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)10.3.27.0/25

network10.3.27.0/25

broadcast10.3.27.127

first host10.3.27.1

last host10.3.27.126

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.3.27.0/25

address00001010.00000011.00011011.00000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000011.00011011.00000000

broadcast00001010.00000011.00011011.01111111

green = network part, grey = host part

hex0x0a031b00

decimal167975680

reverse dns0.27.3.10.in-addr.arpa

ipv4-mapped::ffff:a03:1b00

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.3.27.0/32	10.3.27.0 – 10.3.27.0	10.3.27.0
2	10.3.27.1/32	10.3.27.1 – 10.3.27.1	10.3.27.1
3	10.3.27.2/32	10.3.27.2 – 10.3.27.2	10.3.27.2
4	10.3.27.3/32	10.3.27.3 – 10.3.27.3	10.3.27.3
5	10.3.27.4/32	10.3.27.4 – 10.3.27.4	10.3.27.4
6	10.3.27.5/32	10.3.27.5 – 10.3.27.5	10.3.27.5
7	10.3.27.6/32	10.3.27.6 – 10.3.27.6	10.3.27.6
8	10.3.27.7/32	10.3.27.7 – 10.3.27.7	10.3.27.7
9	10.3.27.8/32	10.3.27.8 – 10.3.27.8	10.3.27.8
10	10.3.27.9/32	10.3.27.9 – 10.3.27.9	10.3.27.9
11	10.3.27.10/32	10.3.27.10 – 10.3.27.10	10.3.27.10
12	10.3.27.11/32	10.3.27.11 – 10.3.27.11	10.3.27.11
13	10.3.27.12/32	10.3.27.12 – 10.3.27.12	10.3.27.12
14	10.3.27.13/32	10.3.27.13 – 10.3.27.13	10.3.27.13
15	10.3.27.14/32	10.3.27.14 – 10.3.27.14	10.3.27.14
16	10.3.27.15/32	10.3.27.15 – 10.3.27.15	10.3.27.15
17	10.3.27.16/32	10.3.27.16 – 10.3.27.16	10.3.27.16
18	10.3.27.17/32	10.3.27.17 – 10.3.27.17	10.3.27.17
19	10.3.27.18/32	10.3.27.18 – 10.3.27.18	10.3.27.18
20	10.3.27.19/32	10.3.27.19 – 10.3.27.19	10.3.27.19
21	10.3.27.20/32	10.3.27.20 – 10.3.27.20	10.3.27.20
22	10.3.27.21/32	10.3.27.21 – 10.3.27.21	10.3.27.21
23	10.3.27.22/32	10.3.27.22 – 10.3.27.22	10.3.27.22
24	10.3.27.23/32	10.3.27.23 – 10.3.27.23	10.3.27.23
25	10.3.27.24/32	10.3.27.24 – 10.3.27.24	10.3.27.24
26	10.3.27.25/32	10.3.27.25 – 10.3.27.25	10.3.27.25
27	10.3.27.26/32	10.3.27.26 – 10.3.27.26	10.3.27.26
28	10.3.27.27/32	10.3.27.27 – 10.3.27.27	10.3.27.27
29	10.3.27.28/32	10.3.27.28 – 10.3.27.28	10.3.27.28
30	10.3.27.29/32	10.3.27.29 – 10.3.27.29	10.3.27.29
31	10.3.27.30/32	10.3.27.30 – 10.3.27.30	10.3.27.30
32	10.3.27.31/32	10.3.27.31 – 10.3.27.31	10.3.27.31
33	10.3.27.32/32	10.3.27.32 – 10.3.27.32	10.3.27.32
34	10.3.27.33/32	10.3.27.33 – 10.3.27.33	10.3.27.33
35	10.3.27.34/32	10.3.27.34 – 10.3.27.34	10.3.27.34
36	10.3.27.35/32	10.3.27.35 – 10.3.27.35	10.3.27.35
37	10.3.27.36/32	10.3.27.36 – 10.3.27.36	10.3.27.36
