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)10.2.87.0/24

network10.2.87.0/24

broadcast10.2.87.255

first host10.2.87.1

last host10.2.87.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.2.87.0/24

address00001010.00000010.01010111.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.00000010.01010111.00000000

broadcast00001010.00000010.01010111.11111111

green = network part, grey = host part

hex0x0a025700

decimal167925504

reverse dns0.87.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:5700

/24 split into /31 · 128 subnets

close ×

#	network	host range	broadcast
1	10.2.87.0/31	10.2.87.0 – 10.2.87.1	10.2.87.1
2	10.2.87.2/31	10.2.87.2 – 10.2.87.3	10.2.87.3
3	10.2.87.4/31	10.2.87.4 – 10.2.87.5	10.2.87.5
4	10.2.87.6/31	10.2.87.6 – 10.2.87.7	10.2.87.7
5	10.2.87.8/31	10.2.87.8 – 10.2.87.9	10.2.87.9
6	10.2.87.10/31	10.2.87.10 – 10.2.87.11	10.2.87.11
7	10.2.87.12/31	10.2.87.12 – 10.2.87.13	10.2.87.13
8	10.2.87.14/31	10.2.87.14 – 10.2.87.15	10.2.87.15
9	10.2.87.16/31	10.2.87.16 – 10.2.87.17	10.2.87.17
10	10.2.87.18/31	10.2.87.18 – 10.2.87.19	10.2.87.19
11	10.2.87.20/31	10.2.87.20 – 10.2.87.21	10.2.87.21
12	10.2.87.22/31	10.2.87.22 – 10.2.87.23	10.2.87.23
13	10.2.87.24/31	10.2.87.24 – 10.2.87.25	10.2.87.25
14	10.2.87.26/31	10.2.87.26 – 10.2.87.27	10.2.87.27
15	10.2.87.28/31	10.2.87.28 – 10.2.87.29	10.2.87.29
16	10.2.87.30/31	10.2.87.30 – 10.2.87.31	10.2.87.31
17	10.2.87.32/31	10.2.87.32 – 10.2.87.33	10.2.87.33
18	10.2.87.34/31	10.2.87.34 – 10.2.87.35	10.2.87.35
19	10.2.87.36/31	10.2.87.36 – 10.2.87.37	10.2.87.37
20	10.2.87.38/31	10.2.87.38 – 10.2.87.39	10.2.87.39
21	10.2.87.40/31	10.2.87.40 – 10.2.87.41	10.2.87.41
22	10.2.87.42/31	10.2.87.42 – 10.2.87.43	10.2.87.43
23	10.2.87.44/31	10.2.87.44 – 10.2.87.45	10.2.87.45
24	10.2.87.46/31	10.2.87.46 – 10.2.87.47	10.2.87.47
25	10.2.87.48/31	10.2.87.48 – 10.2.87.49	10.2.87.49
26	10.2.87.50/31	10.2.87.50 – 10.2.87.51	10.2.87.51
27	10.2.87.52/31	10.2.87.52 – 10.2.87.53	10.2.87.53
28	10.2.87.54/31	10.2.87.54 – 10.2.87.55	10.2.87.55
29	10.2.87.56/31	10.2.87.56 – 10.2.87.57	10.2.87.57
30	10.2.87.58/31	10.2.87.58 – 10.2.87.59	10.2.87.59
31	10.2.87.60/31	10.2.87.60 – 10.2.87.61	10.2.87.61
32	10.2.87.62/31	10.2.87.62 – 10.2.87.63	10.2.87.63
33	10.2.87.64/31	10.2.87.64 – 10.2.87.65	10.2.87.65
34	10.2.87.66/31	10.2.87.66 – 10.2.87.67	10.2.87.67
35	10.2.87.68/31	10.2.87.68 – 10.2.87.69	10.2.87.69
36	10.2.87.70/31	10.2.87.70 – 10.2.87.71	10.2.87.71
37	10.2.87.72/31	10.2.87.72 – 10.2.87.73	10.2.87.73
38	10.2.87.74/31	10.2.87.74 – 10.2.87.75	10.2.87.75
