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)10.0.43.128/25

network10.0.43.128/25

broadcast10.0.43.255

first host10.0.43.129

last host10.0.43.254

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.0.43.128/25

address00001010.00000000.00101011.10000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000000.00101011.10000000

broadcast00001010.00000000.00101011.11111111

green = network part, grey = host part

hex0x0a002b80

decimal167783296

reverse dns128.43.0.10.in-addr.arpa

ipv4-mapped::ffff:a00:2b80

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.0.43.128/32	10.0.43.128 – 10.0.43.128	10.0.43.128
2	10.0.43.129/32	10.0.43.129 – 10.0.43.129	10.0.43.129
3	10.0.43.130/32	10.0.43.130 – 10.0.43.130	10.0.43.130
4	10.0.43.131/32	10.0.43.131 – 10.0.43.131	10.0.43.131
5	10.0.43.132/32	10.0.43.132 – 10.0.43.132	10.0.43.132
6	10.0.43.133/32	10.0.43.133 – 10.0.43.133	10.0.43.133
7	10.0.43.134/32	10.0.43.134 – 10.0.43.134	10.0.43.134
8	10.0.43.135/32	10.0.43.135 – 10.0.43.135	10.0.43.135
9	10.0.43.136/32	10.0.43.136 – 10.0.43.136	10.0.43.136
10	10.0.43.137/32	10.0.43.137 – 10.0.43.137	10.0.43.137
11	10.0.43.138/32	10.0.43.138 – 10.0.43.138	10.0.43.138
12	10.0.43.139/32	10.0.43.139 – 10.0.43.139	10.0.43.139
13	10.0.43.140/32	10.0.43.140 – 10.0.43.140	10.0.43.140
14	10.0.43.141/32	10.0.43.141 – 10.0.43.141	10.0.43.141
15	10.0.43.142/32	10.0.43.142 – 10.0.43.142	10.0.43.142
16	10.0.43.143/32	10.0.43.143 – 10.0.43.143	10.0.43.143
17	10.0.43.144/32	10.0.43.144 – 10.0.43.144	10.0.43.144
18	10.0.43.145/32	10.0.43.145 – 10.0.43.145	10.0.43.145
19	10.0.43.146/32	10.0.43.146 – 10.0.43.146	10.0.43.146
20	10.0.43.147/32	10.0.43.147 – 10.0.43.147	10.0.43.147
21	10.0.43.148/32	10.0.43.148 – 10.0.43.148	10.0.43.148
22	10.0.43.149/32	10.0.43.149 – 10.0.43.149	10.0.43.149
23	10.0.43.150/32	10.0.43.150 – 10.0.43.150	10.0.43.150
24	10.0.43.151/32	10.0.43.151 – 10.0.43.151	10.0.43.151
25	10.0.43.152/32	10.0.43.152 – 10.0.43.152	10.0.43.152
26	10.0.43.153/32	10.0.43.153 – 10.0.43.153	10.0.43.153
27	10.0.43.154/32	10.0.43.154 – 10.0.43.154	10.0.43.154
28	10.0.43.155/32	10.0.43.155 – 10.0.43.155	10.0.43.155
29	10.0.43.156/32	10.0.43.156 – 10.0.43.156	10.0.43.156
30	10.0.43.157/32	10.0.43.157 – 10.0.43.157	10.0.43.157
31	10.0.43.158/32	10.0.43.158 – 10.0.43.158	10.0.43.158
32	10.0.43.159/32	10.0.43.159 – 10.0.43.159	10.0.43.159
33	10.0.43.160/32	10.0.43.160 – 10.0.43.160	10.0.43.160
34	10.0.43.161/32	10.0.43.161 – 10.0.43.161	10.0.43.161
35	10.0.43.162/32	10.0.43.162 – 10.0.43.162	10.0.43.162
36	10.0.43.163/32	10.0.43.163 – 10.0.43.163	10.0.43.163
