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)10.4.71.128/25

network10.4.71.128/25

broadcast10.4.71.255

first host10.4.71.129

last host10.4.71.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.4.71.128/25

address00001010.00000100.01000111.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000100.01000111.10000000

broadcast00001010.00000100.01000111.11111111

green = network part, grey = host part

hex0x0a044780

decimal168052608

reverse dns128.71.4.10.in-addr.arpa

ipv4-mapped::ffff:a04:4780

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.4.71.128/32	10.4.71.128 – 10.4.71.128	10.4.71.128
2	10.4.71.129/32	10.4.71.129 – 10.4.71.129	10.4.71.129
3	10.4.71.130/32	10.4.71.130 – 10.4.71.130	10.4.71.130
4	10.4.71.131/32	10.4.71.131 – 10.4.71.131	10.4.71.131
5	10.4.71.132/32	10.4.71.132 – 10.4.71.132	10.4.71.132
6	10.4.71.133/32	10.4.71.133 – 10.4.71.133	10.4.71.133
7	10.4.71.134/32	10.4.71.134 – 10.4.71.134	10.4.71.134
8	10.4.71.135/32	10.4.71.135 – 10.4.71.135	10.4.71.135
9	10.4.71.136/32	10.4.71.136 – 10.4.71.136	10.4.71.136
10	10.4.71.137/32	10.4.71.137 – 10.4.71.137	10.4.71.137
11	10.4.71.138/32	10.4.71.138 – 10.4.71.138	10.4.71.138
12	10.4.71.139/32	10.4.71.139 – 10.4.71.139	10.4.71.139
13	10.4.71.140/32	10.4.71.140 – 10.4.71.140	10.4.71.140
14	10.4.71.141/32	10.4.71.141 – 10.4.71.141	10.4.71.141
15	10.4.71.142/32	10.4.71.142 – 10.4.71.142	10.4.71.142
16	10.4.71.143/32	10.4.71.143 – 10.4.71.143	10.4.71.143
17	10.4.71.144/32	10.4.71.144 – 10.4.71.144	10.4.71.144
18	10.4.71.145/32	10.4.71.145 – 10.4.71.145	10.4.71.145
19	10.4.71.146/32	10.4.71.146 – 10.4.71.146	10.4.71.146
20	10.4.71.147/32	10.4.71.147 – 10.4.71.147	10.4.71.147
21	10.4.71.148/32	10.4.71.148 – 10.4.71.148	10.4.71.148
22	10.4.71.149/32	10.4.71.149 – 10.4.71.149	10.4.71.149
23	10.4.71.150/32	10.4.71.150 – 10.4.71.150	10.4.71.150
24	10.4.71.151/32	10.4.71.151 – 10.4.71.151	10.4.71.151
25	10.4.71.152/32	10.4.71.152 – 10.4.71.152	10.4.71.152
26	10.4.71.153/32	10.4.71.153 – 10.4.71.153	10.4.71.153
27	10.4.71.154/32	10.4.71.154 – 10.4.71.154	10.4.71.154
28	10.4.71.155/32	10.4.71.155 – 10.4.71.155	10.4.71.155
29	10.4.71.156/32	10.4.71.156 – 10.4.71.156	10.4.71.156
30	10.4.71.157/32	10.4.71.157 – 10.4.71.157	10.4.71.157
31	10.4.71.158/32	10.4.71.158 – 10.4.71.158	10.4.71.158
32	10.4.71.159/32	10.4.71.159 – 10.4.71.159	10.4.71.159
33	10.4.71.160/32	10.4.71.160 – 10.4.71.160	10.4.71.160
34	10.4.71.161/32	10.4.71.161 – 10.4.71.161	10.4.71.161
35	10.4.71.162/32	10.4.71.162 – 10.4.71.162	10.4.71.162
36	10.4.71.163/32	10.4.71.163 – 10.4.71.163	10.4.71.163
37	10.4.71.164/32	10.4.71.164 – 10.4.71.164	10.4.71.164
