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)10.166.91.0/24

network10.166.91.0/24

broadcast10.166.91.255

first host10.166.91.1

last host10.166.91.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.166.91.0/24

address00001010.10100110.01011011.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.10100110.01011011.00000000

broadcast00001010.10100110.01011011.11111111

green = network part, grey = host part

hex0x0aa65b00

decimal178674432

reverse dns0.91.166.10.in-addr.arpa

ipv4-mapped::ffff:aa6:5b00

/24 split into /31 · 128 subnets

close ×

#	network	host range	broadcast
1	10.166.91.0/31	10.166.91.0 – 10.166.91.1	10.166.91.1
2	10.166.91.2/31	10.166.91.2 – 10.166.91.3	10.166.91.3
3	10.166.91.4/31	10.166.91.4 – 10.166.91.5	10.166.91.5
4	10.166.91.6/31	10.166.91.6 – 10.166.91.7	10.166.91.7
5	10.166.91.8/31	10.166.91.8 – 10.166.91.9	10.166.91.9
6	10.166.91.10/31	10.166.91.10 – 10.166.91.11	10.166.91.11
7	10.166.91.12/31	10.166.91.12 – 10.166.91.13	10.166.91.13
8	10.166.91.14/31	10.166.91.14 – 10.166.91.15	10.166.91.15
9	10.166.91.16/31	10.166.91.16 – 10.166.91.17	10.166.91.17
10	10.166.91.18/31	10.166.91.18 – 10.166.91.19	10.166.91.19
11	10.166.91.20/31	10.166.91.20 – 10.166.91.21	10.166.91.21
12	10.166.91.22/31	10.166.91.22 – 10.166.91.23	10.166.91.23
13	10.166.91.24/31	10.166.91.24 – 10.166.91.25	10.166.91.25
14	10.166.91.26/31	10.166.91.26 – 10.166.91.27	10.166.91.27
15	10.166.91.28/31	10.166.91.28 – 10.166.91.29	10.166.91.29
16	10.166.91.30/31	10.166.91.30 – 10.166.91.31	10.166.91.31
17	10.166.91.32/31	10.166.91.32 – 10.166.91.33	10.166.91.33
18	10.166.91.34/31	10.166.91.34 – 10.166.91.35	10.166.91.35
19	10.166.91.36/31	10.166.91.36 – 10.166.91.37	10.166.91.37
20	10.166.91.38/31	10.166.91.38 – 10.166.91.39	10.166.91.39
21	10.166.91.40/31	10.166.91.40 – 10.166.91.41	10.166.91.41
22	10.166.91.42/31	10.166.91.42 – 10.166.91.43	10.166.91.43
23	10.166.91.44/31	10.166.91.44 – 10.166.91.45	10.166.91.45
24	10.166.91.46/31	10.166.91.46 – 10.166.91.47	10.166.91.47
25	10.166.91.48/31	10.166.91.48 – 10.166.91.49	10.166.91.49
26	10.166.91.50/31	10.166.91.50 – 10.166.91.51	10.166.91.51
27	10.166.91.52/31	10.166.91.52 – 10.166.91.53	10.166.91.53
28	10.166.91.54/31	10.166.91.54 – 10.166.91.55	10.166.91.55
29	10.166.91.56/31	10.166.91.56 – 10.166.91.57	10.166.91.57
30	10.166.91.58/31	10.166.91.58 – 10.166.91.59	10.166.91.59
31	10.166.91.60/31	10.166.91.60 – 10.166.91.61	10.166.91.61
32	10.166.91.62/31	10.166.91.62 – 10.166.91.63	10.166.91.63
33	10.166.91.64/31	10.166.91.64 – 10.166.91.65	10.166.91.65
34	10.166.91.66/31	10.166.91.66 – 10.166.91.67	10.166.91.67
35	10.166.91.68/31	10.166.91.68 – 10.166.91.69	10.166.91.69
36	10.166.91.70/31	10.166.91.70 – 10.166.91.71	10.166.91.71
37	10.166.91.72/31	10.166.91.72 – 10.166.91.73	10.166.91.73
38	10.166.91.74/31	10.166.91.74 – 10.166.91.75	10.166.91.75
39	10.166.91.76/31	10.166.91.76 – 10.166.91.77	10.166.91.77
