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)10.2.165.0/24

network10.2.165.0/24

broadcast10.2.165.255

first host10.2.165.1

last host10.2.165.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.2.165.0/24

address00001010.00000010.10100101.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.00000010.10100101.00000000

broadcast00001010.00000010.10100101.11111111

green = network part, grey = host part

hex0x0a02a500

decimal167945472

reverse dns0.165.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:a500

/24 split into /31 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.165.0/31	10.2.165.0 – 10.2.165.1	10.2.165.1
2	10.2.165.2/31	10.2.165.2 – 10.2.165.3	10.2.165.3
3	10.2.165.4/31	10.2.165.4 – 10.2.165.5	10.2.165.5
4	10.2.165.6/31	10.2.165.6 – 10.2.165.7	10.2.165.7
5	10.2.165.8/31	10.2.165.8 – 10.2.165.9	10.2.165.9
6	10.2.165.10/31	10.2.165.10 – 10.2.165.11	10.2.165.11
7	10.2.165.12/31	10.2.165.12 – 10.2.165.13	10.2.165.13
8	10.2.165.14/31	10.2.165.14 – 10.2.165.15	10.2.165.15
9	10.2.165.16/31	10.2.165.16 – 10.2.165.17	10.2.165.17
10	10.2.165.18/31	10.2.165.18 – 10.2.165.19	10.2.165.19
11	10.2.165.20/31	10.2.165.20 – 10.2.165.21	10.2.165.21
12	10.2.165.22/31	10.2.165.22 – 10.2.165.23	10.2.165.23
13	10.2.165.24/31	10.2.165.24 – 10.2.165.25	10.2.165.25
14	10.2.165.26/31	10.2.165.26 – 10.2.165.27	10.2.165.27
15	10.2.165.28/31	10.2.165.28 – 10.2.165.29	10.2.165.29
16	10.2.165.30/31	10.2.165.30 – 10.2.165.31	10.2.165.31
17	10.2.165.32/31	10.2.165.32 – 10.2.165.33	10.2.165.33
18	10.2.165.34/31	10.2.165.34 – 10.2.165.35	10.2.165.35
19	10.2.165.36/31	10.2.165.36 – 10.2.165.37	10.2.165.37
20	10.2.165.38/31	10.2.165.38 – 10.2.165.39	10.2.165.39
21	10.2.165.40/31	10.2.165.40 – 10.2.165.41	10.2.165.41
22	10.2.165.42/31	10.2.165.42 – 10.2.165.43	10.2.165.43
23	10.2.165.44/31	10.2.165.44 – 10.2.165.45	10.2.165.45
24	10.2.165.46/31	10.2.165.46 – 10.2.165.47	10.2.165.47
25	10.2.165.48/31	10.2.165.48 – 10.2.165.49	10.2.165.49
26	10.2.165.50/31	10.2.165.50 – 10.2.165.51	10.2.165.51
27	10.2.165.52/31	10.2.165.52 – 10.2.165.53	10.2.165.53
28	10.2.165.54/31	10.2.165.54 – 10.2.165.55	10.2.165.55
29	10.2.165.56/31	10.2.165.56 – 10.2.165.57	10.2.165.57
30	10.2.165.58/31	10.2.165.58 – 10.2.165.59	10.2.165.59
31	10.2.165.60/31	10.2.165.60 – 10.2.165.61	10.2.165.61
32	10.2.165.62/31	10.2.165.62 – 10.2.165.63	10.2.165.63
33	10.2.165.64/31	10.2.165.64 – 10.2.165.65	10.2.165.65
34	10.2.165.66/31	10.2.165.66 – 10.2.165.67	10.2.165.67
35	10.2.165.68/31	10.2.165.68 – 10.2.165.69	10.2.165.69
36	10.2.165.70/31	10.2.165.70 – 10.2.165.71	10.2.165.71
37	10.2.165.72/31	10.2.165.72 – 10.2.165.73	10.2.165.73
38	10.2.165.74/31	10.2.165.74 – 10.2.165.75	10.2.165.75
39	10.2.165.76/31	10.2.165.76 – 10.2.165.77	10.2.165.77
40	10.2.165.78/31	10.2.165.78 – 10.2.165.79	10.2.165.79
41	10.2.165.80/31	10.2.165.80 – 10.2.165.81	10.2.165.81
