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)10.0.240.0/21

network10.0.240.0/21

broadcast10.0.247.255

first host10.0.240.1

last host10.0.247.254

subnet mask255.255.248.0

wildcard0.0.7.255

addresses2,048

usable hosts2,046

classA

ipcalc 10.0.240.0/21

address00001010.00000000.11110000.00000000

subnet mask11111111.11111111.11111000.00000000

network00001010.00000000.11110000.00000000

broadcast00001010.00000000.11110111.11111111

green = network part, grey = host part

hex0x0a00f000

decimal167833600

reverse dns0.240.0.10.in-addr.arpa

ipv4-mapped::ffff:a00:f000

/21 split into /30 · 512 subnets

close ×

#	network	host range	broadcast
1	10.0.240.0/30	10.0.240.1 – 10.0.240.2	10.0.240.3
2	10.0.240.4/30	10.0.240.5 – 10.0.240.6	10.0.240.7
3	10.0.240.8/30	10.0.240.9 – 10.0.240.10	10.0.240.11
4	10.0.240.12/30	10.0.240.13 – 10.0.240.14	10.0.240.15
5	10.0.240.16/30	10.0.240.17 – 10.0.240.18	10.0.240.19
6	10.0.240.20/30	10.0.240.21 – 10.0.240.22	10.0.240.23
7	10.0.240.24/30	10.0.240.25 – 10.0.240.26	10.0.240.27
8	10.0.240.28/30	10.0.240.29 – 10.0.240.30	10.0.240.31
9	10.0.240.32/30	10.0.240.33 – 10.0.240.34	10.0.240.35
10	10.0.240.36/30	10.0.240.37 – 10.0.240.38	10.0.240.39
11	10.0.240.40/30	10.0.240.41 – 10.0.240.42	10.0.240.43
12	10.0.240.44/30	10.0.240.45 – 10.0.240.46	10.0.240.47
13	10.0.240.48/30	10.0.240.49 – 10.0.240.50	10.0.240.51
14	10.0.240.52/30	10.0.240.53 – 10.0.240.54	10.0.240.55
15	10.0.240.56/30	10.0.240.57 – 10.0.240.58	10.0.240.59
16	10.0.240.60/30	10.0.240.61 – 10.0.240.62	10.0.240.63
17	10.0.240.64/30	10.0.240.65 – 10.0.240.66	10.0.240.67
18	10.0.240.68/30	10.0.240.69 – 10.0.240.70	10.0.240.71
19	10.0.240.72/30	10.0.240.73 – 10.0.240.74	10.0.240.75
20	10.0.240.76/30	10.0.240.77 – 10.0.240.78	10.0.240.79
21	10.0.240.80/30	10.0.240.81 – 10.0.240.82	10.0.240.83
22	10.0.240.84/30	10.0.240.85 – 10.0.240.86	10.0.240.87
23	10.0.240.88/30	10.0.240.89 – 10.0.240.90	10.0.240.91
24	10.0.240.92/30	10.0.240.93 – 10.0.240.94	10.0.240.95
25	10.0.240.96/30	10.0.240.97 – 10.0.240.98	10.0.240.99
26	10.0.240.100/30	10.0.240.101 – 10.0.240.102	10.0.240.103
27	10.0.240.104/30	10.0.240.105 – 10.0.240.106	10.0.240.107
28	10.0.240.108/30	10.0.240.109 – 10.0.240.110	10.0.240.111
29	10.0.240.112/30	10.0.240.113 – 10.0.240.114	10.0.240.115
30	10.0.240.116/30	10.0.240.117 – 10.0.240.118	10.0.240.119
31	10.0.240.120/30	10.0.240.121 – 10.0.240.122	10.0.240.123
32	10.0.240.124/30	10.0.240.125 – 10.0.240.126	10.0.240.127
33	10.0.240.128/30	10.0.240.129 – 10.0.240.130	10.0.240.131
34	10.0.240.132/30	10.0.240.133 – 10.0.240.134	10.0.240.135
35	10.0.240.136/30	10.0.240.137 – 10.0.240.138	10.0.240.139
36	10.0.240.140/30	10.0.240.141 – 10.0.240.142	10.0.240.143
