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)10.166.45.0/24

network10.166.45.0/24

broadcast10.166.45.255

first host10.166.45.1

last host10.166.45.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.166.45.0/24

address00001010.10100110.00101101.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.10100110.00101101.00000000

broadcast00001010.10100110.00101101.11111111

green = network part, grey = host part

hex0x0aa62d00

decimal178662656

reverse dns0.45.166.10.in-addr.arpa

ipv4-mapped::ffff:aa6:2d00

/24 split into /31 · 128 subnets

close ×

#	network	host range	broadcast
1	10.166.45.0/31	10.166.45.0 – 10.166.45.1	10.166.45.1
2	10.166.45.2/31	10.166.45.2 – 10.166.45.3	10.166.45.3
3	10.166.45.4/31	10.166.45.4 – 10.166.45.5	10.166.45.5
4	10.166.45.6/31	10.166.45.6 – 10.166.45.7	10.166.45.7
5	10.166.45.8/31	10.166.45.8 – 10.166.45.9	10.166.45.9
6	10.166.45.10/31	10.166.45.10 – 10.166.45.11	10.166.45.11
7	10.166.45.12/31	10.166.45.12 – 10.166.45.13	10.166.45.13
8	10.166.45.14/31	10.166.45.14 – 10.166.45.15	10.166.45.15
9	10.166.45.16/31	10.166.45.16 – 10.166.45.17	10.166.45.17
10	10.166.45.18/31	10.166.45.18 – 10.166.45.19	10.166.45.19
11	10.166.45.20/31	10.166.45.20 – 10.166.45.21	10.166.45.21
12	10.166.45.22/31	10.166.45.22 – 10.166.45.23	10.166.45.23
13	10.166.45.24/31	10.166.45.24 – 10.166.45.25	10.166.45.25
14	10.166.45.26/31	10.166.45.26 – 10.166.45.27	10.166.45.27
15	10.166.45.28/31	10.166.45.28 – 10.166.45.29	10.166.45.29
16	10.166.45.30/31	10.166.45.30 – 10.166.45.31	10.166.45.31
17	10.166.45.32/31	10.166.45.32 – 10.166.45.33	10.166.45.33
18	10.166.45.34/31	10.166.45.34 – 10.166.45.35	10.166.45.35
19	10.166.45.36/31	10.166.45.36 – 10.166.45.37	10.166.45.37
20	10.166.45.38/31	10.166.45.38 – 10.166.45.39	10.166.45.39
21	10.166.45.40/31	10.166.45.40 – 10.166.45.41	10.166.45.41
22	10.166.45.42/31	10.166.45.42 – 10.166.45.43	10.166.45.43
23	10.166.45.44/31	10.166.45.44 – 10.166.45.45	10.166.45.45
24	10.166.45.46/31	10.166.45.46 – 10.166.45.47	10.166.45.47
25	10.166.45.48/31	10.166.45.48 – 10.166.45.49	10.166.45.49
26	10.166.45.50/31	10.166.45.50 – 10.166.45.51	10.166.45.51
27	10.166.45.52/31	10.166.45.52 – 10.166.45.53	10.166.45.53
28	10.166.45.54/31	10.166.45.54 – 10.166.45.55	10.166.45.55
29	10.166.45.56/31	10.166.45.56 – 10.166.45.57	10.166.45.57
30	10.166.45.58/31	10.166.45.58 – 10.166.45.59	10.166.45.59
31	10.166.45.60/31	10.166.45.60 – 10.166.45.61	10.166.45.61
32	10.166.45.62/31	10.166.45.62 – 10.166.45.63	10.166.45.63
33	10.166.45.64/31	10.166.45.64 – 10.166.45.65	10.166.45.65
34	10.166.45.66/31	10.166.45.66 – 10.166.45.67	10.166.45.67
35	10.166.45.68/31	10.166.45.68 – 10.166.45.69	10.166.45.69
36	10.166.45.70/31	10.166.45.70 – 10.166.45.71	10.166.45.71
37	10.166.45.72/31	10.166.45.72 – 10.166.45.73	10.166.45.73
38	10.166.45.74/31	10.166.45.74 – 10.166.45.75	10.166.45.75
39	10.166.45.76/31	10.166.45.76 – 10.166.45.77	10.166.45.77
