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)10.2.65.128/25

network10.2.65.128/25

broadcast10.2.65.255

first host10.2.65.129

last host10.2.65.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.2.65.128/25

address00001010.00000010.01000001.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000010.01000001.10000000

broadcast00001010.00000010.01000001.11111111

green = network part, grey = host part

hex0x0a024180

decimal167920000

reverse dns128.65.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:4180

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.65.128/32	10.2.65.128 – 10.2.65.128	10.2.65.128
2	10.2.65.129/32	10.2.65.129 – 10.2.65.129	10.2.65.129
3	10.2.65.130/32	10.2.65.130 – 10.2.65.130	10.2.65.130
4	10.2.65.131/32	10.2.65.131 – 10.2.65.131	10.2.65.131
5	10.2.65.132/32	10.2.65.132 – 10.2.65.132	10.2.65.132
6	10.2.65.133/32	10.2.65.133 – 10.2.65.133	10.2.65.133
7	10.2.65.134/32	10.2.65.134 – 10.2.65.134	10.2.65.134
8	10.2.65.135/32	10.2.65.135 – 10.2.65.135	10.2.65.135
9	10.2.65.136/32	10.2.65.136 – 10.2.65.136	10.2.65.136
10	10.2.65.137/32	10.2.65.137 – 10.2.65.137	10.2.65.137
11	10.2.65.138/32	10.2.65.138 – 10.2.65.138	10.2.65.138
12	10.2.65.139/32	10.2.65.139 – 10.2.65.139	10.2.65.139
13	10.2.65.140/32	10.2.65.140 – 10.2.65.140	10.2.65.140
14	10.2.65.141/32	10.2.65.141 – 10.2.65.141	10.2.65.141
15	10.2.65.142/32	10.2.65.142 – 10.2.65.142	10.2.65.142
16	10.2.65.143/32	10.2.65.143 – 10.2.65.143	10.2.65.143
17	10.2.65.144/32	10.2.65.144 – 10.2.65.144	10.2.65.144
18	10.2.65.145/32	10.2.65.145 – 10.2.65.145	10.2.65.145
19	10.2.65.146/32	10.2.65.146 – 10.2.65.146	10.2.65.146
20	10.2.65.147/32	10.2.65.147 – 10.2.65.147	10.2.65.147
21	10.2.65.148/32	10.2.65.148 – 10.2.65.148	10.2.65.148
22	10.2.65.149/32	10.2.65.149 – 10.2.65.149	10.2.65.149
23	10.2.65.150/32	10.2.65.150 – 10.2.65.150	10.2.65.150
24	10.2.65.151/32	10.2.65.151 – 10.2.65.151	10.2.65.151
25	10.2.65.152/32	10.2.65.152 – 10.2.65.152	10.2.65.152
26	10.2.65.153/32	10.2.65.153 – 10.2.65.153	10.2.65.153
27	10.2.65.154/32	10.2.65.154 – 10.2.65.154	10.2.65.154
28	10.2.65.155/32	10.2.65.155 – 10.2.65.155	10.2.65.155
29	10.2.65.156/32	10.2.65.156 – 10.2.65.156	10.2.65.156
30	10.2.65.157/32	10.2.65.157 – 10.2.65.157	10.2.65.157
31	10.2.65.158/32	10.2.65.158 – 10.2.65.158	10.2.65.158
32	10.2.65.159/32	10.2.65.159 – 10.2.65.159	10.2.65.159
33	10.2.65.160/32	10.2.65.160 – 10.2.65.160	10.2.65.160
34	10.2.65.161/32	10.2.65.161 – 10.2.65.161	10.2.65.161
35	10.2.65.162/32	10.2.65.162 – 10.2.65.162	10.2.65.162
36	10.2.65.163/32	10.2.65.163 – 10.2.65.163	10.2.65.163
37	10.2.65.164/32	10.2.65.164 – 10.2.65.164	10.2.65.164
