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)10.2.240.0/24

network10.2.240.0/24

broadcast10.2.240.255

first host10.2.240.1

last host10.2.240.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.2.240.0/24

address00001010.00000010.11110000.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.00000010.11110000.00000000

broadcast00001010.00000010.11110000.11111111

green = network part, grey = host part

hex0x0a02f000

decimal167964672

reverse dns0.240.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:f000

/24 split into /31 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.240.0/31	10.2.240.0 – 10.2.240.1	10.2.240.1
2	10.2.240.2/31	10.2.240.2 – 10.2.240.3	10.2.240.3
3	10.2.240.4/31	10.2.240.4 – 10.2.240.5	10.2.240.5
4	10.2.240.6/31	10.2.240.6 – 10.2.240.7	10.2.240.7
5	10.2.240.8/31	10.2.240.8 – 10.2.240.9	10.2.240.9
6	10.2.240.10/31	10.2.240.10 – 10.2.240.11	10.2.240.11
7	10.2.240.12/31	10.2.240.12 – 10.2.240.13	10.2.240.13
8	10.2.240.14/31	10.2.240.14 – 10.2.240.15	10.2.240.15
9	10.2.240.16/31	10.2.240.16 – 10.2.240.17	10.2.240.17
10	10.2.240.18/31	10.2.240.18 – 10.2.240.19	10.2.240.19
11	10.2.240.20/31	10.2.240.20 – 10.2.240.21	10.2.240.21
12	10.2.240.22/31	10.2.240.22 – 10.2.240.23	10.2.240.23
13	10.2.240.24/31	10.2.240.24 – 10.2.240.25	10.2.240.25
14	10.2.240.26/31	10.2.240.26 – 10.2.240.27	10.2.240.27
15	10.2.240.28/31	10.2.240.28 – 10.2.240.29	10.2.240.29
16	10.2.240.30/31	10.2.240.30 – 10.2.240.31	10.2.240.31
17	10.2.240.32/31	10.2.240.32 – 10.2.240.33	10.2.240.33
18	10.2.240.34/31	10.2.240.34 – 10.2.240.35	10.2.240.35
19	10.2.240.36/31	10.2.240.36 – 10.2.240.37	10.2.240.37
20	10.2.240.38/31	10.2.240.38 – 10.2.240.39	10.2.240.39
21	10.2.240.40/31	10.2.240.40 – 10.2.240.41	10.2.240.41
22	10.2.240.42/31	10.2.240.42 – 10.2.240.43	10.2.240.43
23	10.2.240.44/31	10.2.240.44 – 10.2.240.45	10.2.240.45
24	10.2.240.46/31	10.2.240.46 – 10.2.240.47	10.2.240.47
25	10.2.240.48/31	10.2.240.48 – 10.2.240.49	10.2.240.49
26	10.2.240.50/31	10.2.240.50 – 10.2.240.51	10.2.240.51
27	10.2.240.52/31	10.2.240.52 – 10.2.240.53	10.2.240.53
28	10.2.240.54/31	10.2.240.54 – 10.2.240.55	10.2.240.55
29	10.2.240.56/31	10.2.240.56 – 10.2.240.57	10.2.240.57
30	10.2.240.58/31	10.2.240.58 – 10.2.240.59	10.2.240.59
31	10.2.240.60/31	10.2.240.60 – 10.2.240.61	10.2.240.61
32	10.2.240.62/31	10.2.240.62 – 10.2.240.63	10.2.240.63
33	10.2.240.64/31	10.2.240.64 – 10.2.240.65	10.2.240.65
34	10.2.240.66/31	10.2.240.66 – 10.2.240.67	10.2.240.67
35	10.2.240.68/31	10.2.240.68 – 10.2.240.69	10.2.240.69
36	10.2.240.70/31	10.2.240.70 – 10.2.240.71	10.2.240.71
37	10.2.240.72/31	10.2.240.72 – 10.2.240.73	10.2.240.73
38	10.2.240.74/31	10.2.240.74 – 10.2.240.75	10.2.240.75
39	10.2.240.76/31	10.2.240.76 – 10.2.240.77	10.2.240.77
40	10.2.240.78/31	10.2.240.78 – 10.2.240.79	10.2.240.79
41	10.2.240.80/31	10.2.240.80 – 10.2.240.81	10.2.240.81
