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)10.0.37.0/25

network10.0.37.0/25

broadcast10.0.37.127

first host10.0.37.1

last host10.0.37.126

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.0.37.0/25

address00001010.00000000.00100101.00000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000000.00100101.00000000

broadcast00001010.00000000.00100101.01111111

green = network part, grey = host part

hex0x0a002500

decimal167781632

reverse dns0.37.0.10.in-addr.arpa

ipv4-mapped::ffff:a00:2500

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.0.37.0/32	10.0.37.0 – 10.0.37.0	10.0.37.0
2	10.0.37.1/32	10.0.37.1 – 10.0.37.1	10.0.37.1
3	10.0.37.2/32	10.0.37.2 – 10.0.37.2	10.0.37.2
4	10.0.37.3/32	10.0.37.3 – 10.0.37.3	10.0.37.3
5	10.0.37.4/32	10.0.37.4 – 10.0.37.4	10.0.37.4
6	10.0.37.5/32	10.0.37.5 – 10.0.37.5	10.0.37.5
7	10.0.37.6/32	10.0.37.6 – 10.0.37.6	10.0.37.6
8	10.0.37.7/32	10.0.37.7 – 10.0.37.7	10.0.37.7
9	10.0.37.8/32	10.0.37.8 – 10.0.37.8	10.0.37.8
10	10.0.37.9/32	10.0.37.9 – 10.0.37.9	10.0.37.9
11	10.0.37.10/32	10.0.37.10 – 10.0.37.10	10.0.37.10
12	10.0.37.11/32	10.0.37.11 – 10.0.37.11	10.0.37.11
13	10.0.37.12/32	10.0.37.12 – 10.0.37.12	10.0.37.12
14	10.0.37.13/32	10.0.37.13 – 10.0.37.13	10.0.37.13
15	10.0.37.14/32	10.0.37.14 – 10.0.37.14	10.0.37.14
16	10.0.37.15/32	10.0.37.15 – 10.0.37.15	10.0.37.15
17	10.0.37.16/32	10.0.37.16 – 10.0.37.16	10.0.37.16
18	10.0.37.17/32	10.0.37.17 – 10.0.37.17	10.0.37.17
19	10.0.37.18/32	10.0.37.18 – 10.0.37.18	10.0.37.18
20	10.0.37.19/32	10.0.37.19 – 10.0.37.19	10.0.37.19
21	10.0.37.20/32	10.0.37.20 – 10.0.37.20	10.0.37.20
22	10.0.37.21/32	10.0.37.21 – 10.0.37.21	10.0.37.21
23	10.0.37.22/32	10.0.37.22 – 10.0.37.22	10.0.37.22
24	10.0.37.23/32	10.0.37.23 – 10.0.37.23	10.0.37.23
25	10.0.37.24/32	10.0.37.24 – 10.0.37.24	10.0.37.24
26	10.0.37.25/32	10.0.37.25 – 10.0.37.25	10.0.37.25
27	10.0.37.26/32	10.0.37.26 – 10.0.37.26	10.0.37.26
28	10.0.37.27/32	10.0.37.27 – 10.0.37.27	10.0.37.27
29	10.0.37.28/32	10.0.37.28 – 10.0.37.28	10.0.37.28
30	10.0.37.29/32	10.0.37.29 – 10.0.37.29	10.0.37.29
31	10.0.37.30/32	10.0.37.30 – 10.0.37.30	10.0.37.30
32	10.0.37.31/32	10.0.37.31 – 10.0.37.31	10.0.37.31
33	10.0.37.32/32	10.0.37.32 – 10.0.37.32	10.0.37.32
34	10.0.37.33/32	10.0.37.33 – 10.0.37.33	10.0.37.33
35	10.0.37.34/32	10.0.37.34 – 10.0.37.34	10.0.37.34
36	10.0.37.35/32	10.0.37.35 – 10.0.37.35	10.0.37.35
37	10.0.37.36/32	10.0.37.36 – 10.0.37.36	10.0.37.36
