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)10.87.2.128/25

network10.87.2.128/25

broadcast10.87.2.255

first host10.87.2.129

last host10.87.2.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.87.2.128/25

address00001010.01010111.00000010.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.01010111.00000010.10000000

broadcast00001010.01010111.00000010.11111111

green = network part, grey = host part

hex0x0a570280

decimal173474432

reverse dns128.2.87.10.in-addr.arpa

ipv4-mapped::ffff:a57:280

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.87.2.128/32	10.87.2.128 – 10.87.2.128	10.87.2.128
2	10.87.2.129/32	10.87.2.129 – 10.87.2.129	10.87.2.129
3	10.87.2.130/32	10.87.2.130 – 10.87.2.130	10.87.2.130
4	10.87.2.131/32	10.87.2.131 – 10.87.2.131	10.87.2.131
5	10.87.2.132/32	10.87.2.132 – 10.87.2.132	10.87.2.132
6	10.87.2.133/32	10.87.2.133 – 10.87.2.133	10.87.2.133
7	10.87.2.134/32	10.87.2.134 – 10.87.2.134	10.87.2.134
8	10.87.2.135/32	10.87.2.135 – 10.87.2.135	10.87.2.135
9	10.87.2.136/32	10.87.2.136 – 10.87.2.136	10.87.2.136
10	10.87.2.137/32	10.87.2.137 – 10.87.2.137	10.87.2.137
11	10.87.2.138/32	10.87.2.138 – 10.87.2.138	10.87.2.138
12	10.87.2.139/32	10.87.2.139 – 10.87.2.139	10.87.2.139
13	10.87.2.140/32	10.87.2.140 – 10.87.2.140	10.87.2.140
14	10.87.2.141/32	10.87.2.141 – 10.87.2.141	10.87.2.141
15	10.87.2.142/32	10.87.2.142 – 10.87.2.142	10.87.2.142
16	10.87.2.143/32	10.87.2.143 – 10.87.2.143	10.87.2.143
17	10.87.2.144/32	10.87.2.144 – 10.87.2.144	10.87.2.144
18	10.87.2.145/32	10.87.2.145 – 10.87.2.145	10.87.2.145
19	10.87.2.146/32	10.87.2.146 – 10.87.2.146	10.87.2.146
20	10.87.2.147/32	10.87.2.147 – 10.87.2.147	10.87.2.147
21	10.87.2.148/32	10.87.2.148 – 10.87.2.148	10.87.2.148
22	10.87.2.149/32	10.87.2.149 – 10.87.2.149	10.87.2.149
23	10.87.2.150/32	10.87.2.150 – 10.87.2.150	10.87.2.150
24	10.87.2.151/32	10.87.2.151 – 10.87.2.151	10.87.2.151
25	10.87.2.152/32	10.87.2.152 – 10.87.2.152	10.87.2.152
26	10.87.2.153/32	10.87.2.153 – 10.87.2.153	10.87.2.153
27	10.87.2.154/32	10.87.2.154 – 10.87.2.154	10.87.2.154
28	10.87.2.155/32	10.87.2.155 – 10.87.2.155	10.87.2.155
29	10.87.2.156/32	10.87.2.156 – 10.87.2.156	10.87.2.156
30	10.87.2.157/32	10.87.2.157 – 10.87.2.157	10.87.2.157
31	10.87.2.158/32	10.87.2.158 – 10.87.2.158	10.87.2.158
32	10.87.2.159/32	10.87.2.159 – 10.87.2.159	10.87.2.159
33	10.87.2.160/32	10.87.2.160 – 10.87.2.160	10.87.2.160
34	10.87.2.161/32	10.87.2.161 – 10.87.2.161	10.87.2.161
35	10.87.2.162/32	10.87.2.162 – 10.87.2.162	10.87.2.162
36	10.87.2.163/32	10.87.2.163 – 10.87.2.163	10.87.2.163
