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)10.78.121.0/24

network10.78.121.0/24

broadcast10.78.121.255

first host10.78.121.1

last host10.78.121.254

subnet mask255.255.255.0

wildcard0.0.0.255

addresses256

usable hosts254

classA

ipcalc 10.78.121.0/24

address00001010.01001110.01111001.00000000

subnet mask11111111.11111111.11111111.00000000

network00001010.01001110.01111001.00000000

broadcast00001010.01001110.01111001.11111111

green = network part, grey = host part

hex0x0a4e7900

decimal172914944

reverse dns0.121.78.10.in-addr.arpa

ipv4-mapped::ffff:a4e:7900

/24 split into /31 · 128 subnets

close ×

#	network	host range	broadcast
1	10.78.121.0/31	10.78.121.0 – 10.78.121.1	10.78.121.1
2	10.78.121.2/31	10.78.121.2 – 10.78.121.3	10.78.121.3
3	10.78.121.4/31	10.78.121.4 – 10.78.121.5	10.78.121.5
4	10.78.121.6/31	10.78.121.6 – 10.78.121.7	10.78.121.7
5	10.78.121.8/31	10.78.121.8 – 10.78.121.9	10.78.121.9
6	10.78.121.10/31	10.78.121.10 – 10.78.121.11	10.78.121.11
7	10.78.121.12/31	10.78.121.12 – 10.78.121.13	10.78.121.13
8	10.78.121.14/31	10.78.121.14 – 10.78.121.15	10.78.121.15
9	10.78.121.16/31	10.78.121.16 – 10.78.121.17	10.78.121.17
10	10.78.121.18/31	10.78.121.18 – 10.78.121.19	10.78.121.19
11	10.78.121.20/31	10.78.121.20 – 10.78.121.21	10.78.121.21
12	10.78.121.22/31	10.78.121.22 – 10.78.121.23	10.78.121.23
13	10.78.121.24/31	10.78.121.24 – 10.78.121.25	10.78.121.25
14	10.78.121.26/31	10.78.121.26 – 10.78.121.27	10.78.121.27
15	10.78.121.28/31	10.78.121.28 – 10.78.121.29	10.78.121.29
16	10.78.121.30/31	10.78.121.30 – 10.78.121.31	10.78.121.31
17	10.78.121.32/31	10.78.121.32 – 10.78.121.33	10.78.121.33
18	10.78.121.34/31	10.78.121.34 – 10.78.121.35	10.78.121.35
19	10.78.121.36/31	10.78.121.36 – 10.78.121.37	10.78.121.37
20	10.78.121.38/31	10.78.121.38 – 10.78.121.39	10.78.121.39
21	10.78.121.40/31	10.78.121.40 – 10.78.121.41	10.78.121.41
22	10.78.121.42/31	10.78.121.42 – 10.78.121.43	10.78.121.43
23	10.78.121.44/31	10.78.121.44 – 10.78.121.45	10.78.121.45
24	10.78.121.46/31	10.78.121.46 – 10.78.121.47	10.78.121.47
25	10.78.121.48/31	10.78.121.48 – 10.78.121.49	10.78.121.49
26	10.78.121.50/31	10.78.121.50 – 10.78.121.51	10.78.121.51
27	10.78.121.52/31	10.78.121.52 – 10.78.121.53	10.78.121.53
28	10.78.121.54/31	10.78.121.54 – 10.78.121.55	10.78.121.55
29	10.78.121.56/31	10.78.121.56 – 10.78.121.57	10.78.121.57
30	10.78.121.58/31	10.78.121.58 – 10.78.121.59	10.78.121.59
31	10.78.121.60/31	10.78.121.60 – 10.78.121.61	10.78.121.61
32	10.78.121.62/31	10.78.121.62 – 10.78.121.63	10.78.121.63
33	10.78.121.64/31	10.78.121.64 – 10.78.121.65	10.78.121.65
34	10.78.121.66/31	10.78.121.66 – 10.78.121.67	10.78.121.67
35	10.78.121.68/31	10.78.121.68 – 10.78.121.69	10.78.121.69
36	10.78.121.70/31	10.78.121.70 – 10.78.121.71	10.78.121.71
37	10.78.121.72/31	10.78.121.72 – 10.78.121.73	10.78.121.73
38	10.78.121.74/31	10.78.121.74 – 10.78.121.75	10.78.121.75
