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)10.3.243.0/24

network10.3.243.0/24

broadcast10.3.243.255

first host10.3.243.1

last host10.3.243.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.3.243.0/24

address00001010.00000011.11110011.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.00000011.11110011.00000000

broadcast00001010.00000011.11110011.11111111

green = network part, grey = host part

hex0x0a03f300

decimal168030976

reverse dns0.243.3.10.in-addr.arpa

ipv4-mapped::ffff:a03:f300

/24 split into /31 · 128 subnets

close ×

#	network	host range	broadcast
1	10.3.243.0/31	10.3.243.0 – 10.3.243.1	10.3.243.1
2	10.3.243.2/31	10.3.243.2 – 10.3.243.3	10.3.243.3
3	10.3.243.4/31	10.3.243.4 – 10.3.243.5	10.3.243.5
4	10.3.243.6/31	10.3.243.6 – 10.3.243.7	10.3.243.7
5	10.3.243.8/31	10.3.243.8 – 10.3.243.9	10.3.243.9
6	10.3.243.10/31	10.3.243.10 – 10.3.243.11	10.3.243.11
7	10.3.243.12/31	10.3.243.12 – 10.3.243.13	10.3.243.13
8	10.3.243.14/31	10.3.243.14 – 10.3.243.15	10.3.243.15
9	10.3.243.16/31	10.3.243.16 – 10.3.243.17	10.3.243.17
10	10.3.243.18/31	10.3.243.18 – 10.3.243.19	10.3.243.19
11	10.3.243.20/31	10.3.243.20 – 10.3.243.21	10.3.243.21
12	10.3.243.22/31	10.3.243.22 – 10.3.243.23	10.3.243.23
13	10.3.243.24/31	10.3.243.24 – 10.3.243.25	10.3.243.25
14	10.3.243.26/31	10.3.243.26 – 10.3.243.27	10.3.243.27
15	10.3.243.28/31	10.3.243.28 – 10.3.243.29	10.3.243.29
16	10.3.243.30/31	10.3.243.30 – 10.3.243.31	10.3.243.31
17	10.3.243.32/31	10.3.243.32 – 10.3.243.33	10.3.243.33
18	10.3.243.34/31	10.3.243.34 – 10.3.243.35	10.3.243.35
19	10.3.243.36/31	10.3.243.36 – 10.3.243.37	10.3.243.37
20	10.3.243.38/31	10.3.243.38 – 10.3.243.39	10.3.243.39
21	10.3.243.40/31	10.3.243.40 – 10.3.243.41	10.3.243.41
22	10.3.243.42/31	10.3.243.42 – 10.3.243.43	10.3.243.43
23	10.3.243.44/31	10.3.243.44 – 10.3.243.45	10.3.243.45
24	10.3.243.46/31	10.3.243.46 – 10.3.243.47	10.3.243.47
25	10.3.243.48/31	10.3.243.48 – 10.3.243.49	10.3.243.49
26	10.3.243.50/31	10.3.243.50 – 10.3.243.51	10.3.243.51
27	10.3.243.52/31	10.3.243.52 – 10.3.243.53	10.3.243.53
28	10.3.243.54/31	10.3.243.54 – 10.3.243.55	10.3.243.55
29	10.3.243.56/31	10.3.243.56 – 10.3.243.57	10.3.243.57
30	10.3.243.58/31	10.3.243.58 – 10.3.243.59	10.3.243.59
31	10.3.243.60/31	10.3.243.60 – 10.3.243.61	10.3.243.61
32	10.3.243.62/31	10.3.243.62 – 10.3.243.63	10.3.243.63
33	10.3.243.64/31	10.3.243.64 – 10.3.243.65	10.3.243.65
34	10.3.243.66/31	10.3.243.66 – 10.3.243.67	10.3.243.67
35	10.3.243.68/31	10.3.243.68 – 10.3.243.69	10.3.243.69
36	10.3.243.70/31	10.3.243.70 – 10.3.243.71	10.3.243.71
37	10.3.243.72/31	10.3.243.72 – 10.3.243.73	10.3.243.73
38	10.3.243.74/31	10.3.243.74 – 10.3.243.75	10.3.243.75
