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)10.2.47.128/25

network10.2.47.128/25

broadcast10.2.47.255

first host10.2.47.129

last host10.2.47.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.2.47.128/25

address00001010.00000010.00101111.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000010.00101111.10000000

broadcast00001010.00000010.00101111.11111111

green = network part, grey = host part

hex0x0a022f80

decimal167915392

reverse dns128.47.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:2f80

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.47.128/32	10.2.47.128 – 10.2.47.128	10.2.47.128
2	10.2.47.129/32	10.2.47.129 – 10.2.47.129	10.2.47.129
3	10.2.47.130/32	10.2.47.130 – 10.2.47.130	10.2.47.130
4	10.2.47.131/32	10.2.47.131 – 10.2.47.131	10.2.47.131
5	10.2.47.132/32	10.2.47.132 – 10.2.47.132	10.2.47.132
6	10.2.47.133/32	10.2.47.133 – 10.2.47.133	10.2.47.133
7	10.2.47.134/32	10.2.47.134 – 10.2.47.134	10.2.47.134
8	10.2.47.135/32	10.2.47.135 – 10.2.47.135	10.2.47.135
9	10.2.47.136/32	10.2.47.136 – 10.2.47.136	10.2.47.136
10	10.2.47.137/32	10.2.47.137 – 10.2.47.137	10.2.47.137
11	10.2.47.138/32	10.2.47.138 – 10.2.47.138	10.2.47.138
12	10.2.47.139/32	10.2.47.139 – 10.2.47.139	10.2.47.139
13	10.2.47.140/32	10.2.47.140 – 10.2.47.140	10.2.47.140
14	10.2.47.141/32	10.2.47.141 – 10.2.47.141	10.2.47.141
15	10.2.47.142/32	10.2.47.142 – 10.2.47.142	10.2.47.142
16	10.2.47.143/32	10.2.47.143 – 10.2.47.143	10.2.47.143
17	10.2.47.144/32	10.2.47.144 – 10.2.47.144	10.2.47.144
18	10.2.47.145/32	10.2.47.145 – 10.2.47.145	10.2.47.145
19	10.2.47.146/32	10.2.47.146 – 10.2.47.146	10.2.47.146
20	10.2.47.147/32	10.2.47.147 – 10.2.47.147	10.2.47.147
21	10.2.47.148/32	10.2.47.148 – 10.2.47.148	10.2.47.148
22	10.2.47.149/32	10.2.47.149 – 10.2.47.149	10.2.47.149
23	10.2.47.150/32	10.2.47.150 – 10.2.47.150	10.2.47.150
24	10.2.47.151/32	10.2.47.151 – 10.2.47.151	10.2.47.151
25	10.2.47.152/32	10.2.47.152 – 10.2.47.152	10.2.47.152
26	10.2.47.153/32	10.2.47.153 – 10.2.47.153	10.2.47.153
27	10.2.47.154/32	10.2.47.154 – 10.2.47.154	10.2.47.154
28	10.2.47.155/32	10.2.47.155 – 10.2.47.155	10.2.47.155
29	10.2.47.156/32	10.2.47.156 – 10.2.47.156	10.2.47.156
30	10.2.47.157/32	10.2.47.157 – 10.2.47.157	10.2.47.157
31	10.2.47.158/32	10.2.47.158 – 10.2.47.158	10.2.47.158
32	10.2.47.159/32	10.2.47.159 – 10.2.47.159	10.2.47.159
33	10.2.47.160/32	10.2.47.160 – 10.2.47.160	10.2.47.160
34	10.2.47.161/32	10.2.47.161 – 10.2.47.161	10.2.47.161
35	10.2.47.162/32	10.2.47.162 – 10.2.47.162	10.2.47.162
36	10.2.47.163/32	10.2.47.163 – 10.2.47.163	10.2.47.163