38	10.2.65.165/32	10.2.65.165 – 10.2.65.165	10.2.65.165
39	10.2.65.166/32	10.2.65.166 – 10.2.65.166	10.2.65.166
40	10.2.65.167/32	10.2.65.167 – 10.2.65.167	10.2.65.167
41	10.2.65.168/32	10.2.65.168 – 10.2.65.168	10.2.65.168
42	10.2.65.169/32	10.2.65.169 – 10.2.65.169	10.2.65.169
43	10.2.65.170/32	10.2.65.170 – 10.2.65.170	10.2.65.170
44	10.2.65.171/32	10.2.65.171 – 10.2.65.171	10.2.65.171
45	10.2.65.172/32	10.2.65.172 – 10.2.65.172	10.2.65.172
46	10.2.65.173/32	10.2.65.173 – 10.2.65.173	10.2.65.173
47	10.2.65.174/32	10.2.65.174 – 10.2.65.174	10.2.65.174
48	10.2.65.175/32	10.2.65.175 – 10.2.65.175	10.2.65.175
49	10.2.65.176/32	10.2.65.176 – 10.2.65.176	10.2.65.176
50	10.2.65.177/32	10.2.65.177 – 10.2.65.177	10.2.65.177
51	10.2.65.178/32	10.2.65.178 – 10.2.65.178	10.2.65.178
52	10.2.65.179/32	10.2.65.179 – 10.2.65.179	10.2.65.179
53	10.2.65.180/32	10.2.65.180 – 10.2.65.180	10.2.65.180
54	10.2.65.181/32	10.2.65.181 – 10.2.65.181	10.2.65.181
55	10.2.65.182/32	10.2.65.182 – 10.2.65.182	10.2.65.182
56	10.2.65.183/32	10.2.65.183 – 10.2.65.183	10.2.65.183
57	10.2.65.184/32	10.2.65.184 – 10.2.65.184	10.2.65.184
58	10.2.65.185/32	10.2.65.185 – 10.2.65.185	10.2.65.185
59	10.2.65.186/32	10.2.65.186 – 10.2.65.186	10.2.65.186
60	10.2.65.187/32	10.2.65.187 – 10.2.65.187	10.2.65.187
61	10.2.65.188/32	10.2.65.188 – 10.2.65.188	10.2.65.188
62	10.2.65.189/32	10.2.65.189 – 10.2.65.189	10.2.65.189
63	10.2.65.190/32	10.2.65.190 – 10.2.65.190	10.2.65.190
64	10.2.65.191/32	10.2.65.191 – 10.2.65.191	10.2.65.191
65	10.2.65.192/32	10.2.65.192 – 10.2.65.192	10.2.65.192
66	10.2.65.193/32	10.2.65.193 – 10.2.65.193	10.2.65.193
67	10.2.65.194/32	10.2.65.194 – 10.2.65.194	10.2.65.194
68	10.2.65.195/32	10.2.65.195 – 10.2.65.195	10.2.65.195
69	10.2.65.196/32	10.2.65.196 – 10.2.65.196	10.2.65.196
70	10.2.65.197/32	10.2.65.197 – 10.2.65.197	10.2.65.197
71	10.2.65.198/32	10.2.65.198 – 10.2.65.198	10.2.65.198
72	10.2.65.199/32	10.2.65.199 – 10.2.65.199	10.2.65.199
73	10.2.65.200/32	10.2.65.200 – 10.2.65.200	10.2.65.200
74	10.2.65.201/32	10.2.65.201 – 10.2.65.201	10.2.65.201
75	10.2.65.202/32	10.2.65.202 – 10.2.65.202	10.2.65.202
76	10.2.65.203/32	10.2.65.203 – 10.2.65.203	10.2.65.203
77	10.2.65.204/32	10.2.65.204 – 10.2.65.204	10.2.65.204
78	10.2.65.205/32	10.2.65.205 – 10.2.65.205	10.2.65.205
79	10.2.65.206/32	10.2.65.206 – 10.2.65.206	10.2.65.206
80	10.2.65.207/32	10.2.65.207 – 10.2.65.207	10.2.65.207
81	10.2.65.208/32	10.2.65.208 – 10.2.65.208	10.2.65.208
82	10.2.65.209/32	10.2.65.209 – 10.2.65.209	10.2.65.209
83	10.2.65.210/32	10.2.65.210 – 10.2.65.210	10.2.65.210
84	10.2.65.211/32	10.2.65.211 – 10.2.65.211	10.2.65.211
