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)10.151.45.0/25

network10.151.45.0/25

broadcast10.151.45.127

first host10.151.45.1

last host10.151.45.126

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.151.45.0/25

address00001010.10010111.00101101.00000000

subnet mask11111111.11111111.11111111.10000000

network00001010.10010111.00101101.00000000

broadcast00001010.10010111.00101101.01111111

green = network part, grey = host part

hex0x0a972d00

decimal177679616

reverse dns0.45.151.10.in-addr.arpa

ipv4-mapped::ffff:a97:2d00

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.151.45.0/32	10.151.45.0 – 10.151.45.0	10.151.45.0
2	10.151.45.1/32	10.151.45.1 – 10.151.45.1	10.151.45.1
3	10.151.45.2/32	10.151.45.2 – 10.151.45.2	10.151.45.2
4	10.151.45.3/32	10.151.45.3 – 10.151.45.3	10.151.45.3
5	10.151.45.4/32	10.151.45.4 – 10.151.45.4	10.151.45.4
6	10.151.45.5/32	10.151.45.5 – 10.151.45.5	10.151.45.5
7	10.151.45.6/32	10.151.45.6 – 10.151.45.6	10.151.45.6
8	10.151.45.7/32	10.151.45.7 – 10.151.45.7	10.151.45.7
9	10.151.45.8/32	10.151.45.8 – 10.151.45.8	10.151.45.8
10	10.151.45.9/32	10.151.45.9 – 10.151.45.9	10.151.45.9
11	10.151.45.10/32	10.151.45.10 – 10.151.45.10	10.151.45.10
12	10.151.45.11/32	10.151.45.11 – 10.151.45.11	10.151.45.11
13	10.151.45.12/32	10.151.45.12 – 10.151.45.12	10.151.45.12
14	10.151.45.13/32	10.151.45.13 – 10.151.45.13	10.151.45.13
15	10.151.45.14/32	10.151.45.14 – 10.151.45.14	10.151.45.14
16	10.151.45.15/32	10.151.45.15 – 10.151.45.15	10.151.45.15
17	10.151.45.16/32	10.151.45.16 – 10.151.45.16	10.151.45.16
18	10.151.45.17/32	10.151.45.17 – 10.151.45.17	10.151.45.17
19	10.151.45.18/32	10.151.45.18 – 10.151.45.18	10.151.45.18
20	10.151.45.19/32	10.151.45.19 – 10.151.45.19	10.151.45.19
21	10.151.45.20/32	10.151.45.20 – 10.151.45.20	10.151.45.20
22	10.151.45.21/32	10.151.45.21 – 10.151.45.21	10.151.45.21
23	10.151.45.22/32	10.151.45.22 – 10.151.45.22	10.151.45.22
24	10.151.45.23/32	10.151.45.23 – 10.151.45.23	10.151.45.23
25	10.151.45.24/32	10.151.45.24 – 10.151.45.24	10.151.45.24
26	10.151.45.25/32	10.151.45.25 – 10.151.45.25	10.151.45.25
27	10.151.45.26/32	10.151.45.26 – 10.151.45.26	10.151.45.26
28	10.151.45.27/32	10.151.45.27 – 10.151.45.27	10.151.45.27
29	10.151.45.28/32	10.151.45.28 – 10.151.45.28	10.151.45.28
30	10.151.45.29/32	10.151.45.29 – 10.151.45.29	10.151.45.29
31	10.151.45.30/32	10.151.45.30 – 10.151.45.30	10.151.45.30
32	10.151.45.31/32	10.151.45.31 – 10.151.45.31	10.151.45.31
33	10.151.45.32/32	10.151.45.32 – 10.151.45.32	10.151.45.32
34	10.151.45.33/32	10.151.45.33 – 10.151.45.33	10.151.45.33
35	10.151.45.34/32	10.151.45.34 – 10.151.45.34	10.151.45.34
36	10.151.45.35/32	10.151.45.35 – 10.151.45.35	10.151.45.35
37	10.151.45.36/32	10.151.45.36 – 10.151.45.36	10.151.45.36
38	10.151.45.37/32	10.151.45.37 – 10.151.45.37	10.151.45.37