40	10.166.45.78/31	10.166.45.78 – 10.166.45.79	10.166.45.79
41	10.166.45.80/31	10.166.45.80 – 10.166.45.81	10.166.45.81
42	10.166.45.82/31	10.166.45.82 – 10.166.45.83	10.166.45.83
43	10.166.45.84/31	10.166.45.84 – 10.166.45.85	10.166.45.85
44	10.166.45.86/31	10.166.45.86 – 10.166.45.87	10.166.45.87
45	10.166.45.88/31	10.166.45.88 – 10.166.45.89	10.166.45.89
46	10.166.45.90/31	10.166.45.90 – 10.166.45.91	10.166.45.91
47	10.166.45.92/31	10.166.45.92 – 10.166.45.93	10.166.45.93
48	10.166.45.94/31	10.166.45.94 – 10.166.45.95	10.166.45.95
49	10.166.45.96/31	10.166.45.96 – 10.166.45.97	10.166.45.97
50	10.166.45.98/31	10.166.45.98 – 10.166.45.99	10.166.45.99
51	10.166.45.100/31	10.166.45.100 – 10.166.45.101	10.166.45.101
52	10.166.45.102/31	10.166.45.102 – 10.166.45.103	10.166.45.103
53	10.166.45.104/31	10.166.45.104 – 10.166.45.105	10.166.45.105
54	10.166.45.106/31	10.166.45.106 – 10.166.45.107	10.166.45.107
55	10.166.45.108/31	10.166.45.108 – 10.166.45.109	10.166.45.109
56	10.166.45.110/31	10.166.45.110 – 10.166.45.111	10.166.45.111
57	10.166.45.112/31	10.166.45.112 – 10.166.45.113	10.166.45.113
58	10.166.45.114/31	10.166.45.114 – 10.166.45.115	10.166.45.115
59	10.166.45.116/31	10.166.45.116 – 10.166.45.117	10.166.45.117
60	10.166.45.118/31	10.166.45.118 – 10.166.45.119	10.166.45.119
61	10.166.45.120/31	10.166.45.120 – 10.166.45.121	10.166.45.121
62	10.166.45.122/31	10.166.45.122 – 10.166.45.123	10.166.45.123
63	10.166.45.124/31	10.166.45.124 – 10.166.45.125	10.166.45.125
64	10.166.45.126/31	10.166.45.126 – 10.166.45.127	10.166.45.127
65	10.166.45.128/31	10.166.45.128 – 10.166.45.129	10.166.45.129
66	10.166.45.130/31	10.166.45.130 – 10.166.45.131	10.166.45.131
67	10.166.45.132/31	10.166.45.132 – 10.166.45.133	10.166.45.133
68	10.166.45.134/31	10.166.45.134 – 10.166.45.135	10.166.45.135
69	10.166.45.136/31	10.166.45.136 – 10.166.45.137	10.166.45.137
70	10.166.45.138/31	10.166.45.138 – 10.166.45.139	10.166.45.139
71	10.166.45.140/31	10.166.45.140 – 10.166.45.141	10.166.45.141
72	10.166.45.142/31	10.166.45.142 – 10.166.45.143	10.166.45.143
73	10.166.45.144/31	10.166.45.144 – 10.166.45.145	10.166.45.145
74	10.166.45.146/31	10.166.45.146 – 10.166.45.147	10.166.45.147
75	10.166.45.148/31	10.166.45.148 – 10.166.45.149	10.166.45.149
76	10.166.45.150/31	10.166.45.150 – 10.166.45.151	10.166.45.151
77	10.166.45.152/31	10.166.45.152 – 10.166.45.153	10.166.45.153
78	10.166.45.154/31	10.166.45.154 – 10.166.45.155	10.166.45.155
79	10.166.45.156/31	10.166.45.156 – 10.166.45.157	10.166.45.157
80	10.166.45.158/31	10.166.45.158 – 10.166.45.159	10.166.45.159
81	10.166.45.160/31	10.166.45.160 – 10.166.45.161	10.166.45.161
82	10.166.45.162/31	10.166.45.162 – 10.166.45.163	10.166.45.163
83	10.166.45.164/31	10.166.45.164 – 10.166.45.165	10.166.45.165
84	10.166.45.166/31	10.166.45.166 – 10.166.45.167	10.166.45.167
