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)10.3.64.128/25

network10.3.64.128/25

broadcast10.3.64.255

first host10.3.64.129

last host10.3.64.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.3.64.128/25

address00001010.00000011.01000000.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000011.01000000.10000000

broadcast00001010.00000011.01000000.11111111

green = network part, grey = host part

hex0x0a034080

decimal167985280

reverse dns128.64.3.10.in-addr.arpa

ipv4-mapped::ffff:a03:4080

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.3.64.128/32	10.3.64.128 – 10.3.64.128	10.3.64.128
2	10.3.64.129/32	10.3.64.129 – 10.3.64.129	10.3.64.129
3	10.3.64.130/32	10.3.64.130 – 10.3.64.130	10.3.64.130
4	10.3.64.131/32	10.3.64.131 – 10.3.64.131	10.3.64.131
5	10.3.64.132/32	10.3.64.132 – 10.3.64.132	10.3.64.132
6	10.3.64.133/32	10.3.64.133 – 10.3.64.133	10.3.64.133
7	10.3.64.134/32	10.3.64.134 – 10.3.64.134	10.3.64.134
8	10.3.64.135/32	10.3.64.135 – 10.3.64.135	10.3.64.135
9	10.3.64.136/32	10.3.64.136 – 10.3.64.136	10.3.64.136
10	10.3.64.137/32	10.3.64.137 – 10.3.64.137	10.3.64.137
11	10.3.64.138/32	10.3.64.138 – 10.3.64.138	10.3.64.138
12	10.3.64.139/32	10.3.64.139 – 10.3.64.139	10.3.64.139
13	10.3.64.140/32	10.3.64.140 – 10.3.64.140	10.3.64.140
14	10.3.64.141/32	10.3.64.141 – 10.3.64.141	10.3.64.141
15	10.3.64.142/32	10.3.64.142 – 10.3.64.142	10.3.64.142
16	10.3.64.143/32	10.3.64.143 – 10.3.64.143	10.3.64.143
17	10.3.64.144/32	10.3.64.144 – 10.3.64.144	10.3.64.144
18	10.3.64.145/32	10.3.64.145 – 10.3.64.145	10.3.64.145
19	10.3.64.146/32	10.3.64.146 – 10.3.64.146	10.3.64.146
20	10.3.64.147/32	10.3.64.147 – 10.3.64.147	10.3.64.147
21	10.3.64.148/32	10.3.64.148 – 10.3.64.148	10.3.64.148
22	10.3.64.149/32	10.3.64.149 – 10.3.64.149	10.3.64.149
23	10.3.64.150/32	10.3.64.150 – 10.3.64.150	10.3.64.150
24	10.3.64.151/32	10.3.64.151 – 10.3.64.151	10.3.64.151
25	10.3.64.152/32	10.3.64.152 – 10.3.64.152	10.3.64.152
26	10.3.64.153/32	10.3.64.153 – 10.3.64.153	10.3.64.153
27	10.3.64.154/32	10.3.64.154 – 10.3.64.154	10.3.64.154
28	10.3.64.155/32	10.3.64.155 – 10.3.64.155	10.3.64.155
29	10.3.64.156/32	10.3.64.156 – 10.3.64.156	10.3.64.156
30	10.3.64.157/32	10.3.64.157 – 10.3.64.157	10.3.64.157
31	10.3.64.158/32	10.3.64.158 – 10.3.64.158	10.3.64.158
32	10.3.64.159/32	10.3.64.159 – 10.3.64.159	10.3.64.159
33	10.3.64.160/32	10.3.64.160 – 10.3.64.160	10.3.64.160
34	10.3.64.161/32	10.3.64.161 – 10.3.64.161	10.3.64.161
35	10.3.64.162/32	10.3.64.162 – 10.3.64.162	10.3.64.162
36	10.3.64.163/32	10.3.64.163 – 10.3.64.163	10.3.64.163
37	10.3.64.164/32	10.3.64.164 – 10.3.64.164	10.3.64.164
