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)10.2.7.128/25

network10.2.7.128/25

broadcast10.2.7.255

first host10.2.7.129

last host10.2.7.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.2.7.128/25

address00001010.00000010.00000111.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000010.00000111.10000000

broadcast00001010.00000010.00000111.11111111

green = network part, grey = host part

hex0x0a020780

decimal167905152

reverse dns128.7.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:780

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.7.128/32	10.2.7.128 – 10.2.7.128	10.2.7.128
2	10.2.7.129/32	10.2.7.129 – 10.2.7.129	10.2.7.129
3	10.2.7.130/32	10.2.7.130 – 10.2.7.130	10.2.7.130
4	10.2.7.131/32	10.2.7.131 – 10.2.7.131	10.2.7.131
5	10.2.7.132/32	10.2.7.132 – 10.2.7.132	10.2.7.132
6	10.2.7.133/32	10.2.7.133 – 10.2.7.133	10.2.7.133
7	10.2.7.134/32	10.2.7.134 – 10.2.7.134	10.2.7.134
8	10.2.7.135/32	10.2.7.135 – 10.2.7.135	10.2.7.135
9	10.2.7.136/32	10.2.7.136 – 10.2.7.136	10.2.7.136
10	10.2.7.137/32	10.2.7.137 – 10.2.7.137	10.2.7.137
11	10.2.7.138/32	10.2.7.138 – 10.2.7.138	10.2.7.138
12	10.2.7.139/32	10.2.7.139 – 10.2.7.139	10.2.7.139
13	10.2.7.140/32	10.2.7.140 – 10.2.7.140	10.2.7.140
14	10.2.7.141/32	10.2.7.141 – 10.2.7.141	10.2.7.141
15	10.2.7.142/32	10.2.7.142 – 10.2.7.142	10.2.7.142
16	10.2.7.143/32	10.2.7.143 – 10.2.7.143	10.2.7.143
17	10.2.7.144/32	10.2.7.144 – 10.2.7.144	10.2.7.144
18	10.2.7.145/32	10.2.7.145 – 10.2.7.145	10.2.7.145
19	10.2.7.146/32	10.2.7.146 – 10.2.7.146	10.2.7.146
20	10.2.7.147/32	10.2.7.147 – 10.2.7.147	10.2.7.147
21	10.2.7.148/32	10.2.7.148 – 10.2.7.148	10.2.7.148
22	10.2.7.149/32	10.2.7.149 – 10.2.7.149	10.2.7.149
23	10.2.7.150/32	10.2.7.150 – 10.2.7.150	10.2.7.150
24	10.2.7.151/32	10.2.7.151 – 10.2.7.151	10.2.7.151
25	10.2.7.152/32	10.2.7.152 – 10.2.7.152	10.2.7.152
26	10.2.7.153/32	10.2.7.153 – 10.2.7.153	10.2.7.153
27	10.2.7.154/32	10.2.7.154 – 10.2.7.154	10.2.7.154
28	10.2.7.155/32	10.2.7.155 – 10.2.7.155	10.2.7.155
29	10.2.7.156/32	10.2.7.156 – 10.2.7.156	10.2.7.156
30	10.2.7.157/32	10.2.7.157 – 10.2.7.157	10.2.7.157
31	10.2.7.158/32	10.2.7.158 – 10.2.7.158	10.2.7.158
32	10.2.7.159/32	10.2.7.159 – 10.2.7.159	10.2.7.159
33	10.2.7.160/32	10.2.7.160 – 10.2.7.160	10.2.7.160
34	10.2.7.161/32	10.2.7.161 – 10.2.7.161	10.2.7.161
35	10.2.7.162/32	10.2.7.162 – 10.2.7.162	10.2.7.162
36	10.2.7.163/32	10.2.7.163 – 10.2.7.163	10.2.7.163