37	10.0.240.144/30	10.0.240.145 – 10.0.240.146	10.0.240.147
38	10.0.240.148/30	10.0.240.149 – 10.0.240.150	10.0.240.151
39	10.0.240.152/30	10.0.240.153 – 10.0.240.154	10.0.240.155
40	10.0.240.156/30	10.0.240.157 – 10.0.240.158	10.0.240.159
41	10.0.240.160/30	10.0.240.161 – 10.0.240.162	10.0.240.163
42	10.0.240.164/30	10.0.240.165 – 10.0.240.166	10.0.240.167
43	10.0.240.168/30	10.0.240.169 – 10.0.240.170	10.0.240.171
44	10.0.240.172/30	10.0.240.173 – 10.0.240.174	10.0.240.175
45	10.0.240.176/30	10.0.240.177 – 10.0.240.178	10.0.240.179
46	10.0.240.180/30	10.0.240.181 – 10.0.240.182	10.0.240.183
47	10.0.240.184/30	10.0.240.185 – 10.0.240.186	10.0.240.187
48	10.0.240.188/30	10.0.240.189 – 10.0.240.190	10.0.240.191
49	10.0.240.192/30	10.0.240.193 – 10.0.240.194	10.0.240.195
50	10.0.240.196/30	10.0.240.197 – 10.0.240.198	10.0.240.199
51	10.0.240.200/30	10.0.240.201 – 10.0.240.202	10.0.240.203
52	10.0.240.204/30	10.0.240.205 – 10.0.240.206	10.0.240.207
53	10.0.240.208/30	10.0.240.209 – 10.0.240.210	10.0.240.211
54	10.0.240.212/30	10.0.240.213 – 10.0.240.214	10.0.240.215
55	10.0.240.216/30	10.0.240.217 – 10.0.240.218	10.0.240.219
56	10.0.240.220/30	10.0.240.221 – 10.0.240.222	10.0.240.223
57	10.0.240.224/30	10.0.240.225 – 10.0.240.226	10.0.240.227
58	10.0.240.228/30	10.0.240.229 – 10.0.240.230	10.0.240.231
59	10.0.240.232/30	10.0.240.233 – 10.0.240.234	10.0.240.235
60	10.0.240.236/30	10.0.240.237 – 10.0.240.238	10.0.240.239
61	10.0.240.240/30	10.0.240.241 – 10.0.240.242	10.0.240.243
62	10.0.240.244/30	10.0.240.245 – 10.0.240.246	10.0.240.247
63	10.0.240.248/30	10.0.240.249 – 10.0.240.250	10.0.240.251
64	10.0.240.252/30	10.0.240.253 – 10.0.240.254	10.0.240.255
65	10.0.241.0/30	10.0.241.1 – 10.0.241.2	10.0.241.3
66	10.0.241.4/30	10.0.241.5 – 10.0.241.6	10.0.241.7
67	10.0.241.8/30	10.0.241.9 – 10.0.241.10	10.0.241.11
68	10.0.241.12/30	10.0.241.13 – 10.0.241.14	10.0.241.15
69	10.0.241.16/30	10.0.241.17 – 10.0.241.18	10.0.241.19
70	10.0.241.20/30	10.0.241.21 – 10.0.241.22	10.0.241.23
71	10.0.241.24/30	10.0.241.25 – 10.0.241.26	10.0.241.27
72	10.0.241.28/30	10.0.241.29 – 10.0.241.30	10.0.241.31
73	10.0.241.32/30	10.0.241.33 – 10.0.241.34	10.0.241.35
74	10.0.241.36/30	10.0.241.37 – 10.0.241.38	10.0.241.39
75	10.0.241.40/30	10.0.241.41 – 10.0.241.42	10.0.241.43
76	10.0.241.44/30	10.0.241.45 – 10.0.241.46	10.0.241.47
77	10.0.241.48/30	10.0.241.49 – 10.0.241.50	10.0.241.51
78	10.0.241.52/30	10.0.241.53 – 10.0.241.54	10.0.241.55
79	10.0.241.56/30	10.0.241.57 – 10.0.241.58	10.0.241.59
80	10.0.241.60/30	10.0.241.61 – 10.0.241.62	10.0.241.63
81	10.0.241.64/30	10.0.241.65 – 10.0.241.66	10.0.241.67
82	10.0.241.68/30	10.0.241.69 – 10.0.241.70	10.0.241.71
83	10.0.241.72/30	10.0.241.73 – 10.0.241.74	10.0.241.75