37	10.0.43.164/32	10.0.43.164 – 10.0.43.164	10.0.43.164
38	10.0.43.165/32	10.0.43.165 – 10.0.43.165	10.0.43.165
39	10.0.43.166/32	10.0.43.166 – 10.0.43.166	10.0.43.166
40	10.0.43.167/32	10.0.43.167 – 10.0.43.167	10.0.43.167
41	10.0.43.168/32	10.0.43.168 – 10.0.43.168	10.0.43.168
42	10.0.43.169/32	10.0.43.169 – 10.0.43.169	10.0.43.169
43	10.0.43.170/32	10.0.43.170 – 10.0.43.170	10.0.43.170
44	10.0.43.171/32	10.0.43.171 – 10.0.43.171	10.0.43.171
45	10.0.43.172/32	10.0.43.172 – 10.0.43.172	10.0.43.172
46	10.0.43.173/32	10.0.43.173 – 10.0.43.173	10.0.43.173
47	10.0.43.174/32	10.0.43.174 – 10.0.43.174	10.0.43.174
48	10.0.43.175/32	10.0.43.175 – 10.0.43.175	10.0.43.175
49	10.0.43.176/32	10.0.43.176 – 10.0.43.176	10.0.43.176
50	10.0.43.177/32	10.0.43.177 – 10.0.43.177	10.0.43.177
51	10.0.43.178/32	10.0.43.178 – 10.0.43.178	10.0.43.178
52	10.0.43.179/32	10.0.43.179 – 10.0.43.179	10.0.43.179
53	10.0.43.180/32	10.0.43.180 – 10.0.43.180	10.0.43.180
54	10.0.43.181/32	10.0.43.181 – 10.0.43.181	10.0.43.181
55	10.0.43.182/32	10.0.43.182 – 10.0.43.182	10.0.43.182
56	10.0.43.183/32	10.0.43.183 – 10.0.43.183	10.0.43.183
57	10.0.43.184/32	10.0.43.184 – 10.0.43.184	10.0.43.184
58	10.0.43.185/32	10.0.43.185 – 10.0.43.185	10.0.43.185
59	10.0.43.186/32	10.0.43.186 – 10.0.43.186	10.0.43.186
60	10.0.43.187/32	10.0.43.187 – 10.0.43.187	10.0.43.187
61	10.0.43.188/32	10.0.43.188 – 10.0.43.188	10.0.43.188
62	10.0.43.189/32	10.0.43.189 – 10.0.43.189	10.0.43.189
63	10.0.43.190/32	10.0.43.190 – 10.0.43.190	10.0.43.190
64	10.0.43.191/32	10.0.43.191 – 10.0.43.191	10.0.43.191
65	10.0.43.192/32	10.0.43.192 – 10.0.43.192	10.0.43.192
66	10.0.43.193/32	10.0.43.193 – 10.0.43.193	10.0.43.193
67	10.0.43.194/32	10.0.43.194 – 10.0.43.194	10.0.43.194
68	10.0.43.195/32	10.0.43.195 – 10.0.43.195	10.0.43.195
69	10.0.43.196/32	10.0.43.196 – 10.0.43.196	10.0.43.196
70	10.0.43.197/32	10.0.43.197 – 10.0.43.197	10.0.43.197
71	10.0.43.198/32	10.0.43.198 – 10.0.43.198	10.0.43.198
72	10.0.43.199/32	10.0.43.199 – 10.0.43.199	10.0.43.199
73	10.0.43.200/32	10.0.43.200 – 10.0.43.200	10.0.43.200
74	10.0.43.201/32	10.0.43.201 – 10.0.43.201	10.0.43.201
75	10.0.43.202/32	10.0.43.202 – 10.0.43.202	10.0.43.202
76	10.0.43.203/32	10.0.43.203 – 10.0.43.203	10.0.43.203
77	10.0.43.204/32	10.0.43.204 – 10.0.43.204	10.0.43.204
78	10.0.43.205/32	10.0.43.205 – 10.0.43.205	10.0.43.205
79	10.0.43.206/32	10.0.43.206 – 10.0.43.206	10.0.43.206
80	10.0.43.207/32	10.0.43.207 – 10.0.43.207	10.0.43.207
81	10.0.43.208/32	10.0.43.208 – 10.0.43.208	10.0.43.208
82	10.0.43.209/32	10.0.43.209 – 10.0.43.209	10.0.43.209
83	10.0.43.210/32	10.0.43.210 – 10.0.43.210	10.0.43.210