37	10.2.7.164/32	10.2.7.164 – 10.2.7.164	10.2.7.164
38	10.2.7.165/32	10.2.7.165 – 10.2.7.165	10.2.7.165
39	10.2.7.166/32	10.2.7.166 – 10.2.7.166	10.2.7.166
40	10.2.7.167/32	10.2.7.167 – 10.2.7.167	10.2.7.167
41	10.2.7.168/32	10.2.7.168 – 10.2.7.168	10.2.7.168
42	10.2.7.169/32	10.2.7.169 – 10.2.7.169	10.2.7.169
43	10.2.7.170/32	10.2.7.170 – 10.2.7.170	10.2.7.170
44	10.2.7.171/32	10.2.7.171 – 10.2.7.171	10.2.7.171
45	10.2.7.172/32	10.2.7.172 – 10.2.7.172	10.2.7.172
46	10.2.7.173/32	10.2.7.173 – 10.2.7.173	10.2.7.173
47	10.2.7.174/32	10.2.7.174 – 10.2.7.174	10.2.7.174
48	10.2.7.175/32	10.2.7.175 – 10.2.7.175	10.2.7.175
49	10.2.7.176/32	10.2.7.176 – 10.2.7.176	10.2.7.176
50	10.2.7.177/32	10.2.7.177 – 10.2.7.177	10.2.7.177
51	10.2.7.178/32	10.2.7.178 – 10.2.7.178	10.2.7.178
52	10.2.7.179/32	10.2.7.179 – 10.2.7.179	10.2.7.179
53	10.2.7.180/32	10.2.7.180 – 10.2.7.180	10.2.7.180
54	10.2.7.181/32	10.2.7.181 – 10.2.7.181	10.2.7.181
55	10.2.7.182/32	10.2.7.182 – 10.2.7.182	10.2.7.182
56	10.2.7.183/32	10.2.7.183 – 10.2.7.183	10.2.7.183
57	10.2.7.184/32	10.2.7.184 – 10.2.7.184	10.2.7.184
58	10.2.7.185/32	10.2.7.185 – 10.2.7.185	10.2.7.185
59	10.2.7.186/32	10.2.7.186 – 10.2.7.186	10.2.7.186
60	10.2.7.187/32	10.2.7.187 – 10.2.7.187	10.2.7.187
61	10.2.7.188/32	10.2.7.188 – 10.2.7.188	10.2.7.188
62	10.2.7.189/32	10.2.7.189 – 10.2.7.189	10.2.7.189
63	10.2.7.190/32	10.2.7.190 – 10.2.7.190	10.2.7.190
64	10.2.7.191/32	10.2.7.191 – 10.2.7.191	10.2.7.191
65	10.2.7.192/32	10.2.7.192 – 10.2.7.192	10.2.7.192
66	10.2.7.193/32	10.2.7.193 – 10.2.7.193	10.2.7.193
67	10.2.7.194/32	10.2.7.194 – 10.2.7.194	10.2.7.194
68	10.2.7.195/32	10.2.7.195 – 10.2.7.195	10.2.7.195
69	10.2.7.196/32	10.2.7.196 – 10.2.7.196	10.2.7.196
70	10.2.7.197/32	10.2.7.197 – 10.2.7.197	10.2.7.197
71	10.2.7.198/32	10.2.7.198 – 10.2.7.198	10.2.7.198
72	10.2.7.199/32	10.2.7.199 – 10.2.7.199	10.2.7.199
73	10.2.7.200/32	10.2.7.200 – 10.2.7.200	10.2.7.200
74	10.2.7.201/32	10.2.7.201 – 10.2.7.201	10.2.7.201
75	10.2.7.202/32	10.2.7.202 – 10.2.7.202	10.2.7.202
76	10.2.7.203/32	10.2.7.203 – 10.2.7.203	10.2.7.203
77	10.2.7.204/32	10.2.7.204 – 10.2.7.204	10.2.7.204
78	10.2.7.205/32	10.2.7.205 – 10.2.7.205	10.2.7.205
79	10.2.7.206/32	10.2.7.206 – 10.2.7.206	10.2.7.206
80	10.2.7.207/32	10.2.7.207 – 10.2.7.207	10.2.7.207
81	10.2.7.208/32	10.2.7.208 – 10.2.7.208	10.2.7.208
82	10.2.7.209/32	10.2.7.209 – 10.2.7.209	10.2.7.209
83	10.2.7.210/32	10.2.7.210 – 10.2.7.210	10.2.7.210