84	10.0.241.76/30	10.0.241.77 – 10.0.241.78	10.0.241.79
85	10.0.241.80/30	10.0.241.81 – 10.0.241.82	10.0.241.83
86	10.0.241.84/30	10.0.241.85 – 10.0.241.86	10.0.241.87
87	10.0.241.88/30	10.0.241.89 – 10.0.241.90	10.0.241.91
88	10.0.241.92/30	10.0.241.93 – 10.0.241.94	10.0.241.95
89	10.0.241.96/30	10.0.241.97 – 10.0.241.98	10.0.241.99
90	10.0.241.100/30	10.0.241.101 – 10.0.241.102	10.0.241.103
91	10.0.241.104/30	10.0.241.105 – 10.0.241.106	10.0.241.107
92	10.0.241.108/30	10.0.241.109 – 10.0.241.110	10.0.241.111
93	10.0.241.112/30	10.0.241.113 – 10.0.241.114	10.0.241.115
94	10.0.241.116/30	10.0.241.117 – 10.0.241.118	10.0.241.119
95	10.0.241.120/30	10.0.241.121 – 10.0.241.122	10.0.241.123
96	10.0.241.124/30	10.0.241.125 – 10.0.241.126	10.0.241.127
97	10.0.241.128/30	10.0.241.129 – 10.0.241.130	10.0.241.131
98	10.0.241.132/30	10.0.241.133 – 10.0.241.134	10.0.241.135
99	10.0.241.136/30	10.0.241.137 – 10.0.241.138	10.0.241.139
100	10.0.241.140/30	10.0.241.141 – 10.0.241.142	10.0.241.143
101	10.0.241.144/30	10.0.241.145 – 10.0.241.146	10.0.241.147
102	10.0.241.148/30	10.0.241.149 – 10.0.241.150	10.0.241.151
103	10.0.241.152/30	10.0.241.153 – 10.0.241.154	10.0.241.155
104	10.0.241.156/30	10.0.241.157 – 10.0.241.158	10.0.241.159
105	10.0.241.160/30	10.0.241.161 – 10.0.241.162	10.0.241.163
106	10.0.241.164/30	10.0.241.165 – 10.0.241.166	10.0.241.167
107	10.0.241.168/30	10.0.241.169 – 10.0.241.170	10.0.241.171
108	10.0.241.172/30	10.0.241.173 – 10.0.241.174	10.0.241.175
109	10.0.241.176/30	10.0.241.177 – 10.0.241.178	10.0.241.179
110	10.0.241.180/30	10.0.241.181 – 10.0.241.182	10.0.241.183
111	10.0.241.184/30	10.0.241.185 – 10.0.241.186	10.0.241.187
112	10.0.241.188/30	10.0.241.189 – 10.0.241.190	10.0.241.191
113	10.0.241.192/30	10.0.241.193 – 10.0.241.194	10.0.241.195
114	10.0.241.196/30	10.0.241.197 – 10.0.241.198	10.0.241.199
115	10.0.241.200/30	10.0.241.201 – 10.0.241.202	10.0.241.203
116	10.0.241.204/30	10.0.241.205 – 10.0.241.206	10.0.241.207
117	10.0.241.208/30	10.0.241.209 – 10.0.241.210	10.0.241.211
118	10.0.241.212/30	10.0.241.213 – 10.0.241.214	10.0.241.215
119	10.0.241.216/30	10.0.241.217 – 10.0.241.218	10.0.241.219
120	10.0.241.220/30	10.0.241.221 – 10.0.241.222	10.0.241.223
121	10.0.241.224/30	10.0.241.225 – 10.0.241.226	10.0.241.227
122	10.0.241.228/30	10.0.241.229 – 10.0.241.230	10.0.241.231
123	10.0.241.232/30	10.0.241.233 – 10.0.241.234	10.0.241.235
124	10.0.241.236/30	10.0.241.237 – 10.0.241.238	10.0.241.239
125	10.0.241.240/30	10.0.241.241 – 10.0.241.242	10.0.241.243
126	10.0.241.244/30	10.0.241.245 – 10.0.241.246	10.0.241.247
127	10.0.241.248/30	10.0.241.249 – 10.0.241.250	10.0.241.251
128	10.0.241.252/30	10.0.241.253 – 10.0.241.254	10.0.241.255
