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)10.0.208.0/21

network10.0.208.0/21

broadcast10.0.215.255

first host10.0.208.1

last host10.0.215.254

subnet mask255.255.248.0

wildcard0.0.7.255

addresses2,048

usable hosts2,046

classA

ipcalc 10.0.208.0/21

address00001010.00000000.11010000.00000000

subnet mask11111111.11111111.11111000.00000000

network00001010.00000000.11010000.00000000

broadcast00001010.00000000.11010111.11111111

green = network part, grey = host part

hex0x0a00d000

decimal167825408

reverse dns0.208.0.10.in-addr.arpa

ipv4-mapped::ffff:a00:d000

/21 split into /29 · 256 subnets

close ×

#	network	host range	broadcast
1	10.0.208.0/29	10.0.208.1 – 10.0.208.6	10.0.208.7
2	10.0.208.8/29	10.0.208.9 – 10.0.208.14	10.0.208.15
3	10.0.208.16/29	10.0.208.17 – 10.0.208.22	10.0.208.23
4	10.0.208.24/29	10.0.208.25 – 10.0.208.30	10.0.208.31
5	10.0.208.32/29	10.0.208.33 – 10.0.208.38	10.0.208.39
6	10.0.208.40/29	10.0.208.41 – 10.0.208.46	10.0.208.47
7	10.0.208.48/29	10.0.208.49 – 10.0.208.54	10.0.208.55
8	10.0.208.56/29	10.0.208.57 – 10.0.208.62	10.0.208.63
9	10.0.208.64/29	10.0.208.65 – 10.0.208.70	10.0.208.71
10	10.0.208.72/29	10.0.208.73 – 10.0.208.78	10.0.208.79
11	10.0.208.80/29	10.0.208.81 – 10.0.208.86	10.0.208.87
12	10.0.208.88/29	10.0.208.89 – 10.0.208.94	10.0.208.95
13	10.0.208.96/29	10.0.208.97 – 10.0.208.102	10.0.208.103
14	10.0.208.104/29	10.0.208.105 – 10.0.208.110	10.0.208.111
15	10.0.208.112/29	10.0.208.113 – 10.0.208.118	10.0.208.119
16	10.0.208.120/29	10.0.208.121 – 10.0.208.126	10.0.208.127
17	10.0.208.128/29	10.0.208.129 – 10.0.208.134	10.0.208.135
18	10.0.208.136/29	10.0.208.137 – 10.0.208.142	10.0.208.143
19	10.0.208.144/29	10.0.208.145 – 10.0.208.150	10.0.208.151
20	10.0.208.152/29	10.0.208.153 – 10.0.208.158	10.0.208.159
21	10.0.208.160/29	10.0.208.161 – 10.0.208.166	10.0.208.167
22	10.0.208.168/29	10.0.208.169 – 10.0.208.174	10.0.208.175
23	10.0.208.176/29	10.0.208.177 – 10.0.208.182	10.0.208.183
24	10.0.208.184/29	10.0.208.185 – 10.0.208.190	10.0.208.191
25	10.0.208.192/29	10.0.208.193 – 10.0.208.198	10.0.208.199
26	10.0.208.200/29	10.0.208.201 – 10.0.208.206	10.0.208.207
27	10.0.208.208/29	10.0.208.209 – 10.0.208.214	10.0.208.215
28	10.0.208.216/29	10.0.208.217 – 10.0.208.222	10.0.208.223
29	10.0.208.224/29	10.0.208.225 – 10.0.208.230	10.0.208.231
30	10.0.208.232/29	10.0.208.233 – 10.0.208.238	10.0.208.239
31	10.0.208.240/29	10.0.208.241 – 10.0.208.246	10.0.208.247
32	10.0.208.248/29	10.0.208.249 – 10.0.208.254	10.0.208.255
33	10.0.209.0/29	10.0.209.1 – 10.0.209.6	10.0.209.7
34	10.0.209.8/29	10.0.209.9 – 10.0.209.14	10.0.209.15
35	10.0.209.16/29	10.0.209.17 – 10.0.209.22	10.0.209.23
36	10.0.209.24/29	10.0.209.25 – 10.0.209.30	10.0.209.31
37	10.0.209.32/29	10.0.209.33 – 10.0.209.38	10.0.209.39
38	10.0.209.40/29	10.0.209.41 – 10.0.209.46	10.0.209.47