38	10.4.71.165/32	10.4.71.165 – 10.4.71.165	10.4.71.165
39	10.4.71.166/32	10.4.71.166 – 10.4.71.166	10.4.71.166
40	10.4.71.167/32	10.4.71.167 – 10.4.71.167	10.4.71.167
41	10.4.71.168/32	10.4.71.168 – 10.4.71.168	10.4.71.168
42	10.4.71.169/32	10.4.71.169 – 10.4.71.169	10.4.71.169
43	10.4.71.170/32	10.4.71.170 – 10.4.71.170	10.4.71.170
44	10.4.71.171/32	10.4.71.171 – 10.4.71.171	10.4.71.171
45	10.4.71.172/32	10.4.71.172 – 10.4.71.172	10.4.71.172
46	10.4.71.173/32	10.4.71.173 – 10.4.71.173	10.4.71.173
47	10.4.71.174/32	10.4.71.174 – 10.4.71.174	10.4.71.174
48	10.4.71.175/32	10.4.71.175 – 10.4.71.175	10.4.71.175
49	10.4.71.176/32	10.4.71.176 – 10.4.71.176	10.4.71.176
50	10.4.71.177/32	10.4.71.177 – 10.4.71.177	10.4.71.177
51	10.4.71.178/32	10.4.71.178 – 10.4.71.178	10.4.71.178
52	10.4.71.179/32	10.4.71.179 – 10.4.71.179	10.4.71.179
53	10.4.71.180/32	10.4.71.180 – 10.4.71.180	10.4.71.180
54	10.4.71.181/32	10.4.71.181 – 10.4.71.181	10.4.71.181
55	10.4.71.182/32	10.4.71.182 – 10.4.71.182	10.4.71.182
56	10.4.71.183/32	10.4.71.183 – 10.4.71.183	10.4.71.183
57	10.4.71.184/32	10.4.71.184 – 10.4.71.184	10.4.71.184
58	10.4.71.185/32	10.4.71.185 – 10.4.71.185	10.4.71.185
59	10.4.71.186/32	10.4.71.186 – 10.4.71.186	10.4.71.186
60	10.4.71.187/32	10.4.71.187 – 10.4.71.187	10.4.71.187
61	10.4.71.188/32	10.4.71.188 – 10.4.71.188	10.4.71.188
62	10.4.71.189/32	10.4.71.189 – 10.4.71.189	10.4.71.189
63	10.4.71.190/32	10.4.71.190 – 10.4.71.190	10.4.71.190
64	10.4.71.191/32	10.4.71.191 – 10.4.71.191	10.4.71.191
65	10.4.71.192/32	10.4.71.192 – 10.4.71.192	10.4.71.192
66	10.4.71.193/32	10.4.71.193 – 10.4.71.193	10.4.71.193
67	10.4.71.194/32	10.4.71.194 – 10.4.71.194	10.4.71.194
68	10.4.71.195/32	10.4.71.195 – 10.4.71.195	10.4.71.195
69	10.4.71.196/32	10.4.71.196 – 10.4.71.196	10.4.71.196
70	10.4.71.197/32	10.4.71.197 – 10.4.71.197	10.4.71.197
71	10.4.71.198/32	10.4.71.198 – 10.4.71.198	10.4.71.198
72	10.4.71.199/32	10.4.71.199 – 10.4.71.199	10.4.71.199
73	10.4.71.200/32	10.4.71.200 – 10.4.71.200	10.4.71.200
74	10.4.71.201/32	10.4.71.201 – 10.4.71.201	10.4.71.201
75	10.4.71.202/32	10.4.71.202 – 10.4.71.202	10.4.71.202
76	10.4.71.203/32	10.4.71.203 – 10.4.71.203	10.4.71.203
77	10.4.71.204/32	10.4.71.204 – 10.4.71.204	10.4.71.204
78	10.4.71.205/32	10.4.71.205 – 10.4.71.205	10.4.71.205
79	10.4.71.206/32	10.4.71.206 – 10.4.71.206	10.4.71.206
80	10.4.71.207/32	10.4.71.207 – 10.4.71.207	10.4.71.207
81	10.4.71.208/32	10.4.71.208 – 10.4.71.208	10.4.71.208
82	10.4.71.209/32	10.4.71.209 – 10.4.71.209	10.4.71.209
83	10.4.71.210/32	10.4.71.210 – 10.4.71.210	10.4.71.210