38	10.3.64.165/32	10.3.64.165 – 10.3.64.165	10.3.64.165
39	10.3.64.166/32	10.3.64.166 – 10.3.64.166	10.3.64.166
40	10.3.64.167/32	10.3.64.167 – 10.3.64.167	10.3.64.167
41	10.3.64.168/32	10.3.64.168 – 10.3.64.168	10.3.64.168
42	10.3.64.169/32	10.3.64.169 – 10.3.64.169	10.3.64.169
43	10.3.64.170/32	10.3.64.170 – 10.3.64.170	10.3.64.170
44	10.3.64.171/32	10.3.64.171 – 10.3.64.171	10.3.64.171
45	10.3.64.172/32	10.3.64.172 – 10.3.64.172	10.3.64.172
46	10.3.64.173/32	10.3.64.173 – 10.3.64.173	10.3.64.173
47	10.3.64.174/32	10.3.64.174 – 10.3.64.174	10.3.64.174
48	10.3.64.175/32	10.3.64.175 – 10.3.64.175	10.3.64.175
49	10.3.64.176/32	10.3.64.176 – 10.3.64.176	10.3.64.176
50	10.3.64.177/32	10.3.64.177 – 10.3.64.177	10.3.64.177
51	10.3.64.178/32	10.3.64.178 – 10.3.64.178	10.3.64.178
52	10.3.64.179/32	10.3.64.179 – 10.3.64.179	10.3.64.179
53	10.3.64.180/32	10.3.64.180 – 10.3.64.180	10.3.64.180
54	10.3.64.181/32	10.3.64.181 – 10.3.64.181	10.3.64.181
55	10.3.64.182/32	10.3.64.182 – 10.3.64.182	10.3.64.182
56	10.3.64.183/32	10.3.64.183 – 10.3.64.183	10.3.64.183
57	10.3.64.184/32	10.3.64.184 – 10.3.64.184	10.3.64.184
58	10.3.64.185/32	10.3.64.185 – 10.3.64.185	10.3.64.185
59	10.3.64.186/32	10.3.64.186 – 10.3.64.186	10.3.64.186
60	10.3.64.187/32	10.3.64.187 – 10.3.64.187	10.3.64.187
61	10.3.64.188/32	10.3.64.188 – 10.3.64.188	10.3.64.188
62	10.3.64.189/32	10.3.64.189 – 10.3.64.189	10.3.64.189
63	10.3.64.190/32	10.3.64.190 – 10.3.64.190	10.3.64.190
64	10.3.64.191/32	10.3.64.191 – 10.3.64.191	10.3.64.191
65	10.3.64.192/32	10.3.64.192 – 10.3.64.192	10.3.64.192
66	10.3.64.193/32	10.3.64.193 – 10.3.64.193	10.3.64.193
67	10.3.64.194/32	10.3.64.194 – 10.3.64.194	10.3.64.194
68	10.3.64.195/32	10.3.64.195 – 10.3.64.195	10.3.64.195
69	10.3.64.196/32	10.3.64.196 – 10.3.64.196	10.3.64.196
70	10.3.64.197/32	10.3.64.197 – 10.3.64.197	10.3.64.197
71	10.3.64.198/32	10.3.64.198 – 10.3.64.198	10.3.64.198
72	10.3.64.199/32	10.3.64.199 – 10.3.64.199	10.3.64.199
73	10.3.64.200/32	10.3.64.200 – 10.3.64.200	10.3.64.200
74	10.3.64.201/32	10.3.64.201 – 10.3.64.201	10.3.64.201
75	10.3.64.202/32	10.3.64.202 – 10.3.64.202	10.3.64.202
76	10.3.64.203/32	10.3.64.203 – 10.3.64.203	10.3.64.203
77	10.3.64.204/32	10.3.64.204 – 10.3.64.204	10.3.64.204
78	10.3.64.205/32	10.3.64.205 – 10.3.64.205	10.3.64.205
79	10.3.64.206/32	10.3.64.206 – 10.3.64.206	10.3.64.206
80	10.3.64.207/32	10.3.64.207 – 10.3.64.207	10.3.64.207
81	10.3.64.208/32	10.3.64.208 – 10.3.64.208	10.3.64.208
82	10.3.64.209/32	10.3.64.209 – 10.3.64.209	10.3.64.209
83	10.3.64.210/32	10.3.64.210 – 10.3.64.210	10.3.64.210
