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)10.2.205.0/25

network10.2.205.0/25

broadcast10.2.205.127

first host10.2.205.1

last host10.2.205.126

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.2.205.0/25

address00001010.00000010.11001101.00000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000010.11001101.00000000

broadcast00001010.00000010.11001101.01111111

green = network part, grey = host part

hex0x0a02cd00

decimal167955712

reverse dns0.205.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:cd00

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.205.0/32	10.2.205.0 – 10.2.205.0	10.2.205.0
2	10.2.205.1/32	10.2.205.1 – 10.2.205.1	10.2.205.1
3	10.2.205.2/32	10.2.205.2 – 10.2.205.2	10.2.205.2
4	10.2.205.3/32	10.2.205.3 – 10.2.205.3	10.2.205.3
5	10.2.205.4/32	10.2.205.4 – 10.2.205.4	10.2.205.4
6	10.2.205.5/32	10.2.205.5 – 10.2.205.5	10.2.205.5
7	10.2.205.6/32	10.2.205.6 – 10.2.205.6	10.2.205.6
8	10.2.205.7/32	10.2.205.7 – 10.2.205.7	10.2.205.7
9	10.2.205.8/32	10.2.205.8 – 10.2.205.8	10.2.205.8
10	10.2.205.9/32	10.2.205.9 – 10.2.205.9	10.2.205.9
11	10.2.205.10/32	10.2.205.10 – 10.2.205.10	10.2.205.10
12	10.2.205.11/32	10.2.205.11 – 10.2.205.11	10.2.205.11
13	10.2.205.12/32	10.2.205.12 – 10.2.205.12	10.2.205.12
14	10.2.205.13/32	10.2.205.13 – 10.2.205.13	10.2.205.13
15	10.2.205.14/32	10.2.205.14 – 10.2.205.14	10.2.205.14
16	10.2.205.15/32	10.2.205.15 – 10.2.205.15	10.2.205.15
17	10.2.205.16/32	10.2.205.16 – 10.2.205.16	10.2.205.16
18	10.2.205.17/32	10.2.205.17 – 10.2.205.17	10.2.205.17
19	10.2.205.18/32	10.2.205.18 – 10.2.205.18	10.2.205.18
20	10.2.205.19/32	10.2.205.19 – 10.2.205.19	10.2.205.19
21	10.2.205.20/32	10.2.205.20 – 10.2.205.20	10.2.205.20
22	10.2.205.21/32	10.2.205.21 – 10.2.205.21	10.2.205.21
23	10.2.205.22/32	10.2.205.22 – 10.2.205.22	10.2.205.22
24	10.2.205.23/32	10.2.205.23 – 10.2.205.23	10.2.205.23
25	10.2.205.24/32	10.2.205.24 – 10.2.205.24	10.2.205.24
26	10.2.205.25/32	10.2.205.25 – 10.2.205.25	10.2.205.25
27	10.2.205.26/32	10.2.205.26 – 10.2.205.26	10.2.205.26
28	10.2.205.27/32	10.2.205.27 – 10.2.205.27	10.2.205.27
29	10.2.205.28/32	10.2.205.28 – 10.2.205.28	10.2.205.28
30	10.2.205.29/32	10.2.205.29 – 10.2.205.29	10.2.205.29
31	10.2.205.30/32	10.2.205.30 – 10.2.205.30	10.2.205.30
32	10.2.205.31/32	10.2.205.31 – 10.2.205.31	10.2.205.31
33	10.2.205.32/32	10.2.205.32 – 10.2.205.32	10.2.205.32
34	10.2.205.33/32	10.2.205.33 – 10.2.205.33	10.2.205.33
35	10.2.205.34/32	10.2.205.34 – 10.2.205.34	10.2.205.34
36	10.2.205.35/32	10.2.205.35 – 10.2.205.35	10.2.205.35
37	10.2.205.36/32	10.2.205.36 – 10.2.205.36	10.2.205.36
