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)10.239.71.0/25

network10.239.71.0/25

broadcast10.239.71.127

first host10.239.71.1

last host10.239.71.126

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.239.71.0/25

address00001010.11101111.01000111.00000000

subnet mask11111111.11111111.11111111.10000000

network00001010.11101111.01000111.00000000

broadcast00001010.11101111.01000111.01111111

green = network part, grey = host part

hex0x0aef4700

decimal183453440

reverse dns0.71.239.10.in-addr.arpa

ipv4-mapped::ffff:aef:4700

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.239.71.0/32	10.239.71.0 – 10.239.71.0	10.239.71.0
2	10.239.71.1/32	10.239.71.1 – 10.239.71.1	10.239.71.1
3	10.239.71.2/32	10.239.71.2 – 10.239.71.2	10.239.71.2
4	10.239.71.3/32	10.239.71.3 – 10.239.71.3	10.239.71.3
5	10.239.71.4/32	10.239.71.4 – 10.239.71.4	10.239.71.4
6	10.239.71.5/32	10.239.71.5 – 10.239.71.5	10.239.71.5
7	10.239.71.6/32	10.239.71.6 – 10.239.71.6	10.239.71.6
8	10.239.71.7/32	10.239.71.7 – 10.239.71.7	10.239.71.7
9	10.239.71.8/32	10.239.71.8 – 10.239.71.8	10.239.71.8
10	10.239.71.9/32	10.239.71.9 – 10.239.71.9	10.239.71.9
11	10.239.71.10/32	10.239.71.10 – 10.239.71.10	10.239.71.10
12	10.239.71.11/32	10.239.71.11 – 10.239.71.11	10.239.71.11
13	10.239.71.12/32	10.239.71.12 – 10.239.71.12	10.239.71.12
14	10.239.71.13/32	10.239.71.13 – 10.239.71.13	10.239.71.13
15	10.239.71.14/32	10.239.71.14 – 10.239.71.14	10.239.71.14
16	10.239.71.15/32	10.239.71.15 – 10.239.71.15	10.239.71.15
17	10.239.71.16/32	10.239.71.16 – 10.239.71.16	10.239.71.16
18	10.239.71.17/32	10.239.71.17 – 10.239.71.17	10.239.71.17
19	10.239.71.18/32	10.239.71.18 – 10.239.71.18	10.239.71.18
20	10.239.71.19/32	10.239.71.19 – 10.239.71.19	10.239.71.19
21	10.239.71.20/32	10.239.71.20 – 10.239.71.20	10.239.71.20
22	10.239.71.21/32	10.239.71.21 – 10.239.71.21	10.239.71.21
23	10.239.71.22/32	10.239.71.22 – 10.239.71.22	10.239.71.22
24	10.239.71.23/32	10.239.71.23 – 10.239.71.23	10.239.71.23
25	10.239.71.24/32	10.239.71.24 – 10.239.71.24	10.239.71.24
26	10.239.71.25/32	10.239.71.25 – 10.239.71.25	10.239.71.25
27	10.239.71.26/32	10.239.71.26 – 10.239.71.26	10.239.71.26
28	10.239.71.27/32	10.239.71.27 – 10.239.71.27	10.239.71.27
29	10.239.71.28/32	10.239.71.28 – 10.239.71.28	10.239.71.28
30	10.239.71.29/32	10.239.71.29 – 10.239.71.29	10.239.71.29
31	10.239.71.30/32	10.239.71.30 – 10.239.71.30	10.239.71.30
32	10.239.71.31/32	10.239.71.31 – 10.239.71.31	10.239.71.31
33	10.239.71.32/32	10.239.71.32 – 10.239.71.32	10.239.71.32
34	10.239.71.33/32	10.239.71.33 – 10.239.71.33	10.239.71.33
35	10.239.71.34/32	10.239.71.34 – 10.239.71.34	10.239.71.34
36	10.239.71.35/32	10.239.71.35 – 10.239.71.35	10.239.71.35
37	10.239.71.36/32	10.239.71.36 – 10.239.71.36	10.239.71.36
38	10.239.71.37/32	10.239.71.37 – 10.239.71.37	10.239.71.37