39	10.0.209.48/29	10.0.209.49 – 10.0.209.54	10.0.209.55
40	10.0.209.56/29	10.0.209.57 – 10.0.209.62	10.0.209.63
41	10.0.209.64/29	10.0.209.65 – 10.0.209.70	10.0.209.71
42	10.0.209.72/29	10.0.209.73 – 10.0.209.78	10.0.209.79
43	10.0.209.80/29	10.0.209.81 – 10.0.209.86	10.0.209.87
44	10.0.209.88/29	10.0.209.89 – 10.0.209.94	10.0.209.95
45	10.0.209.96/29	10.0.209.97 – 10.0.209.102	10.0.209.103
46	10.0.209.104/29	10.0.209.105 – 10.0.209.110	10.0.209.111
47	10.0.209.112/29	10.0.209.113 – 10.0.209.118	10.0.209.119
48	10.0.209.120/29	10.0.209.121 – 10.0.209.126	10.0.209.127
49	10.0.209.128/29	10.0.209.129 – 10.0.209.134	10.0.209.135
50	10.0.209.136/29	10.0.209.137 – 10.0.209.142	10.0.209.143
51	10.0.209.144/29	10.0.209.145 – 10.0.209.150	10.0.209.151
52	10.0.209.152/29	10.0.209.153 – 10.0.209.158	10.0.209.159
53	10.0.209.160/29	10.0.209.161 – 10.0.209.166	10.0.209.167
54	10.0.209.168/29	10.0.209.169 – 10.0.209.174	10.0.209.175
55	10.0.209.176/29	10.0.209.177 – 10.0.209.182	10.0.209.183
56	10.0.209.184/29	10.0.209.185 – 10.0.209.190	10.0.209.191
57	10.0.209.192/29	10.0.209.193 – 10.0.209.198	10.0.209.199
58	10.0.209.200/29	10.0.209.201 – 10.0.209.206	10.0.209.207
59	10.0.209.208/29	10.0.209.209 – 10.0.209.214	10.0.209.215
60	10.0.209.216/29	10.0.209.217 – 10.0.209.222	10.0.209.223
61	10.0.209.224/29	10.0.209.225 – 10.0.209.230	10.0.209.231
62	10.0.209.232/29	10.0.209.233 – 10.0.209.238	10.0.209.239
63	10.0.209.240/29	10.0.209.241 – 10.0.209.246	10.0.209.247
64	10.0.209.248/29	10.0.209.249 – 10.0.209.254	10.0.209.255
65	10.0.210.0/29	10.0.210.1 – 10.0.210.6	10.0.210.7
66	10.0.210.8/29	10.0.210.9 – 10.0.210.14	10.0.210.15
67	10.0.210.16/29	10.0.210.17 – 10.0.210.22	10.0.210.23
68	10.0.210.24/29	10.0.210.25 – 10.0.210.30	10.0.210.31
69	10.0.210.32/29	10.0.210.33 – 10.0.210.38	10.0.210.39
70	10.0.210.40/29	10.0.210.41 – 10.0.210.46	10.0.210.47
71	10.0.210.48/29	10.0.210.49 – 10.0.210.54	10.0.210.55
72	10.0.210.56/29	10.0.210.57 – 10.0.210.62	10.0.210.63
73	10.0.210.64/29	10.0.210.65 – 10.0.210.70	10.0.210.71
74	10.0.210.72/29	10.0.210.73 – 10.0.210.78	10.0.210.79
75	10.0.210.80/29	10.0.210.81 – 10.0.210.86	10.0.210.87
76	10.0.210.88/29	10.0.210.89 – 10.0.210.94	10.0.210.95
77	10.0.210.96/29	10.0.210.97 – 10.0.210.102	10.0.210.103
78	10.0.210.104/29	10.0.210.105 – 10.0.210.110	10.0.210.111
79	10.0.210.112/29	10.0.210.113 – 10.0.210.118	10.0.210.119
80	10.0.210.120/29	10.0.210.121 – 10.0.210.126	10.0.210.127
81	10.0.210.128/29	10.0.210.129 – 10.0.210.134	10.0.210.135
82	10.0.210.136/29	10.0.210.137 – 10.0.210.142	10.0.210.143
83	10.0.210.144/29	10.0.210.145 – 10.0.210.150	10.0.210.151
84	10.0.210.152/29	10.0.210.153 – 10.0.210.158	10.0.210.159
85	10.0.210.160/29	10.0.210.161 – 10.0.210.166	10.0.210.167
86	10.0.210.168/29	10.0.210.169 – 10.0.210.174	10.0.210.175
