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)10.5.16.0/21

network10.5.16.0/21

broadcast10.5.23.255

first host10.5.16.1

last host10.5.23.254

subnet mask255.255.248.0

wildcard0.0.7.255

addresses2,048

usable hosts2,046

classA

ipcalc 10.5.16.0/21

address00001010.00000101.00010000.00000000

subnet mask11111111.11111111.11111000.00000000

network00001010.00000101.00010000.00000000

broadcast00001010.00000101.00010111.11111111

green = network part, grey = host part

hex0x0a051000

decimal168103936

reverse dns0.16.5.10.in-addr.arpa

ipv4-mapped::ffff:a05:1000

/21 split into /30 · 512 subnets

close ×

#	network	host range	broadcast
1	10.5.16.0/30	10.5.16.1 – 10.5.16.2	10.5.16.3
2	10.5.16.4/30	10.5.16.5 – 10.5.16.6	10.5.16.7
3	10.5.16.8/30	10.5.16.9 – 10.5.16.10	10.5.16.11
4	10.5.16.12/30	10.5.16.13 – 10.5.16.14	10.5.16.15
5	10.5.16.16/30	10.5.16.17 – 10.5.16.18	10.5.16.19
6	10.5.16.20/30	10.5.16.21 – 10.5.16.22	10.5.16.23
7	10.5.16.24/30	10.5.16.25 – 10.5.16.26	10.5.16.27
8	10.5.16.28/30	10.5.16.29 – 10.5.16.30	10.5.16.31
9	10.5.16.32/30	10.5.16.33 – 10.5.16.34	10.5.16.35
10	10.5.16.36/30	10.5.16.37 – 10.5.16.38	10.5.16.39
11	10.5.16.40/30	10.5.16.41 – 10.5.16.42	10.5.16.43
12	10.5.16.44/30	10.5.16.45 – 10.5.16.46	10.5.16.47
13	10.5.16.48/30	10.5.16.49 – 10.5.16.50	10.5.16.51
14	10.5.16.52/30	10.5.16.53 – 10.5.16.54	10.5.16.55
15	10.5.16.56/30	10.5.16.57 – 10.5.16.58	10.5.16.59
16	10.5.16.60/30	10.5.16.61 – 10.5.16.62	10.5.16.63
17	10.5.16.64/30	10.5.16.65 – 10.5.16.66	10.5.16.67
18	10.5.16.68/30	10.5.16.69 – 10.5.16.70	10.5.16.71
19	10.5.16.72/30	10.5.16.73 – 10.5.16.74	10.5.16.75
20	10.5.16.76/30	10.5.16.77 – 10.5.16.78	10.5.16.79
21	10.5.16.80/30	10.5.16.81 – 10.5.16.82	10.5.16.83
22	10.5.16.84/30	10.5.16.85 – 10.5.16.86	10.5.16.87
23	10.5.16.88/30	10.5.16.89 – 10.5.16.90	10.5.16.91
24	10.5.16.92/30	10.5.16.93 – 10.5.16.94	10.5.16.95
25	10.5.16.96/30	10.5.16.97 – 10.5.16.98	10.5.16.99
26	10.5.16.100/30	10.5.16.101 – 10.5.16.102	10.5.16.103
27	10.5.16.104/30	10.5.16.105 – 10.5.16.106	10.5.16.107
28	10.5.16.108/30	10.5.16.109 – 10.5.16.110	10.5.16.111
29	10.5.16.112/30	10.5.16.113 – 10.5.16.114	10.5.16.115
30	10.5.16.116/30	10.5.16.117 – 10.5.16.118	10.5.16.119
31	10.5.16.120/30	10.5.16.121 – 10.5.16.122	10.5.16.123
32	10.5.16.124/30	10.5.16.125 – 10.5.16.126	10.5.16.127
33	10.5.16.128/30	10.5.16.129 – 10.5.16.130	10.5.16.131
34	10.5.16.132/30	10.5.16.133 – 10.5.16.134	10.5.16.135
