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)10.167.123.128/25

network10.167.123.128/25

broadcast10.167.123.255

first host10.167.123.129

last host10.167.123.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.167.123.128/25

address00001010.10100111.01111011.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.10100111.01111011.10000000

broadcast00001010.10100111.01111011.11111111

green = network part, grey = host part

hex0x0aa77b80

decimal178748288

reverse dns128.123.167.10.in-addr.arpa

ipv4-mapped::ffff:aa7:7b80

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.167.123.128/32	10.167.123.128 – 10.167.123.128	10.167.123.128
2	10.167.123.129/32	10.167.123.129 – 10.167.123.129	10.167.123.129
3	10.167.123.130/32	10.167.123.130 – 10.167.123.130	10.167.123.130
4	10.167.123.131/32	10.167.123.131 – 10.167.123.131	10.167.123.131
5	10.167.123.132/32	10.167.123.132 – 10.167.123.132	10.167.123.132
6	10.167.123.133/32	10.167.123.133 – 10.167.123.133	10.167.123.133
7	10.167.123.134/32	10.167.123.134 – 10.167.123.134	10.167.123.134
8	10.167.123.135/32	10.167.123.135 – 10.167.123.135	10.167.123.135
9	10.167.123.136/32	10.167.123.136 – 10.167.123.136	10.167.123.136
10	10.167.123.137/32	10.167.123.137 – 10.167.123.137	10.167.123.137
11	10.167.123.138/32	10.167.123.138 – 10.167.123.138	10.167.123.138
12	10.167.123.139/32	10.167.123.139 – 10.167.123.139	10.167.123.139
13	10.167.123.140/32	10.167.123.140 – 10.167.123.140	10.167.123.140
14	10.167.123.141/32	10.167.123.141 – 10.167.123.141	10.167.123.141
15	10.167.123.142/32	10.167.123.142 – 10.167.123.142	10.167.123.142
16	10.167.123.143/32	10.167.123.143 – 10.167.123.143	10.167.123.143
17	10.167.123.144/32	10.167.123.144 – 10.167.123.144	10.167.123.144
18	10.167.123.145/32	10.167.123.145 – 10.167.123.145	10.167.123.145
19	10.167.123.146/32	10.167.123.146 – 10.167.123.146	10.167.123.146
20	10.167.123.147/32	10.167.123.147 – 10.167.123.147	10.167.123.147
21	10.167.123.148/32	10.167.123.148 – 10.167.123.148	10.167.123.148
22	10.167.123.149/32	10.167.123.149 – 10.167.123.149	10.167.123.149
23	10.167.123.150/32	10.167.123.150 – 10.167.123.150	10.167.123.150
24	10.167.123.151/32	10.167.123.151 – 10.167.123.151	10.167.123.151
25	10.167.123.152/32	10.167.123.152 – 10.167.123.152	10.167.123.152
26	10.167.123.153/32	10.167.123.153 – 10.167.123.153	10.167.123.153
27	10.167.123.154/32	10.167.123.154 – 10.167.123.154	10.167.123.154
28	10.167.123.155/32	10.167.123.155 – 10.167.123.155	10.167.123.155
29	10.167.123.156/32	10.167.123.156 – 10.167.123.156	10.167.123.156
30	10.167.123.157/32	10.167.123.157 – 10.167.123.157	10.167.123.157
31	10.167.123.158/32	10.167.123.158 – 10.167.123.158	10.167.123.158
32	10.167.123.159/32	10.167.123.159 – 10.167.123.159	10.167.123.159
33	10.167.123.160/32	10.167.123.160 – 10.167.123.160	10.167.123.160
34	10.167.123.161/32	10.167.123.161 – 10.167.123.161	10.167.123.161
35	10.167.123.162/32	10.167.123.162 – 10.167.123.162	10.167.123.162
36	10.167.123.163/32	10.167.123.163 – 10.167.123.163	10.167.123.163
37	10.167.123.164/32	10.167.123.164 – 10.167.123.164	10.167.123.164