39	10.151.45.38/32	10.151.45.38 – 10.151.45.38	10.151.45.38
40	10.151.45.39/32	10.151.45.39 – 10.151.45.39	10.151.45.39
41	10.151.45.40/32	10.151.45.40 – 10.151.45.40	10.151.45.40
42	10.151.45.41/32	10.151.45.41 – 10.151.45.41	10.151.45.41
43	10.151.45.42/32	10.151.45.42 – 10.151.45.42	10.151.45.42
44	10.151.45.43/32	10.151.45.43 – 10.151.45.43	10.151.45.43
45	10.151.45.44/32	10.151.45.44 – 10.151.45.44	10.151.45.44
46	10.151.45.45/32	10.151.45.45 – 10.151.45.45	10.151.45.45
47	10.151.45.46/32	10.151.45.46 – 10.151.45.46	10.151.45.46
48	10.151.45.47/32	10.151.45.47 – 10.151.45.47	10.151.45.47
49	10.151.45.48/32	10.151.45.48 – 10.151.45.48	10.151.45.48
50	10.151.45.49/32	10.151.45.49 – 10.151.45.49	10.151.45.49
51	10.151.45.50/32	10.151.45.50 – 10.151.45.50	10.151.45.50
52	10.151.45.51/32	10.151.45.51 – 10.151.45.51	10.151.45.51
53	10.151.45.52/32	10.151.45.52 – 10.151.45.52	10.151.45.52
54	10.151.45.53/32	10.151.45.53 – 10.151.45.53	10.151.45.53
55	10.151.45.54/32	10.151.45.54 – 10.151.45.54	10.151.45.54
56	10.151.45.55/32	10.151.45.55 – 10.151.45.55	10.151.45.55
57	10.151.45.56/32	10.151.45.56 – 10.151.45.56	10.151.45.56
58	10.151.45.57/32	10.151.45.57 – 10.151.45.57	10.151.45.57
59	10.151.45.58/32	10.151.45.58 – 10.151.45.58	10.151.45.58
60	10.151.45.59/32	10.151.45.59 – 10.151.45.59	10.151.45.59
61	10.151.45.60/32	10.151.45.60 – 10.151.45.60	10.151.45.60
62	10.151.45.61/32	10.151.45.61 – 10.151.45.61	10.151.45.61
63	10.151.45.62/32	10.151.45.62 – 10.151.45.62	10.151.45.62
64	10.151.45.63/32	10.151.45.63 – 10.151.45.63	10.151.45.63
65	10.151.45.64/32	10.151.45.64 – 10.151.45.64	10.151.45.64
66	10.151.45.65/32	10.151.45.65 – 10.151.45.65	10.151.45.65
67	10.151.45.66/32	10.151.45.66 – 10.151.45.66	10.151.45.66
68	10.151.45.67/32	10.151.45.67 – 10.151.45.67	10.151.45.67
69	10.151.45.68/32	10.151.45.68 – 10.151.45.68	10.151.45.68
70	10.151.45.69/32	10.151.45.69 – 10.151.45.69	10.151.45.69
71	10.151.45.70/32	10.151.45.70 – 10.151.45.70	10.151.45.70
72	10.151.45.71/32	10.151.45.71 – 10.151.45.71	10.151.45.71
73	10.151.45.72/32	10.151.45.72 – 10.151.45.72	10.151.45.72
74	10.151.45.73/32	10.151.45.73 – 10.151.45.73	10.151.45.73
75	10.151.45.74/32	10.151.45.74 – 10.151.45.74	10.151.45.74
76	10.151.45.75/32	10.151.45.75 – 10.151.45.75	10.151.45.75
77	10.151.45.76/32	10.151.45.76 – 10.151.45.76	10.151.45.76
78	10.151.45.77/32	10.151.45.77 – 10.151.45.77	10.151.45.77
79	10.151.45.78/32	10.151.45.78 – 10.151.45.78	10.151.45.78
80	10.151.45.79/32	10.151.45.79 – 10.151.45.79	10.151.45.79
81	10.151.45.80/32	10.151.45.80 – 10.151.45.80	10.151.45.80
82	10.151.45.81/32	10.151.45.81 – 10.151.45.81	10.151.45.81
83	10.151.45.82/32	10.151.45.82 – 10.151.45.82	10.151.45.82
84	10.151.45.83/32	10.151.45.83 – 10.151.45.83	10.151.45.83