42	10.2.165.82/31	10.2.165.82 – 10.2.165.83	10.2.165.83
43	10.2.165.84/31	10.2.165.84 – 10.2.165.85	10.2.165.85
44	10.2.165.86/31	10.2.165.86 – 10.2.165.87	10.2.165.87
45	10.2.165.88/31	10.2.165.88 – 10.2.165.89	10.2.165.89
46	10.2.165.90/31	10.2.165.90 – 10.2.165.91	10.2.165.91
47	10.2.165.92/31	10.2.165.92 – 10.2.165.93	10.2.165.93
48	10.2.165.94/31	10.2.165.94 – 10.2.165.95	10.2.165.95
49	10.2.165.96/31	10.2.165.96 – 10.2.165.97	10.2.165.97
50	10.2.165.98/31	10.2.165.98 – 10.2.165.99	10.2.165.99
51	10.2.165.100/31	10.2.165.100 – 10.2.165.101	10.2.165.101
52	10.2.165.102/31	10.2.165.102 – 10.2.165.103	10.2.165.103
53	10.2.165.104/31	10.2.165.104 – 10.2.165.105	10.2.165.105
54	10.2.165.106/31	10.2.165.106 – 10.2.165.107	10.2.165.107
55	10.2.165.108/31	10.2.165.108 – 10.2.165.109	10.2.165.109
56	10.2.165.110/31	10.2.165.110 – 10.2.165.111	10.2.165.111
57	10.2.165.112/31	10.2.165.112 – 10.2.165.113	10.2.165.113
58	10.2.165.114/31	10.2.165.114 – 10.2.165.115	10.2.165.115
59	10.2.165.116/31	10.2.165.116 – 10.2.165.117	10.2.165.117
60	10.2.165.118/31	10.2.165.118 – 10.2.165.119	10.2.165.119
61	10.2.165.120/31	10.2.165.120 – 10.2.165.121	10.2.165.121
62	10.2.165.122/31	10.2.165.122 – 10.2.165.123	10.2.165.123
63	10.2.165.124/31	10.2.165.124 – 10.2.165.125	10.2.165.125
64	10.2.165.126/31	10.2.165.126 – 10.2.165.127	10.2.165.127
65	10.2.165.128/31	10.2.165.128 – 10.2.165.129	10.2.165.129
66	10.2.165.130/31	10.2.165.130 – 10.2.165.131	10.2.165.131
67	10.2.165.132/31	10.2.165.132 – 10.2.165.133	10.2.165.133
68	10.2.165.134/31	10.2.165.134 – 10.2.165.135	10.2.165.135
69	10.2.165.136/31	10.2.165.136 – 10.2.165.137	10.2.165.137
70	10.2.165.138/31	10.2.165.138 – 10.2.165.139	10.2.165.139
71	10.2.165.140/31	10.2.165.140 – 10.2.165.141	10.2.165.141
72	10.2.165.142/31	10.2.165.142 – 10.2.165.143	10.2.165.143
73	10.2.165.144/31	10.2.165.144 – 10.2.165.145	10.2.165.145
74	10.2.165.146/31	10.2.165.146 – 10.2.165.147	10.2.165.147
75	10.2.165.148/31	10.2.165.148 – 10.2.165.149	10.2.165.149
76	10.2.165.150/31	10.2.165.150 – 10.2.165.151	10.2.165.151
77	10.2.165.152/31	10.2.165.152 – 10.2.165.153	10.2.165.153
78	10.2.165.154/31	10.2.165.154 – 10.2.165.155	10.2.165.155
79	10.2.165.156/31	10.2.165.156 – 10.2.165.157	10.2.165.157
80	10.2.165.158/31	10.2.165.158 – 10.2.165.159	10.2.165.159
81	10.2.165.160/31	10.2.165.160 – 10.2.165.161	10.2.165.161
82	10.2.165.162/31	10.2.165.162 – 10.2.165.163	10.2.165.163
83	10.2.165.164/31	10.2.165.164 – 10.2.165.165	10.2.165.165
84	10.2.165.166/31	10.2.165.166 – 10.2.165.167	10.2.165.167
85	10.2.165.168/31	10.2.165.168 – 10.2.165.169	10.2.165.169
86	10.2.165.170/31	10.2.165.170 – 10.2.165.171	10.2.165.171
87	10.2.165.172/31	10.2.165.172 – 10.2.165.173	10.2.165.173
88	10.2.165.174/31	10.2.165.174 – 10.2.165.175	10.2.165.175
89	10.2.165.176/31	10.2.165.176 – 10.2.165.177	10.2.165.177