38	10.2.205.37/32	10.2.205.37 – 10.2.205.37	10.2.205.37
39	10.2.205.38/32	10.2.205.38 – 10.2.205.38	10.2.205.38
40	10.2.205.39/32	10.2.205.39 – 10.2.205.39	10.2.205.39
41	10.2.205.40/32	10.2.205.40 – 10.2.205.40	10.2.205.40
42	10.2.205.41/32	10.2.205.41 – 10.2.205.41	10.2.205.41
43	10.2.205.42/32	10.2.205.42 – 10.2.205.42	10.2.205.42
44	10.2.205.43/32	10.2.205.43 – 10.2.205.43	10.2.205.43
45	10.2.205.44/32	10.2.205.44 – 10.2.205.44	10.2.205.44
46	10.2.205.45/32	10.2.205.45 – 10.2.205.45	10.2.205.45
47	10.2.205.46/32	10.2.205.46 – 10.2.205.46	10.2.205.46
48	10.2.205.47/32	10.2.205.47 – 10.2.205.47	10.2.205.47
49	10.2.205.48/32	10.2.205.48 – 10.2.205.48	10.2.205.48
50	10.2.205.49/32	10.2.205.49 – 10.2.205.49	10.2.205.49
51	10.2.205.50/32	10.2.205.50 – 10.2.205.50	10.2.205.50
52	10.2.205.51/32	10.2.205.51 – 10.2.205.51	10.2.205.51
53	10.2.205.52/32	10.2.205.52 – 10.2.205.52	10.2.205.52
54	10.2.205.53/32	10.2.205.53 – 10.2.205.53	10.2.205.53
55	10.2.205.54/32	10.2.205.54 – 10.2.205.54	10.2.205.54
56	10.2.205.55/32	10.2.205.55 – 10.2.205.55	10.2.205.55
57	10.2.205.56/32	10.2.205.56 – 10.2.205.56	10.2.205.56
58	10.2.205.57/32	10.2.205.57 – 10.2.205.57	10.2.205.57
59	10.2.205.58/32	10.2.205.58 – 10.2.205.58	10.2.205.58
60	10.2.205.59/32	10.2.205.59 – 10.2.205.59	10.2.205.59
61	10.2.205.60/32	10.2.205.60 – 10.2.205.60	10.2.205.60
62	10.2.205.61/32	10.2.205.61 – 10.2.205.61	10.2.205.61
63	10.2.205.62/32	10.2.205.62 – 10.2.205.62	10.2.205.62
64	10.2.205.63/32	10.2.205.63 – 10.2.205.63	10.2.205.63
65	10.2.205.64/32	10.2.205.64 – 10.2.205.64	10.2.205.64
66	10.2.205.65/32	10.2.205.65 – 10.2.205.65	10.2.205.65
67	10.2.205.66/32	10.2.205.66 – 10.2.205.66	10.2.205.66
68	10.2.205.67/32	10.2.205.67 – 10.2.205.67	10.2.205.67
69	10.2.205.68/32	10.2.205.68 – 10.2.205.68	10.2.205.68
70	10.2.205.69/32	10.2.205.69 – 10.2.205.69	10.2.205.69
71	10.2.205.70/32	10.2.205.70 – 10.2.205.70	10.2.205.70
72	10.2.205.71/32	10.2.205.71 – 10.2.205.71	10.2.205.71
73	10.2.205.72/32	10.2.205.72 – 10.2.205.72	10.2.205.72
74	10.2.205.73/32	10.2.205.73 – 10.2.205.73	10.2.205.73
75	10.2.205.74/32	10.2.205.74 – 10.2.205.74	10.2.205.74
76	10.2.205.75/32	10.2.205.75 – 10.2.205.75	10.2.205.75
77	10.2.205.76/32	10.2.205.76 – 10.2.205.76	10.2.205.76
78	10.2.205.77/32	10.2.205.77 – 10.2.205.77	10.2.205.77
79	10.2.205.78/32	10.2.205.78 – 10.2.205.78	10.2.205.78
80	10.2.205.79/32	10.2.205.79 – 10.2.205.79	10.2.205.79
81	10.2.205.80/32	10.2.205.80 – 10.2.205.80	10.2.205.80
82	10.2.205.81/32	10.2.205.81 – 10.2.205.81	10.2.205.81
83	10.2.205.82/32	10.2.205.82 – 10.2.205.82	10.2.205.82
84	10.2.205.83/32	10.2.205.83 – 10.2.205.83	10.2.205.83