39	10.239.71.38/32	10.239.71.38 – 10.239.71.38	10.239.71.38
40	10.239.71.39/32	10.239.71.39 – 10.239.71.39	10.239.71.39
41	10.239.71.40/32	10.239.71.40 – 10.239.71.40	10.239.71.40
42	10.239.71.41/32	10.239.71.41 – 10.239.71.41	10.239.71.41
43	10.239.71.42/32	10.239.71.42 – 10.239.71.42	10.239.71.42
44	10.239.71.43/32	10.239.71.43 – 10.239.71.43	10.239.71.43
45	10.239.71.44/32	10.239.71.44 – 10.239.71.44	10.239.71.44
46	10.239.71.45/32	10.239.71.45 – 10.239.71.45	10.239.71.45
47	10.239.71.46/32	10.239.71.46 – 10.239.71.46	10.239.71.46
48	10.239.71.47/32	10.239.71.47 – 10.239.71.47	10.239.71.47
49	10.239.71.48/32	10.239.71.48 – 10.239.71.48	10.239.71.48
50	10.239.71.49/32	10.239.71.49 – 10.239.71.49	10.239.71.49
51	10.239.71.50/32	10.239.71.50 – 10.239.71.50	10.239.71.50
52	10.239.71.51/32	10.239.71.51 – 10.239.71.51	10.239.71.51
53	10.239.71.52/32	10.239.71.52 – 10.239.71.52	10.239.71.52
54	10.239.71.53/32	10.239.71.53 – 10.239.71.53	10.239.71.53
55	10.239.71.54/32	10.239.71.54 – 10.239.71.54	10.239.71.54
56	10.239.71.55/32	10.239.71.55 – 10.239.71.55	10.239.71.55
57	10.239.71.56/32	10.239.71.56 – 10.239.71.56	10.239.71.56
58	10.239.71.57/32	10.239.71.57 – 10.239.71.57	10.239.71.57
59	10.239.71.58/32	10.239.71.58 – 10.239.71.58	10.239.71.58
60	10.239.71.59/32	10.239.71.59 – 10.239.71.59	10.239.71.59
61	10.239.71.60/32	10.239.71.60 – 10.239.71.60	10.239.71.60
62	10.239.71.61/32	10.239.71.61 – 10.239.71.61	10.239.71.61
63	10.239.71.62/32	10.239.71.62 – 10.239.71.62	10.239.71.62
64	10.239.71.63/32	10.239.71.63 – 10.239.71.63	10.239.71.63
65	10.239.71.64/32	10.239.71.64 – 10.239.71.64	10.239.71.64
66	10.239.71.65/32	10.239.71.65 – 10.239.71.65	10.239.71.65
67	10.239.71.66/32	10.239.71.66 – 10.239.71.66	10.239.71.66
68	10.239.71.67/32	10.239.71.67 – 10.239.71.67	10.239.71.67
69	10.239.71.68/32	10.239.71.68 – 10.239.71.68	10.239.71.68
70	10.239.71.69/32	10.239.71.69 – 10.239.71.69	10.239.71.69
71	10.239.71.70/32	10.239.71.70 – 10.239.71.70	10.239.71.70
72	10.239.71.71/32	10.239.71.71 – 10.239.71.71	10.239.71.71
73	10.239.71.72/32	10.239.71.72 – 10.239.71.72	10.239.71.72
74	10.239.71.73/32	10.239.71.73 – 10.239.71.73	10.239.71.73
75	10.239.71.74/32	10.239.71.74 – 10.239.71.74	10.239.71.74
76	10.239.71.75/32	10.239.71.75 – 10.239.71.75	10.239.71.75
77	10.239.71.76/32	10.239.71.76 – 10.239.71.76	10.239.71.76
78	10.239.71.77/32	10.239.71.77 – 10.239.71.77	10.239.71.77
79	10.239.71.78/32	10.239.71.78 – 10.239.71.78	10.239.71.78
80	10.239.71.79/32	10.239.71.79 – 10.239.71.79	10.239.71.79
81	10.239.71.80/32	10.239.71.80 – 10.239.71.80	10.239.71.80
82	10.239.71.81/32	10.239.71.81 – 10.239.71.81	10.239.71.81
83	10.239.71.82/32	10.239.71.82 – 10.239.71.82	10.239.71.82
84	10.239.71.83/32	10.239.71.83 – 10.239.71.83	10.239.71.83
