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)10.0.91.0/25

network10.0.91.0/25

broadcast10.0.91.127

first host10.0.91.1

last host10.0.91.126

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.0.91.0/25

address00001010.00000000.01011011.00000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000000.01011011.00000000

broadcast00001010.00000000.01011011.01111111

green = network part, grey = host part

hex0x0a005b00

decimal167795456

reverse dns0.91.0.10.in-addr.arpa

ipv4-mapped::ffff:a00:5b00

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.0.91.0/32	10.0.91.0 – 10.0.91.0	10.0.91.0
2	10.0.91.1/32	10.0.91.1 – 10.0.91.1	10.0.91.1
3	10.0.91.2/32	10.0.91.2 – 10.0.91.2	10.0.91.2
4	10.0.91.3/32	10.0.91.3 – 10.0.91.3	10.0.91.3
5	10.0.91.4/32	10.0.91.4 – 10.0.91.4	10.0.91.4
6	10.0.91.5/32	10.0.91.5 – 10.0.91.5	10.0.91.5
7	10.0.91.6/32	10.0.91.6 – 10.0.91.6	10.0.91.6
8	10.0.91.7/32	10.0.91.7 – 10.0.91.7	10.0.91.7
9	10.0.91.8/32	10.0.91.8 – 10.0.91.8	10.0.91.8
10	10.0.91.9/32	10.0.91.9 – 10.0.91.9	10.0.91.9
11	10.0.91.10/32	10.0.91.10 – 10.0.91.10	10.0.91.10
12	10.0.91.11/32	10.0.91.11 – 10.0.91.11	10.0.91.11
13	10.0.91.12/32	10.0.91.12 – 10.0.91.12	10.0.91.12
14	10.0.91.13/32	10.0.91.13 – 10.0.91.13	10.0.91.13
15	10.0.91.14/32	10.0.91.14 – 10.0.91.14	10.0.91.14
16	10.0.91.15/32	10.0.91.15 – 10.0.91.15	10.0.91.15
17	10.0.91.16/32	10.0.91.16 – 10.0.91.16	10.0.91.16
18	10.0.91.17/32	10.0.91.17 – 10.0.91.17	10.0.91.17
19	10.0.91.18/32	10.0.91.18 – 10.0.91.18	10.0.91.18
20	10.0.91.19/32	10.0.91.19 – 10.0.91.19	10.0.91.19
21	10.0.91.20/32	10.0.91.20 – 10.0.91.20	10.0.91.20
22	10.0.91.21/32	10.0.91.21 – 10.0.91.21	10.0.91.21
23	10.0.91.22/32	10.0.91.22 – 10.0.91.22	10.0.91.22
24	10.0.91.23/32	10.0.91.23 – 10.0.91.23	10.0.91.23
25	10.0.91.24/32	10.0.91.24 – 10.0.91.24	10.0.91.24
26	10.0.91.25/32	10.0.91.25 – 10.0.91.25	10.0.91.25
27	10.0.91.26/32	10.0.91.26 – 10.0.91.26	10.0.91.26
28	10.0.91.27/32	10.0.91.27 – 10.0.91.27	10.0.91.27
29	10.0.91.28/32	10.0.91.28 – 10.0.91.28	10.0.91.28
30	10.0.91.29/32	10.0.91.29 – 10.0.91.29	10.0.91.29
31	10.0.91.30/32	10.0.91.30 – 10.0.91.30	10.0.91.30
32	10.0.91.31/32	10.0.91.31 – 10.0.91.31	10.0.91.31
33	10.0.91.32/32	10.0.91.32 – 10.0.91.32	10.0.91.32
34	10.0.91.33/32	10.0.91.33 – 10.0.91.33	10.0.91.33
35	10.0.91.34/32	10.0.91.34 – 10.0.91.34	10.0.91.34
36	10.0.91.35/32	10.0.91.35 – 10.0.91.35	10.0.91.35
37	10.0.91.36/32	10.0.91.36 – 10.0.91.36	10.0.91.36