39	10.78.121.76/31	10.78.121.76 – 10.78.121.77	10.78.121.77
40	10.78.121.78/31	10.78.121.78 – 10.78.121.79	10.78.121.79
41	10.78.121.80/31	10.78.121.80 – 10.78.121.81	10.78.121.81
42	10.78.121.82/31	10.78.121.82 – 10.78.121.83	10.78.121.83
43	10.78.121.84/31	10.78.121.84 – 10.78.121.85	10.78.121.85
44	10.78.121.86/31	10.78.121.86 – 10.78.121.87	10.78.121.87
45	10.78.121.88/31	10.78.121.88 – 10.78.121.89	10.78.121.89
46	10.78.121.90/31	10.78.121.90 – 10.78.121.91	10.78.121.91
47	10.78.121.92/31	10.78.121.92 – 10.78.121.93	10.78.121.93
48	10.78.121.94/31	10.78.121.94 – 10.78.121.95	10.78.121.95
49	10.78.121.96/31	10.78.121.96 – 10.78.121.97	10.78.121.97
50	10.78.121.98/31	10.78.121.98 – 10.78.121.99	10.78.121.99
51	10.78.121.100/31	10.78.121.100 – 10.78.121.101	10.78.121.101
52	10.78.121.102/31	10.78.121.102 – 10.78.121.103	10.78.121.103
53	10.78.121.104/31	10.78.121.104 – 10.78.121.105	10.78.121.105
54	10.78.121.106/31	10.78.121.106 – 10.78.121.107	10.78.121.107
55	10.78.121.108/31	10.78.121.108 – 10.78.121.109	10.78.121.109
56	10.78.121.110/31	10.78.121.110 – 10.78.121.111	10.78.121.111
57	10.78.121.112/31	10.78.121.112 – 10.78.121.113	10.78.121.113
58	10.78.121.114/31	10.78.121.114 – 10.78.121.115	10.78.121.115
59	10.78.121.116/31	10.78.121.116 – 10.78.121.117	10.78.121.117
60	10.78.121.118/31	10.78.121.118 – 10.78.121.119	10.78.121.119
61	10.78.121.120/31	10.78.121.120 – 10.78.121.121	10.78.121.121
62	10.78.121.122/31	10.78.121.122 – 10.78.121.123	10.78.121.123
63	10.78.121.124/31	10.78.121.124 – 10.78.121.125	10.78.121.125
64	10.78.121.126/31	10.78.121.126 – 10.78.121.127	10.78.121.127
65	10.78.121.128/31	10.78.121.128 – 10.78.121.129	10.78.121.129
66	10.78.121.130/31	10.78.121.130 – 10.78.121.131	10.78.121.131
67	10.78.121.132/31	10.78.121.132 – 10.78.121.133	10.78.121.133
68	10.78.121.134/31	10.78.121.134 – 10.78.121.135	10.78.121.135
69	10.78.121.136/31	10.78.121.136 – 10.78.121.137	10.78.121.137
70	10.78.121.138/31	10.78.121.138 – 10.78.121.139	10.78.121.139
71	10.78.121.140/31	10.78.121.140 – 10.78.121.141	10.78.121.141
72	10.78.121.142/31	10.78.121.142 – 10.78.121.143	10.78.121.143
73	10.78.121.144/31	10.78.121.144 – 10.78.121.145	10.78.121.145
74	10.78.121.146/31	10.78.121.146 – 10.78.121.147	10.78.121.147
75	10.78.121.148/31	10.78.121.148 – 10.78.121.149	10.78.121.149
76	10.78.121.150/31	10.78.121.150 – 10.78.121.151	10.78.121.151
77	10.78.121.152/31	10.78.121.152 – 10.78.121.153	10.78.121.153
78	10.78.121.154/31	10.78.121.154 – 10.78.121.155	10.78.121.155
79	10.78.121.156/31	10.78.121.156 – 10.78.121.157	10.78.121.157
80	10.78.121.158/31	10.78.121.158 – 10.78.121.159	10.78.121.159
81	10.78.121.160/31	10.78.121.160 – 10.78.121.161	10.78.121.161
82	10.78.121.162/31	10.78.121.162 – 10.78.121.163	10.78.121.163
83	10.78.121.164/31	10.78.121.164 – 10.78.121.165	10.78.121.165
84	10.78.121.166/31	10.78.121.166 – 10.78.121.167	10.78.121.167