85	10.2.205.84/32	10.2.205.84 – 10.2.205.84	10.2.205.84
86	10.2.205.85/32	10.2.205.85 – 10.2.205.85	10.2.205.85
87	10.2.205.86/32	10.2.205.86 – 10.2.205.86	10.2.205.86
88	10.2.205.87/32	10.2.205.87 – 10.2.205.87	10.2.205.87
89	10.2.205.88/32	10.2.205.88 – 10.2.205.88	10.2.205.88
90	10.2.205.89/32	10.2.205.89 – 10.2.205.89	10.2.205.89
91	10.2.205.90/32	10.2.205.90 – 10.2.205.90	10.2.205.90
92	10.2.205.91/32	10.2.205.91 – 10.2.205.91	10.2.205.91
93	10.2.205.92/32	10.2.205.92 – 10.2.205.92	10.2.205.92
94	10.2.205.93/32	10.2.205.93 – 10.2.205.93	10.2.205.93
95	10.2.205.94/32	10.2.205.94 – 10.2.205.94	10.2.205.94
96	10.2.205.95/32	10.2.205.95 – 10.2.205.95	10.2.205.95
97	10.2.205.96/32	10.2.205.96 – 10.2.205.96	10.2.205.96
98	10.2.205.97/32	10.2.205.97 – 10.2.205.97	10.2.205.97
99	10.2.205.98/32	10.2.205.98 – 10.2.205.98	10.2.205.98
100	10.2.205.99/32	10.2.205.99 – 10.2.205.99	10.2.205.99
101	10.2.205.100/32	10.2.205.100 – 10.2.205.100	10.2.205.100
102	10.2.205.101/32	10.2.205.101 – 10.2.205.101	10.2.205.101
103	10.2.205.102/32	10.2.205.102 – 10.2.205.102	10.2.205.102
104	10.2.205.103/32	10.2.205.103 – 10.2.205.103	10.2.205.103
105	10.2.205.104/32	10.2.205.104 – 10.2.205.104	10.2.205.104
106	10.2.205.105/32	10.2.205.105 – 10.2.205.105	10.2.205.105
107	10.2.205.106/32	10.2.205.106 – 10.2.205.106	10.2.205.106
108	10.2.205.107/32	10.2.205.107 – 10.2.205.107	10.2.205.107
109	10.2.205.108/32	10.2.205.108 – 10.2.205.108	10.2.205.108
110	10.2.205.109/32	10.2.205.109 – 10.2.205.109	10.2.205.109
111	10.2.205.110/32	10.2.205.110 – 10.2.205.110	10.2.205.110
112	10.2.205.111/32	10.2.205.111 – 10.2.205.111	10.2.205.111
113	10.2.205.112/32	10.2.205.112 – 10.2.205.112	10.2.205.112
114	10.2.205.113/32	10.2.205.113 – 10.2.205.113	10.2.205.113
115	10.2.205.114/32	10.2.205.114 – 10.2.205.114	10.2.205.114
116	10.2.205.115/32	10.2.205.115 – 10.2.205.115	10.2.205.115
117	10.2.205.116/32	10.2.205.116 – 10.2.205.116	10.2.205.116
118	10.2.205.117/32	10.2.205.117 – 10.2.205.117	10.2.205.117
119	10.2.205.118/32	10.2.205.118 – 10.2.205.118	10.2.205.118
120	10.2.205.119/32	10.2.205.119 – 10.2.205.119	10.2.205.119
121	10.2.205.120/32	10.2.205.120 – 10.2.205.120	10.2.205.120
122	10.2.205.121/32	10.2.205.121 – 10.2.205.121	10.2.205.121
123	10.2.205.122/32	10.2.205.122 – 10.2.205.122	10.2.205.122
124	10.2.205.123/32	10.2.205.123 – 10.2.205.123	10.2.205.123
125	10.2.205.124/32	10.2.205.124 – 10.2.205.124	10.2.205.124
126	10.2.205.125/32	10.2.205.125 – 10.2.205.125	10.2.205.125
127	10.2.205.126/32	10.2.205.126 – 10.2.205.126	10.2.205.126
128	10.2.205.127/32	10.2.205.127 – 10.2.205.127	10.2.205.127

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 →