85	10.2.65.212/32	10.2.65.212 – 10.2.65.212	10.2.65.212
86	10.2.65.213/32	10.2.65.213 – 10.2.65.213	10.2.65.213
87	10.2.65.214/32	10.2.65.214 – 10.2.65.214	10.2.65.214
88	10.2.65.215/32	10.2.65.215 – 10.2.65.215	10.2.65.215
89	10.2.65.216/32	10.2.65.216 – 10.2.65.216	10.2.65.216
90	10.2.65.217/32	10.2.65.217 – 10.2.65.217	10.2.65.217
91	10.2.65.218/32	10.2.65.218 – 10.2.65.218	10.2.65.218
92	10.2.65.219/32	10.2.65.219 – 10.2.65.219	10.2.65.219
93	10.2.65.220/32	10.2.65.220 – 10.2.65.220	10.2.65.220
94	10.2.65.221/32	10.2.65.221 – 10.2.65.221	10.2.65.221
95	10.2.65.222/32	10.2.65.222 – 10.2.65.222	10.2.65.222
96	10.2.65.223/32	10.2.65.223 – 10.2.65.223	10.2.65.223
97	10.2.65.224/32	10.2.65.224 – 10.2.65.224	10.2.65.224
98	10.2.65.225/32	10.2.65.225 – 10.2.65.225	10.2.65.225
99	10.2.65.226/32	10.2.65.226 – 10.2.65.226	10.2.65.226
100	10.2.65.227/32	10.2.65.227 – 10.2.65.227	10.2.65.227
101	10.2.65.228/32	10.2.65.228 – 10.2.65.228	10.2.65.228
102	10.2.65.229/32	10.2.65.229 – 10.2.65.229	10.2.65.229
103	10.2.65.230/32	10.2.65.230 – 10.2.65.230	10.2.65.230
104	10.2.65.231/32	10.2.65.231 – 10.2.65.231	10.2.65.231
105	10.2.65.232/32	10.2.65.232 – 10.2.65.232	10.2.65.232
106	10.2.65.233/32	10.2.65.233 – 10.2.65.233	10.2.65.233
107	10.2.65.234/32	10.2.65.234 – 10.2.65.234	10.2.65.234
108	10.2.65.235/32	10.2.65.235 – 10.2.65.235	10.2.65.235
109	10.2.65.236/32	10.2.65.236 – 10.2.65.236	10.2.65.236
110	10.2.65.237/32	10.2.65.237 – 10.2.65.237	10.2.65.237
111	10.2.65.238/32	10.2.65.238 – 10.2.65.238	10.2.65.238
112	10.2.65.239/32	10.2.65.239 – 10.2.65.239	10.2.65.239
113	10.2.65.240/32	10.2.65.240 – 10.2.65.240	10.2.65.240
114	10.2.65.241/32	10.2.65.241 – 10.2.65.241	10.2.65.241
115	10.2.65.242/32	10.2.65.242 – 10.2.65.242	10.2.65.242
116	10.2.65.243/32	10.2.65.243 – 10.2.65.243	10.2.65.243
117	10.2.65.244/32	10.2.65.244 – 10.2.65.244	10.2.65.244
118	10.2.65.245/32	10.2.65.245 – 10.2.65.245	10.2.65.245
119	10.2.65.246/32	10.2.65.246 – 10.2.65.246	10.2.65.246
120	10.2.65.247/32	10.2.65.247 – 10.2.65.247	10.2.65.247
121	10.2.65.248/32	10.2.65.248 – 10.2.65.248	10.2.65.248
122	10.2.65.249/32	10.2.65.249 – 10.2.65.249	10.2.65.249
123	10.2.65.250/32	10.2.65.250 – 10.2.65.250	10.2.65.250
124	10.2.65.251/32	10.2.65.251 – 10.2.65.251	10.2.65.251
125	10.2.65.252/32	10.2.65.252 – 10.2.65.252	10.2.65.252
126	10.2.65.253/32	10.2.65.253 – 10.2.65.253	10.2.65.253
127	10.2.65.254/32	10.2.65.254 – 10.2.65.254	10.2.65.254
128	10.2.65.255/32	10.2.65.255 – 10.2.65.255	10.2.65.255

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 /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 →