35	10.5.16.136/30	10.5.16.137 – 10.5.16.138	10.5.16.139
36	10.5.16.140/30	10.5.16.141 – 10.5.16.142	10.5.16.143
37	10.5.16.144/30	10.5.16.145 – 10.5.16.146	10.5.16.147
38	10.5.16.148/30	10.5.16.149 – 10.5.16.150	10.5.16.151
39	10.5.16.152/30	10.5.16.153 – 10.5.16.154	10.5.16.155
40	10.5.16.156/30	10.5.16.157 – 10.5.16.158	10.5.16.159
41	10.5.16.160/30	10.5.16.161 – 10.5.16.162	10.5.16.163
42	10.5.16.164/30	10.5.16.165 – 10.5.16.166	10.5.16.167
43	10.5.16.168/30	10.5.16.169 – 10.5.16.170	10.5.16.171
44	10.5.16.172/30	10.5.16.173 – 10.5.16.174	10.5.16.175
45	10.5.16.176/30	10.5.16.177 – 10.5.16.178	10.5.16.179
46	10.5.16.180/30	10.5.16.181 – 10.5.16.182	10.5.16.183
47	10.5.16.184/30	10.5.16.185 – 10.5.16.186	10.5.16.187
48	10.5.16.188/30	10.5.16.189 – 10.5.16.190	10.5.16.191
49	10.5.16.192/30	10.5.16.193 – 10.5.16.194	10.5.16.195
50	10.5.16.196/30	10.5.16.197 – 10.5.16.198	10.5.16.199
51	10.5.16.200/30	10.5.16.201 – 10.5.16.202	10.5.16.203
52	10.5.16.204/30	10.5.16.205 – 10.5.16.206	10.5.16.207
53	10.5.16.208/30	10.5.16.209 – 10.5.16.210	10.5.16.211
54	10.5.16.212/30	10.5.16.213 – 10.5.16.214	10.5.16.215
55	10.5.16.216/30	10.5.16.217 – 10.5.16.218	10.5.16.219
56	10.5.16.220/30	10.5.16.221 – 10.5.16.222	10.5.16.223
57	10.5.16.224/30	10.5.16.225 – 10.5.16.226	10.5.16.227
58	10.5.16.228/30	10.5.16.229 – 10.5.16.230	10.5.16.231
59	10.5.16.232/30	10.5.16.233 – 10.5.16.234	10.5.16.235
60	10.5.16.236/30	10.5.16.237 – 10.5.16.238	10.5.16.239
61	10.5.16.240/30	10.5.16.241 – 10.5.16.242	10.5.16.243
62	10.5.16.244/30	10.5.16.245 – 10.5.16.246	10.5.16.247
63	10.5.16.248/30	10.5.16.249 – 10.5.16.250	10.5.16.251
64	10.5.16.252/30	10.5.16.253 – 10.5.16.254	10.5.16.255
65	10.5.17.0/30	10.5.17.1 – 10.5.17.2	10.5.17.3
66	10.5.17.4/30	10.5.17.5 – 10.5.17.6	10.5.17.7
67	10.5.17.8/30	10.5.17.9 – 10.5.17.10	10.5.17.11
68	10.5.17.12/30	10.5.17.13 – 10.5.17.14	10.5.17.15
69	10.5.17.16/30	10.5.17.17 – 10.5.17.18	10.5.17.19
70	10.5.17.20/30	10.5.17.21 – 10.5.17.22	10.5.17.23
71	10.5.17.24/30	10.5.17.25 – 10.5.17.26	10.5.17.27
72	10.5.17.28/30	10.5.17.29 – 10.5.17.30	10.5.17.31
73	10.5.17.32/30	10.5.17.33 – 10.5.17.34	10.5.17.35
74	10.5.17.36/30	10.5.17.37 – 10.5.17.38	10.5.17.39
75	10.5.17.40/30	10.5.17.41 – 10.5.17.42	10.5.17.43
76	10.5.17.44/30	10.5.17.45 – 10.5.17.46	10.5.17.47
77	10.5.17.48/30	10.5.17.49 – 10.5.17.50	10.5.17.51
78	10.5.17.52/30	10.5.17.53 – 10.5.17.54	10.5.17.55
79	10.5.17.56/30	10.5.17.57 – 10.5.17.58	10.5.17.59
80	10.5.17.60/30	10.5.17.61 – 10.5.17.62	10.5.17.63
