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)10.243.78.0/23

network10.243.78.0/23

broadcast10.243.79.255

first host10.243.78.1

last host10.243.79.254

subnet mask255.255.254.0

wildcard0.0.1.255

addresses512

usable hosts510

classA

ipcalc 10.243.78.0/23

address00001010.11110011.01001110.00000000

subnet mask11111111.11111111.11111110.00000000

network00001010.11110011.01001110.00000000

broadcast00001010.11110011.01001111.11111111

green = network part, grey = host part

hex0x0af34e00

decimal183717376

reverse dns0.78.243.10.in-addr.arpa

ipv4-mapped::ffff:af3:4e00

/23 split into /30 · 128 subnets

close ×

#	network	host range	broadcast
1	10.243.78.0/30	10.243.78.1 – 10.243.78.2	10.243.78.3
2	10.243.78.4/30	10.243.78.5 – 10.243.78.6	10.243.78.7
3	10.243.78.8/30	10.243.78.9 – 10.243.78.10	10.243.78.11
4	10.243.78.12/30	10.243.78.13 – 10.243.78.14	10.243.78.15
5	10.243.78.16/30	10.243.78.17 – 10.243.78.18	10.243.78.19
6	10.243.78.20/30	10.243.78.21 – 10.243.78.22	10.243.78.23
7	10.243.78.24/30	10.243.78.25 – 10.243.78.26	10.243.78.27
8	10.243.78.28/30	10.243.78.29 – 10.243.78.30	10.243.78.31
9	10.243.78.32/30	10.243.78.33 – 10.243.78.34	10.243.78.35
10	10.243.78.36/30	10.243.78.37 – 10.243.78.38	10.243.78.39
11	10.243.78.40/30	10.243.78.41 – 10.243.78.42	10.243.78.43
12	10.243.78.44/30	10.243.78.45 – 10.243.78.46	10.243.78.47
13	10.243.78.48/30	10.243.78.49 – 10.243.78.50	10.243.78.51
14	10.243.78.52/30	10.243.78.53 – 10.243.78.54	10.243.78.55
15	10.243.78.56/30	10.243.78.57 – 10.243.78.58	10.243.78.59
16	10.243.78.60/30	10.243.78.61 – 10.243.78.62	10.243.78.63
17	10.243.78.64/30	10.243.78.65 – 10.243.78.66	10.243.78.67
18	10.243.78.68/30	10.243.78.69 – 10.243.78.70	10.243.78.71
19	10.243.78.72/30	10.243.78.73 – 10.243.78.74	10.243.78.75
20	10.243.78.76/30	10.243.78.77 – 10.243.78.78	10.243.78.79
21	10.243.78.80/30	10.243.78.81 – 10.243.78.82	10.243.78.83
22	10.243.78.84/30	10.243.78.85 – 10.243.78.86	10.243.78.87
23	10.243.78.88/30	10.243.78.89 – 10.243.78.90	10.243.78.91
24	10.243.78.92/30	10.243.78.93 – 10.243.78.94	10.243.78.95
25	10.243.78.96/30	10.243.78.97 – 10.243.78.98	10.243.78.99
26	10.243.78.100/30	10.243.78.101 – 10.243.78.102	10.243.78.103
27	10.243.78.104/30	10.243.78.105 – 10.243.78.106	10.243.78.107
28	10.243.78.108/30	10.243.78.109 – 10.243.78.110	10.243.78.111
29	10.243.78.112/30	10.243.78.113 – 10.243.78.114	10.243.78.115
30	10.243.78.116/30	10.243.78.117 – 10.243.78.118	10.243.78.119
31	10.243.78.120/30	10.243.78.121 – 10.243.78.122	10.243.78.123
32	10.243.78.124/30	10.243.78.125 – 10.243.78.126	10.243.78.127
33	10.243.78.128/30	10.243.78.129 – 10.243.78.130	10.243.78.131
34	10.243.78.132/30	10.243.78.133 – 10.243.78.134	10.243.78.135
35	10.243.78.136/30	10.243.78.137 – 10.243.78.138	10.243.78.139
36	10.243.78.140/30	10.243.78.141 – 10.243.78.142	10.243.78.143
37	10.243.78.144/30	10.243.78.145 – 10.243.78.146	10.243.78.147
38	10.243.78.148/30	10.243.78.149 – 10.243.78.150	10.243.78.151
39	10.243.78.152/30	10.243.78.153 – 10.243.78.154	10.243.78.155