38	10.0.91.37/32	10.0.91.37 – 10.0.91.37	10.0.91.37
39	10.0.91.38/32	10.0.91.38 – 10.0.91.38	10.0.91.38
40	10.0.91.39/32	10.0.91.39 – 10.0.91.39	10.0.91.39
41	10.0.91.40/32	10.0.91.40 – 10.0.91.40	10.0.91.40
42	10.0.91.41/32	10.0.91.41 – 10.0.91.41	10.0.91.41
43	10.0.91.42/32	10.0.91.42 – 10.0.91.42	10.0.91.42
44	10.0.91.43/32	10.0.91.43 – 10.0.91.43	10.0.91.43
45	10.0.91.44/32	10.0.91.44 – 10.0.91.44	10.0.91.44
46	10.0.91.45/32	10.0.91.45 – 10.0.91.45	10.0.91.45
47	10.0.91.46/32	10.0.91.46 – 10.0.91.46	10.0.91.46
48	10.0.91.47/32	10.0.91.47 – 10.0.91.47	10.0.91.47
49	10.0.91.48/32	10.0.91.48 – 10.0.91.48	10.0.91.48
50	10.0.91.49/32	10.0.91.49 – 10.0.91.49	10.0.91.49
51	10.0.91.50/32	10.0.91.50 – 10.0.91.50	10.0.91.50
52	10.0.91.51/32	10.0.91.51 – 10.0.91.51	10.0.91.51
53	10.0.91.52/32	10.0.91.52 – 10.0.91.52	10.0.91.52
54	10.0.91.53/32	10.0.91.53 – 10.0.91.53	10.0.91.53
55	10.0.91.54/32	10.0.91.54 – 10.0.91.54	10.0.91.54
56	10.0.91.55/32	10.0.91.55 – 10.0.91.55	10.0.91.55
57	10.0.91.56/32	10.0.91.56 – 10.0.91.56	10.0.91.56
58	10.0.91.57/32	10.0.91.57 – 10.0.91.57	10.0.91.57
59	10.0.91.58/32	10.0.91.58 – 10.0.91.58	10.0.91.58
60	10.0.91.59/32	10.0.91.59 – 10.0.91.59	10.0.91.59
61	10.0.91.60/32	10.0.91.60 – 10.0.91.60	10.0.91.60
62	10.0.91.61/32	10.0.91.61 – 10.0.91.61	10.0.91.61
63	10.0.91.62/32	10.0.91.62 – 10.0.91.62	10.0.91.62
64	10.0.91.63/32	10.0.91.63 – 10.0.91.63	10.0.91.63
65	10.0.91.64/32	10.0.91.64 – 10.0.91.64	10.0.91.64
66	10.0.91.65/32	10.0.91.65 – 10.0.91.65	10.0.91.65
67	10.0.91.66/32	10.0.91.66 – 10.0.91.66	10.0.91.66
68	10.0.91.67/32	10.0.91.67 – 10.0.91.67	10.0.91.67
69	10.0.91.68/32	10.0.91.68 – 10.0.91.68	10.0.91.68
70	10.0.91.69/32	10.0.91.69 – 10.0.91.69	10.0.91.69
71	10.0.91.70/32	10.0.91.70 – 10.0.91.70	10.0.91.70
72	10.0.91.71/32	10.0.91.71 – 10.0.91.71	10.0.91.71
73	10.0.91.72/32	10.0.91.72 – 10.0.91.72	10.0.91.72
74	10.0.91.73/32	10.0.91.73 – 10.0.91.73	10.0.91.73
75	10.0.91.74/32	10.0.91.74 – 10.0.91.74	10.0.91.74
76	10.0.91.75/32	10.0.91.75 – 10.0.91.75	10.0.91.75
77	10.0.91.76/32	10.0.91.76 – 10.0.91.76	10.0.91.76
78	10.0.91.77/32	10.0.91.77 – 10.0.91.77	10.0.91.77
79	10.0.91.78/32	10.0.91.78 – 10.0.91.78	10.0.91.78
80	10.0.91.79/32	10.0.91.79 – 10.0.91.79	10.0.91.79
81	10.0.91.80/32	10.0.91.80 – 10.0.91.80	10.0.91.80
82	10.0.91.81/32	10.0.91.81 – 10.0.91.81	10.0.91.81
83	10.0.91.82/32	10.0.91.82 – 10.0.91.82	10.0.91.82
84	10.0.91.83/32	10.0.91.83 – 10.0.91.83	10.0.91.83
85	10.0.91.84/32	10.0.91.84 – 10.0.91.84	10.0.91.84