38	10.3.27.37/32	10.3.27.37 – 10.3.27.37	10.3.27.37
39	10.3.27.38/32	10.3.27.38 – 10.3.27.38	10.3.27.38
40	10.3.27.39/32	10.3.27.39 – 10.3.27.39	10.3.27.39
41	10.3.27.40/32	10.3.27.40 – 10.3.27.40	10.3.27.40
42	10.3.27.41/32	10.3.27.41 – 10.3.27.41	10.3.27.41
43	10.3.27.42/32	10.3.27.42 – 10.3.27.42	10.3.27.42
44	10.3.27.43/32	10.3.27.43 – 10.3.27.43	10.3.27.43
45	10.3.27.44/32	10.3.27.44 – 10.3.27.44	10.3.27.44
46	10.3.27.45/32	10.3.27.45 – 10.3.27.45	10.3.27.45
47	10.3.27.46/32	10.3.27.46 – 10.3.27.46	10.3.27.46
48	10.3.27.47/32	10.3.27.47 – 10.3.27.47	10.3.27.47
49	10.3.27.48/32	10.3.27.48 – 10.3.27.48	10.3.27.48
50	10.3.27.49/32	10.3.27.49 – 10.3.27.49	10.3.27.49
51	10.3.27.50/32	10.3.27.50 – 10.3.27.50	10.3.27.50
52	10.3.27.51/32	10.3.27.51 – 10.3.27.51	10.3.27.51
53	10.3.27.52/32	10.3.27.52 – 10.3.27.52	10.3.27.52
54	10.3.27.53/32	10.3.27.53 – 10.3.27.53	10.3.27.53
55	10.3.27.54/32	10.3.27.54 – 10.3.27.54	10.3.27.54
56	10.3.27.55/32	10.3.27.55 – 10.3.27.55	10.3.27.55
57	10.3.27.56/32	10.3.27.56 – 10.3.27.56	10.3.27.56
58	10.3.27.57/32	10.3.27.57 – 10.3.27.57	10.3.27.57
59	10.3.27.58/32	10.3.27.58 – 10.3.27.58	10.3.27.58
60	10.3.27.59/32	10.3.27.59 – 10.3.27.59	10.3.27.59
61	10.3.27.60/32	10.3.27.60 – 10.3.27.60	10.3.27.60
62	10.3.27.61/32	10.3.27.61 – 10.3.27.61	10.3.27.61
63	10.3.27.62/32	10.3.27.62 – 10.3.27.62	10.3.27.62
64	10.3.27.63/32	10.3.27.63 – 10.3.27.63	10.3.27.63
65	10.3.27.64/32	10.3.27.64 – 10.3.27.64	10.3.27.64
66	10.3.27.65/32	10.3.27.65 – 10.3.27.65	10.3.27.65
67	10.3.27.66/32	10.3.27.66 – 10.3.27.66	10.3.27.66
68	10.3.27.67/32	10.3.27.67 – 10.3.27.67	10.3.27.67
69	10.3.27.68/32	10.3.27.68 – 10.3.27.68	10.3.27.68
70	10.3.27.69/32	10.3.27.69 – 10.3.27.69	10.3.27.69
71	10.3.27.70/32	10.3.27.70 – 10.3.27.70	10.3.27.70
72	10.3.27.71/32	10.3.27.71 – 10.3.27.71	10.3.27.71
73	10.3.27.72/32	10.3.27.72 – 10.3.27.72	10.3.27.72
74	10.3.27.73/32	10.3.27.73 – 10.3.27.73	10.3.27.73
75	10.3.27.74/32	10.3.27.74 – 10.3.27.74	10.3.27.74
76	10.3.27.75/32	10.3.27.75 – 10.3.27.75	10.3.27.75
77	10.3.27.76/32	10.3.27.76 – 10.3.27.76	10.3.27.76
78	10.3.27.77/32	10.3.27.77 – 10.3.27.77	10.3.27.77
79	10.3.27.78/32	10.3.27.78 – 10.3.27.78	10.3.27.78
80	10.3.27.79/32	10.3.27.79 – 10.3.27.79	10.3.27.79
81	10.3.27.80/32	10.3.27.80 – 10.3.27.80	10.3.27.80
82	10.3.27.81/32	10.3.27.81 – 10.3.27.81	10.3.27.81
83	10.3.27.82/32	10.3.27.82 – 10.3.27.82	10.3.27.82
84	10.3.27.83/32	10.3.27.83 – 10.3.27.83	10.3.27.83
85	10.3.27.84/32	10.3.27.84 – 10.3.27.84	10.3.27.84