42	10.2.240.82/31	10.2.240.82 – 10.2.240.83	10.2.240.83
43	10.2.240.84/31	10.2.240.84 – 10.2.240.85	10.2.240.85
44	10.2.240.86/31	10.2.240.86 – 10.2.240.87	10.2.240.87
45	10.2.240.88/31	10.2.240.88 – 10.2.240.89	10.2.240.89
46	10.2.240.90/31	10.2.240.90 – 10.2.240.91	10.2.240.91
47	10.2.240.92/31	10.2.240.92 – 10.2.240.93	10.2.240.93
48	10.2.240.94/31	10.2.240.94 – 10.2.240.95	10.2.240.95
49	10.2.240.96/31	10.2.240.96 – 10.2.240.97	10.2.240.97
50	10.2.240.98/31	10.2.240.98 – 10.2.240.99	10.2.240.99
51	10.2.240.100/31	10.2.240.100 – 10.2.240.101	10.2.240.101
52	10.2.240.102/31	10.2.240.102 – 10.2.240.103	10.2.240.103
53	10.2.240.104/31	10.2.240.104 – 10.2.240.105	10.2.240.105
54	10.2.240.106/31	10.2.240.106 – 10.2.240.107	10.2.240.107
55	10.2.240.108/31	10.2.240.108 – 10.2.240.109	10.2.240.109
56	10.2.240.110/31	10.2.240.110 – 10.2.240.111	10.2.240.111
57	10.2.240.112/31	10.2.240.112 – 10.2.240.113	10.2.240.113
58	10.2.240.114/31	10.2.240.114 – 10.2.240.115	10.2.240.115
59	10.2.240.116/31	10.2.240.116 – 10.2.240.117	10.2.240.117
60	10.2.240.118/31	10.2.240.118 – 10.2.240.119	10.2.240.119
61	10.2.240.120/31	10.2.240.120 – 10.2.240.121	10.2.240.121
62	10.2.240.122/31	10.2.240.122 – 10.2.240.123	10.2.240.123
63	10.2.240.124/31	10.2.240.124 – 10.2.240.125	10.2.240.125
64	10.2.240.126/31	10.2.240.126 – 10.2.240.127	10.2.240.127
65	10.2.240.128/31	10.2.240.128 – 10.2.240.129	10.2.240.129
66	10.2.240.130/31	10.2.240.130 – 10.2.240.131	10.2.240.131
67	10.2.240.132/31	10.2.240.132 – 10.2.240.133	10.2.240.133
68	10.2.240.134/31	10.2.240.134 – 10.2.240.135	10.2.240.135
69	10.2.240.136/31	10.2.240.136 – 10.2.240.137	10.2.240.137
70	10.2.240.138/31	10.2.240.138 – 10.2.240.139	10.2.240.139
71	10.2.240.140/31	10.2.240.140 – 10.2.240.141	10.2.240.141
72	10.2.240.142/31	10.2.240.142 – 10.2.240.143	10.2.240.143
73	10.2.240.144/31	10.2.240.144 – 10.2.240.145	10.2.240.145
74	10.2.240.146/31	10.2.240.146 – 10.2.240.147	10.2.240.147
75	10.2.240.148/31	10.2.240.148 – 10.2.240.149	10.2.240.149
76	10.2.240.150/31	10.2.240.150 – 10.2.240.151	10.2.240.151
77	10.2.240.152/31	10.2.240.152 – 10.2.240.153	10.2.240.153
78	10.2.240.154/31	10.2.240.154 – 10.2.240.155	10.2.240.155
79	10.2.240.156/31	10.2.240.156 – 10.2.240.157	10.2.240.157
80	10.2.240.158/31	10.2.240.158 – 10.2.240.159	10.2.240.159
81	10.2.240.160/31	10.2.240.160 – 10.2.240.161	10.2.240.161
82	10.2.240.162/31	10.2.240.162 – 10.2.240.163	10.2.240.163
83	10.2.240.164/31	10.2.240.164 – 10.2.240.165	10.2.240.165
84	10.2.240.166/31	10.2.240.166 – 10.2.240.167	10.2.240.167
85	10.2.240.168/31	10.2.240.168 – 10.2.240.169	10.2.240.169
86	10.2.240.170/31	10.2.240.170 – 10.2.240.171	10.2.240.171
87	10.2.240.172/31	10.2.240.172 – 10.2.240.173	10.2.240.173
88	10.2.240.174/31	10.2.240.174 – 10.2.240.175	10.2.240.175
89	10.2.240.176/31	10.2.240.176 – 10.2.240.177	10.2.240.177