84	10.0.43.211/32	10.0.43.211 – 10.0.43.211	10.0.43.211
85	10.0.43.212/32	10.0.43.212 – 10.0.43.212	10.0.43.212
86	10.0.43.213/32	10.0.43.213 – 10.0.43.213	10.0.43.213
87	10.0.43.214/32	10.0.43.214 – 10.0.43.214	10.0.43.214
88	10.0.43.215/32	10.0.43.215 – 10.0.43.215	10.0.43.215
89	10.0.43.216/32	10.0.43.216 – 10.0.43.216	10.0.43.216
90	10.0.43.217/32	10.0.43.217 – 10.0.43.217	10.0.43.217
91	10.0.43.218/32	10.0.43.218 – 10.0.43.218	10.0.43.218
92	10.0.43.219/32	10.0.43.219 – 10.0.43.219	10.0.43.219
93	10.0.43.220/32	10.0.43.220 – 10.0.43.220	10.0.43.220
94	10.0.43.221/32	10.0.43.221 – 10.0.43.221	10.0.43.221
95	10.0.43.222/32	10.0.43.222 – 10.0.43.222	10.0.43.222
96	10.0.43.223/32	10.0.43.223 – 10.0.43.223	10.0.43.223
97	10.0.43.224/32	10.0.43.224 – 10.0.43.224	10.0.43.224
98	10.0.43.225/32	10.0.43.225 – 10.0.43.225	10.0.43.225
99	10.0.43.226/32	10.0.43.226 – 10.0.43.226	10.0.43.226
100	10.0.43.227/32	10.0.43.227 – 10.0.43.227	10.0.43.227
101	10.0.43.228/32	10.0.43.228 – 10.0.43.228	10.0.43.228
102	10.0.43.229/32	10.0.43.229 – 10.0.43.229	10.0.43.229
103	10.0.43.230/32	10.0.43.230 – 10.0.43.230	10.0.43.230
104	10.0.43.231/32	10.0.43.231 – 10.0.43.231	10.0.43.231
105	10.0.43.232/32	10.0.43.232 – 10.0.43.232	10.0.43.232
106	10.0.43.233/32	10.0.43.233 – 10.0.43.233	10.0.43.233
107	10.0.43.234/32	10.0.43.234 – 10.0.43.234	10.0.43.234
108	10.0.43.235/32	10.0.43.235 – 10.0.43.235	10.0.43.235
109	10.0.43.236/32	10.0.43.236 – 10.0.43.236	10.0.43.236
110	10.0.43.237/32	10.0.43.237 – 10.0.43.237	10.0.43.237
111	10.0.43.238/32	10.0.43.238 – 10.0.43.238	10.0.43.238
112	10.0.43.239/32	10.0.43.239 – 10.0.43.239	10.0.43.239
113	10.0.43.240/32	10.0.43.240 – 10.0.43.240	10.0.43.240
114	10.0.43.241/32	10.0.43.241 – 10.0.43.241	10.0.43.241
115	10.0.43.242/32	10.0.43.242 – 10.0.43.242	10.0.43.242
116	10.0.43.243/32	10.0.43.243 – 10.0.43.243	10.0.43.243
117	10.0.43.244/32	10.0.43.244 – 10.0.43.244	10.0.43.244
118	10.0.43.245/32	10.0.43.245 – 10.0.43.245	10.0.43.245
119	10.0.43.246/32	10.0.43.246 – 10.0.43.246	10.0.43.246
120	10.0.43.247/32	10.0.43.247 – 10.0.43.247	10.0.43.247
121	10.0.43.248/32	10.0.43.248 – 10.0.43.248	10.0.43.248
122	10.0.43.249/32	10.0.43.249 – 10.0.43.249	10.0.43.249
123	10.0.43.250/32	10.0.43.250 – 10.0.43.250	10.0.43.250
124	10.0.43.251/32	10.0.43.251 – 10.0.43.251	10.0.43.251
125	10.0.43.252/32	10.0.43.252 – 10.0.43.252	10.0.43.252
126	10.0.43.253/32	10.0.43.253 – 10.0.43.253	10.0.43.253
127	10.0.43.254/32	10.0.43.254 – 10.0.43.254	10.0.43.254
128	10.0.43.255/32	10.0.43.255 – 10.0.43.255	10.0.43.255

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 →