40	10.166.91.78/31	10.166.91.78 – 10.166.91.79	10.166.91.79
41	10.166.91.80/31	10.166.91.80 – 10.166.91.81	10.166.91.81
42	10.166.91.82/31	10.166.91.82 – 10.166.91.83	10.166.91.83
43	10.166.91.84/31	10.166.91.84 – 10.166.91.85	10.166.91.85
44	10.166.91.86/31	10.166.91.86 – 10.166.91.87	10.166.91.87
45	10.166.91.88/31	10.166.91.88 – 10.166.91.89	10.166.91.89
46	10.166.91.90/31	10.166.91.90 – 10.166.91.91	10.166.91.91
47	10.166.91.92/31	10.166.91.92 – 10.166.91.93	10.166.91.93
48	10.166.91.94/31	10.166.91.94 – 10.166.91.95	10.166.91.95
49	10.166.91.96/31	10.166.91.96 – 10.166.91.97	10.166.91.97
50	10.166.91.98/31	10.166.91.98 – 10.166.91.99	10.166.91.99
51	10.166.91.100/31	10.166.91.100 – 10.166.91.101	10.166.91.101
52	10.166.91.102/31	10.166.91.102 – 10.166.91.103	10.166.91.103
53	10.166.91.104/31	10.166.91.104 – 10.166.91.105	10.166.91.105
54	10.166.91.106/31	10.166.91.106 – 10.166.91.107	10.166.91.107
55	10.166.91.108/31	10.166.91.108 – 10.166.91.109	10.166.91.109
56	10.166.91.110/31	10.166.91.110 – 10.166.91.111	10.166.91.111
57	10.166.91.112/31	10.166.91.112 – 10.166.91.113	10.166.91.113
58	10.166.91.114/31	10.166.91.114 – 10.166.91.115	10.166.91.115
59	10.166.91.116/31	10.166.91.116 – 10.166.91.117	10.166.91.117
60	10.166.91.118/31	10.166.91.118 – 10.166.91.119	10.166.91.119
61	10.166.91.120/31	10.166.91.120 – 10.166.91.121	10.166.91.121
62	10.166.91.122/31	10.166.91.122 – 10.166.91.123	10.166.91.123
63	10.166.91.124/31	10.166.91.124 – 10.166.91.125	10.166.91.125
64	10.166.91.126/31	10.166.91.126 – 10.166.91.127	10.166.91.127
65	10.166.91.128/31	10.166.91.128 – 10.166.91.129	10.166.91.129
66	10.166.91.130/31	10.166.91.130 – 10.166.91.131	10.166.91.131
67	10.166.91.132/31	10.166.91.132 – 10.166.91.133	10.166.91.133
68	10.166.91.134/31	10.166.91.134 – 10.166.91.135	10.166.91.135
69	10.166.91.136/31	10.166.91.136 – 10.166.91.137	10.166.91.137
70	10.166.91.138/31	10.166.91.138 – 10.166.91.139	10.166.91.139
71	10.166.91.140/31	10.166.91.140 – 10.166.91.141	10.166.91.141
72	10.166.91.142/31	10.166.91.142 – 10.166.91.143	10.166.91.143
73	10.166.91.144/31	10.166.91.144 – 10.166.91.145	10.166.91.145
74	10.166.91.146/31	10.166.91.146 – 10.166.91.147	10.166.91.147
75	10.166.91.148/31	10.166.91.148 – 10.166.91.149	10.166.91.149
76	10.166.91.150/31	10.166.91.150 – 10.166.91.151	10.166.91.151
77	10.166.91.152/31	10.166.91.152 – 10.166.91.153	10.166.91.153
78	10.166.91.154/31	10.166.91.154 – 10.166.91.155	10.166.91.155
79	10.166.91.156/31	10.166.91.156 – 10.166.91.157	10.166.91.157
80	10.166.91.158/31	10.166.91.158 – 10.166.91.159	10.166.91.159
81	10.166.91.160/31	10.166.91.160 – 10.166.91.161	10.166.91.161
82	10.166.91.162/31	10.166.91.162 – 10.166.91.163	10.166.91.163
83	10.166.91.164/31	10.166.91.164 – 10.166.91.165	10.166.91.165
84	10.166.91.166/31	10.166.91.166 – 10.166.91.167	10.166.91.167
