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)10.0.25.128/25

network10.0.25.128/25

broadcast10.0.25.255

first host10.0.25.129

last host10.0.25.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.0.25.128/25

address00001010.00000000.00011001.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000000.00011001.10000000

broadcast00001010.00000000.00011001.11111111

green = network part, grey = host part

hex0x0a001980

decimal167778688

reverse dns128.25.0.10.in-addr.arpa

ipv4-mapped::ffff:a00:1980

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.0.25.128/32	10.0.25.128 – 10.0.25.128	10.0.25.128
2	10.0.25.129/32	10.0.25.129 – 10.0.25.129	10.0.25.129
3	10.0.25.130/32	10.0.25.130 – 10.0.25.130	10.0.25.130
4	10.0.25.131/32	10.0.25.131 – 10.0.25.131	10.0.25.131
5	10.0.25.132/32	10.0.25.132 – 10.0.25.132	10.0.25.132
6	10.0.25.133/32	10.0.25.133 – 10.0.25.133	10.0.25.133
7	10.0.25.134/32	10.0.25.134 – 10.0.25.134	10.0.25.134
8	10.0.25.135/32	10.0.25.135 – 10.0.25.135	10.0.25.135
9	10.0.25.136/32	10.0.25.136 – 10.0.25.136	10.0.25.136
10	10.0.25.137/32	10.0.25.137 – 10.0.25.137	10.0.25.137
11	10.0.25.138/32	10.0.25.138 – 10.0.25.138	10.0.25.138
12	10.0.25.139/32	10.0.25.139 – 10.0.25.139	10.0.25.139
13	10.0.25.140/32	10.0.25.140 – 10.0.25.140	10.0.25.140
14	10.0.25.141/32	10.0.25.141 – 10.0.25.141	10.0.25.141
15	10.0.25.142/32	10.0.25.142 – 10.0.25.142	10.0.25.142
16	10.0.25.143/32	10.0.25.143 – 10.0.25.143	10.0.25.143
17	10.0.25.144/32	10.0.25.144 – 10.0.25.144	10.0.25.144
18	10.0.25.145/32	10.0.25.145 – 10.0.25.145	10.0.25.145
19	10.0.25.146/32	10.0.25.146 – 10.0.25.146	10.0.25.146
20	10.0.25.147/32	10.0.25.147 – 10.0.25.147	10.0.25.147
21	10.0.25.148/32	10.0.25.148 – 10.0.25.148	10.0.25.148
22	10.0.25.149/32	10.0.25.149 – 10.0.25.149	10.0.25.149
23	10.0.25.150/32	10.0.25.150 – 10.0.25.150	10.0.25.150
24	10.0.25.151/32	10.0.25.151 – 10.0.25.151	10.0.25.151
25	10.0.25.152/32	10.0.25.152 – 10.0.25.152	10.0.25.152
26	10.0.25.153/32	10.0.25.153 – 10.0.25.153	10.0.25.153
27	10.0.25.154/32	10.0.25.154 – 10.0.25.154	10.0.25.154
28	10.0.25.155/32	10.0.25.155 – 10.0.25.155	10.0.25.155
29	10.0.25.156/32	10.0.25.156 – 10.0.25.156	10.0.25.156
30	10.0.25.157/32	10.0.25.157 – 10.0.25.157	10.0.25.157
31	10.0.25.158/32	10.0.25.158 – 10.0.25.158	10.0.25.158
32	10.0.25.159/32	10.0.25.159 – 10.0.25.159	10.0.25.159
33	10.0.25.160/32	10.0.25.160 – 10.0.25.160	10.0.25.160
34	10.0.25.161/32	10.0.25.161 – 10.0.25.161	10.0.25.161
35	10.0.25.162/32	10.0.25.162 – 10.0.25.162	10.0.25.162
36	10.0.25.163/32	10.0.25.163 – 10.0.25.163	10.0.25.163
37	10.0.25.164/32	10.0.25.164 – 10.0.25.164	10.0.25.164
