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)10.2.237.128/25

network10.2.237.128/25

broadcast10.2.237.255

first host10.2.237.129

last host10.2.237.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.2.237.128/25

address00001010.00000010.11101101.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000010.11101101.10000000

broadcast00001010.00000010.11101101.11111111

green = network part, grey = host part

hex0x0a02ed80

decimal167964032

reverse dns128.237.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:ed80

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.237.128/32	10.2.237.128 – 10.2.237.128	10.2.237.128
2	10.2.237.129/32	10.2.237.129 – 10.2.237.129	10.2.237.129
3	10.2.237.130/32	10.2.237.130 – 10.2.237.130	10.2.237.130
4	10.2.237.131/32	10.2.237.131 – 10.2.237.131	10.2.237.131
5	10.2.237.132/32	10.2.237.132 – 10.2.237.132	10.2.237.132
6	10.2.237.133/32	10.2.237.133 – 10.2.237.133	10.2.237.133
7	10.2.237.134/32	10.2.237.134 – 10.2.237.134	10.2.237.134
8	10.2.237.135/32	10.2.237.135 – 10.2.237.135	10.2.237.135
9	10.2.237.136/32	10.2.237.136 – 10.2.237.136	10.2.237.136
10	10.2.237.137/32	10.2.237.137 – 10.2.237.137	10.2.237.137
11	10.2.237.138/32	10.2.237.138 – 10.2.237.138	10.2.237.138
12	10.2.237.139/32	10.2.237.139 – 10.2.237.139	10.2.237.139
13	10.2.237.140/32	10.2.237.140 – 10.2.237.140	10.2.237.140
14	10.2.237.141/32	10.2.237.141 – 10.2.237.141	10.2.237.141
15	10.2.237.142/32	10.2.237.142 – 10.2.237.142	10.2.237.142
16	10.2.237.143/32	10.2.237.143 – 10.2.237.143	10.2.237.143
17	10.2.237.144/32	10.2.237.144 – 10.2.237.144	10.2.237.144
18	10.2.237.145/32	10.2.237.145 – 10.2.237.145	10.2.237.145
19	10.2.237.146/32	10.2.237.146 – 10.2.237.146	10.2.237.146
20	10.2.237.147/32	10.2.237.147 – 10.2.237.147	10.2.237.147
21	10.2.237.148/32	10.2.237.148 – 10.2.237.148	10.2.237.148
22	10.2.237.149/32	10.2.237.149 – 10.2.237.149	10.2.237.149
23	10.2.237.150/32	10.2.237.150 – 10.2.237.150	10.2.237.150
24	10.2.237.151/32	10.2.237.151 – 10.2.237.151	10.2.237.151
25	10.2.237.152/32	10.2.237.152 – 10.2.237.152	10.2.237.152
26	10.2.237.153/32	10.2.237.153 – 10.2.237.153	10.2.237.153
27	10.2.237.154/32	10.2.237.154 – 10.2.237.154	10.2.237.154
28	10.2.237.155/32	10.2.237.155 – 10.2.237.155	10.2.237.155
29	10.2.237.156/32	10.2.237.156 – 10.2.237.156	10.2.237.156
30	10.2.237.157/32	10.2.237.157 – 10.2.237.157	10.2.237.157
31	10.2.237.158/32	10.2.237.158 – 10.2.237.158	10.2.237.158
32	10.2.237.159/32	10.2.237.159 – 10.2.237.159	10.2.237.159
33	10.2.237.160/32	10.2.237.160 – 10.2.237.160	10.2.237.160
34	10.2.237.161/32	10.2.237.161 – 10.2.237.161	10.2.237.161
35	10.2.237.162/32	10.2.237.162 – 10.2.237.162	10.2.237.162
36	10.2.237.163/32	10.2.237.163 – 10.2.237.163	10.2.237.163
37	10.2.237.164/32	10.2.237.164 – 10.2.237.164	10.2.237.164