37	10.87.2.164/32	10.87.2.164 – 10.87.2.164	10.87.2.164
38	10.87.2.165/32	10.87.2.165 – 10.87.2.165	10.87.2.165
39	10.87.2.166/32	10.87.2.166 – 10.87.2.166	10.87.2.166
40	10.87.2.167/32	10.87.2.167 – 10.87.2.167	10.87.2.167
41	10.87.2.168/32	10.87.2.168 – 10.87.2.168	10.87.2.168
42	10.87.2.169/32	10.87.2.169 – 10.87.2.169	10.87.2.169
43	10.87.2.170/32	10.87.2.170 – 10.87.2.170	10.87.2.170
44	10.87.2.171/32	10.87.2.171 – 10.87.2.171	10.87.2.171
45	10.87.2.172/32	10.87.2.172 – 10.87.2.172	10.87.2.172
46	10.87.2.173/32	10.87.2.173 – 10.87.2.173	10.87.2.173
47	10.87.2.174/32	10.87.2.174 – 10.87.2.174	10.87.2.174
48	10.87.2.175/32	10.87.2.175 – 10.87.2.175	10.87.2.175
49	10.87.2.176/32	10.87.2.176 – 10.87.2.176	10.87.2.176
50	10.87.2.177/32	10.87.2.177 – 10.87.2.177	10.87.2.177
51	10.87.2.178/32	10.87.2.178 – 10.87.2.178	10.87.2.178
52	10.87.2.179/32	10.87.2.179 – 10.87.2.179	10.87.2.179
53	10.87.2.180/32	10.87.2.180 – 10.87.2.180	10.87.2.180
54	10.87.2.181/32	10.87.2.181 – 10.87.2.181	10.87.2.181
55	10.87.2.182/32	10.87.2.182 – 10.87.2.182	10.87.2.182
56	10.87.2.183/32	10.87.2.183 – 10.87.2.183	10.87.2.183
57	10.87.2.184/32	10.87.2.184 – 10.87.2.184	10.87.2.184
58	10.87.2.185/32	10.87.2.185 – 10.87.2.185	10.87.2.185
59	10.87.2.186/32	10.87.2.186 – 10.87.2.186	10.87.2.186
60	10.87.2.187/32	10.87.2.187 – 10.87.2.187	10.87.2.187
61	10.87.2.188/32	10.87.2.188 – 10.87.2.188	10.87.2.188
62	10.87.2.189/32	10.87.2.189 – 10.87.2.189	10.87.2.189
63	10.87.2.190/32	10.87.2.190 – 10.87.2.190	10.87.2.190
64	10.87.2.191/32	10.87.2.191 – 10.87.2.191	10.87.2.191
65	10.87.2.192/32	10.87.2.192 – 10.87.2.192	10.87.2.192
66	10.87.2.193/32	10.87.2.193 – 10.87.2.193	10.87.2.193
67	10.87.2.194/32	10.87.2.194 – 10.87.2.194	10.87.2.194
68	10.87.2.195/32	10.87.2.195 – 10.87.2.195	10.87.2.195
69	10.87.2.196/32	10.87.2.196 – 10.87.2.196	10.87.2.196
70	10.87.2.197/32	10.87.2.197 – 10.87.2.197	10.87.2.197
71	10.87.2.198/32	10.87.2.198 – 10.87.2.198	10.87.2.198
72	10.87.2.199/32	10.87.2.199 – 10.87.2.199	10.87.2.199
73	10.87.2.200/32	10.87.2.200 – 10.87.2.200	10.87.2.200
74	10.87.2.201/32	10.87.2.201 – 10.87.2.201	10.87.2.201
75	10.87.2.202/32	10.87.2.202 – 10.87.2.202	10.87.2.202
76	10.87.2.203/32	10.87.2.203 – 10.87.2.203	10.87.2.203
77	10.87.2.204/32	10.87.2.204 – 10.87.2.204	10.87.2.204
78	10.87.2.205/32	10.87.2.205 – 10.87.2.205	10.87.2.205
79	10.87.2.206/32	10.87.2.206 – 10.87.2.206	10.87.2.206
80	10.87.2.207/32	10.87.2.207 – 10.87.2.207	10.87.2.207
81	10.87.2.208/32	10.87.2.208 – 10.87.2.208	10.87.2.208
82	10.87.2.209/32	10.87.2.209 – 10.87.2.209	10.87.2.209
83	10.87.2.210/32	10.87.2.210 – 10.87.2.210	10.87.2.210