129	10.0.242.0/30	10.0.242.1 – 10.0.242.2	10.0.242.3
130	10.0.242.4/30	10.0.242.5 – 10.0.242.6	10.0.242.7
131	10.0.242.8/30	10.0.242.9 – 10.0.242.10	10.0.242.11
132	10.0.242.12/30	10.0.242.13 – 10.0.242.14	10.0.242.15
133	10.0.242.16/30	10.0.242.17 – 10.0.242.18	10.0.242.19
134	10.0.242.20/30	10.0.242.21 – 10.0.242.22	10.0.242.23
135	10.0.242.24/30	10.0.242.25 – 10.0.242.26	10.0.242.27
136	10.0.242.28/30	10.0.242.29 – 10.0.242.30	10.0.242.31
137	10.0.242.32/30	10.0.242.33 – 10.0.242.34	10.0.242.35
138	10.0.242.36/30	10.0.242.37 – 10.0.242.38	10.0.242.39
139	10.0.242.40/30	10.0.242.41 – 10.0.242.42	10.0.242.43
140	10.0.242.44/30	10.0.242.45 – 10.0.242.46	10.0.242.47
141	10.0.242.48/30	10.0.242.49 – 10.0.242.50	10.0.242.51
142	10.0.242.52/30	10.0.242.53 – 10.0.242.54	10.0.242.55
143	10.0.242.56/30	10.0.242.57 – 10.0.242.58	10.0.242.59
144	10.0.242.60/30	10.0.242.61 – 10.0.242.62	10.0.242.63
145	10.0.242.64/30	10.0.242.65 – 10.0.242.66	10.0.242.67
146	10.0.242.68/30	10.0.242.69 – 10.0.242.70	10.0.242.71
147	10.0.242.72/30	10.0.242.73 – 10.0.242.74	10.0.242.75
148	10.0.242.76/30	10.0.242.77 – 10.0.242.78	10.0.242.79
149	10.0.242.80/30	10.0.242.81 – 10.0.242.82	10.0.242.83
150	10.0.242.84/30	10.0.242.85 – 10.0.242.86	10.0.242.87
151	10.0.242.88/30	10.0.242.89 – 10.0.242.90	10.0.242.91
152	10.0.242.92/30	10.0.242.93 – 10.0.242.94	10.0.242.95
153	10.0.242.96/30	10.0.242.97 – 10.0.242.98	10.0.242.99
154	10.0.242.100/30	10.0.242.101 – 10.0.242.102	10.0.242.103
155	10.0.242.104/30	10.0.242.105 – 10.0.242.106	10.0.242.107
156	10.0.242.108/30	10.0.242.109 – 10.0.242.110	10.0.242.111
157	10.0.242.112/30	10.0.242.113 – 10.0.242.114	10.0.242.115
158	10.0.242.116/30	10.0.242.117 – 10.0.242.118	10.0.242.119
159	10.0.242.120/30	10.0.242.121 – 10.0.242.122	10.0.242.123
160	10.0.242.124/30	10.0.242.125 – 10.0.242.126	10.0.242.127
161	10.0.242.128/30	10.0.242.129 – 10.0.242.130	10.0.242.131
162	10.0.242.132/30	10.0.242.133 – 10.0.242.134	10.0.242.135
163	10.0.242.136/30	10.0.242.137 – 10.0.242.138	10.0.242.139
164	10.0.242.140/30	10.0.242.141 – 10.0.242.142	10.0.242.143
165	10.0.242.144/30	10.0.242.145 – 10.0.242.146	10.0.242.147
166	10.0.242.148/30	10.0.242.149 – 10.0.242.150	10.0.242.151
167	10.0.242.152/30	10.0.242.153 – 10.0.242.154	10.0.242.155
168	10.0.242.156/30	10.0.242.157 – 10.0.242.158	10.0.242.159
169	10.0.242.160/30	10.0.242.161 – 10.0.242.162	10.0.242.163
170	10.0.242.164/30	10.0.242.165 – 10.0.242.166	10.0.242.167
171	10.0.242.168/30	10.0.242.169 – 10.0.242.170	10.0.242.171
172	10.0.242.172/30	10.0.242.173 – 10.0.242.174	10.0.242.175
173	10.0.242.176/30	10.0.242.177 – 10.0.242.178	10.0.242.179
174	10.0.242.180/30	10.0.242.181 – 10.0.242.182	10.0.242.183
175	10.0.242.184/30	10.0.242.185 – 10.0.242.186	10.0.242.187