84	10.3.64.211/32	10.3.64.211 – 10.3.64.211	10.3.64.211
85	10.3.64.212/32	10.3.64.212 – 10.3.64.212	10.3.64.212
86	10.3.64.213/32	10.3.64.213 – 10.3.64.213	10.3.64.213
87	10.3.64.214/32	10.3.64.214 – 10.3.64.214	10.3.64.214
88	10.3.64.215/32	10.3.64.215 – 10.3.64.215	10.3.64.215
89	10.3.64.216/32	10.3.64.216 – 10.3.64.216	10.3.64.216
90	10.3.64.217/32	10.3.64.217 – 10.3.64.217	10.3.64.217
91	10.3.64.218/32	10.3.64.218 – 10.3.64.218	10.3.64.218
92	10.3.64.219/32	10.3.64.219 – 10.3.64.219	10.3.64.219
93	10.3.64.220/32	10.3.64.220 – 10.3.64.220	10.3.64.220
94	10.3.64.221/32	10.3.64.221 – 10.3.64.221	10.3.64.221
95	10.3.64.222/32	10.3.64.222 – 10.3.64.222	10.3.64.222
96	10.3.64.223/32	10.3.64.223 – 10.3.64.223	10.3.64.223
97	10.3.64.224/32	10.3.64.224 – 10.3.64.224	10.3.64.224
98	10.3.64.225/32	10.3.64.225 – 10.3.64.225	10.3.64.225
99	10.3.64.226/32	10.3.64.226 – 10.3.64.226	10.3.64.226
100	10.3.64.227/32	10.3.64.227 – 10.3.64.227	10.3.64.227
101	10.3.64.228/32	10.3.64.228 – 10.3.64.228	10.3.64.228
102	10.3.64.229/32	10.3.64.229 – 10.3.64.229	10.3.64.229
103	10.3.64.230/32	10.3.64.230 – 10.3.64.230	10.3.64.230
104	10.3.64.231/32	10.3.64.231 – 10.3.64.231	10.3.64.231
105	10.3.64.232/32	10.3.64.232 – 10.3.64.232	10.3.64.232
106	10.3.64.233/32	10.3.64.233 – 10.3.64.233	10.3.64.233
107	10.3.64.234/32	10.3.64.234 – 10.3.64.234	10.3.64.234
108	10.3.64.235/32	10.3.64.235 – 10.3.64.235	10.3.64.235
109	10.3.64.236/32	10.3.64.236 – 10.3.64.236	10.3.64.236
110	10.3.64.237/32	10.3.64.237 – 10.3.64.237	10.3.64.237
111	10.3.64.238/32	10.3.64.238 – 10.3.64.238	10.3.64.238
112	10.3.64.239/32	10.3.64.239 – 10.3.64.239	10.3.64.239
113	10.3.64.240/32	10.3.64.240 – 10.3.64.240	10.3.64.240
114	10.3.64.241/32	10.3.64.241 – 10.3.64.241	10.3.64.241
115	10.3.64.242/32	10.3.64.242 – 10.3.64.242	10.3.64.242
116	10.3.64.243/32	10.3.64.243 – 10.3.64.243	10.3.64.243
117	10.3.64.244/32	10.3.64.244 – 10.3.64.244	10.3.64.244
118	10.3.64.245/32	10.3.64.245 – 10.3.64.245	10.3.64.245
119	10.3.64.246/32	10.3.64.246 – 10.3.64.246	10.3.64.246
120	10.3.64.247/32	10.3.64.247 – 10.3.64.247	10.3.64.247
121	10.3.64.248/32	10.3.64.248 – 10.3.64.248	10.3.64.248
122	10.3.64.249/32	10.3.64.249 – 10.3.64.249	10.3.64.249
123	10.3.64.250/32	10.3.64.250 – 10.3.64.250	10.3.64.250
124	10.3.64.251/32	10.3.64.251 – 10.3.64.251	10.3.64.251
125	10.3.64.252/32	10.3.64.252 – 10.3.64.252	10.3.64.252
126	10.3.64.253/32	10.3.64.253 – 10.3.64.253	10.3.64.253
127	10.3.64.254/32	10.3.64.254 – 10.3.64.254	10.3.64.254
128	10.3.64.255/32	10.3.64.255 – 10.3.64.255	10.3.64.255

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 →