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)10.2.133.0/25

network10.2.133.0/25

broadcast10.2.133.127

first host10.2.133.1

last host10.2.133.126

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.2.133.0/25

address00001010.00000010.10000101.00000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000010.10000101.00000000

broadcast00001010.00000010.10000101.01111111

green = network part, grey = host part

hex0x0a028500

decimal167937280

reverse dns0.133.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:8500

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.133.0/32	10.2.133.0 – 10.2.133.0	10.2.133.0
2	10.2.133.1/32	10.2.133.1 – 10.2.133.1	10.2.133.1
3	10.2.133.2/32	10.2.133.2 – 10.2.133.2	10.2.133.2
4	10.2.133.3/32	10.2.133.3 – 10.2.133.3	10.2.133.3
5	10.2.133.4/32	10.2.133.4 – 10.2.133.4	10.2.133.4
6	10.2.133.5/32	10.2.133.5 – 10.2.133.5	10.2.133.5
7	10.2.133.6/32	10.2.133.6 – 10.2.133.6	10.2.133.6
8	10.2.133.7/32	10.2.133.7 – 10.2.133.7	10.2.133.7
9	10.2.133.8/32	10.2.133.8 – 10.2.133.8	10.2.133.8
10	10.2.133.9/32	10.2.133.9 – 10.2.133.9	10.2.133.9
11	10.2.133.10/32	10.2.133.10 – 10.2.133.10	10.2.133.10
12	10.2.133.11/32	10.2.133.11 – 10.2.133.11	10.2.133.11
13	10.2.133.12/32	10.2.133.12 – 10.2.133.12	10.2.133.12
14	10.2.133.13/32	10.2.133.13 – 10.2.133.13	10.2.133.13
15	10.2.133.14/32	10.2.133.14 – 10.2.133.14	10.2.133.14
16	10.2.133.15/32	10.2.133.15 – 10.2.133.15	10.2.133.15
17	10.2.133.16/32	10.2.133.16 – 10.2.133.16	10.2.133.16
18	10.2.133.17/32	10.2.133.17 – 10.2.133.17	10.2.133.17
19	10.2.133.18/32	10.2.133.18 – 10.2.133.18	10.2.133.18
20	10.2.133.19/32	10.2.133.19 – 10.2.133.19	10.2.133.19
21	10.2.133.20/32	10.2.133.20 – 10.2.133.20	10.2.133.20
22	10.2.133.21/32	10.2.133.21 – 10.2.133.21	10.2.133.21
23	10.2.133.22/32	10.2.133.22 – 10.2.133.22	10.2.133.22
24	10.2.133.23/32	10.2.133.23 – 10.2.133.23	10.2.133.23
25	10.2.133.24/32	10.2.133.24 – 10.2.133.24	10.2.133.24
26	10.2.133.25/32	10.2.133.25 – 10.2.133.25	10.2.133.25
27	10.2.133.26/32	10.2.133.26 – 10.2.133.26	10.2.133.26
28	10.2.133.27/32	10.2.133.27 – 10.2.133.27	10.2.133.27
29	10.2.133.28/32	10.2.133.28 – 10.2.133.28	10.2.133.28
30	10.2.133.29/32	10.2.133.29 – 10.2.133.29	10.2.133.29
31	10.2.133.30/32	10.2.133.30 – 10.2.133.30	10.2.133.30
32	10.2.133.31/32	10.2.133.31 – 10.2.133.31	10.2.133.31
33	10.2.133.32/32	10.2.133.32 – 10.2.133.32	10.2.133.32
34	10.2.133.33/32	10.2.133.33 – 10.2.133.33	10.2.133.33
35	10.2.133.34/32	10.2.133.34 – 10.2.133.34	10.2.133.34
36	10.2.133.35/32	10.2.133.35 – 10.2.133.35	10.2.133.35
37	10.2.133.36/32	10.2.133.36 – 10.2.133.36	10.2.133.36