85	10.239.71.84/32	10.239.71.84 – 10.239.71.84	10.239.71.84
86	10.239.71.85/32	10.239.71.85 – 10.239.71.85	10.239.71.85
87	10.239.71.86/32	10.239.71.86 – 10.239.71.86	10.239.71.86
88	10.239.71.87/32	10.239.71.87 – 10.239.71.87	10.239.71.87
89	10.239.71.88/32	10.239.71.88 – 10.239.71.88	10.239.71.88
90	10.239.71.89/32	10.239.71.89 – 10.239.71.89	10.239.71.89
91	10.239.71.90/32	10.239.71.90 – 10.239.71.90	10.239.71.90
92	10.239.71.91/32	10.239.71.91 – 10.239.71.91	10.239.71.91
93	10.239.71.92/32	10.239.71.92 – 10.239.71.92	10.239.71.92
94	10.239.71.93/32	10.239.71.93 – 10.239.71.93	10.239.71.93
95	10.239.71.94/32	10.239.71.94 – 10.239.71.94	10.239.71.94
96	10.239.71.95/32	10.239.71.95 – 10.239.71.95	10.239.71.95
97	10.239.71.96/32	10.239.71.96 – 10.239.71.96	10.239.71.96
98	10.239.71.97/32	10.239.71.97 – 10.239.71.97	10.239.71.97
99	10.239.71.98/32	10.239.71.98 – 10.239.71.98	10.239.71.98
100	10.239.71.99/32	10.239.71.99 – 10.239.71.99	10.239.71.99
101	10.239.71.100/32	10.239.71.100 – 10.239.71.100	10.239.71.100
102	10.239.71.101/32	10.239.71.101 – 10.239.71.101	10.239.71.101
103	10.239.71.102/32	10.239.71.102 – 10.239.71.102	10.239.71.102
104	10.239.71.103/32	10.239.71.103 – 10.239.71.103	10.239.71.103
105	10.239.71.104/32	10.239.71.104 – 10.239.71.104	10.239.71.104
106	10.239.71.105/32	10.239.71.105 – 10.239.71.105	10.239.71.105
107	10.239.71.106/32	10.239.71.106 – 10.239.71.106	10.239.71.106
108	10.239.71.107/32	10.239.71.107 – 10.239.71.107	10.239.71.107
109	10.239.71.108/32	10.239.71.108 – 10.239.71.108	10.239.71.108
110	10.239.71.109/32	10.239.71.109 – 10.239.71.109	10.239.71.109
111	10.239.71.110/32	10.239.71.110 – 10.239.71.110	10.239.71.110
112	10.239.71.111/32	10.239.71.111 – 10.239.71.111	10.239.71.111
113	10.239.71.112/32	10.239.71.112 – 10.239.71.112	10.239.71.112
114	10.239.71.113/32	10.239.71.113 – 10.239.71.113	10.239.71.113
115	10.239.71.114/32	10.239.71.114 – 10.239.71.114	10.239.71.114
116	10.239.71.115/32	10.239.71.115 – 10.239.71.115	10.239.71.115
117	10.239.71.116/32	10.239.71.116 – 10.239.71.116	10.239.71.116
118	10.239.71.117/32	10.239.71.117 – 10.239.71.117	10.239.71.117
119	10.239.71.118/32	10.239.71.118 – 10.239.71.118	10.239.71.118
120	10.239.71.119/32	10.239.71.119 – 10.239.71.119	10.239.71.119
121	10.239.71.120/32	10.239.71.120 – 10.239.71.120	10.239.71.120
122	10.239.71.121/32	10.239.71.121 – 10.239.71.121	10.239.71.121
123	10.239.71.122/32	10.239.71.122 – 10.239.71.122	10.239.71.122
124	10.239.71.123/32	10.239.71.123 – 10.239.71.123	10.239.71.123
125	10.239.71.124/32	10.239.71.124 – 10.239.71.124	10.239.71.124
126	10.239.71.125/32	10.239.71.125 – 10.239.71.125	10.239.71.125
127	10.239.71.126/32	10.239.71.126 – 10.239.71.126	10.239.71.126
128	10.239.71.127/32	10.239.71.127 – 10.239.71.127	10.239.71.127

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 →