81	10.5.17.64/30	10.5.17.65 – 10.5.17.66	10.5.17.67
82	10.5.17.68/30	10.5.17.69 – 10.5.17.70	10.5.17.71
83	10.5.17.72/30	10.5.17.73 – 10.5.17.74	10.5.17.75
84	10.5.17.76/30	10.5.17.77 – 10.5.17.78	10.5.17.79
85	10.5.17.80/30	10.5.17.81 – 10.5.17.82	10.5.17.83
86	10.5.17.84/30	10.5.17.85 – 10.5.17.86	10.5.17.87
87	10.5.17.88/30	10.5.17.89 – 10.5.17.90	10.5.17.91
88	10.5.17.92/30	10.5.17.93 – 10.5.17.94	10.5.17.95
89	10.5.17.96/30	10.5.17.97 – 10.5.17.98	10.5.17.99
90	10.5.17.100/30	10.5.17.101 – 10.5.17.102	10.5.17.103
91	10.5.17.104/30	10.5.17.105 – 10.5.17.106	10.5.17.107
92	10.5.17.108/30	10.5.17.109 – 10.5.17.110	10.5.17.111
93	10.5.17.112/30	10.5.17.113 – 10.5.17.114	10.5.17.115
94	10.5.17.116/30	10.5.17.117 – 10.5.17.118	10.5.17.119
95	10.5.17.120/30	10.5.17.121 – 10.5.17.122	10.5.17.123
96	10.5.17.124/30	10.5.17.125 – 10.5.17.126	10.5.17.127
97	10.5.17.128/30	10.5.17.129 – 10.5.17.130	10.5.17.131
98	10.5.17.132/30	10.5.17.133 – 10.5.17.134	10.5.17.135
99	10.5.17.136/30	10.5.17.137 – 10.5.17.138	10.5.17.139
100	10.5.17.140/30	10.5.17.141 – 10.5.17.142	10.5.17.143
101	10.5.17.144/30	10.5.17.145 – 10.5.17.146	10.5.17.147
102	10.5.17.148/30	10.5.17.149 – 10.5.17.150	10.5.17.151
103	10.5.17.152/30	10.5.17.153 – 10.5.17.154	10.5.17.155
104	10.5.17.156/30	10.5.17.157 – 10.5.17.158	10.5.17.159
105	10.5.17.160/30	10.5.17.161 – 10.5.17.162	10.5.17.163
106	10.5.17.164/30	10.5.17.165 – 10.5.17.166	10.5.17.167
107	10.5.17.168/30	10.5.17.169 – 10.5.17.170	10.5.17.171
108	10.5.17.172/30	10.5.17.173 – 10.5.17.174	10.5.17.175
109	10.5.17.176/30	10.5.17.177 – 10.5.17.178	10.5.17.179
110	10.5.17.180/30	10.5.17.181 – 10.5.17.182	10.5.17.183
111	10.5.17.184/30	10.5.17.185 – 10.5.17.186	10.5.17.187
112	10.5.17.188/30	10.5.17.189 – 10.5.17.190	10.5.17.191
113	10.5.17.192/30	10.5.17.193 – 10.5.17.194	10.5.17.195
114	10.5.17.196/30	10.5.17.197 – 10.5.17.198	10.5.17.199
115	10.5.17.200/30	10.5.17.201 – 10.5.17.202	10.5.17.203
116	10.5.17.204/30	10.5.17.205 – 10.5.17.206	10.5.17.207
117	10.5.17.208/30	10.5.17.209 – 10.5.17.210	10.5.17.211
118	10.5.17.212/30	10.5.17.213 – 10.5.17.214	10.5.17.215
119	10.5.17.216/30	10.5.17.217 – 10.5.17.218	10.5.17.219
120	10.5.17.220/30	10.5.17.221 – 10.5.17.222	10.5.17.223
121	10.5.17.224/30	10.5.17.225 – 10.5.17.226	10.5.17.227
122	10.5.17.228/30	10.5.17.229 – 10.5.17.230	10.5.17.231
123	10.5.17.232/30	10.5.17.233 – 10.5.17.234	10.5.17.235
124	10.5.17.236/30	10.5.17.237 – 10.5.17.238	10.5.17.239