38	10.0.37.37/32	10.0.37.37 – 10.0.37.37	10.0.37.37
39	10.0.37.38/32	10.0.37.38 – 10.0.37.38	10.0.37.38
40	10.0.37.39/32	10.0.37.39 – 10.0.37.39	10.0.37.39
41	10.0.37.40/32	10.0.37.40 – 10.0.37.40	10.0.37.40
42	10.0.37.41/32	10.0.37.41 – 10.0.37.41	10.0.37.41
43	10.0.37.42/32	10.0.37.42 – 10.0.37.42	10.0.37.42
44	10.0.37.43/32	10.0.37.43 – 10.0.37.43	10.0.37.43
45	10.0.37.44/32	10.0.37.44 – 10.0.37.44	10.0.37.44
46	10.0.37.45/32	10.0.37.45 – 10.0.37.45	10.0.37.45
47	10.0.37.46/32	10.0.37.46 – 10.0.37.46	10.0.37.46
48	10.0.37.47/32	10.0.37.47 – 10.0.37.47	10.0.37.47
49	10.0.37.48/32	10.0.37.48 – 10.0.37.48	10.0.37.48
50	10.0.37.49/32	10.0.37.49 – 10.0.37.49	10.0.37.49
51	10.0.37.50/32	10.0.37.50 – 10.0.37.50	10.0.37.50
52	10.0.37.51/32	10.0.37.51 – 10.0.37.51	10.0.37.51
53	10.0.37.52/32	10.0.37.52 – 10.0.37.52	10.0.37.52
54	10.0.37.53/32	10.0.37.53 – 10.0.37.53	10.0.37.53
55	10.0.37.54/32	10.0.37.54 – 10.0.37.54	10.0.37.54
56	10.0.37.55/32	10.0.37.55 – 10.0.37.55	10.0.37.55
57	10.0.37.56/32	10.0.37.56 – 10.0.37.56	10.0.37.56
58	10.0.37.57/32	10.0.37.57 – 10.0.37.57	10.0.37.57
59	10.0.37.58/32	10.0.37.58 – 10.0.37.58	10.0.37.58
60	10.0.37.59/32	10.0.37.59 – 10.0.37.59	10.0.37.59
61	10.0.37.60/32	10.0.37.60 – 10.0.37.60	10.0.37.60
62	10.0.37.61/32	10.0.37.61 – 10.0.37.61	10.0.37.61
63	10.0.37.62/32	10.0.37.62 – 10.0.37.62	10.0.37.62
64	10.0.37.63/32	10.0.37.63 – 10.0.37.63	10.0.37.63
65	10.0.37.64/32	10.0.37.64 – 10.0.37.64	10.0.37.64
66	10.0.37.65/32	10.0.37.65 – 10.0.37.65	10.0.37.65
67	10.0.37.66/32	10.0.37.66 – 10.0.37.66	10.0.37.66
68	10.0.37.67/32	10.0.37.67 – 10.0.37.67	10.0.37.67
69	10.0.37.68/32	10.0.37.68 – 10.0.37.68	10.0.37.68
70	10.0.37.69/32	10.0.37.69 – 10.0.37.69	10.0.37.69
71	10.0.37.70/32	10.0.37.70 – 10.0.37.70	10.0.37.70
72	10.0.37.71/32	10.0.37.71 – 10.0.37.71	10.0.37.71
73	10.0.37.72/32	10.0.37.72 – 10.0.37.72	10.0.37.72
74	10.0.37.73/32	10.0.37.73 – 10.0.37.73	10.0.37.73
75	10.0.37.74/32	10.0.37.74 – 10.0.37.74	10.0.37.74
76	10.0.37.75/32	10.0.37.75 – 10.0.37.75	10.0.37.75
77	10.0.37.76/32	10.0.37.76 – 10.0.37.76	10.0.37.76
78	10.0.37.77/32	10.0.37.77 – 10.0.37.77	10.0.37.77
79	10.0.37.78/32	10.0.37.78 – 10.0.37.78	10.0.37.78
80	10.0.37.79/32	10.0.37.79 – 10.0.37.79	10.0.37.79
81	10.0.37.80/32	10.0.37.80 – 10.0.37.80	10.0.37.80
82	10.0.37.81/32	10.0.37.81 – 10.0.37.81	10.0.37.81
83	10.0.37.82/32	10.0.37.82 – 10.0.37.82	10.0.37.82
84	10.0.37.83/32	10.0.37.83 – 10.0.37.83	10.0.37.83
85	10.0.37.84/32	10.0.37.84 – 10.0.37.84	10.0.37.84
