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)10.2.239.128/25

network10.2.239.128/25

broadcast10.2.239.255

first host10.2.239.129

last host10.2.239.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.2.239.128/25

address00001010.00000010.11101111.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000010.11101111.10000000

broadcast00001010.00000010.11101111.11111111

green = network part, grey = host part

hex0x0a02ef80

decimal167964544

reverse dns128.239.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:ef80

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.239.128/32	10.2.239.128 – 10.2.239.128	10.2.239.128
2	10.2.239.129/32	10.2.239.129 – 10.2.239.129	10.2.239.129
3	10.2.239.130/32	10.2.239.130 – 10.2.239.130	10.2.239.130
4	10.2.239.131/32	10.2.239.131 – 10.2.239.131	10.2.239.131
5	10.2.239.132/32	10.2.239.132 – 10.2.239.132	10.2.239.132
6	10.2.239.133/32	10.2.239.133 – 10.2.239.133	10.2.239.133
7	10.2.239.134/32	10.2.239.134 – 10.2.239.134	10.2.239.134
8	10.2.239.135/32	10.2.239.135 – 10.2.239.135	10.2.239.135
9	10.2.239.136/32	10.2.239.136 – 10.2.239.136	10.2.239.136
10	10.2.239.137/32	10.2.239.137 – 10.2.239.137	10.2.239.137
11	10.2.239.138/32	10.2.239.138 – 10.2.239.138	10.2.239.138
12	10.2.239.139/32	10.2.239.139 – 10.2.239.139	10.2.239.139
13	10.2.239.140/32	10.2.239.140 – 10.2.239.140	10.2.239.140
14	10.2.239.141/32	10.2.239.141 – 10.2.239.141	10.2.239.141
15	10.2.239.142/32	10.2.239.142 – 10.2.239.142	10.2.239.142
16	10.2.239.143/32	10.2.239.143 – 10.2.239.143	10.2.239.143
17	10.2.239.144/32	10.2.239.144 – 10.2.239.144	10.2.239.144
18	10.2.239.145/32	10.2.239.145 – 10.2.239.145	10.2.239.145
19	10.2.239.146/32	10.2.239.146 – 10.2.239.146	10.2.239.146
20	10.2.239.147/32	10.2.239.147 – 10.2.239.147	10.2.239.147
21	10.2.239.148/32	10.2.239.148 – 10.2.239.148	10.2.239.148
22	10.2.239.149/32	10.2.239.149 – 10.2.239.149	10.2.239.149
23	10.2.239.150/32	10.2.239.150 – 10.2.239.150	10.2.239.150
24	10.2.239.151/32	10.2.239.151 – 10.2.239.151	10.2.239.151
25	10.2.239.152/32	10.2.239.152 – 10.2.239.152	10.2.239.152
26	10.2.239.153/32	10.2.239.153 – 10.2.239.153	10.2.239.153
27	10.2.239.154/32	10.2.239.154 – 10.2.239.154	10.2.239.154
28	10.2.239.155/32	10.2.239.155 – 10.2.239.155	10.2.239.155
29	10.2.239.156/32	10.2.239.156 – 10.2.239.156	10.2.239.156
30	10.2.239.157/32	10.2.239.157 – 10.2.239.157	10.2.239.157
31	10.2.239.158/32	10.2.239.158 – 10.2.239.158	10.2.239.158
32	10.2.239.159/32	10.2.239.159 – 10.2.239.159	10.2.239.159
33	10.2.239.160/32	10.2.239.160 – 10.2.239.160	10.2.239.160
34	10.2.239.161/32	10.2.239.161 – 10.2.239.161	10.2.239.161
35	10.2.239.162/32	10.2.239.162 – 10.2.239.162	10.2.239.162
36	10.2.239.163/32	10.2.239.163 – 10.2.239.163	10.2.239.163
37	10.2.239.164/32	10.2.239.164 – 10.2.239.164	10.2.239.164