86	10.0.91.85/32	10.0.91.85 – 10.0.91.85	10.0.91.85
87	10.0.91.86/32	10.0.91.86 – 10.0.91.86	10.0.91.86
88	10.0.91.87/32	10.0.91.87 – 10.0.91.87	10.0.91.87
89	10.0.91.88/32	10.0.91.88 – 10.0.91.88	10.0.91.88
90	10.0.91.89/32	10.0.91.89 – 10.0.91.89	10.0.91.89
91	10.0.91.90/32	10.0.91.90 – 10.0.91.90	10.0.91.90
92	10.0.91.91/32	10.0.91.91 – 10.0.91.91	10.0.91.91
93	10.0.91.92/32	10.0.91.92 – 10.0.91.92	10.0.91.92
94	10.0.91.93/32	10.0.91.93 – 10.0.91.93	10.0.91.93
95	10.0.91.94/32	10.0.91.94 – 10.0.91.94	10.0.91.94
96	10.0.91.95/32	10.0.91.95 – 10.0.91.95	10.0.91.95
97	10.0.91.96/32	10.0.91.96 – 10.0.91.96	10.0.91.96
98	10.0.91.97/32	10.0.91.97 – 10.0.91.97	10.0.91.97
99	10.0.91.98/32	10.0.91.98 – 10.0.91.98	10.0.91.98
100	10.0.91.99/32	10.0.91.99 – 10.0.91.99	10.0.91.99
101	10.0.91.100/32	10.0.91.100 – 10.0.91.100	10.0.91.100
102	10.0.91.101/32	10.0.91.101 – 10.0.91.101	10.0.91.101
103	10.0.91.102/32	10.0.91.102 – 10.0.91.102	10.0.91.102
104	10.0.91.103/32	10.0.91.103 – 10.0.91.103	10.0.91.103
105	10.0.91.104/32	10.0.91.104 – 10.0.91.104	10.0.91.104
106	10.0.91.105/32	10.0.91.105 – 10.0.91.105	10.0.91.105
107	10.0.91.106/32	10.0.91.106 – 10.0.91.106	10.0.91.106
108	10.0.91.107/32	10.0.91.107 – 10.0.91.107	10.0.91.107
109	10.0.91.108/32	10.0.91.108 – 10.0.91.108	10.0.91.108
110	10.0.91.109/32	10.0.91.109 – 10.0.91.109	10.0.91.109
111	10.0.91.110/32	10.0.91.110 – 10.0.91.110	10.0.91.110
112	10.0.91.111/32	10.0.91.111 – 10.0.91.111	10.0.91.111
113	10.0.91.112/32	10.0.91.112 – 10.0.91.112	10.0.91.112
114	10.0.91.113/32	10.0.91.113 – 10.0.91.113	10.0.91.113
115	10.0.91.114/32	10.0.91.114 – 10.0.91.114	10.0.91.114
116	10.0.91.115/32	10.0.91.115 – 10.0.91.115	10.0.91.115
117	10.0.91.116/32	10.0.91.116 – 10.0.91.116	10.0.91.116
118	10.0.91.117/32	10.0.91.117 – 10.0.91.117	10.0.91.117
119	10.0.91.118/32	10.0.91.118 – 10.0.91.118	10.0.91.118
120	10.0.91.119/32	10.0.91.119 – 10.0.91.119	10.0.91.119
121	10.0.91.120/32	10.0.91.120 – 10.0.91.120	10.0.91.120
122	10.0.91.121/32	10.0.91.121 – 10.0.91.121	10.0.91.121
123	10.0.91.122/32	10.0.91.122 – 10.0.91.122	10.0.91.122
124	10.0.91.123/32	10.0.91.123 – 10.0.91.123	10.0.91.123
125	10.0.91.124/32	10.0.91.124 – 10.0.91.124	10.0.91.124
126	10.0.91.125/32	10.0.91.125 – 10.0.91.125	10.0.91.125
127	10.0.91.126/32	10.0.91.126 – 10.0.91.126	10.0.91.126
128	10.0.91.127/32	10.0.91.127 – 10.0.91.127	10.0.91.127

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 →