37	10.2.47.164/32	10.2.47.164 – 10.2.47.164	10.2.47.164
38	10.2.47.165/32	10.2.47.165 – 10.2.47.165	10.2.47.165
39	10.2.47.166/32	10.2.47.166 – 10.2.47.166	10.2.47.166
40	10.2.47.167/32	10.2.47.167 – 10.2.47.167	10.2.47.167
41	10.2.47.168/32	10.2.47.168 – 10.2.47.168	10.2.47.168
42	10.2.47.169/32	10.2.47.169 – 10.2.47.169	10.2.47.169
43	10.2.47.170/32	10.2.47.170 – 10.2.47.170	10.2.47.170
44	10.2.47.171/32	10.2.47.171 – 10.2.47.171	10.2.47.171
45	10.2.47.172/32	10.2.47.172 – 10.2.47.172	10.2.47.172
46	10.2.47.173/32	10.2.47.173 – 10.2.47.173	10.2.47.173
47	10.2.47.174/32	10.2.47.174 – 10.2.47.174	10.2.47.174
48	10.2.47.175/32	10.2.47.175 – 10.2.47.175	10.2.47.175
49	10.2.47.176/32	10.2.47.176 – 10.2.47.176	10.2.47.176
50	10.2.47.177/32	10.2.47.177 – 10.2.47.177	10.2.47.177
51	10.2.47.178/32	10.2.47.178 – 10.2.47.178	10.2.47.178
52	10.2.47.179/32	10.2.47.179 – 10.2.47.179	10.2.47.179
53	10.2.47.180/32	10.2.47.180 – 10.2.47.180	10.2.47.180
54	10.2.47.181/32	10.2.47.181 – 10.2.47.181	10.2.47.181
55	10.2.47.182/32	10.2.47.182 – 10.2.47.182	10.2.47.182
56	10.2.47.183/32	10.2.47.183 – 10.2.47.183	10.2.47.183
57	10.2.47.184/32	10.2.47.184 – 10.2.47.184	10.2.47.184
58	10.2.47.185/32	10.2.47.185 – 10.2.47.185	10.2.47.185
59	10.2.47.186/32	10.2.47.186 – 10.2.47.186	10.2.47.186
60	10.2.47.187/32	10.2.47.187 – 10.2.47.187	10.2.47.187
61	10.2.47.188/32	10.2.47.188 – 10.2.47.188	10.2.47.188
62	10.2.47.189/32	10.2.47.189 – 10.2.47.189	10.2.47.189
63	10.2.47.190/32	10.2.47.190 – 10.2.47.190	10.2.47.190
64	10.2.47.191/32	10.2.47.191 – 10.2.47.191	10.2.47.191
65	10.2.47.192/32	10.2.47.192 – 10.2.47.192	10.2.47.192
66	10.2.47.193/32	10.2.47.193 – 10.2.47.193	10.2.47.193
67	10.2.47.194/32	10.2.47.194 – 10.2.47.194	10.2.47.194
68	10.2.47.195/32	10.2.47.195 – 10.2.47.195	10.2.47.195
69	10.2.47.196/32	10.2.47.196 – 10.2.47.196	10.2.47.196
70	10.2.47.197/32	10.2.47.197 – 10.2.47.197	10.2.47.197
71	10.2.47.198/32	10.2.47.198 – 10.2.47.198	10.2.47.198
72	10.2.47.199/32	10.2.47.199 – 10.2.47.199	10.2.47.199
73	10.2.47.200/32	10.2.47.200 – 10.2.47.200	10.2.47.200
74	10.2.47.201/32	10.2.47.201 – 10.2.47.201	10.2.47.201
75	10.2.47.202/32	10.2.47.202 – 10.2.47.202	10.2.47.202
76	10.2.47.203/32	10.2.47.203 – 10.2.47.203	10.2.47.203
77	10.2.47.204/32	10.2.47.204 – 10.2.47.204	10.2.47.204
78	10.2.47.205/32	10.2.47.205 – 10.2.47.205	10.2.47.205
79	10.2.47.206/32	10.2.47.206 – 10.2.47.206	10.2.47.206
80	10.2.47.207/32	10.2.47.207 – 10.2.47.207	10.2.47.207
81	10.2.47.208/32	10.2.47.208 – 10.2.47.208	10.2.47.208
82	10.2.47.209/32	10.2.47.209 – 10.2.47.209	10.2.47.209
83	10.2.47.210/32	10.2.47.210 – 10.2.47.210	10.2.47.210
