31.33.1 – 10.31.33.62	10.31.33.63
6	10.31.33.64/26	10.31.33.65 – 10.31.33.126	10.31.33.127
7	10.31.33.128/26	10.31.33.129 – 10.31.33.190	10.31.33.191
8	10.31.33.192/26	10.31.33.193 – 10.31.33.254	10.31.33.255
9	10.31.34.0/26	10.31.34.1 – 10.31.34.62	10.31.34.63
10	10.31.34.64/26	10.31.34.65 – 10.31.34.126	10.31.34.127
11	10.31.34.128/26	10.31.34.129 – 10.31.34.190	10.31.34.191
12	10.31.34.192/26	10.31.34.193 – 10.31.34.254	10.31.34.255
13	10.31.35.0/26	10.31.35.1 – 10.31.35.62	10.31.35.63
14	10.31.35.64/26	10.31.35.65 – 10.31.35.126	10.31.35.127
15	10.31.35.128/26	10.31.35.129 – 10.31.35.190	10.31.35.191
16	10.31.35.192/26	10.31.35.193 – 10.31.35.254	10.31.35.255
17	10.31.36.0/26	10.31.36.1 – 10.31.36.62	10.31.36.63
18	10.31.36.64/26	10.31.36.65 – 10.31.36.126	10.31.36.127
19	10.31.36.128/26	10.31.36.129 – 10.31.36.190	10.31.36.191
20	10.31.36.192/26	10.31.36.193 – 10.31.36.254	10.31.36.255
21	10.31.37.0/26	10.31.37.1 – 10.31.37.62	10.31.37.63
22	10.31.37.64/26	10.31.37.65 – 10.31.37.126	10.31.37.127
23	10.31.37.128/26	10.31.37.129 – 10.31.37.190	10.31.37.191
24	10.31.37.192/26	10.31.37.193 – 10.31.37.254	10.31.37.255
25	10.31.38.0/26	10.31.38.1 – 10.31.38.62	10.31.38.63
26	10.31.38.64/26	10.31.38.65 – 10.31.38.126	10.31.38.127
27	10.31.38.128/26	10.31.38.129 – 10.31.38.190	10.31.38.191
28	10.31.38.192/26	10.31.38.193 – 10.31.38.254	10.31.38.255
29	10.31.39.0/26	10.31.39.1 – 10.31.39.62	10.31.39.63
30	10.31.39.64/26	10.31.39.65 – 10.31.39.126	10.31.39.127
31	10.31.39.128/26	10.31.39.129 – 10.31.39.190	10.31.39.191
32	10.31.39.192/26	10.31.39.193 – 10.31.39.254	10.31.39.255
33	10.31.40.0/26	10.31.40.1 – 10.31.40.62	10.31.40.63
34	10.31.40.64/26	10.31.40.65 – 10.31.40.126	10.31.40.127
35	10.31.40.128/26	10.31.40.129 – 10.31.40.190	10.31.40.191
36	10.31.40.192/26	10.31.40.193 – 10.31.40.254	10.31.40.255
37	10.31.41.0/26	10.31.41.1 – 10.31.41.62	10.31.41.63
38	10.31.41.64/26	10.31.41.65 – 10.31.41.126	10.31.41.127
39	10.31.41.128/26	10.31.41.129 – 10.31.41.190	10.31.41.191
40	10.31.41.192/26	10.31.41.193 – 10.31.41.254	10.31.41.255
41	10.31.42.0/26	10.31.42.1 – 10.31.42.62	10.31.42.63
42	10.31.42.64/26	10.31.42.65 – 10.31.42.126	10.31.42.127
43	10.31.42.128/26	10.31.42.129 – 10.31.42.190	10.31.42.191
44	10.31.42.192/26	10.31.42.193 – 10.31.42.254	10.31.42.255
45	10.31.43.0/26	10.31.43.1 – 10.31.43.62	10.31.43.63
46	10.31.43.64/26	10.31.43.65 – 10.31.43.126	10.31.43.127
