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)10.0.166.0/23

network10.0.166.0/23

broadcast10.0.167.255

first host10.0.166.1

last host10.0.167.254

subnet mask255.255.254.0

wildcard0.0.1.255

addresses512

usable hosts510

classA

ipcalc 10.0.166.0/23

address00001010.00000000.10100110.00000000

subnet mask11111111.11111111.11111110.00000000

network00001010.00000000.10100110.00000000

broadcast00001010.00000000.10100111.11111111

green = network part, grey = host part

hex0x0a00a600

decimal167814656

reverse dns0.166.0.10.in-addr.arpa

ipv4-mapped::ffff:a00:a600

/23 split into /30 · 128 subnets

close ×

#	network	host range	broadcast
1	10.0.166.0/30	10.0.166.1 – 10.0.166.2	10.0.166.3
2	10.0.166.4/30	10.0.166.5 – 10.0.166.6	10.0.166.7
3	10.0.166.8/30	10.0.166.9 – 10.0.166.10	10.0.166.11
4	10.0.166.12/30	10.0.166.13 – 10.0.166.14	10.0.166.15
5	10.0.166.16/30	10.0.166.17 – 10.0.166.18	10.0.166.19
6	10.0.166.20/30	10.0.166.21 – 10.0.166.22	10.0.166.23
7	10.0.166.24/30	10.0.166.25 – 10.0.166.26	10.0.166.27
8	10.0.166.28/30	10.0.166.29 – 10.0.166.30	10.0.166.31
9	10.0.166.32/30	10.0.166.33 – 10.0.166.34	10.0.166.35
10	10.0.166.36/30	10.0.166.37 – 10.0.166.38	10.0.166.39
11	10.0.166.40/30	10.0.166.41 – 10.0.166.42	10.0.166.43
12	10.0.166.44/30	10.0.166.45 – 10.0.166.46	10.0.166.47
13	10.0.166.48/30	10.0.166.49 – 10.0.166.50	10.0.166.51
14	10.0.166.52/30	10.0.166.53 – 10.0.166.54	10.0.166.55
15	10.0.166.56/30	10.0.166.57 – 10.0.166.58	10.0.166.59
16	10.0.166.60/30	10.0.166.61 – 10.0.166.62	10.0.166.63
17	10.0.166.64/30	10.0.166.65 – 10.0.166.66	10.0.166.67
18	10.0.166.68/30	10.0.166.69 – 10.0.166.70	10.0.166.71
19	10.0.166.72/30	10.0.166.73 – 10.0.166.74	10.0.166.75
20	10.0.166.76/30	10.0.166.77 – 10.0.166.78	10.0.166.79
21	10.0.166.80/30	10.0.166.81 – 10.0.166.82	10.0.166.83
22	10.0.166.84/30	10.0.166.85 – 10.0.166.86	10.0.166.87
23	10.0.166.88/30	10.0.166.89 – 10.0.166.90	10.0.166.91
24	10.0.166.92/30	10.0.166.93 – 10.0.166.94	10.0.166.95
25	10.0.166.96/30	10.0.166.97 – 10.0.166.98	10.0.166.99
26	10.0.166.100/30	10.0.166.101 – 10.0.166.102	10.0.166.103
27	10.0.166.104/30	10.0.166.105 – 10.0.166.106	10.0.166.107
28	10.0.166.108/30	10.0.166.109 – 10.0.166.110	10.0.166.111
29	10.0.166.112/30	10.0.166.113 – 10.0.166.114	10.0.166.115
30	10.0.166.116/30	10.0.166.117 – 10.0.166.118	10.0.166.119
31	10.0.166.120/30	10.0.166.121 – 10.0.166.122	10.0.166.123
32	10.0.166.124/30	10.0.166.125 – 10.0.166.126	10.0.166.127
33	10.0.166.128/30	10.0.166.129 – 10.0.166.130	10.0.166.131
34	10.0.166.132/30	10.0.166.133 – 10.0.166.134	10.0.166.135
35	10.0.166.136/30	10.0.166.137 – 10.0.166.138	10.0.166.139
36	10.0.166.140/30	10.0.166.141 – 10.0.166.142	10.0.166.143
37	10.0.166.144/30	10.0.166.145 – 10.0.166.146	10.0.166.147