176	10.0.242.188/30	10.0.242.189 – 10.0.242.190	10.0.242.191
177	10.0.242.192/30	10.0.242.193 – 10.0.242.194	10.0.242.195
178	10.0.242.196/30	10.0.242.197 – 10.0.242.198	10.0.242.199
179	10.0.242.200/30	10.0.242.201 – 10.0.242.202	10.0.242.203
180	10.0.242.204/30	10.0.242.205 – 10.0.242.206	10.0.242.207
181	10.0.242.208/30	10.0.242.209 – 10.0.242.210	10.0.242.211
182	10.0.242.212/30	10.0.242.213 – 10.0.242.214	10.0.242.215
183	10.0.242.216/30	10.0.242.217 – 10.0.242.218	10.0.242.219
184	10.0.242.220/30	10.0.242.221 – 10.0.242.222	10.0.242.223
185	10.0.242.224/30	10.0.242.225 – 10.0.242.226	10.0.242.227
186	10.0.242.228/30	10.0.242.229 – 10.0.242.230	10.0.242.231
187	10.0.242.232/30	10.0.242.233 – 10.0.242.234	10.0.242.235
188	10.0.242.236/30	10.0.242.237 – 10.0.242.238	10.0.242.239
189	10.0.242.240/30	10.0.242.241 – 10.0.242.242	10.0.242.243
190	10.0.242.244/30	10.0.242.245 – 10.0.242.246	10.0.242.247
191	10.0.242.248/30	10.0.242.249 – 10.0.242.250	10.0.242.251
192	10.0.242.252/30	10.0.242.253 – 10.0.242.254	10.0.242.255
193	10.0.243.0/30	10.0.243.1 – 10.0.243.2	10.0.243.3
194	10.0.243.4/30	10.0.243.5 – 10.0.243.6	10.0.243.7
195	10.0.243.8/30	10.0.243.9 – 10.0.243.10	10.0.243.11
196	10.0.243.12/30	10.0.243.13 – 10.0.243.14	10.0.243.15
197	10.0.243.16/30	10.0.243.17 – 10.0.243.18	10.0.243.19
198	10.0.243.20/30	10.0.243.21 – 10.0.243.22	10.0.243.23
199	10.0.243.24/30	10.0.243.25 – 10.0.243.26	10.0.243.27
200	10.0.243.28/30	10.0.243.29 – 10.0.243.30	10.0.243.31
201	10.0.243.32/30	10.0.243.33 – 10.0.243.34	10.0.243.35
202	10.0.243.36/30	10.0.243.37 – 10.0.243.38	10.0.243.39
203	10.0.243.40/30	10.0.243.41 – 10.0.243.42	10.0.243.43
204	10.0.243.44/30	10.0.243.45 – 10.0.243.46	10.0.243.47
205	10.0.243.48/30	10.0.243.49 – 10.0.243.50	10.0.243.51
206	10.0.243.52/30	10.0.243.53 – 10.0.243.54	10.0.243.55
207	10.0.243.56/30	10.0.243.57 – 10.0.243.58	10.0.243.59
208	10.0.243.60/30	10.0.243.61 – 10.0.243.62	10.0.243.63
209	10.0.243.64/30	10.0.243.65 – 10.0.243.66	10.0.243.67
210	10.0.243.68/30	10.0.243.69 – 10.0.243.70	10.0.243.71
211	10.0.243.72/30	10.0.243.73 – 10.0.243.74	10.0.243.75
212	10.0.243.76/30	10.0.243.77 – 10.0.243.78	10.0.243.79
213	10.0.243.80/30	10.0.243.81 – 10.0.243.82	10.0.243.83
214	10.0.243.84/30	10.0.243.85 – 10.0.243.86	10.0.243.87
215	10.0.243.88/30	10.0.243.89 – 10.0.243.90	10.0.243.91
216	10.0.243.92/30	10.0.243.93 – 10.0.243.94	10.0.243.95
217	10.0.243.96/30	10.0.243.97 – 10.0.243.98	10.0.243.99
218	10.0.243.100/30	10.0.243.101 – 10.0.243.102	10.0.243.103
219	10.0.243.104/30	10.0.243.105 – 10.0.243.106	10.0.243.107
220	10.0.243.108/30	10.0.243.109 – 10.0.243.110	10.0.243.111
221	10.0.243.112/30	10.0.243.113 – 10.0.243.114	10.0.243.115