86	10.0.37.85/32	10.0.37.85 – 10.0.37.85	10.0.37.85
87	10.0.37.86/32	10.0.37.86 – 10.0.37.86	10.0.37.86
88	10.0.37.87/32	10.0.37.87 – 10.0.37.87	10.0.37.87
89	10.0.37.88/32	10.0.37.88 – 10.0.37.88	10.0.37.88
90	10.0.37.89/32	10.0.37.89 – 10.0.37.89	10.0.37.89
91	10.0.37.90/32	10.0.37.90 – 10.0.37.90	10.0.37.90
92	10.0.37.91/32	10.0.37.91 – 10.0.37.91	10.0.37.91
93	10.0.37.92/32	10.0.37.92 – 10.0.37.92	10.0.37.92
94	10.0.37.93/32	10.0.37.93 – 10.0.37.93	10.0.37.93
95	10.0.37.94/32	10.0.37.94 – 10.0.37.94	10.0.37.94
96	10.0.37.95/32	10.0.37.95 – 10.0.37.95	10.0.37.95
97	10.0.37.96/32	10.0.37.96 – 10.0.37.96	10.0.37.96
98	10.0.37.97/32	10.0.37.97 – 10.0.37.97	10.0.37.97
99	10.0.37.98/32	10.0.37.98 – 10.0.37.98	10.0.37.98
100	10.0.37.99/32	10.0.37.99 – 10.0.37.99	10.0.37.99
101	10.0.37.100/32	10.0.37.100 – 10.0.37.100	10.0.37.100
102	10.0.37.101/32	10.0.37.101 – 10.0.37.101	10.0.37.101
103	10.0.37.102/32	10.0.37.102 – 10.0.37.102	10.0.37.102
104	10.0.37.103/32	10.0.37.103 – 10.0.37.103	10.0.37.103
105	10.0.37.104/32	10.0.37.104 – 10.0.37.104	10.0.37.104
106	10.0.37.105/32	10.0.37.105 – 10.0.37.105	10.0.37.105
107	10.0.37.106/32	10.0.37.106 – 10.0.37.106	10.0.37.106
108	10.0.37.107/32	10.0.37.107 – 10.0.37.107	10.0.37.107
109	10.0.37.108/32	10.0.37.108 – 10.0.37.108	10.0.37.108
110	10.0.37.109/32	10.0.37.109 – 10.0.37.109	10.0.37.109
111	10.0.37.110/32	10.0.37.110 – 10.0.37.110	10.0.37.110
112	10.0.37.111/32	10.0.37.111 – 10.0.37.111	10.0.37.111
113	10.0.37.112/32	10.0.37.112 – 10.0.37.112	10.0.37.112
114	10.0.37.113/32	10.0.37.113 – 10.0.37.113	10.0.37.113
115	10.0.37.114/32	10.0.37.114 – 10.0.37.114	10.0.37.114
116	10.0.37.115/32	10.0.37.115 – 10.0.37.115	10.0.37.115
117	10.0.37.116/32	10.0.37.116 – 10.0.37.116	10.0.37.116
118	10.0.37.117/32	10.0.37.117 – 10.0.37.117	10.0.37.117
119	10.0.37.118/32	10.0.37.118 – 10.0.37.118	10.0.37.118
120	10.0.37.119/32	10.0.37.119 – 10.0.37.119	10.0.37.119
121	10.0.37.120/32	10.0.37.120 – 10.0.37.120	10.0.37.120
122	10.0.37.121/32	10.0.37.121 – 10.0.37.121	10.0.37.121
123	10.0.37.122/32	10.0.37.122 – 10.0.37.122	10.0.37.122
124	10.0.37.123/32	10.0.37.123 – 10.0.37.123	10.0.37.123
125	10.0.37.124/32	10.0.37.124 – 10.0.37.124	10.0.37.124
126	10.0.37.125/32	10.0.37.125 – 10.0.37.125	10.0.37.125
127	10.0.37.126/32	10.0.37.126 – 10.0.37.126	10.0.37.126
128	10.0.37.127/32	10.0.37.127 – 10.0.37.127	10.0.37.127

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 →