38	10.167.123.165/32	10.167.123.165 – 10.167.123.165	10.167.123.165
39	10.167.123.166/32	10.167.123.166 – 10.167.123.166	10.167.123.166
40	10.167.123.167/32	10.167.123.167 – 10.167.123.167	10.167.123.167
41	10.167.123.168/32	10.167.123.168 – 10.167.123.168	10.167.123.168
42	10.167.123.169/32	10.167.123.169 – 10.167.123.169	10.167.123.169
43	10.167.123.170/32	10.167.123.170 – 10.167.123.170	10.167.123.170
44	10.167.123.171/32	10.167.123.171 – 10.167.123.171	10.167.123.171
45	10.167.123.172/32	10.167.123.172 – 10.167.123.172	10.167.123.172
46	10.167.123.173/32	10.167.123.173 – 10.167.123.173	10.167.123.173
47	10.167.123.174/32	10.167.123.174 – 10.167.123.174	10.167.123.174
48	10.167.123.175/32	10.167.123.175 – 10.167.123.175	10.167.123.175
49	10.167.123.176/32	10.167.123.176 – 10.167.123.176	10.167.123.176
50	10.167.123.177/32	10.167.123.177 – 10.167.123.177	10.167.123.177
51	10.167.123.178/32	10.167.123.178 – 10.167.123.178	10.167.123.178
52	10.167.123.179/32	10.167.123.179 – 10.167.123.179	10.167.123.179
53	10.167.123.180/32	10.167.123.180 – 10.167.123.180	10.167.123.180
54	10.167.123.181/32	10.167.123.181 – 10.167.123.181	10.167.123.181
55	10.167.123.182/32	10.167.123.182 – 10.167.123.182	10.167.123.182
56	10.167.123.183/32	10.167.123.183 – 10.167.123.183	10.167.123.183
57	10.167.123.184/32	10.167.123.184 – 10.167.123.184	10.167.123.184
58	10.167.123.185/32	10.167.123.185 – 10.167.123.185	10.167.123.185
59	10.167.123.186/32	10.167.123.186 – 10.167.123.186	10.167.123.186
60	10.167.123.187/32	10.167.123.187 – 10.167.123.187	10.167.123.187
61	10.167.123.188/32	10.167.123.188 – 10.167.123.188	10.167.123.188
62	10.167.123.189/32	10.167.123.189 – 10.167.123.189	10.167.123.189
63	10.167.123.190/32	10.167.123.190 – 10.167.123.190	10.167.123.190
64	10.167.123.191/32	10.167.123.191 – 10.167.123.191	10.167.123.191
65	10.167.123.192/32	10.167.123.192 – 10.167.123.192	10.167.123.192
66	10.167.123.193/32	10.167.123.193 – 10.167.123.193	10.167.123.193
67	10.167.123.194/32	10.167.123.194 – 10.167.123.194	10.167.123.194
68	10.167.123.195/32	10.167.123.195 – 10.167.123.195	10.167.123.195
69	10.167.123.196/32	10.167.123.196 – 10.167.123.196	10.167.123.196
70	10.167.123.197/32	10.167.123.197 – 10.167.123.197	10.167.123.197
71	10.167.123.198/32	10.167.123.198 – 10.167.123.198	10.167.123.198
72	10.167.123.199/32	10.167.123.199 – 10.167.123.199	10.167.123.199
73	10.167.123.200/32	10.167.123.200 – 10.167.123.200	10.167.123.200
74	10.167.123.201/32	10.167.123.201 – 10.167.123.201	10.167.123.201
75	10.167.123.202/32	10.167.123.202 – 10.167.123.202	10.167.123.202
76	10.167.123.203/32	10.167.123.203 – 10.167.123.203	10.167.123.203
77	10.167.123.204/32	10.167.123.204 – 10.167.123.204	10.167.123.204
78	10.167.123.205/32	10.167.123.205 – 10.167.123.205	10.167.123.205
79	10.167.123.206/32	10.167.123.206 – 10.167.123.206	10.167.123.206
80	10.167.123.207/32	10.167.123.207 – 10.167.123.207	10.167.123.207
81	10.167.123.208/32	10.167.123.208 – 10.167.123.208	10.167.123.208
82	10.167.123.209/32	10.167.123.209 – 10.167.123.209	10.167.123.209
83	10.167.123.210/32	10.167.123.210 – 10.167.123.210	10.167.123.210