84	10.4.71.211/32	10.4.71.211 – 10.4.71.211	10.4.71.211
85	10.4.71.212/32	10.4.71.212 – 10.4.71.212	10.4.71.212
86	10.4.71.213/32	10.4.71.213 – 10.4.71.213	10.4.71.213
87	10.4.71.214/32	10.4.71.214 – 10.4.71.214	10.4.71.214
88	10.4.71.215/32	10.4.71.215 – 10.4.71.215	10.4.71.215
89	10.4.71.216/32	10.4.71.216 – 10.4.71.216	10.4.71.216
90	10.4.71.217/32	10.4.71.217 – 10.4.71.217	10.4.71.217
91	10.4.71.218/32	10.4.71.218 – 10.4.71.218	10.4.71.218
92	10.4.71.219/32	10.4.71.219 – 10.4.71.219	10.4.71.219
93	10.4.71.220/32	10.4.71.220 – 10.4.71.220	10.4.71.220
94	10.4.71.221/32	10.4.71.221 – 10.4.71.221	10.4.71.221
95	10.4.71.222/32	10.4.71.222 – 10.4.71.222	10.4.71.222
96	10.4.71.223/32	10.4.71.223 – 10.4.71.223	10.4.71.223
97	10.4.71.224/32	10.4.71.224 – 10.4.71.224	10.4.71.224
98	10.4.71.225/32	10.4.71.225 – 10.4.71.225	10.4.71.225
99	10.4.71.226/32	10.4.71.226 – 10.4.71.226	10.4.71.226
100	10.4.71.227/32	10.4.71.227 – 10.4.71.227	10.4.71.227
101	10.4.71.228/32	10.4.71.228 – 10.4.71.228	10.4.71.228
102	10.4.71.229/32	10.4.71.229 – 10.4.71.229	10.4.71.229
103	10.4.71.230/32	10.4.71.230 – 10.4.71.230	10.4.71.230
104	10.4.71.231/32	10.4.71.231 – 10.4.71.231	10.4.71.231
105	10.4.71.232/32	10.4.71.232 – 10.4.71.232	10.4.71.232
106	10.4.71.233/32	10.4.71.233 – 10.4.71.233	10.4.71.233
107	10.4.71.234/32	10.4.71.234 – 10.4.71.234	10.4.71.234
108	10.4.71.235/32	10.4.71.235 – 10.4.71.235	10.4.71.235
109	10.4.71.236/32	10.4.71.236 – 10.4.71.236	10.4.71.236
110	10.4.71.237/32	10.4.71.237 – 10.4.71.237	10.4.71.237
111	10.4.71.238/32	10.4.71.238 – 10.4.71.238	10.4.71.238
112	10.4.71.239/32	10.4.71.239 – 10.4.71.239	10.4.71.239
113	10.4.71.240/32	10.4.71.240 – 10.4.71.240	10.4.71.240
114	10.4.71.241/32	10.4.71.241 – 10.4.71.241	10.4.71.241
115	10.4.71.242/32	10.4.71.242 – 10.4.71.242	10.4.71.242
116	10.4.71.243/32	10.4.71.243 – 10.4.71.243	10.4.71.243
117	10.4.71.244/32	10.4.71.244 – 10.4.71.244	10.4.71.244
118	10.4.71.245/32	10.4.71.245 – 10.4.71.245	10.4.71.245
119	10.4.71.246/32	10.4.71.246 – 10.4.71.246	10.4.71.246
120	10.4.71.247/32	10.4.71.247 – 10.4.71.247	10.4.71.247
121	10.4.71.248/32	10.4.71.248 – 10.4.71.248	10.4.71.248
122	10.4.71.249/32	10.4.71.249 – 10.4.71.249	10.4.71.249
123	10.4.71.250/32	10.4.71.250 – 10.4.71.250	10.4.71.250
124	10.4.71.251/32	10.4.71.251 – 10.4.71.251	10.4.71.251
125	10.4.71.252/32	10.4.71.252 – 10.4.71.252	10.4.71.252
126	10.4.71.253/32	10.4.71.253 – 10.4.71.253	10.4.71.253
127	10.4.71.254/32	10.4.71.254 – 10.4.71.254	10.4.71.254
128	10.4.71.255/32	10.4.71.255 – 10.4.71.255	10.4.71.255

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 →