86	10.3.27.85/32	10.3.27.85 – 10.3.27.85	10.3.27.85
87	10.3.27.86/32	10.3.27.86 – 10.3.27.86	10.3.27.86
88	10.3.27.87/32	10.3.27.87 – 10.3.27.87	10.3.27.87
89	10.3.27.88/32	10.3.27.88 – 10.3.27.88	10.3.27.88
90	10.3.27.89/32	10.3.27.89 – 10.3.27.89	10.3.27.89
91	10.3.27.90/32	10.3.27.90 – 10.3.27.90	10.3.27.90
92	10.3.27.91/32	10.3.27.91 – 10.3.27.91	10.3.27.91
93	10.3.27.92/32	10.3.27.92 – 10.3.27.92	10.3.27.92
94	10.3.27.93/32	10.3.27.93 – 10.3.27.93	10.3.27.93
95	10.3.27.94/32	10.3.27.94 – 10.3.27.94	10.3.27.94
96	10.3.27.95/32	10.3.27.95 – 10.3.27.95	10.3.27.95
97	10.3.27.96/32	10.3.27.96 – 10.3.27.96	10.3.27.96
98	10.3.27.97/32	10.3.27.97 – 10.3.27.97	10.3.27.97
99	10.3.27.98/32	10.3.27.98 – 10.3.27.98	10.3.27.98
100	10.3.27.99/32	10.3.27.99 – 10.3.27.99	10.3.27.99
101	10.3.27.100/32	10.3.27.100 – 10.3.27.100	10.3.27.100
102	10.3.27.101/32	10.3.27.101 – 10.3.27.101	10.3.27.101
103	10.3.27.102/32	10.3.27.102 – 10.3.27.102	10.3.27.102
104	10.3.27.103/32	10.3.27.103 – 10.3.27.103	10.3.27.103
105	10.3.27.104/32	10.3.27.104 – 10.3.27.104	10.3.27.104
106	10.3.27.105/32	10.3.27.105 – 10.3.27.105	10.3.27.105
107	10.3.27.106/32	10.3.27.106 – 10.3.27.106	10.3.27.106
108	10.3.27.107/32	10.3.27.107 – 10.3.27.107	10.3.27.107
109	10.3.27.108/32	10.3.27.108 – 10.3.27.108	10.3.27.108
110	10.3.27.109/32	10.3.27.109 – 10.3.27.109	10.3.27.109
111	10.3.27.110/32	10.3.27.110 – 10.3.27.110	10.3.27.110
112	10.3.27.111/32	10.3.27.111 – 10.3.27.111	10.3.27.111
113	10.3.27.112/32	10.3.27.112 – 10.3.27.112	10.3.27.112
114	10.3.27.113/32	10.3.27.113 – 10.3.27.113	10.3.27.113
115	10.3.27.114/32	10.3.27.114 – 10.3.27.114	10.3.27.114
116	10.3.27.115/32	10.3.27.115 – 10.3.27.115	10.3.27.115
117	10.3.27.116/32	10.3.27.116 – 10.3.27.116	10.3.27.116
118	10.3.27.117/32	10.3.27.117 – 10.3.27.117	10.3.27.117
119	10.3.27.118/32	10.3.27.118 – 10.3.27.118	10.3.27.118
120	10.3.27.119/32	10.3.27.119 – 10.3.27.119	10.3.27.119
121	10.3.27.120/32	10.3.27.120 – 10.3.27.120	10.3.27.120
122	10.3.27.121/32	10.3.27.121 – 10.3.27.121	10.3.27.121
123	10.3.27.122/32	10.3.27.122 – 10.3.27.122	10.3.27.122
124	10.3.27.123/32	10.3.27.123 – 10.3.27.123	10.3.27.123
125	10.3.27.124/32	10.3.27.124 – 10.3.27.124	10.3.27.124
126	10.3.27.125/32	10.3.27.125 – 10.3.27.125	10.3.27.125
127	10.3.27.126/32	10.3.27.126 – 10.3.27.126	10.3.27.126
128	10.3.27.127/32	10.3.27.127 – 10.3.27.127	10.3.27.127

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 →