47	10.31.43.128/26	10.31.43.129 – 10.31.43.190	10.31.43.191
48	10.31.43.192/26	10.31.43.193 – 10.31.43.254	10.31.43.255
49	10.31.44.0/26	10.31.44.1 – 10.31.44.62	10.31.44.63
50	10.31.44.64/26	10.31.44.65 – 10.31.44.126	10.31.44.127
51	10.31.44.128/26	10.31.44.129 – 10.31.44.190	10.31.44.191
52	10.31.44.192/26	10.31.44.193 – 10.31.44.254	10.31.44.255
53	10.31.45.0/26	10.31.45.1 – 10.31.45.62	10.31.45.63
54	10.31.45.64/26	10.31.45.65 – 10.31.45.126	10.31.45.127
55	10.31.45.128/26	10.31.45.129 – 10.31.45.190	10.31.45.191
56	10.31.45.192/26	10.31.45.193 – 10.31.45.254	10.31.45.255
57	10.31.46.0/26	10.31.46.1 – 10.31.46.62	10.31.46.63
58	10.31.46.64/26	10.31.46.65 – 10.31.46.126	10.31.46.127
59	10.31.46.128/26	10.31.46.129 – 10.31.46.190	10.31.46.191
60	10.31.46.192/26	10.31.46.193 – 10.31.46.254	10.31.46.255
61	10.31.47.0/26	10.31.47.1 – 10.31.47.62	10.31.47.63
62	10.31.47.64/26	10.31.47.65 – 10.31.47.126	10.31.47.127
63	10.31.47.128/26	10.31.47.129 – 10.31.47.190	10.31.47.191
64	10.31.47.192/26	10.31.47.193 – 10.31.47.254	10.31.47.255
65	10.31.48.0/26	10.31.48.1 – 10.31.48.62	10.31.48.63
66	10.31.48.64/26	10.31.48.65 – 10.31.48.126	10.31.48.127
67	10.31.48.128/26	10.31.48.129 – 10.31.48.190	10.31.48.191
68	10.31.48.192/26	10.31.48.193 – 10.31.48.254	10.31.48.255
69	10.31.49.0/26	10.31.49.1 – 10.31.49.62	10.31.49.63
70	10.31.49.64/26	10.31.49.65 – 10.31.49.126	10.31.49.127
71	10.31.49.128/26	10.31.49.129 – 10.31.49.190	10.31.49.191
72	10.31.49.192/26	10.31.49.193 – 10.31.49.254	10.31.49.255
73	10.31.50.0/26	10.31.50.1 – 10.31.50.62	10.31.50.63
74	10.31.50.64/26	10.31.50.65 – 10.31.50.126	10.31.50.127
75	10.31.50.128/26	10.31.50.129 – 10.31.50.190	10.31.50.191
76	10.31.50.192/26	10.31.50.193 – 10.31.50.254	10.31.50.255
77	10.31.51.0/26	10.31.51.1 – 10.31.51.62	10.31.51.63
78	10.31.51.64/26	10.31.51.65 – 10.31.51.126	10.31.51.127
79	10.31.51.128/26	10.31.51.129 – 10.31.51.190	10.31.51.191
80	10.31.51.192/26	10.31.51.193 – 10.31.51.254	10.31.51.255
81	10.31.52.0/26	10.31.52.1 – 10.31.52.62	10.31.52.63
82	10.31.52.64/26	10.31.52.65 – 10.31.52.126	10.31.52.127
83	10.31.52.128/26	10.31.52.129 – 10.31.52.190	10.31.52.191
84	10.31.52.192/26	10.31.52.193 – 10.31.52.254	10.31.52.255
85	10.31.53.0/26	10.31.53.1 – 10.31.53.62	10.31.53.63
86	10.31.53.64/26	10.31.53.65 – 10.31.53.126	10.31.53.127
87	10.31.53.128/26	10.31.53.129 – 10.31.53.190	10.31.53.191
88	10.31.53.192/26	10.31.53.193 – 10.31.53.254	10.31.53.255