84	10.2.47.211/32	10.2.47.211 – 10.2.47.211	10.2.47.211
85	10.2.47.212/32	10.2.47.212 – 10.2.47.212	10.2.47.212
86	10.2.47.213/32	10.2.47.213 – 10.2.47.213	10.2.47.213
87	10.2.47.214/32	10.2.47.214 – 10.2.47.214	10.2.47.214
88	10.2.47.215/32	10.2.47.215 – 10.2.47.215	10.2.47.215
89	10.2.47.216/32	10.2.47.216 – 10.2.47.216	10.2.47.216
90	10.2.47.217/32	10.2.47.217 – 10.2.47.217	10.2.47.217
91	10.2.47.218/32	10.2.47.218 – 10.2.47.218	10.2.47.218
92	10.2.47.219/32	10.2.47.219 – 10.2.47.219	10.2.47.219
93	10.2.47.220/32	10.2.47.220 – 10.2.47.220	10.2.47.220
94	10.2.47.221/32	10.2.47.221 – 10.2.47.221	10.2.47.221
95	10.2.47.222/32	10.2.47.222 – 10.2.47.222	10.2.47.222
96	10.2.47.223/32	10.2.47.223 – 10.2.47.223	10.2.47.223
97	10.2.47.224/32	10.2.47.224 – 10.2.47.224	10.2.47.224
98	10.2.47.225/32	10.2.47.225 – 10.2.47.225	10.2.47.225
99	10.2.47.226/32	10.2.47.226 – 10.2.47.226	10.2.47.226
100	10.2.47.227/32	10.2.47.227 – 10.2.47.227	10.2.47.227
101	10.2.47.228/32	10.2.47.228 – 10.2.47.228	10.2.47.228
102	10.2.47.229/32	10.2.47.229 – 10.2.47.229	10.2.47.229
103	10.2.47.230/32	10.2.47.230 – 10.2.47.230	10.2.47.230
104	10.2.47.231/32	10.2.47.231 – 10.2.47.231	10.2.47.231
105	10.2.47.232/32	10.2.47.232 – 10.2.47.232	10.2.47.232
106	10.2.47.233/32	10.2.47.233 – 10.2.47.233	10.2.47.233
107	10.2.47.234/32	10.2.47.234 – 10.2.47.234	10.2.47.234
108	10.2.47.235/32	10.2.47.235 – 10.2.47.235	10.2.47.235
109	10.2.47.236/32	10.2.47.236 – 10.2.47.236	10.2.47.236
110	10.2.47.237/32	10.2.47.237 – 10.2.47.237	10.2.47.237
111	10.2.47.238/32	10.2.47.238 – 10.2.47.238	10.2.47.238
112	10.2.47.239/32	10.2.47.239 – 10.2.47.239	10.2.47.239
113	10.2.47.240/32	10.2.47.240 – 10.2.47.240	10.2.47.240
114	10.2.47.241/32	10.2.47.241 – 10.2.47.241	10.2.47.241
115	10.2.47.242/32	10.2.47.242 – 10.2.47.242	10.2.47.242
116	10.2.47.243/32	10.2.47.243 – 10.2.47.243	10.2.47.243
117	10.2.47.244/32	10.2.47.244 – 10.2.47.244	10.2.47.244
118	10.2.47.245/32	10.2.47.245 – 10.2.47.245	10.2.47.245
119	10.2.47.246/32	10.2.47.246 – 10.2.47.246	10.2.47.246
120	10.2.47.247/32	10.2.47.247 – 10.2.47.247	10.2.47.247
121	10.2.47.248/32	10.2.47.248 – 10.2.47.248	10.2.47.248
122	10.2.47.249/32	10.2.47.249 – 10.2.47.249	10.2.47.249
123	10.2.47.250/32	10.2.47.250 – 10.2.47.250	10.2.47.250
124	10.2.47.251/32	10.2.47.251 – 10.2.47.251	10.2.47.251
125	10.2.47.252/32	10.2.47.252 – 10.2.47.252	10.2.47.252
126	10.2.47.253/32	10.2.47.253 – 10.2.47.253	10.2.47.253
127	10.2.47.254/32	10.2.47.254 – 10.2.47.254	10.2.47.254
128	10.2.47.255/32	10.2.47.255 – 10.2.47.255	10.2.47.255

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 →