38	10.2.133.37/32	10.2.133.37 – 10.2.133.37	10.2.133.37
39	10.2.133.38/32	10.2.133.38 – 10.2.133.38	10.2.133.38
40	10.2.133.39/32	10.2.133.39 – 10.2.133.39	10.2.133.39
41	10.2.133.40/32	10.2.133.40 – 10.2.133.40	10.2.133.40
42	10.2.133.41/32	10.2.133.41 – 10.2.133.41	10.2.133.41
43	10.2.133.42/32	10.2.133.42 – 10.2.133.42	10.2.133.42
44	10.2.133.43/32	10.2.133.43 – 10.2.133.43	10.2.133.43
45	10.2.133.44/32	10.2.133.44 – 10.2.133.44	10.2.133.44
46	10.2.133.45/32	10.2.133.45 – 10.2.133.45	10.2.133.45
47	10.2.133.46/32	10.2.133.46 – 10.2.133.46	10.2.133.46
48	10.2.133.47/32	10.2.133.47 – 10.2.133.47	10.2.133.47
49	10.2.133.48/32	10.2.133.48 – 10.2.133.48	10.2.133.48
50	10.2.133.49/32	10.2.133.49 – 10.2.133.49	10.2.133.49
51	10.2.133.50/32	10.2.133.50 – 10.2.133.50	10.2.133.50
52	10.2.133.51/32	10.2.133.51 – 10.2.133.51	10.2.133.51
53	10.2.133.52/32	10.2.133.52 – 10.2.133.52	10.2.133.52
54	10.2.133.53/32	10.2.133.53 – 10.2.133.53	10.2.133.53
55	10.2.133.54/32	10.2.133.54 – 10.2.133.54	10.2.133.54
56	10.2.133.55/32	10.2.133.55 – 10.2.133.55	10.2.133.55
57	10.2.133.56/32	10.2.133.56 – 10.2.133.56	10.2.133.56
58	10.2.133.57/32	10.2.133.57 – 10.2.133.57	10.2.133.57
59	10.2.133.58/32	10.2.133.58 – 10.2.133.58	10.2.133.58
60	10.2.133.59/32	10.2.133.59 – 10.2.133.59	10.2.133.59
61	10.2.133.60/32	10.2.133.60 – 10.2.133.60	10.2.133.60
62	10.2.133.61/32	10.2.133.61 – 10.2.133.61	10.2.133.61
63	10.2.133.62/32	10.2.133.62 – 10.2.133.62	10.2.133.62
64	10.2.133.63/32	10.2.133.63 – 10.2.133.63	10.2.133.63
65	10.2.133.64/32	10.2.133.64 – 10.2.133.64	10.2.133.64
66	10.2.133.65/32	10.2.133.65 – 10.2.133.65	10.2.133.65
67	10.2.133.66/32	10.2.133.66 – 10.2.133.66	10.2.133.66
68	10.2.133.67/32	10.2.133.67 – 10.2.133.67	10.2.133.67
69	10.2.133.68/32	10.2.133.68 – 10.2.133.68	10.2.133.68
70	10.2.133.69/32	10.2.133.69 – 10.2.133.69	10.2.133.69
71	10.2.133.70/32	10.2.133.70 – 10.2.133.70	10.2.133.70
72	10.2.133.71/32	10.2.133.71 – 10.2.133.71	10.2.133.71
73	10.2.133.72/32	10.2.133.72 – 10.2.133.72	10.2.133.72
74	10.2.133.73/32	10.2.133.73 – 10.2.133.73	10.2.133.73
75	10.2.133.74/32	10.2.133.74 – 10.2.133.74	10.2.133.74
76	10.2.133.75/32	10.2.133.75 – 10.2.133.75	10.2.133.75
77	10.2.133.76/32	10.2.133.76 – 10.2.133.76	10.2.133.76
78	10.2.133.77/32	10.2.133.77 – 10.2.133.77	10.2.133.77
79	10.2.133.78/32	10.2.133.78 – 10.2.133.78	10.2.133.78
80	10.2.133.79/32	10.2.133.79 – 10.2.133.79	10.2.133.79
81	10.2.133.80/32	10.2.133.80 – 10.2.133.80	10.2.133.80
82	10.2.133.81/32	10.2.133.81 – 10.2.133.81	10.2.133.81
83	10.2.133.82/32	10.2.133.82 – 10.2.133.82	10.2.133.82
84	10.2.133.83/32	10.2.133.83 – 10.2.133.83	10.2.133.83