125	10.5.17.240/30	10.5.17.241 – 10.5.17.242	10.5.17.243
126	10.5.17.244/30	10.5.17.245 – 10.5.17.246	10.5.17.247
127	10.5.17.248/30	10.5.17.249 – 10.5.17.250	10.5.17.251
128	10.5.17.252/30	10.5.17.253 – 10.5.17.254	10.5.17.255
129	10.5.18.0/30	10.5.18.1 – 10.5.18.2	10.5.18.3
130	10.5.18.4/30	10.5.18.5 – 10.5.18.6	10.5.18.7
131	10.5.18.8/30	10.5.18.9 – 10.5.18.10	10.5.18.11
132	10.5.18.12/30	10.5.18.13 – 10.5.18.14	10.5.18.15
133	10.5.18.16/30	10.5.18.17 – 10.5.18.18	10.5.18.19
134	10.5.18.20/30	10.5.18.21 – 10.5.18.22	10.5.18.23
135	10.5.18.24/30	10.5.18.25 – 10.5.18.26	10.5.18.27
136	10.5.18.28/30	10.5.18.29 – 10.5.18.30	10.5.18.31
137	10.5.18.32/30	10.5.18.33 – 10.5.18.34	10.5.18.35
138	10.5.18.36/30	10.5.18.37 – 10.5.18.38	10.5.18.39
139	10.5.18.40/30	10.5.18.41 – 10.5.18.42	10.5.18.43
140	10.5.18.44/30	10.5.18.45 – 10.5.18.46	10.5.18.47
141	10.5.18.48/30	10.5.18.49 – 10.5.18.50	10.5.18.51
142	10.5.18.52/30	10.5.18.53 – 10.5.18.54	10.5.18.55
143	10.5.18.56/30	10.5.18.57 – 10.5.18.58	10.5.18.59
144	10.5.18.60/30	10.5.18.61 – 10.5.18.62	10.5.18.63
145	10.5.18.64/30	10.5.18.65 – 10.5.18.66	10.5.18.67
146	10.5.18.68/30	10.5.18.69 – 10.5.18.70	10.5.18.71
147	10.5.18.72/30	10.5.18.73 – 10.5.18.74	10.5.18.75
148	10.5.18.76/30	10.5.18.77 – 10.5.18.78	10.5.18.79
149	10.5.18.80/30	10.5.18.81 – 10.5.18.82	10.5.18.83
150	10.5.18.84/30	10.5.18.85 – 10.5.18.86	10.5.18.87
151	10.5.18.88/30	10.5.18.89 – 10.5.18.90	10.5.18.91
152	10.5.18.92/30	10.5.18.93 – 10.5.18.94	10.5.18.95
153	10.5.18.96/30	10.5.18.97 – 10.5.18.98	10.5.18.99
154	10.5.18.100/30	10.5.18.101 – 10.5.18.102	10.5.18.103
155	10.5.18.104/30	10.5.18.105 – 10.5.18.106	10.5.18.107
156	10.5.18.108/30	10.5.18.109 – 10.5.18.110	10.5.18.111
157	10.5.18.112/30	10.5.18.113 – 10.5.18.114	10.5.18.115
158	10.5.18.116/30	10.5.18.117 – 10.5.18.118	10.5.18.119
159	10.5.18.120/30	10.5.18.121 – 10.5.18.122	10.5.18.123
160	10.5.18.124/30	10.5.18.125 – 10.5.18.126	10.5.18.127
161	10.5.18.128/30	10.5.18.129 – 10.5.18.130	10.5.18.131
162	10.5.18.132/30	10.5.18.133 – 10.5.18.134	10.5.18.135
163	10.5.18.136/30	10.5.18.137 – 10.5.18.138	10.5.18.139
164	10.5.18.140/30	10.5.18.141 – 10.5.18.142	10.5.18.143
165	10.5.18.144/30	10.5.18.145 – 10.5.18.146	10.5.18.147
166	10.5.18.148/30	10.5.18.149 – 10.5.18.150	10.5.18.151
167	10.5.18.152/30	10.5.18.153 – 10.5.18.154	10.5.18.155
168	10.5.18.156/30	10.5.18.157 – 10.5.18.158	10.5.18.159
169	10.5.18.160/30	10.5.18.161 – 10.5.18.162	10.5.18.163