38	10.2.239.165/32	10.2.239.165 – 10.2.239.165	10.2.239.165
39	10.2.239.166/32	10.2.239.166 – 10.2.239.166	10.2.239.166
40	10.2.239.167/32	10.2.239.167 – 10.2.239.167	10.2.239.167
41	10.2.239.168/32	10.2.239.168 – 10.2.239.168	10.2.239.168
42	10.2.239.169/32	10.2.239.169 – 10.2.239.169	10.2.239.169
43	10.2.239.170/32	10.2.239.170 – 10.2.239.170	10.2.239.170
44	10.2.239.171/32	10.2.239.171 – 10.2.239.171	10.2.239.171
45	10.2.239.172/32	10.2.239.172 – 10.2.239.172	10.2.239.172
46	10.2.239.173/32	10.2.239.173 – 10.2.239.173	10.2.239.173
47	10.2.239.174/32	10.2.239.174 – 10.2.239.174	10.2.239.174
48	10.2.239.175/32	10.2.239.175 – 10.2.239.175	10.2.239.175
49	10.2.239.176/32	10.2.239.176 – 10.2.239.176	10.2.239.176
50	10.2.239.177/32	10.2.239.177 – 10.2.239.177	10.2.239.177
51	10.2.239.178/32	10.2.239.178 – 10.2.239.178	10.2.239.178
52	10.2.239.179/32	10.2.239.179 – 10.2.239.179	10.2.239.179
53	10.2.239.180/32	10.2.239.180 – 10.2.239.180	10.2.239.180
54	10.2.239.181/32	10.2.239.181 – 10.2.239.181	10.2.239.181
55	10.2.239.182/32	10.2.239.182 – 10.2.239.182	10.2.239.182
56	10.2.239.183/32	10.2.239.183 – 10.2.239.183	10.2.239.183
57	10.2.239.184/32	10.2.239.184 – 10.2.239.184	10.2.239.184
58	10.2.239.185/32	10.2.239.185 – 10.2.239.185	10.2.239.185
59	10.2.239.186/32	10.2.239.186 – 10.2.239.186	10.2.239.186
60	10.2.239.187/32	10.2.239.187 – 10.2.239.187	10.2.239.187
61	10.2.239.188/32	10.2.239.188 – 10.2.239.188	10.2.239.188
62	10.2.239.189/32	10.2.239.189 – 10.2.239.189	10.2.239.189
63	10.2.239.190/32	10.2.239.190 – 10.2.239.190	10.2.239.190
64	10.2.239.191/32	10.2.239.191 – 10.2.239.191	10.2.239.191
65	10.2.239.192/32	10.2.239.192 – 10.2.239.192	10.2.239.192
66	10.2.239.193/32	10.2.239.193 – 10.2.239.193	10.2.239.193
67	10.2.239.194/32	10.2.239.194 – 10.2.239.194	10.2.239.194
68	10.2.239.195/32	10.2.239.195 – 10.2.239.195	10.2.239.195
69	10.2.239.196/32	10.2.239.196 – 10.2.239.196	10.2.239.196
70	10.2.239.197/32	10.2.239.197 – 10.2.239.197	10.2.239.197
71	10.2.239.198/32	10.2.239.198 – 10.2.239.198	10.2.239.198
72	10.2.239.199/32	10.2.239.199 – 10.2.239.199	10.2.239.199
73	10.2.239.200/32	10.2.239.200 – 10.2.239.200	10.2.239.200
74	10.2.239.201/32	10.2.239.201 – 10.2.239.201	10.2.239.201
75	10.2.239.202/32	10.2.239.202 – 10.2.239.202	10.2.239.202
76	10.2.239.203/32	10.2.239.203 – 10.2.239.203	10.2.239.203
77	10.2.239.204/32	10.2.239.204 – 10.2.239.204	10.2.239.204
78	10.2.239.205/32	10.2.239.205 – 10.2.239.205	10.2.239.205
79	10.2.239.206/32	10.2.239.206 – 10.2.239.206	10.2.239.206
80	10.2.239.207/32	10.2.239.207 – 10.2.239.207	10.2.239.207
81	10.2.239.208/32	10.2.239.208 – 10.2.239.208	10.2.239.208
82	10.2.239.209/32	10.2.239.209 – 10.2.239.209	10.2.239.209
83	10.2.239.210/32	10.2.239.210 – 10.2.239.210	10.2.239.210