38	10.2.237.165/32	10.2.237.165 – 10.2.237.165	10.2.237.165
39	10.2.237.166/32	10.2.237.166 – 10.2.237.166	10.2.237.166
40	10.2.237.167/32	10.2.237.167 – 10.2.237.167	10.2.237.167
41	10.2.237.168/32	10.2.237.168 – 10.2.237.168	10.2.237.168
42	10.2.237.169/32	10.2.237.169 – 10.2.237.169	10.2.237.169
43	10.2.237.170/32	10.2.237.170 – 10.2.237.170	10.2.237.170
44	10.2.237.171/32	10.2.237.171 – 10.2.237.171	10.2.237.171
45	10.2.237.172/32	10.2.237.172 – 10.2.237.172	10.2.237.172
46	10.2.237.173/32	10.2.237.173 – 10.2.237.173	10.2.237.173
47	10.2.237.174/32	10.2.237.174 – 10.2.237.174	10.2.237.174
48	10.2.237.175/32	10.2.237.175 – 10.2.237.175	10.2.237.175
49	10.2.237.176/32	10.2.237.176 – 10.2.237.176	10.2.237.176
50	10.2.237.177/32	10.2.237.177 – 10.2.237.177	10.2.237.177
51	10.2.237.178/32	10.2.237.178 – 10.2.237.178	10.2.237.178
52	10.2.237.179/32	10.2.237.179 – 10.2.237.179	10.2.237.179
53	10.2.237.180/32	10.2.237.180 – 10.2.237.180	10.2.237.180
54	10.2.237.181/32	10.2.237.181 – 10.2.237.181	10.2.237.181
55	10.2.237.182/32	10.2.237.182 – 10.2.237.182	10.2.237.182
56	10.2.237.183/32	10.2.237.183 – 10.2.237.183	10.2.237.183
57	10.2.237.184/32	10.2.237.184 – 10.2.237.184	10.2.237.184
58	10.2.237.185/32	10.2.237.185 – 10.2.237.185	10.2.237.185
59	10.2.237.186/32	10.2.237.186 – 10.2.237.186	10.2.237.186
60	10.2.237.187/32	10.2.237.187 – 10.2.237.187	10.2.237.187
61	10.2.237.188/32	10.2.237.188 – 10.2.237.188	10.2.237.188
62	10.2.237.189/32	10.2.237.189 – 10.2.237.189	10.2.237.189
63	10.2.237.190/32	10.2.237.190 – 10.2.237.190	10.2.237.190
64	10.2.237.191/32	10.2.237.191 – 10.2.237.191	10.2.237.191
65	10.2.237.192/32	10.2.237.192 – 10.2.237.192	10.2.237.192
66	10.2.237.193/32	10.2.237.193 – 10.2.237.193	10.2.237.193
67	10.2.237.194/32	10.2.237.194 – 10.2.237.194	10.2.237.194
68	10.2.237.195/32	10.2.237.195 – 10.2.237.195	10.2.237.195
69	10.2.237.196/32	10.2.237.196 – 10.2.237.196	10.2.237.196
70	10.2.237.197/32	10.2.237.197 – 10.2.237.197	10.2.237.197
71	10.2.237.198/32	10.2.237.198 – 10.2.237.198	10.2.237.198
72	10.2.237.199/32	10.2.237.199 – 10.2.237.199	10.2.237.199
73	10.2.237.200/32	10.2.237.200 – 10.2.237.200	10.2.237.200
74	10.2.237.201/32	10.2.237.201 – 10.2.237.201	10.2.237.201
75	10.2.237.202/32	10.2.237.202 – 10.2.237.202	10.2.237.202
76	10.2.237.203/32	10.2.237.203 – 10.2.237.203	10.2.237.203
77	10.2.237.204/32	10.2.237.204 – 10.2.237.204	10.2.237.204
78	10.2.237.205/32	10.2.237.205 – 10.2.237.205	10.2.237.205
79	10.2.237.206/32	10.2.237.206 – 10.2.237.206	10.2.237.206
80	10.2.237.207/32	10.2.237.207 – 10.2.237.207	10.2.237.207
81	10.2.237.208/32	10.2.237.208 – 10.2.237.208	10.2.237.208
82	10.2.237.209/32	10.2.237.209 – 10.2.237.209	10.2.237.209
83	10.2.237.210/32	10.2.237.210 – 10.2.237.210	10.2.237.210