90	10.2.165.178/31	10.2.165.178 – 10.2.165.179	10.2.165.179
91	10.2.165.180/31	10.2.165.180 – 10.2.165.181	10.2.165.181
92	10.2.165.182/31	10.2.165.182 – 10.2.165.183	10.2.165.183
93	10.2.165.184/31	10.2.165.184 – 10.2.165.185	10.2.165.185
94	10.2.165.186/31	10.2.165.186 – 10.2.165.187	10.2.165.187
95	10.2.165.188/31	10.2.165.188 – 10.2.165.189	10.2.165.189
96	10.2.165.190/31	10.2.165.190 – 10.2.165.191	10.2.165.191
97	10.2.165.192/31	10.2.165.192 – 10.2.165.193	10.2.165.193
98	10.2.165.194/31	10.2.165.194 – 10.2.165.195	10.2.165.195
99	10.2.165.196/31	10.2.165.196 – 10.2.165.197	10.2.165.197
100	10.2.165.198/31	10.2.165.198 – 10.2.165.199	10.2.165.199
101	10.2.165.200/31	10.2.165.200 – 10.2.165.201	10.2.165.201
102	10.2.165.202/31	10.2.165.202 – 10.2.165.203	10.2.165.203
103	10.2.165.204/31	10.2.165.204 – 10.2.165.205	10.2.165.205
104	10.2.165.206/31	10.2.165.206 – 10.2.165.207	10.2.165.207
105	10.2.165.208/31	10.2.165.208 – 10.2.165.209	10.2.165.209
106	10.2.165.210/31	10.2.165.210 – 10.2.165.211	10.2.165.211
107	10.2.165.212/31	10.2.165.212 – 10.2.165.213	10.2.165.213
108	10.2.165.214/31	10.2.165.214 – 10.2.165.215	10.2.165.215
109	10.2.165.216/31	10.2.165.216 – 10.2.165.217	10.2.165.217
110	10.2.165.218/31	10.2.165.218 – 10.2.165.219	10.2.165.219
111	10.2.165.220/31	10.2.165.220 – 10.2.165.221	10.2.165.221
112	10.2.165.222/31	10.2.165.222 – 10.2.165.223	10.2.165.223
113	10.2.165.224/31	10.2.165.224 – 10.2.165.225	10.2.165.225
114	10.2.165.226/31	10.2.165.226 – 10.2.165.227	10.2.165.227
115	10.2.165.228/31	10.2.165.228 – 10.2.165.229	10.2.165.229
116	10.2.165.230/31	10.2.165.230 – 10.2.165.231	10.2.165.231
117	10.2.165.232/31	10.2.165.232 – 10.2.165.233	10.2.165.233
118	10.2.165.234/31	10.2.165.234 – 10.2.165.235	10.2.165.235
119	10.2.165.236/31	10.2.165.236 – 10.2.165.237	10.2.165.237
120	10.2.165.238/31	10.2.165.238 – 10.2.165.239	10.2.165.239
121	10.2.165.240/31	10.2.165.240 – 10.2.165.241	10.2.165.241
122	10.2.165.242/31	10.2.165.242 – 10.2.165.243	10.2.165.243
123	10.2.165.244/31	10.2.165.244 – 10.2.165.245	10.2.165.245
124	10.2.165.246/31	10.2.165.246 – 10.2.165.247	10.2.165.247
125	10.2.165.248/31	10.2.165.248 – 10.2.165.249	10.2.165.249
126	10.2.165.250/31	10.2.165.250 – 10.2.165.251	10.2.165.251
127	10.2.165.252/31	10.2.165.252 – 10.2.165.253	10.2.165.253
128	10.2.165.254/31	10.2.165.254 – 10.2.165.255	10.2.165.255

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 /24
/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	1
/25	255.255.255.128	128	126	2 split →
/26	255.255.255.192	64	62	4 split →
/27	255.255.255.224	32	30	8 split →
/28	255.255.255.240	16	14	16 split →
/29	255.255.255.248	8	6	32 split →
/30	255.255.255.252	4	2	64 split →
/31	255.255.255.254	2	2	128 split →
/32	255.255.255.255	1	1	256 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 →