170	10.5.18.164/30	10.5.18.165 – 10.5.18.166	10.5.18.167
171	10.5.18.168/30	10.5.18.169 – 10.5.18.170	10.5.18.171
172	10.5.18.172/30	10.5.18.173 – 10.5.18.174	10.5.18.175
173	10.5.18.176/30	10.5.18.177 – 10.5.18.178	10.5.18.179
174	10.5.18.180/30	10.5.18.181 – 10.5.18.182	10.5.18.183
175	10.5.18.184/30	10.5.18.185 – 10.5.18.186	10.5.18.187
176	10.5.18.188/30	10.5.18.189 – 10.5.18.190	10.5.18.191
177	10.5.18.192/30	10.5.18.193 – 10.5.18.194	10.5.18.195
178	10.5.18.196/30	10.5.18.197 – 10.5.18.198	10.5.18.199
179	10.5.18.200/30	10.5.18.201 – 10.5.18.202	10.5.18.203
180	10.5.18.204/30	10.5.18.205 – 10.5.18.206	10.5.18.207
181	10.5.18.208/30	10.5.18.209 – 10.5.18.210	10.5.18.211
182	10.5.18.212/30	10.5.18.213 – 10.5.18.214	10.5.18.215
183	10.5.18.216/30	10.5.18.217 – 10.5.18.218	10.5.18.219
184	10.5.18.220/30	10.5.18.221 – 10.5.18.222	10.5.18.223
185	10.5.18.224/30	10.5.18.225 – 10.5.18.226	10.5.18.227
186	10.5.18.228/30	10.5.18.229 – 10.5.18.230	10.5.18.231
187	10.5.18.232/30	10.5.18.233 – 10.5.18.234	10.5.18.235
188	10.5.18.236/30	10.5.18.237 – 10.5.18.238	10.5.18.239
189	10.5.18.240/30	10.5.18.241 – 10.5.18.242	10.5.18.243
190	10.5.18.244/30	10.5.18.245 – 10.5.18.246	10.5.18.247
191	10.5.18.248/30	10.5.18.249 – 10.5.18.250	10.5.18.251
192	10.5.18.252/30	10.5.18.253 – 10.5.18.254	10.5.18.255
193	10.5.19.0/30	10.5.19.1 – 10.5.19.2	10.5.19.3
194	10.5.19.4/30	10.5.19.5 – 10.5.19.6	10.5.19.7
195	10.5.19.8/30	10.5.19.9 – 10.5.19.10	10.5.19.11
196	10.5.19.12/30	10.5.19.13 – 10.5.19.14	10.5.19.15
197	10.5.19.16/30	10.5.19.17 – 10.5.19.18	10.5.19.19
198	10.5.19.20/30	10.5.19.21 – 10.5.19.22	10.5.19.23
199	10.5.19.24/30	10.5.19.25 – 10.5.19.26	10.5.19.27
200	10.5.19.28/30	10.5.19.29 – 10.5.19.30	10.5.19.31
201	10.5.19.32/30	10.5.19.33 – 10.5.19.34	10.5.19.35
202	10.5.19.36/30	10.5.19.37 – 10.5.19.38	10.5.19.39
203	10.5.19.40/30	10.5.19.41 – 10.5.19.42	10.5.19.43
204	10.5.19.44/30	10.5.19.45 – 10.5.19.46	10.5.19.47
205	10.5.19.48/30	10.5.19.49 – 10.5.19.50	10.5.19.51
206	10.5.19.52/30	10.5.19.53 – 10.5.19.54	10.5.19.55
207	10.5.19.56/30	10.5.19.57 – 10.5.19.58	10.5.19.59
208	10.5.19.60/30	10.5.19.61 – 10.5.19.62	10.5.19.63
209	10.5.19.64/30	10.5.19.65 – 10.5.19.66	10.5.19.67
210	10.5.19.68/30	10.5.19.69 – 10.5.19.70	10.5.19.71
211	10.5.19.72/30	10.5.19.73 – 10.5.19.74	10.5.19.75
212	10.5.19.76/30	10.5.19.77 – 10.5.19.78	10.5.19.79
213	10.5.19.80/30	10.5.19.81 – 10.5.19.82	10.5.19.83
214	10.5.19.84/30	10.5.19.85 – 10.5.19.86	10.5.19.87