84	10.2.237.211/32	10.2.237.211 – 10.2.237.211	10.2.237.211
85	10.2.237.212/32	10.2.237.212 – 10.2.237.212	10.2.237.212
86	10.2.237.213/32	10.2.237.213 – 10.2.237.213	10.2.237.213
87	10.2.237.214/32	10.2.237.214 – 10.2.237.214	10.2.237.214
88	10.2.237.215/32	10.2.237.215 – 10.2.237.215	10.2.237.215
89	10.2.237.216/32	10.2.237.216 – 10.2.237.216	10.2.237.216
90	10.2.237.217/32	10.2.237.217 – 10.2.237.217	10.2.237.217
91	10.2.237.218/32	10.2.237.218 – 10.2.237.218	10.2.237.218
92	10.2.237.219/32	10.2.237.219 – 10.2.237.219	10.2.237.219
93	10.2.237.220/32	10.2.237.220 – 10.2.237.220	10.2.237.220
94	10.2.237.221/32	10.2.237.221 – 10.2.237.221	10.2.237.221
95	10.2.237.222/32	10.2.237.222 – 10.2.237.222	10.2.237.222
96	10.2.237.223/32	10.2.237.223 – 10.2.237.223	10.2.237.223
97	10.2.237.224/32	10.2.237.224 – 10.2.237.224	10.2.237.224
98	10.2.237.225/32	10.2.237.225 – 10.2.237.225	10.2.237.225
99	10.2.237.226/32	10.2.237.226 – 10.2.237.226	10.2.237.226
100	10.2.237.227/32	10.2.237.227 – 10.2.237.227	10.2.237.227
101	10.2.237.228/32	10.2.237.228 – 10.2.237.228	10.2.237.228
102	10.2.237.229/32	10.2.237.229 – 10.2.237.229	10.2.237.229
103	10.2.237.230/32	10.2.237.230 – 10.2.237.230	10.2.237.230
104	10.2.237.231/32	10.2.237.231 – 10.2.237.231	10.2.237.231
105	10.2.237.232/32	10.2.237.232 – 10.2.237.232	10.2.237.232
106	10.2.237.233/32	10.2.237.233 – 10.2.237.233	10.2.237.233
107	10.2.237.234/32	10.2.237.234 – 10.2.237.234	10.2.237.234
108	10.2.237.235/32	10.2.237.235 – 10.2.237.235	10.2.237.235
109	10.2.237.236/32	10.2.237.236 – 10.2.237.236	10.2.237.236
110	10.2.237.237/32	10.2.237.237 – 10.2.237.237	10.2.237.237
111	10.2.237.238/32	10.2.237.238 – 10.2.237.238	10.2.237.238
112	10.2.237.239/32	10.2.237.239 – 10.2.237.239	10.2.237.239
113	10.2.237.240/32	10.2.237.240 – 10.2.237.240	10.2.237.240
114	10.2.237.241/32	10.2.237.241 – 10.2.237.241	10.2.237.241
115	10.2.237.242/32	10.2.237.242 – 10.2.237.242	10.2.237.242
116	10.2.237.243/32	10.2.237.243 – 10.2.237.243	10.2.237.243
117	10.2.237.244/32	10.2.237.244 – 10.2.237.244	10.2.237.244
118	10.2.237.245/32	10.2.237.245 – 10.2.237.245	10.2.237.245
119	10.2.237.246/32	10.2.237.246 – 10.2.237.246	10.2.237.246
120	10.2.237.247/32	10.2.237.247 – 10.2.237.247	10.2.237.247
121	10.2.237.248/32	10.2.237.248 – 10.2.237.248	10.2.237.248
122	10.2.237.249/32	10.2.237.249 – 10.2.237.249	10.2.237.249
123	10.2.237.250/32	10.2.237.250 – 10.2.237.250	10.2.237.250
124	10.2.237.251/32	10.2.237.251 – 10.2.237.251	10.2.237.251
125	10.2.237.252/32	10.2.237.252 – 10.2.237.252	10.2.237.252
126	10.2.237.253/32	10.2.237.253 – 10.2.237.253	10.2.237.253
127	10.2.237.254/32	10.2.237.254 – 10.2.237.254	10.2.237.254
128	10.2.237.255/32	10.2.237.255 – 10.2.237.255	10.2.237.255

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 →