39	10.3.243.76/31	10.3.243.76 – 10.3.243.77	10.3.243.77
40	10.3.243.78/31	10.3.243.78 – 10.3.243.79	10.3.243.79
41	10.3.243.80/31	10.3.243.80 – 10.3.243.81	10.3.243.81
42	10.3.243.82/31	10.3.243.82 – 10.3.243.83	10.3.243.83
43	10.3.243.84/31	10.3.243.84 – 10.3.243.85	10.3.243.85
44	10.3.243.86/31	10.3.243.86 – 10.3.243.87	10.3.243.87
45	10.3.243.88/31	10.3.243.88 – 10.3.243.89	10.3.243.89
46	10.3.243.90/31	10.3.243.90 – 10.3.243.91	10.3.243.91
47	10.3.243.92/31	10.3.243.92 – 10.3.243.93	10.3.243.93
48	10.3.243.94/31	10.3.243.94 – 10.3.243.95	10.3.243.95
49	10.3.243.96/31	10.3.243.96 – 10.3.243.97	10.3.243.97
50	10.3.243.98/31	10.3.243.98 – 10.3.243.99	10.3.243.99
51	10.3.243.100/31	10.3.243.100 – 10.3.243.101	10.3.243.101
52	10.3.243.102/31	10.3.243.102 – 10.3.243.103	10.3.243.103
53	10.3.243.104/31	10.3.243.104 – 10.3.243.105	10.3.243.105
54	10.3.243.106/31	10.3.243.106 – 10.3.243.107	10.3.243.107
55	10.3.243.108/31	10.3.243.108 – 10.3.243.109	10.3.243.109
56	10.3.243.110/31	10.3.243.110 – 10.3.243.111	10.3.243.111
57	10.3.243.112/31	10.3.243.112 – 10.3.243.113	10.3.243.113
58	10.3.243.114/31	10.3.243.114 – 10.3.243.115	10.3.243.115
59	10.3.243.116/31	10.3.243.116 – 10.3.243.117	10.3.243.117
60	10.3.243.118/31	10.3.243.118 – 10.3.243.119	10.3.243.119
61	10.3.243.120/31	10.3.243.120 – 10.3.243.121	10.3.243.121
62	10.3.243.122/31	10.3.243.122 – 10.3.243.123	10.3.243.123
63	10.3.243.124/31	10.3.243.124 – 10.3.243.125	10.3.243.125
64	10.3.243.126/31	10.3.243.126 – 10.3.243.127	10.3.243.127
65	10.3.243.128/31	10.3.243.128 – 10.3.243.129	10.3.243.129
66	10.3.243.130/31	10.3.243.130 – 10.3.243.131	10.3.243.131
67	10.3.243.132/31	10.3.243.132 – 10.3.243.133	10.3.243.133
68	10.3.243.134/31	10.3.243.134 – 10.3.243.135	10.3.243.135
69	10.3.243.136/31	10.3.243.136 – 10.3.243.137	10.3.243.137
70	10.3.243.138/31	10.3.243.138 – 10.3.243.139	10.3.243.139
71	10.3.243.140/31	10.3.243.140 – 10.3.243.141	10.3.243.141
72	10.3.243.142/31	10.3.243.142 – 10.3.243.143	10.3.243.143
73	10.3.243.144/31	10.3.243.144 – 10.3.243.145	10.3.243.145
74	10.3.243.146/31	10.3.243.146 – 10.3.243.147	10.3.243.147
75	10.3.243.148/31	10.3.243.148 – 10.3.243.149	10.3.243.149
76	10.3.243.150/31	10.3.243.150 – 10.3.243.151	10.3.243.151
77	10.3.243.152/31	10.3.243.152 – 10.3.243.153	10.3.243.153
78	10.3.243.154/31	10.3.243.154 – 10.3.243.155	10.3.243.155
79	10.3.243.156/31	10.3.243.156 – 10.3.243.157	10.3.243.157
80	10.3.243.158/31	10.3.243.158 – 10.3.243.159	10.3.243.159
81	10.3.243.160/31	10.3.243.160 – 10.3.243.161	10.3.243.161
82	10.3.243.162/31	10.3.243.162 – 10.3.243.163	10.3.243.163
83	10.3.243.164/31	10.3.243.164 – 10.3.243.165	10.3.243.165
84	10.3.243.166/31	10.3.243.166 – 10.3.243.167	10.3.243.167