84	10.2.7.211/32	10.2.7.211 – 10.2.7.211	10.2.7.211
85	10.2.7.212/32	10.2.7.212 – 10.2.7.212	10.2.7.212
86	10.2.7.213/32	10.2.7.213 – 10.2.7.213	10.2.7.213
87	10.2.7.214/32	10.2.7.214 – 10.2.7.214	10.2.7.214
88	10.2.7.215/32	10.2.7.215 – 10.2.7.215	10.2.7.215
89	10.2.7.216/32	10.2.7.216 – 10.2.7.216	10.2.7.216
90	10.2.7.217/32	10.2.7.217 – 10.2.7.217	10.2.7.217
91	10.2.7.218/32	10.2.7.218 – 10.2.7.218	10.2.7.218
92	10.2.7.219/32	10.2.7.219 – 10.2.7.219	10.2.7.219
93	10.2.7.220/32	10.2.7.220 – 10.2.7.220	10.2.7.220
94	10.2.7.221/32	10.2.7.221 – 10.2.7.221	10.2.7.221
95	10.2.7.222/32	10.2.7.222 – 10.2.7.222	10.2.7.222
96	10.2.7.223/32	10.2.7.223 – 10.2.7.223	10.2.7.223
97	10.2.7.224/32	10.2.7.224 – 10.2.7.224	10.2.7.224
98	10.2.7.225/32	10.2.7.225 – 10.2.7.225	10.2.7.225
99	10.2.7.226/32	10.2.7.226 – 10.2.7.226	10.2.7.226
100	10.2.7.227/32	10.2.7.227 – 10.2.7.227	10.2.7.227
101	10.2.7.228/32	10.2.7.228 – 10.2.7.228	10.2.7.228
102	10.2.7.229/32	10.2.7.229 – 10.2.7.229	10.2.7.229
103	10.2.7.230/32	10.2.7.230 – 10.2.7.230	10.2.7.230
104	10.2.7.231/32	10.2.7.231 – 10.2.7.231	10.2.7.231
105	10.2.7.232/32	10.2.7.232 – 10.2.7.232	10.2.7.232
106	10.2.7.233/32	10.2.7.233 – 10.2.7.233	10.2.7.233
107	10.2.7.234/32	10.2.7.234 – 10.2.7.234	10.2.7.234
108	10.2.7.235/32	10.2.7.235 – 10.2.7.235	10.2.7.235
109	10.2.7.236/32	10.2.7.236 – 10.2.7.236	10.2.7.236
110	10.2.7.237/32	10.2.7.237 – 10.2.7.237	10.2.7.237
111	10.2.7.238/32	10.2.7.238 – 10.2.7.238	10.2.7.238
112	10.2.7.239/32	10.2.7.239 – 10.2.7.239	10.2.7.239
113	10.2.7.240/32	10.2.7.240 – 10.2.7.240	10.2.7.240
114	10.2.7.241/32	10.2.7.241 – 10.2.7.241	10.2.7.241
115	10.2.7.242/32	10.2.7.242 – 10.2.7.242	10.2.7.242
116	10.2.7.243/32	10.2.7.243 – 10.2.7.243	10.2.7.243
117	10.2.7.244/32	10.2.7.244 – 10.2.7.244	10.2.7.244
118	10.2.7.245/32	10.2.7.245 – 10.2.7.245	10.2.7.245
119	10.2.7.246/32	10.2.7.246 – 10.2.7.246	10.2.7.246
120	10.2.7.247/32	10.2.7.247 – 10.2.7.247	10.2.7.247
121	10.2.7.248/32	10.2.7.248 – 10.2.7.248	10.2.7.248
122	10.2.7.249/32	10.2.7.249 – 10.2.7.249	10.2.7.249
123	10.2.7.250/32	10.2.7.250 – 10.2.7.250	10.2.7.250
124	10.2.7.251/32	10.2.7.251 – 10.2.7.251	10.2.7.251
125	10.2.7.252/32	10.2.7.252 – 10.2.7.252	10.2.7.252
126	10.2.7.253/32	10.2.7.253 – 10.2.7.253	10.2.7.253
127	10.2.7.254/32	10.2.7.254 – 10.2.7.254	10.2.7.254
128	10.2.7.255/32	10.2.7.255 – 10.2.7.255	10.2.7.255

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 →