84	10.167.123.211/32	10.167.123.211 – 10.167.123.211	10.167.123.211
85	10.167.123.212/32	10.167.123.212 – 10.167.123.212	10.167.123.212
86	10.167.123.213/32	10.167.123.213 – 10.167.123.213	10.167.123.213
87	10.167.123.214/32	10.167.123.214 – 10.167.123.214	10.167.123.214
88	10.167.123.215/32	10.167.123.215 – 10.167.123.215	10.167.123.215
89	10.167.123.216/32	10.167.123.216 – 10.167.123.216	10.167.123.216
90	10.167.123.217/32	10.167.123.217 – 10.167.123.217	10.167.123.217
91	10.167.123.218/32	10.167.123.218 – 10.167.123.218	10.167.123.218
92	10.167.123.219/32	10.167.123.219 – 10.167.123.219	10.167.123.219
93	10.167.123.220/32	10.167.123.220 – 10.167.123.220	10.167.123.220
94	10.167.123.221/32	10.167.123.221 – 10.167.123.221	10.167.123.221
95	10.167.123.222/32	10.167.123.222 – 10.167.123.222	10.167.123.222
96	10.167.123.223/32	10.167.123.223 – 10.167.123.223	10.167.123.223
97	10.167.123.224/32	10.167.123.224 – 10.167.123.224	10.167.123.224
98	10.167.123.225/32	10.167.123.225 – 10.167.123.225	10.167.123.225
99	10.167.123.226/32	10.167.123.226 – 10.167.123.226	10.167.123.226
100	10.167.123.227/32	10.167.123.227 – 10.167.123.227	10.167.123.227
101	10.167.123.228/32	10.167.123.228 – 10.167.123.228	10.167.123.228
102	10.167.123.229/32	10.167.123.229 – 10.167.123.229	10.167.123.229
103	10.167.123.230/32	10.167.123.230 – 10.167.123.230	10.167.123.230
104	10.167.123.231/32	10.167.123.231 – 10.167.123.231	10.167.123.231
105	10.167.123.232/32	10.167.123.232 – 10.167.123.232	10.167.123.232
106	10.167.123.233/32	10.167.123.233 – 10.167.123.233	10.167.123.233
107	10.167.123.234/32	10.167.123.234 – 10.167.123.234	10.167.123.234
108	10.167.123.235/32	10.167.123.235 – 10.167.123.235	10.167.123.235
109	10.167.123.236/32	10.167.123.236 – 10.167.123.236	10.167.123.236
110	10.167.123.237/32	10.167.123.237 – 10.167.123.237	10.167.123.237
111	10.167.123.238/32	10.167.123.238 – 10.167.123.238	10.167.123.238
112	10.167.123.239/32	10.167.123.239 – 10.167.123.239	10.167.123.239
113	10.167.123.240/32	10.167.123.240 – 10.167.123.240	10.167.123.240
114	10.167.123.241/32	10.167.123.241 – 10.167.123.241	10.167.123.241
115	10.167.123.242/32	10.167.123.242 – 10.167.123.242	10.167.123.242
116	10.167.123.243/32	10.167.123.243 – 10.167.123.243	10.167.123.243
117	10.167.123.244/32	10.167.123.244 – 10.167.123.244	10.167.123.244
118	10.167.123.245/32	10.167.123.245 – 10.167.123.245	10.167.123.245
119	10.167.123.246/32	10.167.123.246 – 10.167.123.246	10.167.123.246
120	10.167.123.247/32	10.167.123.247 – 10.167.123.247	10.167.123.247
121	10.167.123.248/32	10.167.123.248 – 10.167.123.248	10.167.123.248
122	10.167.123.249/32	10.167.123.249 – 10.167.123.249	10.167.123.249
123	10.167.123.250/32	10.167.123.250 – 10.167.123.250	10.167.123.250
124	10.167.123.251/32	10.167.123.251 – 10.167.123.251	10.167.123.251
125	10.167.123.252/32	10.167.123.252 – 10.167.123.252	10.167.123.252
126	10.167.123.253/32	10.167.123.253 – 10.167.123.253	10.167.123.253
127	10.167.123.254/32	10.167.123.254 – 10.167.123.254	10.167.123.254
128	10.167.123.255/32	10.167.123.255 – 10.167.123.255	10.167.123.255

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 →