38	10.0.25.165/32	10.0.25.165 – 10.0.25.165	10.0.25.165
39	10.0.25.166/32	10.0.25.166 – 10.0.25.166	10.0.25.166
40	10.0.25.167/32	10.0.25.167 – 10.0.25.167	10.0.25.167
41	10.0.25.168/32	10.0.25.168 – 10.0.25.168	10.0.25.168
42	10.0.25.169/32	10.0.25.169 – 10.0.25.169	10.0.25.169
43	10.0.25.170/32	10.0.25.170 – 10.0.25.170	10.0.25.170
44	10.0.25.171/32	10.0.25.171 – 10.0.25.171	10.0.25.171
45	10.0.25.172/32	10.0.25.172 – 10.0.25.172	10.0.25.172
46	10.0.25.173/32	10.0.25.173 – 10.0.25.173	10.0.25.173
47	10.0.25.174/32	10.0.25.174 – 10.0.25.174	10.0.25.174
48	10.0.25.175/32	10.0.25.175 – 10.0.25.175	10.0.25.175
49	10.0.25.176/32	10.0.25.176 – 10.0.25.176	10.0.25.176
50	10.0.25.177/32	10.0.25.177 – 10.0.25.177	10.0.25.177
51	10.0.25.178/32	10.0.25.178 – 10.0.25.178	10.0.25.178
52	10.0.25.179/32	10.0.25.179 – 10.0.25.179	10.0.25.179
53	10.0.25.180/32	10.0.25.180 – 10.0.25.180	10.0.25.180
54	10.0.25.181/32	10.0.25.181 – 10.0.25.181	10.0.25.181
55	10.0.25.182/32	10.0.25.182 – 10.0.25.182	10.0.25.182
56	10.0.25.183/32	10.0.25.183 – 10.0.25.183	10.0.25.183
57	10.0.25.184/32	10.0.25.184 – 10.0.25.184	10.0.25.184
58	10.0.25.185/32	10.0.25.185 – 10.0.25.185	10.0.25.185
59	10.0.25.186/32	10.0.25.186 – 10.0.25.186	10.0.25.186
60	10.0.25.187/32	10.0.25.187 – 10.0.25.187	10.0.25.187
61	10.0.25.188/32	10.0.25.188 – 10.0.25.188	10.0.25.188
62	10.0.25.189/32	10.0.25.189 – 10.0.25.189	10.0.25.189
63	10.0.25.190/32	10.0.25.190 – 10.0.25.190	10.0.25.190
64	10.0.25.191/32	10.0.25.191 – 10.0.25.191	10.0.25.191
65	10.0.25.192/32	10.0.25.192 – 10.0.25.192	10.0.25.192
66	10.0.25.193/32	10.0.25.193 – 10.0.25.193	10.0.25.193
67	10.0.25.194/32	10.0.25.194 – 10.0.25.194	10.0.25.194
68	10.0.25.195/32	10.0.25.195 – 10.0.25.195	10.0.25.195
69	10.0.25.196/32	10.0.25.196 – 10.0.25.196	10.0.25.196
70	10.0.25.197/32	10.0.25.197 – 10.0.25.197	10.0.25.197
71	10.0.25.198/32	10.0.25.198 – 10.0.25.198	10.0.25.198
72	10.0.25.199/32	10.0.25.199 – 10.0.25.199	10.0.25.199
73	10.0.25.200/32	10.0.25.200 – 10.0.25.200	10.0.25.200
74	10.0.25.201/32	10.0.25.201 – 10.0.25.201	10.0.25.201
75	10.0.25.202/32	10.0.25.202 – 10.0.25.202	10.0.25.202
76	10.0.25.203/32	10.0.25.203 – 10.0.25.203	10.0.25.203
77	10.0.25.204/32	10.0.25.204 – 10.0.25.204	10.0.25.204
78	10.0.25.205/32	10.0.25.205 – 10.0.25.205	10.0.25.205
79	10.0.25.206/32	10.0.25.206 – 10.0.25.206	10.0.25.206
80	10.0.25.207/32	10.0.25.207 – 10.0.25.207	10.0.25.207
81	10.0.25.208/32	10.0.25.208 – 10.0.25.208	10.0.25.208
82	10.0.25.209/32	10.0.25.209 – 10.0.25.209	10.0.25.209
83	10.0.25.210/32	10.0.25.210 – 10.0.25.210	10.0.25.210