222	10.0.243.116/30	10.0.243.117 – 10.0.243.118	10.0.243.119
223	10.0.243.120/30	10.0.243.121 – 10.0.243.122	10.0.243.123
224	10.0.243.124/30	10.0.243.125 – 10.0.243.126	10.0.243.127
225	10.0.243.128/30	10.0.243.129 – 10.0.243.130	10.0.243.131
226	10.0.243.132/30	10.0.243.133 – 10.0.243.134	10.0.243.135
227	10.0.243.136/30	10.0.243.137 – 10.0.243.138	10.0.243.139
228	10.0.243.140/30	10.0.243.141 – 10.0.243.142	10.0.243.143
229	10.0.243.144/30	10.0.243.145 – 10.0.243.146	10.0.243.147
230	10.0.243.148/30	10.0.243.149 – 10.0.243.150	10.0.243.151
231	10.0.243.152/30	10.0.243.153 – 10.0.243.154	10.0.243.155
232	10.0.243.156/30	10.0.243.157 – 10.0.243.158	10.0.243.159
233	10.0.243.160/30	10.0.243.161 – 10.0.243.162	10.0.243.163
234	10.0.243.164/30	10.0.243.165 – 10.0.243.166	10.0.243.167
235	10.0.243.168/30	10.0.243.169 – 10.0.243.170	10.0.243.171
236	10.0.243.172/30	10.0.243.173 – 10.0.243.174	10.0.243.175
237	10.0.243.176/30	10.0.243.177 – 10.0.243.178	10.0.243.179
238	10.0.243.180/30	10.0.243.181 – 10.0.243.182	10.0.243.183
239	10.0.243.184/30	10.0.243.185 – 10.0.243.186	10.0.243.187
240	10.0.243.188/30	10.0.243.189 – 10.0.243.190	10.0.243.191
241	10.0.243.192/30	10.0.243.193 – 10.0.243.194	10.0.243.195
242	10.0.243.196/30	10.0.243.197 – 10.0.243.198	10.0.243.199
243	10.0.243.200/30	10.0.243.201 – 10.0.243.202	10.0.243.203
244	10.0.243.204/30	10.0.243.205 – 10.0.243.206	10.0.243.207
245	10.0.243.208/30	10.0.243.209 – 10.0.243.210	10.0.243.211
246	10.0.243.212/30	10.0.243.213 – 10.0.243.214	10.0.243.215
247	10.0.243.216/30	10.0.243.217 – 10.0.243.218	10.0.243.219
248	10.0.243.220/30	10.0.243.221 – 10.0.243.222	10.0.243.223
249	10.0.243.224/30	10.0.243.225 – 10.0.243.226	10.0.243.227
250	10.0.243.228/30	10.0.243.229 – 10.0.243.230	10.0.243.231
251	10.0.243.232/30	10.0.243.233 – 10.0.243.234	10.0.243.235
252	10.0.243.236/30	10.0.243.237 – 10.0.243.238	10.0.243.239
253	10.0.243.240/30	10.0.243.241 – 10.0.243.242	10.0.243.243
254	10.0.243.244/30	10.0.243.245 – 10.0.243.246	10.0.243.247
255	10.0.243.248/30	10.0.243.249 – 10.0.243.250	10.0.243.251
256	10.0.243.252/30	10.0.243.253 – 10.0.243.254	10.0.243.255

showing 256 of 512

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 /21
/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	1
/22	255.255.252.0	1,024	1,022	2 split →
/23	255.255.254.0	512	510	4 split →
/24	255.255.255.0	256	254	8 split →
/25	255.255.255.128	128	126	16 split →
/26	255.255.255.192	64	62	32 split →
/27	255.255.255.224	32	30	64 split →
/28	255.255.255.240	16	14	128 split →
/29	255.255.255.248	8	6	256 split →
/30	255.255.255.252	4	2	512 split →
/31	255.255.255.254	2	2	1,024 split →
/32	255.255.255.255	1	1	2,048 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 →