85	10.3.243.168/31	10.3.243.168 – 10.3.243.169	10.3.243.169
86	10.3.243.170/31	10.3.243.170 – 10.3.243.171	10.3.243.171
87	10.3.243.172/31	10.3.243.172 – 10.3.243.173	10.3.243.173
88	10.3.243.174/31	10.3.243.174 – 10.3.243.175	10.3.243.175
89	10.3.243.176/31	10.3.243.176 – 10.3.243.177	10.3.243.177
90	10.3.243.178/31	10.3.243.178 – 10.3.243.179	10.3.243.179
91	10.3.243.180/31	10.3.243.180 – 10.3.243.181	10.3.243.181
92	10.3.243.182/31	10.3.243.182 – 10.3.243.183	10.3.243.183
93	10.3.243.184/31	10.3.243.184 – 10.3.243.185	10.3.243.185
94	10.3.243.186/31	10.3.243.186 – 10.3.243.187	10.3.243.187
95	10.3.243.188/31	10.3.243.188 – 10.3.243.189	10.3.243.189
96	10.3.243.190/31	10.3.243.190 – 10.3.243.191	10.3.243.191
97	10.3.243.192/31	10.3.243.192 – 10.3.243.193	10.3.243.193
98	10.3.243.194/31	10.3.243.194 – 10.3.243.195	10.3.243.195
99	10.3.243.196/31	10.3.243.196 – 10.3.243.197	10.3.243.197
100	10.3.243.198/31	10.3.243.198 – 10.3.243.199	10.3.243.199
101	10.3.243.200/31	10.3.243.200 – 10.3.243.201	10.3.243.201
102	10.3.243.202/31	10.3.243.202 – 10.3.243.203	10.3.243.203
103	10.3.243.204/31	10.3.243.204 – 10.3.243.205	10.3.243.205
104	10.3.243.206/31	10.3.243.206 – 10.3.243.207	10.3.243.207
105	10.3.243.208/31	10.3.243.208 – 10.3.243.209	10.3.243.209
106	10.3.243.210/31	10.3.243.210 – 10.3.243.211	10.3.243.211
107	10.3.243.212/31	10.3.243.212 – 10.3.243.213	10.3.243.213
108	10.3.243.214/31	10.3.243.214 – 10.3.243.215	10.3.243.215
109	10.3.243.216/31	10.3.243.216 – 10.3.243.217	10.3.243.217
110	10.3.243.218/31	10.3.243.218 – 10.3.243.219	10.3.243.219
111	10.3.243.220/31	10.3.243.220 – 10.3.243.221	10.3.243.221
112	10.3.243.222/31	10.3.243.222 – 10.3.243.223	10.3.243.223
113	10.3.243.224/31	10.3.243.224 – 10.3.243.225	10.3.243.225
114	10.3.243.226/31	10.3.243.226 – 10.3.243.227	10.3.243.227
115	10.3.243.228/31	10.3.243.228 – 10.3.243.229	10.3.243.229
116	10.3.243.230/31	10.3.243.230 – 10.3.243.231	10.3.243.231
117	10.3.243.232/31	10.3.243.232 – 10.3.243.233	10.3.243.233
118	10.3.243.234/31	10.3.243.234 – 10.3.243.235	10.3.243.235
119	10.3.243.236/31	10.3.243.236 – 10.3.243.237	10.3.243.237
120	10.3.243.238/31	10.3.243.238 – 10.3.243.239	10.3.243.239
121	10.3.243.240/31	10.3.243.240 – 10.3.243.241	10.3.243.241
122	10.3.243.242/31	10.3.243.242 – 10.3.243.243	10.3.243.243
123	10.3.243.244/31	10.3.243.244 – 10.3.243.245	10.3.243.245
124	10.3.243.246/31	10.3.243.246 – 10.3.243.247	10.3.243.247
125	10.3.243.248/31	10.3.243.248 – 10.3.243.249	10.3.243.249
126	10.3.243.250/31	10.3.243.250 – 10.3.243.251	10.3.243.251
127	10.3.243.252/31	10.3.243.252 – 10.3.243.253	10.3.243.253
128	10.3.243.254/31	10.3.243.254 – 10.3.243.255	10.3.243.255

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 →