84	10.0.25.211/32	10.0.25.211 – 10.0.25.211	10.0.25.211
85	10.0.25.212/32	10.0.25.212 – 10.0.25.212	10.0.25.212
86	10.0.25.213/32	10.0.25.213 – 10.0.25.213	10.0.25.213
87	10.0.25.214/32	10.0.25.214 – 10.0.25.214	10.0.25.214
88	10.0.25.215/32	10.0.25.215 – 10.0.25.215	10.0.25.215
89	10.0.25.216/32	10.0.25.216 – 10.0.25.216	10.0.25.216
90	10.0.25.217/32	10.0.25.217 – 10.0.25.217	10.0.25.217
91	10.0.25.218/32	10.0.25.218 – 10.0.25.218	10.0.25.218
92	10.0.25.219/32	10.0.25.219 – 10.0.25.219	10.0.25.219
93	10.0.25.220/32	10.0.25.220 – 10.0.25.220	10.0.25.220
94	10.0.25.221/32	10.0.25.221 – 10.0.25.221	10.0.25.221
95	10.0.25.222/32	10.0.25.222 – 10.0.25.222	10.0.25.222
96	10.0.25.223/32	10.0.25.223 – 10.0.25.223	10.0.25.223
97	10.0.25.224/32	10.0.25.224 – 10.0.25.224	10.0.25.224
98	10.0.25.225/32	10.0.25.225 – 10.0.25.225	10.0.25.225
99	10.0.25.226/32	10.0.25.226 – 10.0.25.226	10.0.25.226
100	10.0.25.227/32	10.0.25.227 – 10.0.25.227	10.0.25.227
101	10.0.25.228/32	10.0.25.228 – 10.0.25.228	10.0.25.228
102	10.0.25.229/32	10.0.25.229 – 10.0.25.229	10.0.25.229
103	10.0.25.230/32	10.0.25.230 – 10.0.25.230	10.0.25.230
104	10.0.25.231/32	10.0.25.231 – 10.0.25.231	10.0.25.231
105	10.0.25.232/32	10.0.25.232 – 10.0.25.232	10.0.25.232
106	10.0.25.233/32	10.0.25.233 – 10.0.25.233	10.0.25.233
107	10.0.25.234/32	10.0.25.234 – 10.0.25.234	10.0.25.234
108	10.0.25.235/32	10.0.25.235 – 10.0.25.235	10.0.25.235
109	10.0.25.236/32	10.0.25.236 – 10.0.25.236	10.0.25.236
110	10.0.25.237/32	10.0.25.237 – 10.0.25.237	10.0.25.237
111	10.0.25.238/32	10.0.25.238 – 10.0.25.238	10.0.25.238
112	10.0.25.239/32	10.0.25.239 – 10.0.25.239	10.0.25.239
113	10.0.25.240/32	10.0.25.240 – 10.0.25.240	10.0.25.240
114	10.0.25.241/32	10.0.25.241 – 10.0.25.241	10.0.25.241
115	10.0.25.242/32	10.0.25.242 – 10.0.25.242	10.0.25.242
116	10.0.25.243/32	10.0.25.243 – 10.0.25.243	10.0.25.243
117	10.0.25.244/32	10.0.25.244 – 10.0.25.244	10.0.25.244
118	10.0.25.245/32	10.0.25.245 – 10.0.25.245	10.0.25.245
119	10.0.25.246/32	10.0.25.246 – 10.0.25.246	10.0.25.246
120	10.0.25.247/32	10.0.25.247 – 10.0.25.247	10.0.25.247
121	10.0.25.248/32	10.0.25.248 – 10.0.25.248	10.0.25.248
122	10.0.25.249/32	10.0.25.249 – 10.0.25.249	10.0.25.249
123	10.0.25.250/32	10.0.25.250 – 10.0.25.250	10.0.25.250
124	10.0.25.251/32	10.0.25.251 – 10.0.25.251	10.0.25.251
125	10.0.25.252/32	10.0.25.252 – 10.0.25.252	10.0.25.252
126	10.0.25.253/32	10.0.25.253 – 10.0.25.253	10.0.25.253
127	10.0.25.254/32	10.0.25.254 – 10.0.25.254	10.0.25.254
128	10.0.25.255/32	10.0.25.255 – 10.0.25.255	10.0.25.255

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 →