85	10.151.45.84/32	10.151.45.84 – 10.151.45.84	10.151.45.84
86	10.151.45.85/32	10.151.45.85 – 10.151.45.85	10.151.45.85
87	10.151.45.86/32	10.151.45.86 – 10.151.45.86	10.151.45.86
88	10.151.45.87/32	10.151.45.87 – 10.151.45.87	10.151.45.87
89	10.151.45.88/32	10.151.45.88 – 10.151.45.88	10.151.45.88
90	10.151.45.89/32	10.151.45.89 – 10.151.45.89	10.151.45.89
91	10.151.45.90/32	10.151.45.90 – 10.151.45.90	10.151.45.90
92	10.151.45.91/32	10.151.45.91 – 10.151.45.91	10.151.45.91
93	10.151.45.92/32	10.151.45.92 – 10.151.45.92	10.151.45.92
94	10.151.45.93/32	10.151.45.93 – 10.151.45.93	10.151.45.93
95	10.151.45.94/32	10.151.45.94 – 10.151.45.94	10.151.45.94
96	10.151.45.95/32	10.151.45.95 – 10.151.45.95	10.151.45.95
97	10.151.45.96/32	10.151.45.96 – 10.151.45.96	10.151.45.96
98	10.151.45.97/32	10.151.45.97 – 10.151.45.97	10.151.45.97
99	10.151.45.98/32	10.151.45.98 – 10.151.45.98	10.151.45.98
100	10.151.45.99/32	10.151.45.99 – 10.151.45.99	10.151.45.99
101	10.151.45.100/32	10.151.45.100 – 10.151.45.100	10.151.45.100
102	10.151.45.101/32	10.151.45.101 – 10.151.45.101	10.151.45.101
103	10.151.45.102/32	10.151.45.102 – 10.151.45.102	10.151.45.102
104	10.151.45.103/32	10.151.45.103 – 10.151.45.103	10.151.45.103
105	10.151.45.104/32	10.151.45.104 – 10.151.45.104	10.151.45.104
106	10.151.45.105/32	10.151.45.105 – 10.151.45.105	10.151.45.105
107	10.151.45.106/32	10.151.45.106 – 10.151.45.106	10.151.45.106
108	10.151.45.107/32	10.151.45.107 – 10.151.45.107	10.151.45.107
109	10.151.45.108/32	10.151.45.108 – 10.151.45.108	10.151.45.108
110	10.151.45.109/32	10.151.45.109 – 10.151.45.109	10.151.45.109
111	10.151.45.110/32	10.151.45.110 – 10.151.45.110	10.151.45.110
112	10.151.45.111/32	10.151.45.111 – 10.151.45.111	10.151.45.111
113	10.151.45.112/32	10.151.45.112 – 10.151.45.112	10.151.45.112
114	10.151.45.113/32	10.151.45.113 – 10.151.45.113	10.151.45.113
115	10.151.45.114/32	10.151.45.114 – 10.151.45.114	10.151.45.114
116	10.151.45.115/32	10.151.45.115 – 10.151.45.115	10.151.45.115
117	10.151.45.116/32	10.151.45.116 – 10.151.45.116	10.151.45.116
118	10.151.45.117/32	10.151.45.117 – 10.151.45.117	10.151.45.117
119	10.151.45.118/32	10.151.45.118 – 10.151.45.118	10.151.45.118
120	10.151.45.119/32	10.151.45.119 – 10.151.45.119	10.151.45.119
121	10.151.45.120/32	10.151.45.120 – 10.151.45.120	10.151.45.120
122	10.151.45.121/32	10.151.45.121 – 10.151.45.121	10.151.45.121
123	10.151.45.122/32	10.151.45.122 – 10.151.45.122	10.151.45.122
124	10.151.45.123/32	10.151.45.123 – 10.151.45.123	10.151.45.123
125	10.151.45.124/32	10.151.45.124 – 10.151.45.124	10.151.45.124
126	10.151.45.125/32	10.151.45.125 – 10.151.45.125	10.151.45.125
127	10.151.45.126/32	10.151.45.126 – 10.151.45.126	10.151.45.126
128	10.151.45.127/32	10.151.45.127 – 10.151.45.127	10.151.45.127

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 →