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)10.3.253.0/25

network10.3.253.0/25

broadcast10.3.253.127

first host10.3.253.1

last host10.3.253.126

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.3.253.0/25

address00001010.00000011.11111101.00000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000011.11111101.00000000

broadcast00001010.00000011.11111101.01111111

green = network part, grey = host part

hex0x0a03fd00

decimal168033536

reverse dns0.253.3.10.in-addr.arpa

ipv4-mapped::ffff:a03:fd00

/25 split into /31 · 64 subnets

close ×

#	network	host range	broadcast
1	10.3.253.0/31	10.3.253.0 – 10.3.253.1	10.3.253.1
2	10.3.253.2/31	10.3.253.2 – 10.3.253.3	10.3.253.3
3	10.3.253.4/31	10.3.253.4 – 10.3.253.5	10.3.253.5
4	10.3.253.6/31	10.3.253.6 – 10.3.253.7	10.3.253.7
5	10.3.253.8/31	10.3.253.8 – 10.3.253.9	10.3.253.9
6	10.3.253.10/31	10.3.253.10 – 10.3.253.11	10.3.253.11
7	10.3.253.12/31	10.3.253.12 – 10.3.253.13	10.3.253.13
8	10.3.253.14/31	10.3.253.14 – 10.3.253.15	10.3.253.15
9	10.3.253.16/31	10.3.253.16 – 10.3.253.17	10.3.253.17
10	10.3.253.18/31	10.3.253.18 – 10.3.253.19	10.3.253.19
11	10.3.253.20/31	10.3.253.20 – 10.3.253.21	10.3.253.21
12	10.3.253.22/31	10.3.253.22 – 10.3.253.23	10.3.253.23
13	10.3.253.24/31	10.3.253.24 – 10.3.253.25	10.3.253.25
14	10.3.253.26/31	10.3.253.26 – 10.3.253.27	10.3.253.27
15	10.3.253.28/31	10.3.253.28 – 10.3.253.29	10.3.253.29
16	10.3.253.30/31	10.3.253.30 – 10.3.253.31	10.3.253.31
17	10.3.253.32/31	10.3.253.32 – 10.3.253.33	10.3.253.33
18	10.3.253.34/31	10.3.253.34 – 10.3.253.35	10.3.253.35
19	10.3.253.36/31	10.3.253.36 – 10.3.253.37	10.3.253.37
20	10.3.253.38/31	10.3.253.38 – 10.3.253.39	10.3.253.39
21	10.3.253.40/31	10.3.253.40 – 10.3.253.41	10.3.253.41
22	10.3.253.42/31	10.3.253.42 – 10.3.253.43	10.3.253.43
23	10.3.253.44/31	10.3.253.44 – 10.3.253.45	10.3.253.45
24	10.3.253.46/31	10.3.253.46 – 10.3.253.47	10.3.253.47
25	10.3.253.48/31	10.3.253.48 – 10.3.253.49	10.3.253.49
26	10.3.253.50/31	10.3.253.50 – 10.3.253.51	10.3.253.51
27	10.3.253.52/31	10.3.253.52 – 10.3.253.53	10.3.253.53
28	10.3.253.54/31	10.3.253.54 – 10.3.253.55	10.3.253.55
29	10.3.253.56/31	10.3.253.56 – 10.3.253.57	10.3.253.57
30	10.3.253.58/31	10.3.253.58 – 10.3.253.59	10.3.253.59
31	10.3.253.60/31	10.3.253.60 – 10.3.253.61	10.3.253.61
32	10.3.253.62/31	10.3.253.62 – 10.3.253.63	10.3.253.63
33	10.3.253.64/31	10.3.253.64 – 10.3.253.65	10.3.253.65
34	10.3.253.66/31	10.3.253.66 – 10.3.253.67	10.3.253.67
35	10.3.253.68/31	10.3.253.68 – 10.3.253.69	10.3.253.69
36	10.3.253.70/31	10.3.253.70 – 10.3.253.71	10.3.253.71
37	10.3.253.72/31	10.3.253.72 – 10.3.253.73	10.3.253.73
38	10.3.253.74/31	10.3.253.74 – 10.3.253.75	10.3.253.75
39	10.3.253.76/31	10.3.253.76 – 10.3.253.77	10.3.253.77
40	10.3.253.78/31	10.3.253.78 – 10.3.253.79	10.3.253.79
41	10.3.253.80/31	10.3.253.80 – 10.3.253.81	10.3.253.81
42	10.3.253.82/31	10.3.253.82 – 10.3.253.83	10.3.253.83
43	10.3.253.84/31	10.3.253.84 – 10.3.253.85	10.3.253.85
44	10.3.253.86/31	10.3.253.86 – 10.3.253.87	10.3.253.87
45	10.3.253.88/31	10.3.253.88 – 10.3.253.89	10.3.253.89
46	10.3.253.90/31	10.3.253.90 – 10.3.253.91	10.3.253.91
47	10.3.253.92/31	10.3.253.92 – 10.3.253.93	10.3.253.93
48	10.3.253.94/31	10.3.253.94 – 10.3.253.95	10.3.253.95
49	10.3.253.96/31	10.3.253.96 – 10.3.253.97	10.3.253.97
50	10.3.253.98/31	10.3.253.98 – 10.3.253.99	10.3.253.99
51	10.3.253.100/31	10.3.253.100 – 10.3.253.101	10.3.253.101
52	10.3.253.102/31	10.3.253.102 – 10.3.253.103	10.3.253.103
53	10.3.253.104/31	10.3.253.104 – 10.3.253.105	10.3.253.105
54	10.3.253.106/31	10.3.253.106 – 10.3.253.107	10.3.253.107
55	10.3.253.108/31	10.3.253.108 – 10.3.253.109	10.3.253.109
56	10.3.253.110/31	10.3.253.110 – 10.3.253.111	10.3.253.111
57	10.3.253.112/31	10.3.253.112 – 10.3.253.113	10.3.253.113
58	10.3.253.114/31	10.3.253.114 – 10.3.253.115	10.3.253.115
59	10.3.253.116/31	10.3.253.116 – 10.3.253.117	10.3.253.117
60	10.3.253.118/31	10.3.253.118 – 10.3.253.119	10.3.253.119
61	10.3.253.120/31	10.3.253.120 – 10.3.253.121	10.3.253.121
62	10.3.253.122/31	10.3.253.122 – 10.3.253.123	10.3.253.123
63	10.3.253.124/31	10.3.253.124 – 10.3.253.125	10.3.253.125
64	10.3.253.126/31	10.3.253.126 – 10.3.253.127	10.3.253.127

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