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)10.131.0.128/25

network10.131.0.128/25

broadcast10.131.0.255

first host10.131.0.129

last host10.131.0.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.131.0.128/25

address00001010.10000011.00000000.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.10000011.00000000.10000000

broadcast00001010.10000011.00000000.11111111

green = network part, grey = host part

hex0x0a830080

decimal176357504

reverse dns128.0.131.10.in-addr.arpa

ipv4-mapped::ffff:a83:80

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.131.0.128/32	10.131.0.128 – 10.131.0.128	10.131.0.128
2	10.131.0.129/32	10.131.0.129 – 10.131.0.129	10.131.0.129
3	10.131.0.130/32	10.131.0.130 – 10.131.0.130	10.131.0.130
4	10.131.0.131/32	10.131.0.131 – 10.131.0.131	10.131.0.131
5	10.131.0.132/32	10.131.0.132 – 10.131.0.132	10.131.0.132
6	10.131.0.133/32	10.131.0.133 – 10.131.0.133	10.131.0.133
7	10.131.0.134/32	10.131.0.134 – 10.131.0.134	10.131.0.134
8	10.131.0.135/32	10.131.0.135 – 10.131.0.135	10.131.0.135
9	10.131.0.136/32	10.131.0.136 – 10.131.0.136	10.131.0.136
10	10.131.0.137/32	10.131.0.137 – 10.131.0.137	10.131.0.137
11	10.131.0.138/32	10.131.0.138 – 10.131.0.138	10.131.0.138
12	10.131.0.139/32	10.131.0.139 – 10.131.0.139	10.131.0.139
13	10.131.0.140/32	10.131.0.140 – 10.131.0.140	10.131.0.140
14	10.131.0.141/32	10.131.0.141 – 10.131.0.141	10.131.0.141
15	10.131.0.142/32	10.131.0.142 – 10.131.0.142	10.131.0.142
16	10.131.0.143/32	10.131.0.143 – 10.131.0.143	10.131.0.143
17	10.131.0.144/32	10.131.0.144 – 10.131.0.144	10.131.0.144
18	10.131.0.145/32	10.131.0.145 – 10.131.0.145	10.131.0.145
19	10.131.0.146/32	10.131.0.146 – 10.131.0.146	10.131.0.146
20	10.131.0.147/32	10.131.0.147 – 10.131.0.147	10.131.0.147
21	10.131.0.148/32	10.131.0.148 – 10.131.0.148	10.131.0.148
22	10.131.0.149/32	10.131.0.149 – 10.131.0.149	10.131.0.149
23	10.131.0.150/32	10.131.0.150 – 10.131.0.150	10.131.0.150
24	10.131.0.151/32	10.131.0.151 – 10.131.0.151	10.131.0.151
25	10.131.0.152/32	10.131.0.152 – 10.131.0.152	10.131.0.152
26	10.131.0.153/32	10.131.0.153 – 10.131.0.153	10.131.0.153
27	10.131.0.154/32	10.131.0.154 – 10.131.0.154	10.131.0.154
28	10.131.0.155/32	10.131.0.155 – 10.131.0.155	10.131.0.155
29	10.131.0.156/32	10.131.0.156 – 10.131.0.156	10.131.0.156
30	10.131.0.157/32	10.131.0.157 – 10.131.0.157	10.131.0.157
31	10.131.0.158/32	10.131.0.158 – 10.131.0.158	10.131.0.158
32	10.131.0.159/32	10.131.0.159 – 10.131.0.159	10.131.0.159
33	10.131.0.160/32	10.131.0.160 – 10.131.0.160	10.131.0.160
34	10.131.0.161/32	10.131.0.161 – 10.131.0.161	10.131.0.161
35	10.131.0.162/32	10.131.0.162 – 10.131.0.162	10.131.0.162
36	10.131.0.163/32	10.131.0.163 – 10.131.0.163	10.131.0.163
37	10.131.0.164/32	10.131.0.164 – 10.131.0.164	10.131.0.164
