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)10.2.1.128/26

network10.2.1.128/26

broadcast10.2.1.191

first host10.2.1.129

last host10.2.1.190

subnet mask255.255.255.192

wildcard0.0.0.63

addresses64

usable hosts62

classA

ipcalc 10.2.1.128/26

address00001010.00000010.00000001.10000000

subnet mask11111111.11111111.11111111.11000000

network00001010.00000010.00000001.10000000

broadcast00001010.00000010.00000001.10111111

green = network part, grey = host part

hex0x0a020180

decimal167903616

reverse dns128.1.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:180

/26 split into /32 · 64 subnets

close ×

#	network	host range	broadcast
1	10.2.1.128/32	10.2.1.128 – 10.2.1.128	10.2.1.128
2	10.2.1.129/32	10.2.1.129 – 10.2.1.129	10.2.1.129
3	10.2.1.130/32	10.2.1.130 – 10.2.1.130	10.2.1.130
4	10.2.1.131/32	10.2.1.131 – 10.2.1.131	10.2.1.131
5	10.2.1.132/32	10.2.1.132 – 10.2.1.132	10.2.1.132
6	10.2.1.133/32	10.2.1.133 – 10.2.1.133	10.2.1.133
7	10.2.1.134/32	10.2.1.134 – 10.2.1.134	10.2.1.134
8	10.2.1.135/32	10.2.1.135 – 10.2.1.135	10.2.1.135
9	10.2.1.136/32	10.2.1.136 – 10.2.1.136	10.2.1.136
10	10.2.1.137/32	10.2.1.137 – 10.2.1.137	10.2.1.137
11	10.2.1.138/32	10.2.1.138 – 10.2.1.138	10.2.1.138
12	10.2.1.139/32	10.2.1.139 – 10.2.1.139	10.2.1.139
13	10.2.1.140/32	10.2.1.140 – 10.2.1.140	10.2.1.140
14	10.2.1.141/32	10.2.1.141 – 10.2.1.141	10.2.1.141
15	10.2.1.142/32	10.2.1.142 – 10.2.1.142	10.2.1.142
16	10.2.1.143/32	10.2.1.143 – 10.2.1.143	10.2.1.143
17	10.2.1.144/32	10.2.1.144 – 10.2.1.144	10.2.1.144
18	10.2.1.145/32	10.2.1.145 – 10.2.1.145	10.2.1.145
19	10.2.1.146/32	10.2.1.146 – 10.2.1.146	10.2.1.146
20	10.2.1.147/32	10.2.1.147 – 10.2.1.147	10.2.1.147
21	10.2.1.148/32	10.2.1.148 – 10.2.1.148	10.2.1.148
22	10.2.1.149/32	10.2.1.149 – 10.2.1.149	10.2.1.149
23	10.2.1.150/32	10.2.1.150 – 10.2.1.150	10.2.1.150
24	10.2.1.151/32	10.2.1.151 – 10.2.1.151	10.2.1.151
25	10.2.1.152/32	10.2.1.152 – 10.2.1.152	10.2.1.152
26	10.2.1.153/32	10.2.1.153 – 10.2.1.153	10.2.1.153
27	10.2.1.154/32	10.2.1.154 – 10.2.1.154	10.2.1.154
28	10.2.1.155/32	10.2.1.155 – 10.2.1.155	10.2.1.155
29	10.2.1.156/32	10.2.1.156 – 10.2.1.156	10.2.1.156
30	10.2.1.157/32	10.2.1.157 – 10.2.1.157	10.2.1.157
31	10.2.1.158/32	10.2.1.158 – 10.2.1.158	10.2.1.158
32	10.2.1.159/32	10.2.1.159 – 10.2.1.159	10.2.1.159
33	10.2.1.160/32	10.2.1.160 – 10.2.1.160	10.2.1.160
34	10.2.1.161/32	10.2.1.161 – 10.2.1.161	10.2.1.161
35	10.2.1.162/32	10.2.1.162 – 10.2.1.162	10.2.1.162
36	10.2.1.163/32	10.2.1.163 – 10.2.1.163	10.2.1.163
37	10.2.1.164/32	10.2.1.164 – 10.2.1.164	10.2.1.164
38	10.2.1.165/32	10.2.1.165 – 10.2.1.165	10.2.1.165
39	10.2.1.166/32	10.2.1.166 – 10.2.1.166	10.2.1.166
40	10.2.1.167/32	10.2.1.167 – 10.2.1.167	10.2.1.167
41	10.2.1.168/32	10.2.1.168 – 10.2.1.168	10.2.1.168
42	10.2.1.169/32	10.2.1.169 – 10.2.1.169	10.2.1.169
43	10.2.1.170/32	10.2.1.170 – 10.2.1.170	10.2.1.170
44	10.2.1.171/32	10.2.1.171 – 10.2.1.171	10.2.1.171
45	10.2.1.172/32	10.2.1.172 – 10.2.1.172	10.2.1.172
46	10.2.1.173/32	10.2.1.173 – 10.2.1.173	10.2.1.173
47	10.2.1.174/32	10.2.1.174 – 10.2.1.174	10.2.1.174
48	10.2.1.175/32	10.2.1.175 – 10.2.1.175	10.2.1.175
49	10.2.1.176/32	10.2.1.176 – 10.2.1.176	10.2.1.176
50	10.2.1.177/32	10.2.1.177 – 10.2.1.177	10.2.1.177
51	10.2.1.178/32	10.2.1.178 – 10.2.1.178	10.2.1.178
52	10.2.1.179/32	10.2.1.179 – 10.2.1.179	10.2.1.179
53	10.2.1.180/32	10.2.1.180 – 10.2.1.180	10.2.1.180
54	10.2.1.181/32	10.2.1.181 – 10.2.1.181	10.2.1.181
55	10.2.1.182/32	10.2.1.182 – 10.2.1.182	10.2.1.182
56	10.2.1.183/32	10.2.1.183 – 10.2.1.183	10.2.1.183
57	10.2.1.184/32	10.2.1.184 – 10.2.1.184	10.2.1.184
58	10.2.1.185/32	10.2.1.185 – 10.2.1.185	10.2.1.185
59	10.2.1.186/32	10.2.1.186 – 10.2.1.186	10.2.1.186
60	10.2.1.187/32	10.2.1.187 – 10.2.1.187	10.2.1.187
61	10.2.1.188/32	10.2.1.188 – 10.2.1.188	10.2.1.188
62	10.2.1.189/32	10.2.1.189 – 10.2.1.189	10.2.1.189
63	10.2.1.190/32	10.2.1.190 – 10.2.1.190	10.2.1.190
64	10.2.1.191/32	10.2.1.191 – 10.2.1.191	10.2.1.191

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 /26
/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	-
/26	255.255.255.192	64	62	1
/27	255.255.255.224	32	30	2 split →
/28	255.255.255.240	16	14	4 split →
/29	255.255.255.248	8	6	8 split →
/30	255.255.255.252	4	2	16 split →
/31	255.255.255.254	2	2	32 split →
/32	255.255.255.255	1	1	64 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 →