39	10.2.87.76/31	10.2.87.76 – 10.2.87.77	10.2.87.77
40	10.2.87.78/31	10.2.87.78 – 10.2.87.79	10.2.87.79
41	10.2.87.80/31	10.2.87.80 – 10.2.87.81	10.2.87.81
42	10.2.87.82/31	10.2.87.82 – 10.2.87.83	10.2.87.83
43	10.2.87.84/31	10.2.87.84 – 10.2.87.85	10.2.87.85
44	10.2.87.86/31	10.2.87.86 – 10.2.87.87	10.2.87.87
45	10.2.87.88/31	10.2.87.88 – 10.2.87.89	10.2.87.89
46	10.2.87.90/31	10.2.87.90 – 10.2.87.91	10.2.87.91
47	10.2.87.92/31	10.2.87.92 – 10.2.87.93	10.2.87.93
48	10.2.87.94/31	10.2.87.94 – 10.2.87.95	10.2.87.95
49	10.2.87.96/31	10.2.87.96 – 10.2.87.97	10.2.87.97
50	10.2.87.98/31	10.2.87.98 – 10.2.87.99	10.2.87.99
51	10.2.87.100/31	10.2.87.100 – 10.2.87.101	10.2.87.101
52	10.2.87.102/31	10.2.87.102 – 10.2.87.103	10.2.87.103
53	10.2.87.104/31	10.2.87.104 – 10.2.87.105	10.2.87.105
54	10.2.87.106/31	10.2.87.106 – 10.2.87.107	10.2.87.107
55	10.2.87.108/31	10.2.87.108 – 10.2.87.109	10.2.87.109
56	10.2.87.110/31	10.2.87.110 – 10.2.87.111	10.2.87.111
57	10.2.87.112/31	10.2.87.112 – 10.2.87.113	10.2.87.113
58	10.2.87.114/31	10.2.87.114 – 10.2.87.115	10.2.87.115
59	10.2.87.116/31	10.2.87.116 – 10.2.87.117	10.2.87.117
60	10.2.87.118/31	10.2.87.118 – 10.2.87.119	10.2.87.119
61	10.2.87.120/31	10.2.87.120 – 10.2.87.121	10.2.87.121
62	10.2.87.122/31	10.2.87.122 – 10.2.87.123	10.2.87.123
63	10.2.87.124/31	10.2.87.124 – 10.2.87.125	10.2.87.125
64	10.2.87.126/31	10.2.87.126 – 10.2.87.127	10.2.87.127
65	10.2.87.128/31	10.2.87.128 – 10.2.87.129	10.2.87.129
66	10.2.87.130/31	10.2.87.130 – 10.2.87.131	10.2.87.131
67	10.2.87.132/31	10.2.87.132 – 10.2.87.133	10.2.87.133
68	10.2.87.134/31	10.2.87.134 – 10.2.87.135	10.2.87.135
69	10.2.87.136/31	10.2.87.136 – 10.2.87.137	10.2.87.137
70	10.2.87.138/31	10.2.87.138 – 10.2.87.139	10.2.87.139
71	10.2.87.140/31	10.2.87.140 – 10.2.87.141	10.2.87.141
72	10.2.87.142/31	10.2.87.142 – 10.2.87.143	10.2.87.143
73	10.2.87.144/31	10.2.87.144 – 10.2.87.145	10.2.87.145
74	10.2.87.146/31	10.2.87.146 – 10.2.87.147	10.2.87.147
75	10.2.87.148/31	10.2.87.148 – 10.2.87.149	10.2.87.149
76	10.2.87.150/31	10.2.87.150 – 10.2.87.151	10.2.87.151
77	10.2.87.152/31	10.2.87.152 – 10.2.87.153	10.2.87.153
78	10.2.87.154/31	10.2.87.154 – 10.2.87.155	10.2.87.155
79	10.2.87.156/31	10.2.87.156 – 10.2.87.157	10.2.87.157
80	10.2.87.158/31	10.2.87.158 – 10.2.87.159	10.2.87.159
81	10.2.87.160/31	10.2.87.160 – 10.2.87.161	10.2.87.161
82	10.2.87.162/31	10.2.87.162 – 10.2.87.163	10.2.87.163
83	10.2.87.164/31	10.2.87.164 – 10.2.87.165	10.2.87.165
84	10.2.87.166/31	10.2.87.166 – 10.2.87.167	10.2.87.167