85	10.166.45.168/31	10.166.45.168 – 10.166.45.169	10.166.45.169
86	10.166.45.170/31	10.166.45.170 – 10.166.45.171	10.166.45.171
87	10.166.45.172/31	10.166.45.172 – 10.166.45.173	10.166.45.173
88	10.166.45.174/31	10.166.45.174 – 10.166.45.175	10.166.45.175
89	10.166.45.176/31	10.166.45.176 – 10.166.45.177	10.166.45.177
90	10.166.45.178/31	10.166.45.178 – 10.166.45.179	10.166.45.179
91	10.166.45.180/31	10.166.45.180 – 10.166.45.181	10.166.45.181
92	10.166.45.182/31	10.166.45.182 – 10.166.45.183	10.166.45.183
93	10.166.45.184/31	10.166.45.184 – 10.166.45.185	10.166.45.185
94	10.166.45.186/31	10.166.45.186 – 10.166.45.187	10.166.45.187
95	10.166.45.188/31	10.166.45.188 – 10.166.45.189	10.166.45.189
96	10.166.45.190/31	10.166.45.190 – 10.166.45.191	10.166.45.191
97	10.166.45.192/31	10.166.45.192 – 10.166.45.193	10.166.45.193
98	10.166.45.194/31	10.166.45.194 – 10.166.45.195	10.166.45.195
99	10.166.45.196/31	10.166.45.196 – 10.166.45.197	10.166.45.197
100	10.166.45.198/31	10.166.45.198 – 10.166.45.199	10.166.45.199
101	10.166.45.200/31	10.166.45.200 – 10.166.45.201	10.166.45.201
102	10.166.45.202/31	10.166.45.202 – 10.166.45.203	10.166.45.203
103	10.166.45.204/31	10.166.45.204 – 10.166.45.205	10.166.45.205
104	10.166.45.206/31	10.166.45.206 – 10.166.45.207	10.166.45.207
105	10.166.45.208/31	10.166.45.208 – 10.166.45.209	10.166.45.209
106	10.166.45.210/31	10.166.45.210 – 10.166.45.211	10.166.45.211
107	10.166.45.212/31	10.166.45.212 – 10.166.45.213	10.166.45.213
108	10.166.45.214/31	10.166.45.214 – 10.166.45.215	10.166.45.215
109	10.166.45.216/31	10.166.45.216 – 10.166.45.217	10.166.45.217
110	10.166.45.218/31	10.166.45.218 – 10.166.45.219	10.166.45.219
111	10.166.45.220/31	10.166.45.220 – 10.166.45.221	10.166.45.221
112	10.166.45.222/31	10.166.45.222 – 10.166.45.223	10.166.45.223
113	10.166.45.224/31	10.166.45.224 – 10.166.45.225	10.166.45.225
114	10.166.45.226/31	10.166.45.226 – 10.166.45.227	10.166.45.227
115	10.166.45.228/31	10.166.45.228 – 10.166.45.229	10.166.45.229
116	10.166.45.230/31	10.166.45.230 – 10.166.45.231	10.166.45.231
117	10.166.45.232/31	10.166.45.232 – 10.166.45.233	10.166.45.233
118	10.166.45.234/31	10.166.45.234 – 10.166.45.235	10.166.45.235
119	10.166.45.236/31	10.166.45.236 – 10.166.45.237	10.166.45.237
120	10.166.45.238/31	10.166.45.238 – 10.166.45.239	10.166.45.239
121	10.166.45.240/31	10.166.45.240 – 10.166.45.241	10.166.45.241
122	10.166.45.242/31	10.166.45.242 – 10.166.45.243	10.166.45.243
123	10.166.45.244/31	10.166.45.244 – 10.166.45.245	10.166.45.245
124	10.166.45.246/31	10.166.45.246 – 10.166.45.247	10.166.45.247
125	10.166.45.248/31	10.166.45.248 – 10.166.45.249	10.166.45.249
126	10.166.45.250/31	10.166.45.250 – 10.166.45.251	10.166.45.251
127	10.166.45.252/31	10.166.45.252 – 10.166.45.253	10.166.45.253
128	10.166.45.254/31	10.166.45.254 – 10.166.45.255	10.166.45.255

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 →