85	10.166.91.168/31	10.166.91.168 – 10.166.91.169	10.166.91.169
86	10.166.91.170/31	10.166.91.170 – 10.166.91.171	10.166.91.171
87	10.166.91.172/31	10.166.91.172 – 10.166.91.173	10.166.91.173
88	10.166.91.174/31	10.166.91.174 – 10.166.91.175	10.166.91.175
89	10.166.91.176/31	10.166.91.176 – 10.166.91.177	10.166.91.177
90	10.166.91.178/31	10.166.91.178 – 10.166.91.179	10.166.91.179
91	10.166.91.180/31	10.166.91.180 – 10.166.91.181	10.166.91.181
92	10.166.91.182/31	10.166.91.182 – 10.166.91.183	10.166.91.183
93	10.166.91.184/31	10.166.91.184 – 10.166.91.185	10.166.91.185
94	10.166.91.186/31	10.166.91.186 – 10.166.91.187	10.166.91.187
95	10.166.91.188/31	10.166.91.188 – 10.166.91.189	10.166.91.189
96	10.166.91.190/31	10.166.91.190 – 10.166.91.191	10.166.91.191
97	10.166.91.192/31	10.166.91.192 – 10.166.91.193	10.166.91.193
98	10.166.91.194/31	10.166.91.194 – 10.166.91.195	10.166.91.195
99	10.166.91.196/31	10.166.91.196 – 10.166.91.197	10.166.91.197
100	10.166.91.198/31	10.166.91.198 – 10.166.91.199	10.166.91.199
101	10.166.91.200/31	10.166.91.200 – 10.166.91.201	10.166.91.201
102	10.166.91.202/31	10.166.91.202 – 10.166.91.203	10.166.91.203
103	10.166.91.204/31	10.166.91.204 – 10.166.91.205	10.166.91.205
104	10.166.91.206/31	10.166.91.206 – 10.166.91.207	10.166.91.207
105	10.166.91.208/31	10.166.91.208 – 10.166.91.209	10.166.91.209
106	10.166.91.210/31	10.166.91.210 – 10.166.91.211	10.166.91.211
107	10.166.91.212/31	10.166.91.212 – 10.166.91.213	10.166.91.213
108	10.166.91.214/31	10.166.91.214 – 10.166.91.215	10.166.91.215
109	10.166.91.216/31	10.166.91.216 – 10.166.91.217	10.166.91.217
110	10.166.91.218/31	10.166.91.218 – 10.166.91.219	10.166.91.219
111	10.166.91.220/31	10.166.91.220 – 10.166.91.221	10.166.91.221
112	10.166.91.222/31	10.166.91.222 – 10.166.91.223	10.166.91.223
113	10.166.91.224/31	10.166.91.224 – 10.166.91.225	10.166.91.225
114	10.166.91.226/31	10.166.91.226 – 10.166.91.227	10.166.91.227
115	10.166.91.228/31	10.166.91.228 – 10.166.91.229	10.166.91.229
116	10.166.91.230/31	10.166.91.230 – 10.166.91.231	10.166.91.231
117	10.166.91.232/31	10.166.91.232 – 10.166.91.233	10.166.91.233
118	10.166.91.234/31	10.166.91.234 – 10.166.91.235	10.166.91.235
119	10.166.91.236/31	10.166.91.236 – 10.166.91.237	10.166.91.237
120	10.166.91.238/31	10.166.91.238 – 10.166.91.239	10.166.91.239
121	10.166.91.240/31	10.166.91.240 – 10.166.91.241	10.166.91.241
122	10.166.91.242/31	10.166.91.242 – 10.166.91.243	10.166.91.243
123	10.166.91.244/31	10.166.91.244 – 10.166.91.245	10.166.91.245
124	10.166.91.246/31	10.166.91.246 – 10.166.91.247	10.166.91.247
125	10.166.91.248/31	10.166.91.248 – 10.166.91.249	10.166.91.249
126	10.166.91.250/31	10.166.91.250 – 10.166.91.251	10.166.91.251
127	10.166.91.252/31	10.166.91.252 – 10.166.91.253	10.166.91.253
128	10.166.91.254/31	10.166.91.254 – 10.166.91.255	10.166.91.255

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 →