40	10.243.78.156/30	10.243.78.157 – 10.243.78.158	10.243.78.159
41	10.243.78.160/30	10.243.78.161 – 10.243.78.162	10.243.78.163
42	10.243.78.164/30	10.243.78.165 – 10.243.78.166	10.243.78.167
43	10.243.78.168/30	10.243.78.169 – 10.243.78.170	10.243.78.171
44	10.243.78.172/30	10.243.78.173 – 10.243.78.174	10.243.78.175
45	10.243.78.176/30	10.243.78.177 – 10.243.78.178	10.243.78.179
46	10.243.78.180/30	10.243.78.181 – 10.243.78.182	10.243.78.183
47	10.243.78.184/30	10.243.78.185 – 10.243.78.186	10.243.78.187
48	10.243.78.188/30	10.243.78.189 – 10.243.78.190	10.243.78.191
49	10.243.78.192/30	10.243.78.193 – 10.243.78.194	10.243.78.195
50	10.243.78.196/30	10.243.78.197 – 10.243.78.198	10.243.78.199
51	10.243.78.200/30	10.243.78.201 – 10.243.78.202	10.243.78.203
52	10.243.78.204/30	10.243.78.205 – 10.243.78.206	10.243.78.207
53	10.243.78.208/30	10.243.78.209 – 10.243.78.210	10.243.78.211
54	10.243.78.212/30	10.243.78.213 – 10.243.78.214	10.243.78.215
55	10.243.78.216/30	10.243.78.217 – 10.243.78.218	10.243.78.219
56	10.243.78.220/30	10.243.78.221 – 10.243.78.222	10.243.78.223
57	10.243.78.224/30	10.243.78.225 – 10.243.78.226	10.243.78.227
58	10.243.78.228/30	10.243.78.229 – 10.243.78.230	10.243.78.231
59	10.243.78.232/30	10.243.78.233 – 10.243.78.234	10.243.78.235
60	10.243.78.236/30	10.243.78.237 – 10.243.78.238	10.243.78.239
61	10.243.78.240/30	10.243.78.241 – 10.243.78.242	10.243.78.243
62	10.243.78.244/30	10.243.78.245 – 10.243.78.246	10.243.78.247
63	10.243.78.248/30	10.243.78.249 – 10.243.78.250	10.243.78.251
64	10.243.78.252/30	10.243.78.253 – 10.243.78.254	10.243.78.255
65	10.243.79.0/30	10.243.79.1 – 10.243.79.2	10.243.79.3
66	10.243.79.4/30	10.243.79.5 – 10.243.79.6	10.243.79.7
67	10.243.79.8/30	10.243.79.9 – 10.243.79.10	10.243.79.11
68	10.243.79.12/30	10.243.79.13 – 10.243.79.14	10.243.79.15
69	10.243.79.16/30	10.243.79.17 – 10.243.79.18	10.243.79.19
70	10.243.79.20/30	10.243.79.21 – 10.243.79.22	10.243.79.23
71	10.243.79.24/30	10.243.79.25 – 10.243.79.26	10.243.79.27
72	10.243.79.28/30	10.243.79.29 – 10.243.79.30	10.243.79.31
73	10.243.79.32/30	10.243.79.33 – 10.243.79.34	10.243.79.35
74	10.243.79.36/30	10.243.79.37 – 10.243.79.38	10.243.79.39
75	10.243.79.40/30	10.243.79.41 – 10.243.79.42	10.243.79.43
76	10.243.79.44/30	10.243.79.45 – 10.243.79.46	10.243.79.47
77	10.243.79.48/30	10.243.79.49 – 10.243.79.50	10.243.79.51
78	10.243.79.52/30	10.243.79.53 – 10.243.79.54	10.243.79.55
79	10.243.79.56/30	10.243.79.57 – 10.243.79.58	10.243.79.59
80	10.243.79.60/30	10.243.79.61 – 10.243.79.62	10.243.79.63
81	10.243.79.64/30	10.243.79.65 – 10.243.79.66	10.243.79.67
82	10.243.79.68/30	10.243.79.69 – 10.243.79.70	10.243.79.71
83	10.243.79.72/30	10.243.79.73 – 10.243.79.74	10.243.79.75
84	10.243.79.76/30	10.243.79.77 – 10.243.79.78	10.243.79.79
85	10.243.79.80/30	10.243.79.81 – 10.243.79.82	10.243.79.83
86	10.243.79.84/30	10.243.79.85 – 10.243.79.86	10.243.79.87
87	10.243.79.88/30	10.243.79.89 – 10.243.79.90	10.243.79.91
88	10.243.79.92/30	10.243.79.93 – 10.243.79.94	10.243.79.95