85	10.2.87.168/31	10.2.87.168 – 10.2.87.169	10.2.87.169
86	10.2.87.170/31	10.2.87.170 – 10.2.87.171	10.2.87.171
87	10.2.87.172/31	10.2.87.172 – 10.2.87.173	10.2.87.173
88	10.2.87.174/31	10.2.87.174 – 10.2.87.175	10.2.87.175
89	10.2.87.176/31	10.2.87.176 – 10.2.87.177	10.2.87.177
90	10.2.87.178/31	10.2.87.178 – 10.2.87.179	10.2.87.179
91	10.2.87.180/31	10.2.87.180 – 10.2.87.181	10.2.87.181
92	10.2.87.182/31	10.2.87.182 – 10.2.87.183	10.2.87.183
93	10.2.87.184/31	10.2.87.184 – 10.2.87.185	10.2.87.185
94	10.2.87.186/31	10.2.87.186 – 10.2.87.187	10.2.87.187
95	10.2.87.188/31	10.2.87.188 – 10.2.87.189	10.2.87.189
96	10.2.87.190/31	10.2.87.190 – 10.2.87.191	10.2.87.191
97	10.2.87.192/31	10.2.87.192 – 10.2.87.193	10.2.87.193
98	10.2.87.194/31	10.2.87.194 – 10.2.87.195	10.2.87.195
99	10.2.87.196/31	10.2.87.196 – 10.2.87.197	10.2.87.197
100	10.2.87.198/31	10.2.87.198 – 10.2.87.199	10.2.87.199
101	10.2.87.200/31	10.2.87.200 – 10.2.87.201	10.2.87.201
102	10.2.87.202/31	10.2.87.202 – 10.2.87.203	10.2.87.203
103	10.2.87.204/31	10.2.87.204 – 10.2.87.205	10.2.87.205
104	10.2.87.206/31	10.2.87.206 – 10.2.87.207	10.2.87.207
105	10.2.87.208/31	10.2.87.208 – 10.2.87.209	10.2.87.209
106	10.2.87.210/31	10.2.87.210 – 10.2.87.211	10.2.87.211
107	10.2.87.212/31	10.2.87.212 – 10.2.87.213	10.2.87.213
108	10.2.87.214/31	10.2.87.214 – 10.2.87.215	10.2.87.215
109	10.2.87.216/31	10.2.87.216 – 10.2.87.217	10.2.87.217
110	10.2.87.218/31	10.2.87.218 – 10.2.87.219	10.2.87.219
111	10.2.87.220/31	10.2.87.220 – 10.2.87.221	10.2.87.221
112	10.2.87.222/31	10.2.87.222 – 10.2.87.223	10.2.87.223
113	10.2.87.224/31	10.2.87.224 – 10.2.87.225	10.2.87.225
114	10.2.87.226/31	10.2.87.226 – 10.2.87.227	10.2.87.227
115	10.2.87.228/31	10.2.87.228 – 10.2.87.229	10.2.87.229
116	10.2.87.230/31	10.2.87.230 – 10.2.87.231	10.2.87.231
117	10.2.87.232/31	10.2.87.232 – 10.2.87.233	10.2.87.233
118	10.2.87.234/31	10.2.87.234 – 10.2.87.235	10.2.87.235
119	10.2.87.236/31	10.2.87.236 – 10.2.87.237	10.2.87.237
120	10.2.87.238/31	10.2.87.238 – 10.2.87.239	10.2.87.239
121	10.2.87.240/31	10.2.87.240 – 10.2.87.241	10.2.87.241
122	10.2.87.242/31	10.2.87.242 – 10.2.87.243	10.2.87.243
123	10.2.87.244/31	10.2.87.244 – 10.2.87.245	10.2.87.245
124	10.2.87.246/31	10.2.87.246 – 10.2.87.247	10.2.87.247
125	10.2.87.248/31	10.2.87.248 – 10.2.87.249	10.2.87.249
126	10.2.87.250/31	10.2.87.250 – 10.2.87.251	10.2.87.251
127	10.2.87.252/31	10.2.87.252 – 10.2.87.253	10.2.87.253
128	10.2.87.254/31	10.2.87.254 – 10.2.87.255	10.2.87.255

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 →