89	10.31.54.0/26	10.31.54.1 – 10.31.54.62	10.31.54.63
90	10.31.54.64/26	10.31.54.65 – 10.31.54.126	10.31.54.127
91	10.31.54.128/26	10.31.54.129 – 10.31.54.190	10.31.54.191
92	10.31.54.192/26	10.31.54.193 – 10.31.54.254	10.31.54.255
93	10.31.55.0/26	10.31.55.1 – 10.31.55.62	10.31.55.63
94	10.31.55.64/26	10.31.55.65 – 10.31.55.126	10.31.55.127
95	10.31.55.128/26	10.31.55.129 – 10.31.55.190	10.31.55.191
96	10.31.55.192/26	10.31.55.193 – 10.31.55.254	10.31.55.255
97	10.31.56.0/26	10.31.56.1 – 10.31.56.62	10.31.56.63
98	10.31.56.64/26	10.31.56.65 – 10.31.56.126	10.31.56.127
99	10.31.56.128/26	10.31.56.129 – 10.31.56.190	10.31.56.191
100	10.31.56.192/26	10.31.56.193 – 10.31.56.254	10.31.56.255
101	10.31.57.0/26	10.31.57.1 – 10.31.57.62	10.31.57.63
102	10.31.57.64/26	10.31.57.65 – 10.31.57.126	10.31.57.127
103	10.31.57.128/26	10.31.57.129 – 10.31.57.190	10.31.57.191
104	10.31.57.192/26	10.31.57.193 – 10.31.57.254	10.31.57.255
105	10.31.58.0/26	10.31.58.1 – 10.31.58.62	10.31.58.63
106	10.31.58.64/26	10.31.58.65 – 10.31.58.126	10.31.58.127
107	10.31.58.128/26	10.31.58.129 – 10.31.58.190	10.31.58.191
108	10.31.58.192/26	10.31.58.193 – 10.31.58.254	10.31.58.255
109	10.31.59.0/26	10.31.59.1 – 10.31.59.62	10.31.59.63
110	10.31.59.64/26	10.31.59.65 – 10.31.59.126	10.31.59.127
111	10.31.59.128/26	10.31.59.129 – 10.31.59.190	10.31.59.191
112	10.31.59.192/26	10.31.59.193 – 10.31.59.254	10.31.59.255
113	10.31.60.0/26	10.31.60.1 – 10.31.60.62	10.31.60.63
114	10.31.60.64/26	10.31.60.65 – 10.31.60.126	10.31.60.127
115	10.31.60.128/26	10.31.60.129 – 10.31.60.190	10.31.60.191
116	10.31.60.192/26	10.31.60.193 – 10.31.60.254	10.31.60.255
117	10.31.61.0/26	10.31.61.1 – 10.31.61.62	10.31.61.63
118	10.31.61.64/26	10.31.61.65 – 10.31.61.126	10.31.61.127
119	10.31.61.128/26	10.31.61.129 – 10.31.61.190	10.31.61.191
120	10.31.61.192/26	10.31.61.193 – 10.31.61.254	10.31.61.255
121	10.31.62.0/26	10.31.62.1 – 10.31.62.62	10.31.62.63
122	10.31.62.64/26	10.31.62.65 – 10.31.62.126	10.31.62.127
123	10.31.62.128/26	10.31.62.129 – 10.31.62.190	10.31.62.191
124	10.31.62.192/26	10.31.62.193 – 10.31.62.254	10.31.62.255
125	10.31.63.0/26	10.31.63.1 – 10.31.63.62	10.31.63.63
126	10.31.63.64/26	10.31.63.65 – 10.31.63.126	10.31.63.127
127	10.31.63.128/26	10.31.63.129 – 10.31.63.190	10.31.63.191
128	10.31.63.192/26	10.31.63.193 – 10.31.63.254	10.31.63.255

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