90	10.2.240.178/31	10.2.240.178 – 10.2.240.179	10.2.240.179
91	10.2.240.180/31	10.2.240.180 – 10.2.240.181	10.2.240.181
92	10.2.240.182/31	10.2.240.182 – 10.2.240.183	10.2.240.183
93	10.2.240.184/31	10.2.240.184 – 10.2.240.185	10.2.240.185
94	10.2.240.186/31	10.2.240.186 – 10.2.240.187	10.2.240.187
95	10.2.240.188/31	10.2.240.188 – 10.2.240.189	10.2.240.189
96	10.2.240.190/31	10.2.240.190 – 10.2.240.191	10.2.240.191
97	10.2.240.192/31	10.2.240.192 – 10.2.240.193	10.2.240.193
98	10.2.240.194/31	10.2.240.194 – 10.2.240.195	10.2.240.195
99	10.2.240.196/31	10.2.240.196 – 10.2.240.197	10.2.240.197
100	10.2.240.198/31	10.2.240.198 – 10.2.240.199	10.2.240.199
101	10.2.240.200/31	10.2.240.200 – 10.2.240.201	10.2.240.201
102	10.2.240.202/31	10.2.240.202 – 10.2.240.203	10.2.240.203
103	10.2.240.204/31	10.2.240.204 – 10.2.240.205	10.2.240.205
104	10.2.240.206/31	10.2.240.206 – 10.2.240.207	10.2.240.207
105	10.2.240.208/31	10.2.240.208 – 10.2.240.209	10.2.240.209
106	10.2.240.210/31	10.2.240.210 – 10.2.240.211	10.2.240.211
107	10.2.240.212/31	10.2.240.212 – 10.2.240.213	10.2.240.213
108	10.2.240.214/31	10.2.240.214 – 10.2.240.215	10.2.240.215
109	10.2.240.216/31	10.2.240.216 – 10.2.240.217	10.2.240.217
110	10.2.240.218/31	10.2.240.218 – 10.2.240.219	10.2.240.219
111	10.2.240.220/31	10.2.240.220 – 10.2.240.221	10.2.240.221
112	10.2.240.222/31	10.2.240.222 – 10.2.240.223	10.2.240.223
113	10.2.240.224/31	10.2.240.224 – 10.2.240.225	10.2.240.225
114	10.2.240.226/31	10.2.240.226 – 10.2.240.227	10.2.240.227
115	10.2.240.228/31	10.2.240.228 – 10.2.240.229	10.2.240.229
116	10.2.240.230/31	10.2.240.230 – 10.2.240.231	10.2.240.231
117	10.2.240.232/31	10.2.240.232 – 10.2.240.233	10.2.240.233
118	10.2.240.234/31	10.2.240.234 – 10.2.240.235	10.2.240.235
119	10.2.240.236/31	10.2.240.236 – 10.2.240.237	10.2.240.237
120	10.2.240.238/31	10.2.240.238 – 10.2.240.239	10.2.240.239
121	10.2.240.240/31	10.2.240.240 – 10.2.240.241	10.2.240.241
122	10.2.240.242/31	10.2.240.242 – 10.2.240.243	10.2.240.243
123	10.2.240.244/31	10.2.240.244 – 10.2.240.245	10.2.240.245
124	10.2.240.246/31	10.2.240.246 – 10.2.240.247	10.2.240.247
125	10.2.240.248/31	10.2.240.248 – 10.2.240.249	10.2.240.249
126	10.2.240.250/31	10.2.240.250 – 10.2.240.251	10.2.240.251
127	10.2.240.252/31	10.2.240.252 – 10.2.240.253	10.2.240.253
128	10.2.240.254/31	10.2.240.254 – 10.2.240.255	10.2.240.255

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 /24
/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	1
/25	255.255.255.128	128	126	2 split →
/26	255.255.255.192	64	62	4 split →
/27	255.255.255.224	32	30	8 split →
/28	255.255.255.240	16	14	16 split →
/29	255.255.255.248	8	6	32 split →
/30	255.255.255.252	4	2	64 split →
/31	255.255.255.254	2	2	128 split →
/32	255.255.255.255	1	1	256 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 →