38	10.0.166.148/30	10.0.166.149 – 10.0.166.150	10.0.166.151
39	10.0.166.152/30	10.0.166.153 – 10.0.166.154	10.0.166.155
40	10.0.166.156/30	10.0.166.157 – 10.0.166.158	10.0.166.159
41	10.0.166.160/30	10.0.166.161 – 10.0.166.162	10.0.166.163
42	10.0.166.164/30	10.0.166.165 – 10.0.166.166	10.0.166.167
43	10.0.166.168/30	10.0.166.169 – 10.0.166.170	10.0.166.171
44	10.0.166.172/30	10.0.166.173 – 10.0.166.174	10.0.166.175
45	10.0.166.176/30	10.0.166.177 – 10.0.166.178	10.0.166.179
46	10.0.166.180/30	10.0.166.181 – 10.0.166.182	10.0.166.183
47	10.0.166.184/30	10.0.166.185 – 10.0.166.186	10.0.166.187
48	10.0.166.188/30	10.0.166.189 – 10.0.166.190	10.0.166.191
49	10.0.166.192/30	10.0.166.193 – 10.0.166.194	10.0.166.195
50	10.0.166.196/30	10.0.166.197 – 10.0.166.198	10.0.166.199
51	10.0.166.200/30	10.0.166.201 – 10.0.166.202	10.0.166.203
52	10.0.166.204/30	10.0.166.205 – 10.0.166.206	10.0.166.207
53	10.0.166.208/30	10.0.166.209 – 10.0.166.210	10.0.166.211
54	10.0.166.212/30	10.0.166.213 – 10.0.166.214	10.0.166.215
55	10.0.166.216/30	10.0.166.217 – 10.0.166.218	10.0.166.219
56	10.0.166.220/30	10.0.166.221 – 10.0.166.222	10.0.166.223
57	10.0.166.224/30	10.0.166.225 – 10.0.166.226	10.0.166.227
58	10.0.166.228/30	10.0.166.229 – 10.0.166.230	10.0.166.231
59	10.0.166.232/30	10.0.166.233 – 10.0.166.234	10.0.166.235
60	10.0.166.236/30	10.0.166.237 – 10.0.166.238	10.0.166.239
61	10.0.166.240/30	10.0.166.241 – 10.0.166.242	10.0.166.243
62	10.0.166.244/30	10.0.166.245 – 10.0.166.246	10.0.166.247
63	10.0.166.248/30	10.0.166.249 – 10.0.166.250	10.0.166.251
64	10.0.166.252/30	10.0.166.253 – 10.0.166.254	10.0.166.255
65	10.0.167.0/30	10.0.167.1 – 10.0.167.2	10.0.167.3
66	10.0.167.4/30	10.0.167.5 – 10.0.167.6	10.0.167.7
67	10.0.167.8/30	10.0.167.9 – 10.0.167.10	10.0.167.11
68	10.0.167.12/30	10.0.167.13 – 10.0.167.14	10.0.167.15
69	10.0.167.16/30	10.0.167.17 – 10.0.167.18	10.0.167.19
70	10.0.167.20/30	10.0.167.21 – 10.0.167.22	10.0.167.23
71	10.0.167.24/30	10.0.167.25 – 10.0.167.26	10.0.167.27
72	10.0.167.28/30	10.0.167.29 – 10.0.167.30	10.0.167.31
73	10.0.167.32/30	10.0.167.33 – 10.0.167.34	10.0.167.35
74	10.0.167.36/30	10.0.167.37 – 10.0.167.38	10.0.167.39
75	10.0.167.40/30	10.0.167.41 – 10.0.167.42	10.0.167.43
76	10.0.167.44/30	10.0.167.45 – 10.0.167.46	10.0.167.47
77	10.0.167.48/30	10.0.167.49 – 10.0.167.50	10.0.167.51
78	10.0.167.52/30	10.0.167.53 – 10.0.167.54	10.0.167.55
79	10.0.167.56/30	10.0.167.57 – 10.0.167.58	10.0.167.59
80	10.0.167.60/30	10.0.167.61 – 10.0.167.62	10.0.167.63
81	10.0.167.64/30	10.0.167.65 – 10.0.167.66	10.0.167.67
82	10.0.167.68/30	10.0.167.69 – 10.0.167.70	10.0.167.71
83	10.0.167.72/30	10.0.167.73 – 10.0.167.74	10.0.167.75
84	10.0.167.76/30	10.0.167.77 – 10.0.167.78	10.0.167.79