84	10.2.239.211/32	10.2.239.211 – 10.2.239.211	10.2.239.211
85	10.2.239.212/32	10.2.239.212 – 10.2.239.212	10.2.239.212
86	10.2.239.213/32	10.2.239.213 – 10.2.239.213	10.2.239.213
87	10.2.239.214/32	10.2.239.214 – 10.2.239.214	10.2.239.214
88	10.2.239.215/32	10.2.239.215 – 10.2.239.215	10.2.239.215
89	10.2.239.216/32	10.2.239.216 – 10.2.239.216	10.2.239.216
90	10.2.239.217/32	10.2.239.217 – 10.2.239.217	10.2.239.217
91	10.2.239.218/32	10.2.239.218 – 10.2.239.218	10.2.239.218
92	10.2.239.219/32	10.2.239.219 – 10.2.239.219	10.2.239.219
93	10.2.239.220/32	10.2.239.220 – 10.2.239.220	10.2.239.220
94	10.2.239.221/32	10.2.239.221 – 10.2.239.221	10.2.239.221
95	10.2.239.222/32	10.2.239.222 – 10.2.239.222	10.2.239.222
96	10.2.239.223/32	10.2.239.223 – 10.2.239.223	10.2.239.223
97	10.2.239.224/32	10.2.239.224 – 10.2.239.224	10.2.239.224
98	10.2.239.225/32	10.2.239.225 – 10.2.239.225	10.2.239.225
99	10.2.239.226/32	10.2.239.226 – 10.2.239.226	10.2.239.226
100	10.2.239.227/32	10.2.239.227 – 10.2.239.227	10.2.239.227
101	10.2.239.228/32	10.2.239.228 – 10.2.239.228	10.2.239.228
102	10.2.239.229/32	10.2.239.229 – 10.2.239.229	10.2.239.229
103	10.2.239.230/32	10.2.239.230 – 10.2.239.230	10.2.239.230
104	10.2.239.231/32	10.2.239.231 – 10.2.239.231	10.2.239.231
105	10.2.239.232/32	10.2.239.232 – 10.2.239.232	10.2.239.232
106	10.2.239.233/32	10.2.239.233 – 10.2.239.233	10.2.239.233
107	10.2.239.234/32	10.2.239.234 – 10.2.239.234	10.2.239.234
108	10.2.239.235/32	10.2.239.235 – 10.2.239.235	10.2.239.235
109	10.2.239.236/32	10.2.239.236 – 10.2.239.236	10.2.239.236
110	10.2.239.237/32	10.2.239.237 – 10.2.239.237	10.2.239.237
111	10.2.239.238/32	10.2.239.238 – 10.2.239.238	10.2.239.238
112	10.2.239.239/32	10.2.239.239 – 10.2.239.239	10.2.239.239
113	10.2.239.240/32	10.2.239.240 – 10.2.239.240	10.2.239.240
114	10.2.239.241/32	10.2.239.241 – 10.2.239.241	10.2.239.241
115	10.2.239.242/32	10.2.239.242 – 10.2.239.242	10.2.239.242
116	10.2.239.243/32	10.2.239.243 – 10.2.239.243	10.2.239.243
117	10.2.239.244/32	10.2.239.244 – 10.2.239.244	10.2.239.244
118	10.2.239.245/32	10.2.239.245 – 10.2.239.245	10.2.239.245
119	10.2.239.246/32	10.2.239.246 – 10.2.239.246	10.2.239.246
120	10.2.239.247/32	10.2.239.247 – 10.2.239.247	10.2.239.247
121	10.2.239.248/32	10.2.239.248 – 10.2.239.248	10.2.239.248
122	10.2.239.249/32	10.2.239.249 – 10.2.239.249	10.2.239.249
123	10.2.239.250/32	10.2.239.250 – 10.2.239.250	10.2.239.250
124	10.2.239.251/32	10.2.239.251 – 10.2.239.251	10.2.239.251
125	10.2.239.252/32	10.2.239.252 – 10.2.239.252	10.2.239.252
126	10.2.239.253/32	10.2.239.253 – 10.2.239.253	10.2.239.253
127	10.2.239.254/32	10.2.239.254 – 10.2.239.254	10.2.239.254
128	10.2.239.255/32	10.2.239.255 – 10.2.239.255	10.2.239.255

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 →