215	10.5.19.88/30	10.5.19.89 – 10.5.19.90	10.5.19.91
216	10.5.19.92/30	10.5.19.93 – 10.5.19.94	10.5.19.95
217	10.5.19.96/30	10.5.19.97 – 10.5.19.98	10.5.19.99
218	10.5.19.100/30	10.5.19.101 – 10.5.19.102	10.5.19.103
219	10.5.19.104/30	10.5.19.105 – 10.5.19.106	10.5.19.107
220	10.5.19.108/30	10.5.19.109 – 10.5.19.110	10.5.19.111
221	10.5.19.112/30	10.5.19.113 – 10.5.19.114	10.5.19.115
222	10.5.19.116/30	10.5.19.117 – 10.5.19.118	10.5.19.119
223	10.5.19.120/30	10.5.19.121 – 10.5.19.122	10.5.19.123
224	10.5.19.124/30	10.5.19.125 – 10.5.19.126	10.5.19.127
225	10.5.19.128/30	10.5.19.129 – 10.5.19.130	10.5.19.131
226	10.5.19.132/30	10.5.19.133 – 10.5.19.134	10.5.19.135
227	10.5.19.136/30	10.5.19.137 – 10.5.19.138	10.5.19.139
228	10.5.19.140/30	10.5.19.141 – 10.5.19.142	10.5.19.143
229	10.5.19.144/30	10.5.19.145 – 10.5.19.146	10.5.19.147
230	10.5.19.148/30	10.5.19.149 – 10.5.19.150	10.5.19.151
231	10.5.19.152/30	10.5.19.153 – 10.5.19.154	10.5.19.155
232	10.5.19.156/30	10.5.19.157 – 10.5.19.158	10.5.19.159
233	10.5.19.160/30	10.5.19.161 – 10.5.19.162	10.5.19.163
234	10.5.19.164/30	10.5.19.165 – 10.5.19.166	10.5.19.167
235	10.5.19.168/30	10.5.19.169 – 10.5.19.170	10.5.19.171
236	10.5.19.172/30	10.5.19.173 – 10.5.19.174	10.5.19.175
237	10.5.19.176/30	10.5.19.177 – 10.5.19.178	10.5.19.179
238	10.5.19.180/30	10.5.19.181 – 10.5.19.182	10.5.19.183
239	10.5.19.184/30	10.5.19.185 – 10.5.19.186	10.5.19.187
240	10.5.19.188/30	10.5.19.189 – 10.5.19.190	10.5.19.191
241	10.5.19.192/30	10.5.19.193 – 10.5.19.194	10.5.19.195
242	10.5.19.196/30	10.5.19.197 – 10.5.19.198	10.5.19.199
243	10.5.19.200/30	10.5.19.201 – 10.5.19.202	10.5.19.203
244	10.5.19.204/30	10.5.19.205 – 10.5.19.206	10.5.19.207
245	10.5.19.208/30	10.5.19.209 – 10.5.19.210	10.5.19.211
246	10.5.19.212/30	10.5.19.213 – 10.5.19.214	10.5.19.215
247	10.5.19.216/30	10.5.19.217 – 10.5.19.218	10.5.19.219
248	10.5.19.220/30	10.5.19.221 – 10.5.19.222	10.5.19.223
249	10.5.19.224/30	10.5.19.225 – 10.5.19.226	10.5.19.227
250	10.5.19.228/30	10.5.19.229 – 10.5.19.230	10.5.19.231
251	10.5.19.232/30	10.5.19.233 – 10.5.19.234	10.5.19.235
252	10.5.19.236/30	10.5.19.237 – 10.5.19.238	10.5.19.239
253	10.5.19.240/30	10.5.19.241 – 10.5.19.242	10.5.19.243
254	10.5.19.244/30	10.5.19.245 – 10.5.19.246	10.5.19.247
255	10.5.19.248/30	10.5.19.249 – 10.5.19.250	10.5.19.251
256	10.5.19.252/30	10.5.19.253 – 10.5.19.254	10.5.19.255

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 →