85	10.0.167.80/30	10.0.167.81 – 10.0.167.82	10.0.167.83
86	10.0.167.84/30	10.0.167.85 – 10.0.167.86	10.0.167.87
87	10.0.167.88/30	10.0.167.89 – 10.0.167.90	10.0.167.91
88	10.0.167.92/30	10.0.167.93 – 10.0.167.94	10.0.167.95
89	10.0.167.96/30	10.0.167.97 – 10.0.167.98	10.0.167.99
90	10.0.167.100/30	10.0.167.101 – 10.0.167.102	10.0.167.103
91	10.0.167.104/30	10.0.167.105 – 10.0.167.106	10.0.167.107
92	10.0.167.108/30	10.0.167.109 – 10.0.167.110	10.0.167.111
93	10.0.167.112/30	10.0.167.113 – 10.0.167.114	10.0.167.115
94	10.0.167.116/30	10.0.167.117 – 10.0.167.118	10.0.167.119
95	10.0.167.120/30	10.0.167.121 – 10.0.167.122	10.0.167.123
96	10.0.167.124/30	10.0.167.125 – 10.0.167.126	10.0.167.127
97	10.0.167.128/30	10.0.167.129 – 10.0.167.130	10.0.167.131
98	10.0.167.132/30	10.0.167.133 – 10.0.167.134	10.0.167.135
99	10.0.167.136/30	10.0.167.137 – 10.0.167.138	10.0.167.139
100	10.0.167.140/30	10.0.167.141 – 10.0.167.142	10.0.167.143
101	10.0.167.144/30	10.0.167.145 – 10.0.167.146	10.0.167.147
102	10.0.167.148/30	10.0.167.149 – 10.0.167.150	10.0.167.151
103	10.0.167.152/30	10.0.167.153 – 10.0.167.154	10.0.167.155
104	10.0.167.156/30	10.0.167.157 – 10.0.167.158	10.0.167.159
105	10.0.167.160/30	10.0.167.161 – 10.0.167.162	10.0.167.163
106	10.0.167.164/30	10.0.167.165 – 10.0.167.166	10.0.167.167
107	10.0.167.168/30	10.0.167.169 – 10.0.167.170	10.0.167.171
108	10.0.167.172/30	10.0.167.173 – 10.0.167.174	10.0.167.175
109	10.0.167.176/30	10.0.167.177 – 10.0.167.178	10.0.167.179
110	10.0.167.180/30	10.0.167.181 – 10.0.167.182	10.0.167.183
111	10.0.167.184/30	10.0.167.185 – 10.0.167.186	10.0.167.187
112	10.0.167.188/30	10.0.167.189 – 10.0.167.190	10.0.167.191
113	10.0.167.192/30	10.0.167.193 – 10.0.167.194	10.0.167.195
114	10.0.167.196/30	10.0.167.197 – 10.0.167.198	10.0.167.199
115	10.0.167.200/30	10.0.167.201 – 10.0.167.202	10.0.167.203
116	10.0.167.204/30	10.0.167.205 – 10.0.167.206	10.0.167.207
117	10.0.167.208/30	10.0.167.209 – 10.0.167.210	10.0.167.211
118	10.0.167.212/30	10.0.167.213 – 10.0.167.214	10.0.167.215
119	10.0.167.216/30	10.0.167.217 – 10.0.167.218	10.0.167.219
120	10.0.167.220/30	10.0.167.221 – 10.0.167.222	10.0.167.223
121	10.0.167.224/30	10.0.167.225 – 10.0.167.226	10.0.167.227
122	10.0.167.228/30	10.0.167.229 – 10.0.167.230	10.0.167.231
123	10.0.167.232/30	10.0.167.233 – 10.0.167.234	10.0.167.235
124	10.0.167.236/30	10.0.167.237 – 10.0.167.238	10.0.167.239
125	10.0.167.240/30	10.0.167.241 – 10.0.167.242	10.0.167.243
126	10.0.167.244/30	10.0.167.245 – 10.0.167.246	10.0.167.247
127	10.0.167.248/30	10.0.167.249 – 10.0.167.250	10.0.167.251
128	10.0.167.252/30	10.0.167.253 – 10.0.167.254	10.0.167.255

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 →