38	10.131.0.165/32	10.131.0.165 – 10.131.0.165	10.131.0.165
39	10.131.0.166/32	10.131.0.166 – 10.131.0.166	10.131.0.166
40	10.131.0.167/32	10.131.0.167 – 10.131.0.167	10.131.0.167
41	10.131.0.168/32	10.131.0.168 – 10.131.0.168	10.131.0.168
42	10.131.0.169/32	10.131.0.169 – 10.131.0.169	10.131.0.169
43	10.131.0.170/32	10.131.0.170 – 10.131.0.170	10.131.0.170
44	10.131.0.171/32	10.131.0.171 – 10.131.0.171	10.131.0.171
45	10.131.0.172/32	10.131.0.172 – 10.131.0.172	10.131.0.172
46	10.131.0.173/32	10.131.0.173 – 10.131.0.173	10.131.0.173
47	10.131.0.174/32	10.131.0.174 – 10.131.0.174	10.131.0.174
48	10.131.0.175/32	10.131.0.175 – 10.131.0.175	10.131.0.175
49	10.131.0.176/32	10.131.0.176 – 10.131.0.176	10.131.0.176
50	10.131.0.177/32	10.131.0.177 – 10.131.0.177	10.131.0.177
51	10.131.0.178/32	10.131.0.178 – 10.131.0.178	10.131.0.178
52	10.131.0.179/32	10.131.0.179 – 10.131.0.179	10.131.0.179
53	10.131.0.180/32	10.131.0.180 – 10.131.0.180	10.131.0.180
54	10.131.0.181/32	10.131.0.181 – 10.131.0.181	10.131.0.181
55	10.131.0.182/32	10.131.0.182 – 10.131.0.182	10.131.0.182
56	10.131.0.183/32	10.131.0.183 – 10.131.0.183	10.131.0.183
57	10.131.0.184/32	10.131.0.184 – 10.131.0.184	10.131.0.184
58	10.131.0.185/32	10.131.0.185 – 10.131.0.185	10.131.0.185
59	10.131.0.186/32	10.131.0.186 – 10.131.0.186	10.131.0.186
60	10.131.0.187/32	10.131.0.187 – 10.131.0.187	10.131.0.187
61	10.131.0.188/32	10.131.0.188 – 10.131.0.188	10.131.0.188
62	10.131.0.189/32	10.131.0.189 – 10.131.0.189	10.131.0.189
63	10.131.0.190/32	10.131.0.190 – 10.131.0.190	10.131.0.190
64	10.131.0.191/32	10.131.0.191 – 10.131.0.191	10.131.0.191
65	10.131.0.192/32	10.131.0.192 – 10.131.0.192	10.131.0.192
66	10.131.0.193/32	10.131.0.193 – 10.131.0.193	10.131.0.193
67	10.131.0.194/32	10.131.0.194 – 10.131.0.194	10.131.0.194
68	10.131.0.195/32	10.131.0.195 – 10.131.0.195	10.131.0.195
69	10.131.0.196/32	10.131.0.196 – 10.131.0.196	10.131.0.196
70	10.131.0.197/32	10.131.0.197 – 10.131.0.197	10.131.0.197
71	10.131.0.198/32	10.131.0.198 – 10.131.0.198	10.131.0.198
72	10.131.0.199/32	10.131.0.199 – 10.131.0.199	10.131.0.199
73	10.131.0.200/32	10.131.0.200 – 10.131.0.200	10.131.0.200
74	10.131.0.201/32	10.131.0.201 – 10.131.0.201	10.131.0.201
75	10.131.0.202/32	10.131.0.202 – 10.131.0.202	10.131.0.202
76	10.131.0.203/32	10.131.0.203 – 10.131.0.203	10.131.0.203
77	10.131.0.204/32	10.131.0.204 – 10.131.0.204	10.131.0.204
78	10.131.0.205/32	10.131.0.205 – 10.131.0.205	10.131.0.205
79	10.131.0.206/32	10.131.0.206 – 10.131.0.206	10.131.0.206
80	10.131.0.207/32	10.131.0.207 – 10.131.0.207	10.131.0.207
81	10.131.0.208/32	10.131.0.208 – 10.131.0.208	10.131.0.208
82	10.131.0.209/32	10.131.0.209 – 10.131.0.209	10.131.0.209
83	10.131.0.210/32	10.131.0.210 – 10.131.0.210	10.131.0.210