85	10.2.133.84/32	10.2.133.84 – 10.2.133.84	10.2.133.84
86	10.2.133.85/32	10.2.133.85 – 10.2.133.85	10.2.133.85
87	10.2.133.86/32	10.2.133.86 – 10.2.133.86	10.2.133.86
88	10.2.133.87/32	10.2.133.87 – 10.2.133.87	10.2.133.87
89	10.2.133.88/32	10.2.133.88 – 10.2.133.88	10.2.133.88
90	10.2.133.89/32	10.2.133.89 – 10.2.133.89	10.2.133.89
91	10.2.133.90/32	10.2.133.90 – 10.2.133.90	10.2.133.90
92	10.2.133.91/32	10.2.133.91 – 10.2.133.91	10.2.133.91
93	10.2.133.92/32	10.2.133.92 – 10.2.133.92	10.2.133.92
94	10.2.133.93/32	10.2.133.93 – 10.2.133.93	10.2.133.93
95	10.2.133.94/32	10.2.133.94 – 10.2.133.94	10.2.133.94
96	10.2.133.95/32	10.2.133.95 – 10.2.133.95	10.2.133.95
97	10.2.133.96/32	10.2.133.96 – 10.2.133.96	10.2.133.96
98	10.2.133.97/32	10.2.133.97 – 10.2.133.97	10.2.133.97
99	10.2.133.98/32	10.2.133.98 – 10.2.133.98	10.2.133.98
100	10.2.133.99/32	10.2.133.99 – 10.2.133.99	10.2.133.99
101	10.2.133.100/32	10.2.133.100 – 10.2.133.100	10.2.133.100
102	10.2.133.101/32	10.2.133.101 – 10.2.133.101	10.2.133.101
103	10.2.133.102/32	10.2.133.102 – 10.2.133.102	10.2.133.102
104	10.2.133.103/32	10.2.133.103 – 10.2.133.103	10.2.133.103
105	10.2.133.104/32	10.2.133.104 – 10.2.133.104	10.2.133.104
106	10.2.133.105/32	10.2.133.105 – 10.2.133.105	10.2.133.105
107	10.2.133.106/32	10.2.133.106 – 10.2.133.106	10.2.133.106
108	10.2.133.107/32	10.2.133.107 – 10.2.133.107	10.2.133.107
109	10.2.133.108/32	10.2.133.108 – 10.2.133.108	10.2.133.108
110	10.2.133.109/32	10.2.133.109 – 10.2.133.109	10.2.133.109
111	10.2.133.110/32	10.2.133.110 – 10.2.133.110	10.2.133.110
112	10.2.133.111/32	10.2.133.111 – 10.2.133.111	10.2.133.111
113	10.2.133.112/32	10.2.133.112 – 10.2.133.112	10.2.133.112
114	10.2.133.113/32	10.2.133.113 – 10.2.133.113	10.2.133.113
115	10.2.133.114/32	10.2.133.114 – 10.2.133.114	10.2.133.114
116	10.2.133.115/32	10.2.133.115 – 10.2.133.115	10.2.133.115
117	10.2.133.116/32	10.2.133.116 – 10.2.133.116	10.2.133.116
118	10.2.133.117/32	10.2.133.117 – 10.2.133.117	10.2.133.117
119	10.2.133.118/32	10.2.133.118 – 10.2.133.118	10.2.133.118
120	10.2.133.119/32	10.2.133.119 – 10.2.133.119	10.2.133.119
121	10.2.133.120/32	10.2.133.120 – 10.2.133.120	10.2.133.120
122	10.2.133.121/32	10.2.133.121 – 10.2.133.121	10.2.133.121
123	10.2.133.122/32	10.2.133.122 – 10.2.133.122	10.2.133.122
124	10.2.133.123/32	10.2.133.123 – 10.2.133.123	10.2.133.123
125	10.2.133.124/32	10.2.133.124 – 10.2.133.124	10.2.133.124
126	10.2.133.125/32	10.2.133.125 – 10.2.133.125	10.2.133.125
127	10.2.133.126/32	10.2.133.126 – 10.2.133.126	10.2.133.126
128	10.2.133.127/32	10.2.133.127 – 10.2.133.127	10.2.133.127

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 →