85	10.78.121.168/31	10.78.121.168 – 10.78.121.169	10.78.121.169
86	10.78.121.170/31	10.78.121.170 – 10.78.121.171	10.78.121.171
87	10.78.121.172/31	10.78.121.172 – 10.78.121.173	10.78.121.173
88	10.78.121.174/31	10.78.121.174 – 10.78.121.175	10.78.121.175
89	10.78.121.176/31	10.78.121.176 – 10.78.121.177	10.78.121.177
90	10.78.121.178/31	10.78.121.178 – 10.78.121.179	10.78.121.179
91	10.78.121.180/31	10.78.121.180 – 10.78.121.181	10.78.121.181
92	10.78.121.182/31	10.78.121.182 – 10.78.121.183	10.78.121.183
93	10.78.121.184/31	10.78.121.184 – 10.78.121.185	10.78.121.185
94	10.78.121.186/31	10.78.121.186 – 10.78.121.187	10.78.121.187
95	10.78.121.188/31	10.78.121.188 – 10.78.121.189	10.78.121.189
96	10.78.121.190/31	10.78.121.190 – 10.78.121.191	10.78.121.191
97	10.78.121.192/31	10.78.121.192 – 10.78.121.193	10.78.121.193
98	10.78.121.194/31	10.78.121.194 – 10.78.121.195	10.78.121.195
99	10.78.121.196/31	10.78.121.196 – 10.78.121.197	10.78.121.197
100	10.78.121.198/31	10.78.121.198 – 10.78.121.199	10.78.121.199
101	10.78.121.200/31	10.78.121.200 – 10.78.121.201	10.78.121.201
102	10.78.121.202/31	10.78.121.202 – 10.78.121.203	10.78.121.203
103	10.78.121.204/31	10.78.121.204 – 10.78.121.205	10.78.121.205
104	10.78.121.206/31	10.78.121.206 – 10.78.121.207	10.78.121.207
105	10.78.121.208/31	10.78.121.208 – 10.78.121.209	10.78.121.209
106	10.78.121.210/31	10.78.121.210 – 10.78.121.211	10.78.121.211
107	10.78.121.212/31	10.78.121.212 – 10.78.121.213	10.78.121.213
108	10.78.121.214/31	10.78.121.214 – 10.78.121.215	10.78.121.215
109	10.78.121.216/31	10.78.121.216 – 10.78.121.217	10.78.121.217
110	10.78.121.218/31	10.78.121.218 – 10.78.121.219	10.78.121.219
111	10.78.121.220/31	10.78.121.220 – 10.78.121.221	10.78.121.221
112	10.78.121.222/31	10.78.121.222 – 10.78.121.223	10.78.121.223
113	10.78.121.224/31	10.78.121.224 – 10.78.121.225	10.78.121.225
114	10.78.121.226/31	10.78.121.226 – 10.78.121.227	10.78.121.227
115	10.78.121.228/31	10.78.121.228 – 10.78.121.229	10.78.121.229
116	10.78.121.230/31	10.78.121.230 – 10.78.121.231	10.78.121.231
117	10.78.121.232/31	10.78.121.232 – 10.78.121.233	10.78.121.233
118	10.78.121.234/31	10.78.121.234 – 10.78.121.235	10.78.121.235
119	10.78.121.236/31	10.78.121.236 – 10.78.121.237	10.78.121.237
120	10.78.121.238/31	10.78.121.238 – 10.78.121.239	10.78.121.239
121	10.78.121.240/31	10.78.121.240 – 10.78.121.241	10.78.121.241
122	10.78.121.242/31	10.78.121.242 – 10.78.121.243	10.78.121.243
123	10.78.121.244/31	10.78.121.244 – 10.78.121.245	10.78.121.245
124	10.78.121.246/31	10.78.121.246 – 10.78.121.247	10.78.121.247
125	10.78.121.248/31	10.78.121.248 – 10.78.121.249	10.78.121.249
126	10.78.121.250/31	10.78.121.250 – 10.78.121.251	10.78.121.251
127	10.78.121.252/31	10.78.121.252 – 10.78.121.253	10.78.121.253
128	10.78.121.254/31	10.78.121.254 – 10.78.121.255	10.78.121.255

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 →