84	10.131.0.211/32	10.131.0.211 – 10.131.0.211	10.131.0.211
85	10.131.0.212/32	10.131.0.212 – 10.131.0.212	10.131.0.212
86	10.131.0.213/32	10.131.0.213 – 10.131.0.213	10.131.0.213
87	10.131.0.214/32	10.131.0.214 – 10.131.0.214	10.131.0.214
88	10.131.0.215/32	10.131.0.215 – 10.131.0.215	10.131.0.215
89	10.131.0.216/32	10.131.0.216 – 10.131.0.216	10.131.0.216
90	10.131.0.217/32	10.131.0.217 – 10.131.0.217	10.131.0.217
91	10.131.0.218/32	10.131.0.218 – 10.131.0.218	10.131.0.218
92	10.131.0.219/32	10.131.0.219 – 10.131.0.219	10.131.0.219
93	10.131.0.220/32	10.131.0.220 – 10.131.0.220	10.131.0.220
94	10.131.0.221/32	10.131.0.221 – 10.131.0.221	10.131.0.221
95	10.131.0.222/32	10.131.0.222 – 10.131.0.222	10.131.0.222
96	10.131.0.223/32	10.131.0.223 – 10.131.0.223	10.131.0.223
97	10.131.0.224/32	10.131.0.224 – 10.131.0.224	10.131.0.224
98	10.131.0.225/32	10.131.0.225 – 10.131.0.225	10.131.0.225
99	10.131.0.226/32	10.131.0.226 – 10.131.0.226	10.131.0.226
100	10.131.0.227/32	10.131.0.227 – 10.131.0.227	10.131.0.227
101	10.131.0.228/32	10.131.0.228 – 10.131.0.228	10.131.0.228
102	10.131.0.229/32	10.131.0.229 – 10.131.0.229	10.131.0.229
103	10.131.0.230/32	10.131.0.230 – 10.131.0.230	10.131.0.230
104	10.131.0.231/32	10.131.0.231 – 10.131.0.231	10.131.0.231
105	10.131.0.232/32	10.131.0.232 – 10.131.0.232	10.131.0.232
106	10.131.0.233/32	10.131.0.233 – 10.131.0.233	10.131.0.233
107	10.131.0.234/32	10.131.0.234 – 10.131.0.234	10.131.0.234
108	10.131.0.235/32	10.131.0.235 – 10.131.0.235	10.131.0.235
109	10.131.0.236/32	10.131.0.236 – 10.131.0.236	10.131.0.236
110	10.131.0.237/32	10.131.0.237 – 10.131.0.237	10.131.0.237
111	10.131.0.238/32	10.131.0.238 – 10.131.0.238	10.131.0.238
112	10.131.0.239/32	10.131.0.239 – 10.131.0.239	10.131.0.239
113	10.131.0.240/32	10.131.0.240 – 10.131.0.240	10.131.0.240
114	10.131.0.241/32	10.131.0.241 – 10.131.0.241	10.131.0.241
115	10.131.0.242/32	10.131.0.242 – 10.131.0.242	10.131.0.242
116	10.131.0.243/32	10.131.0.243 – 10.131.0.243	10.131.0.243
117	10.131.0.244/32	10.131.0.244 – 10.131.0.244	10.131.0.244
118	10.131.0.245/32	10.131.0.245 – 10.131.0.245	10.131.0.245
119	10.131.0.246/32	10.131.0.246 – 10.131.0.246	10.131.0.246
120	10.131.0.247/32	10.131.0.247 – 10.131.0.247	10.131.0.247
121	10.131.0.248/32	10.131.0.248 – 10.131.0.248	10.131.0.248
122	10.131.0.249/32	10.131.0.249 – 10.131.0.249	10.131.0.249
123	10.131.0.250/32	10.131.0.250 – 10.131.0.250	10.131.0.250
124	10.131.0.251/32	10.131.0.251 – 10.131.0.251	10.131.0.251
125	10.131.0.252/32	10.131.0.252 – 10.131.0.252	10.131.0.252
126	10.131.0.253/32	10.131.0.253 – 10.131.0.253	10.131.0.253
127	10.131.0.254/32	10.131.0.254 – 10.131.0.254	10.131.0.254
128	10.131.0.255/32	10.131.0.255 – 10.131.0.255	10.131.0.255

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 →