89	10.243.79.96/30	10.243.79.97 – 10.243.79.98	10.243.79.99
90	10.243.79.100/30	10.243.79.101 – 10.243.79.102	10.243.79.103
91	10.243.79.104/30	10.243.79.105 – 10.243.79.106	10.243.79.107
92	10.243.79.108/30	10.243.79.109 – 10.243.79.110	10.243.79.111
93	10.243.79.112/30	10.243.79.113 – 10.243.79.114	10.243.79.115
94	10.243.79.116/30	10.243.79.117 – 10.243.79.118	10.243.79.119
95	10.243.79.120/30	10.243.79.121 – 10.243.79.122	10.243.79.123
96	10.243.79.124/30	10.243.79.125 – 10.243.79.126	10.243.79.127
97	10.243.79.128/30	10.243.79.129 – 10.243.79.130	10.243.79.131
98	10.243.79.132/30	10.243.79.133 – 10.243.79.134	10.243.79.135
99	10.243.79.136/30	10.243.79.137 – 10.243.79.138	10.243.79.139
100	10.243.79.140/30	10.243.79.141 – 10.243.79.142	10.243.79.143
101	10.243.79.144/30	10.243.79.145 – 10.243.79.146	10.243.79.147
102	10.243.79.148/30	10.243.79.149 – 10.243.79.150	10.243.79.151
103	10.243.79.152/30	10.243.79.153 – 10.243.79.154	10.243.79.155
104	10.243.79.156/30	10.243.79.157 – 10.243.79.158	10.243.79.159
105	10.243.79.160/30	10.243.79.161 – 10.243.79.162	10.243.79.163
106	10.243.79.164/30	10.243.79.165 – 10.243.79.166	10.243.79.167
107	10.243.79.168/30	10.243.79.169 – 10.243.79.170	10.243.79.171
108	10.243.79.172/30	10.243.79.173 – 10.243.79.174	10.243.79.175
109	10.243.79.176/30	10.243.79.177 – 10.243.79.178	10.243.79.179
110	10.243.79.180/30	10.243.79.181 – 10.243.79.182	10.243.79.183
111	10.243.79.184/30	10.243.79.185 – 10.243.79.186	10.243.79.187
112	10.243.79.188/30	10.243.79.189 – 10.243.79.190	10.243.79.191
113	10.243.79.192/30	10.243.79.193 – 10.243.79.194	10.243.79.195
114	10.243.79.196/30	10.243.79.197 – 10.243.79.198	10.243.79.199
115	10.243.79.200/30	10.243.79.201 – 10.243.79.202	10.243.79.203
116	10.243.79.204/30	10.243.79.205 – 10.243.79.206	10.243.79.207
117	10.243.79.208/30	10.243.79.209 – 10.243.79.210	10.243.79.211
118	10.243.79.212/30	10.243.79.213 – 10.243.79.214	10.243.79.215
119	10.243.79.216/30	10.243.79.217 – 10.243.79.218	10.243.79.219
120	10.243.79.220/30	10.243.79.221 – 10.243.79.222	10.243.79.223
121	10.243.79.224/30	10.243.79.225 – 10.243.79.226	10.243.79.227
122	10.243.79.228/30	10.243.79.229 – 10.243.79.230	10.243.79.231
123	10.243.79.232/30	10.243.79.233 – 10.243.79.234	10.243.79.235
124	10.243.79.236/30	10.243.79.237 – 10.243.79.238	10.243.79.239
125	10.243.79.240/30	10.243.79.241 – 10.243.79.242	10.243.79.243
126	10.243.79.244/30	10.243.79.245 – 10.243.79.246	10.243.79.247
127	10.243.79.248/30	10.243.79.249 – 10.243.79.250	10.243.79.251
128	10.243.79.252/30	10.243.79.253 – 10.243.79.254	10.243.79.255

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 /23
/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	1
/24	255.255.255.0	256	254	2 split →
/25	255.255.255.128	128	126	4 split →
/26	255.255.255.192	64	62	8 split →
/27	255.255.255.224	32	30	16 split →
/28	255.255.255.240	16	14	32 split →
/29	255.255.255.248	8	6	64 split →
/30	255.255.255.252	4	2	128 split →
/31	255.255.255.254	2	2	256 split →
/32	255.255.255.255	1	1	512 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 →