84	10.87.2.211/32	10.87.2.211 – 10.87.2.211	10.87.2.211
85	10.87.2.212/32	10.87.2.212 – 10.87.2.212	10.87.2.212
86	10.87.2.213/32	10.87.2.213 – 10.87.2.213	10.87.2.213
87	10.87.2.214/32	10.87.2.214 – 10.87.2.214	10.87.2.214
88	10.87.2.215/32	10.87.2.215 – 10.87.2.215	10.87.2.215
89	10.87.2.216/32	10.87.2.216 – 10.87.2.216	10.87.2.216
90	10.87.2.217/32	10.87.2.217 – 10.87.2.217	10.87.2.217
91	10.87.2.218/32	10.87.2.218 – 10.87.2.218	10.87.2.218
92	10.87.2.219/32	10.87.2.219 – 10.87.2.219	10.87.2.219
93	10.87.2.220/32	10.87.2.220 – 10.87.2.220	10.87.2.220
94	10.87.2.221/32	10.87.2.221 – 10.87.2.221	10.87.2.221
95	10.87.2.222/32	10.87.2.222 – 10.87.2.222	10.87.2.222
96	10.87.2.223/32	10.87.2.223 – 10.87.2.223	10.87.2.223
97	10.87.2.224/32	10.87.2.224 – 10.87.2.224	10.87.2.224
98	10.87.2.225/32	10.87.2.225 – 10.87.2.225	10.87.2.225
99	10.87.2.226/32	10.87.2.226 – 10.87.2.226	10.87.2.226
100	10.87.2.227/32	10.87.2.227 – 10.87.2.227	10.87.2.227
101	10.87.2.228/32	10.87.2.228 – 10.87.2.228	10.87.2.228
102	10.87.2.229/32	10.87.2.229 – 10.87.2.229	10.87.2.229
103	10.87.2.230/32	10.87.2.230 – 10.87.2.230	10.87.2.230
104	10.87.2.231/32	10.87.2.231 – 10.87.2.231	10.87.2.231
105	10.87.2.232/32	10.87.2.232 – 10.87.2.232	10.87.2.232
106	10.87.2.233/32	10.87.2.233 – 10.87.2.233	10.87.2.233
107	10.87.2.234/32	10.87.2.234 – 10.87.2.234	10.87.2.234
108	10.87.2.235/32	10.87.2.235 – 10.87.2.235	10.87.2.235
109	10.87.2.236/32	10.87.2.236 – 10.87.2.236	10.87.2.236
110	10.87.2.237/32	10.87.2.237 – 10.87.2.237	10.87.2.237
111	10.87.2.238/32	10.87.2.238 – 10.87.2.238	10.87.2.238
112	10.87.2.239/32	10.87.2.239 – 10.87.2.239	10.87.2.239
113	10.87.2.240/32	10.87.2.240 – 10.87.2.240	10.87.2.240
114	10.87.2.241/32	10.87.2.241 – 10.87.2.241	10.87.2.241
115	10.87.2.242/32	10.87.2.242 – 10.87.2.242	10.87.2.242
116	10.87.2.243/32	10.87.2.243 – 10.87.2.243	10.87.2.243
117	10.87.2.244/32	10.87.2.244 – 10.87.2.244	10.87.2.244
118	10.87.2.245/32	10.87.2.245 – 10.87.2.245	10.87.2.245
119	10.87.2.246/32	10.87.2.246 – 10.87.2.246	10.87.2.246
120	10.87.2.247/32	10.87.2.247 – 10.87.2.247	10.87.2.247
121	10.87.2.248/32	10.87.2.248 – 10.87.2.248	10.87.2.248
122	10.87.2.249/32	10.87.2.249 – 10.87.2.249	10.87.2.249
123	10.87.2.250/32	10.87.2.250 – 10.87.2.250	10.87.2.250
124	10.87.2.251/32	10.87.2.251 – 10.87.2.251	10.87.2.251
125	10.87.2.252/32	10.87.2.252 – 10.87.2.252	10.87.2.252
126	10.87.2.253/32	10.87.2.253 – 10.87.2.253	10.87.2.253
127	10.87.2.254/32	10.87.2.254 – 10.87.2.254	10.87.2.254
128	10.87.2.255/32	10.87.2.255 – 10.87.2.255	10.87.2.255

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 →