87	10.0.210.176/29	10.0.210.177 – 10.0.210.182	10.0.210.183
88	10.0.210.184/29	10.0.210.185 – 10.0.210.190	10.0.210.191
89	10.0.210.192/29	10.0.210.193 – 10.0.210.198	10.0.210.199
90	10.0.210.200/29	10.0.210.201 – 10.0.210.206	10.0.210.207
91	10.0.210.208/29	10.0.210.209 – 10.0.210.214	10.0.210.215
92	10.0.210.216/29	10.0.210.217 – 10.0.210.222	10.0.210.223
93	10.0.210.224/29	10.0.210.225 – 10.0.210.230	10.0.210.231
94	10.0.210.232/29	10.0.210.233 – 10.0.210.238	10.0.210.239
95	10.0.210.240/29	10.0.210.241 – 10.0.210.246	10.0.210.247
96	10.0.210.248/29	10.0.210.249 – 10.0.210.254	10.0.210.255
97	10.0.211.0/29	10.0.211.1 – 10.0.211.6	10.0.211.7
98	10.0.211.8/29	10.0.211.9 – 10.0.211.14	10.0.211.15
99	10.0.211.16/29	10.0.211.17 – 10.0.211.22	10.0.211.23
100	10.0.211.24/29	10.0.211.25 – 10.0.211.30	10.0.211.31
101	10.0.211.32/29	10.0.211.33 – 10.0.211.38	10.0.211.39
102	10.0.211.40/29	10.0.211.41 – 10.0.211.46	10.0.211.47
103	10.0.211.48/29	10.0.211.49 – 10.0.211.54	10.0.211.55
104	10.0.211.56/29	10.0.211.57 – 10.0.211.62	10.0.211.63
105	10.0.211.64/29	10.0.211.65 – 10.0.211.70	10.0.211.71
106	10.0.211.72/29	10.0.211.73 – 10.0.211.78	10.0.211.79
107	10.0.211.80/29	10.0.211.81 – 10.0.211.86	10.0.211.87
108	10.0.211.88/29	10.0.211.89 – 10.0.211.94	10.0.211.95
109	10.0.211.96/29	10.0.211.97 – 10.0.211.102	10.0.211.103
110	10.0.211.104/29	10.0.211.105 – 10.0.211.110	10.0.211.111
111	10.0.211.112/29	10.0.211.113 – 10.0.211.118	10.0.211.119
112	10.0.211.120/29	10.0.211.121 – 10.0.211.126	10.0.211.127
113	10.0.211.128/29	10.0.211.129 – 10.0.211.134	10.0.211.135
114	10.0.211.136/29	10.0.211.137 – 10.0.211.142	10.0.211.143
115	10.0.211.144/29	10.0.211.145 – 10.0.211.150	10.0.211.151
116	10.0.211.152/29	10.0.211.153 – 10.0.211.158	10.0.211.159
117	10.0.211.160/29	10.0.211.161 – 10.0.211.166	10.0.211.167
118	10.0.211.168/29	10.0.211.169 – 10.0.211.174	10.0.211.175
119	10.0.211.176/29	10.0.211.177 – 10.0.211.182	10.0.211.183
120	10.0.211.184/29	10.0.211.185 – 10.0.211.190	10.0.211.191
121	10.0.211.192/29	10.0.211.193 – 10.0.211.198	10.0.211.199
122	10.0.211.200/29	10.0.211.201 – 10.0.211.206	10.0.211.207
123	10.0.211.208/29	10.0.211.209 – 10.0.211.214	10.0.211.215
124	10.0.211.216/29	10.0.211.217 – 10.0.211.222	10.0.211.223
125	10.0.211.224/29	10.0.211.225 – 10.0.211.230	10.0.211.231
126	10.0.211.232/29	10.0.211.233 – 10.0.211.238	10.0.211.239
127	10.0.211.240/29	10.0.211.241 – 10.0.211.246	10.0.211.247
128	10.0.211.248/29	10.0.211.249 – 10.0.211.254	10.0.211.255
129	10.0.212.0/29	10.0.212.1 – 10.0.212.6	10.0.212.7
130	10.0.212.8/29	10.0.212.9 – 10.0.212.14	10.0.212.15
131	10.0.212.16/29	10.0.212.17 – 10.0.212.22	10.0.212.23
132	10.0.212.24/29	10.0.212.25 – 10.0.212.30	10.0.212.31
133	10.0.212.32/29	10.0.212.33 – 10.0.212.38	10.0.212.39
134	10.0.212.40/29	10.0.212.41 – 10.0.212.46	10.0.212.47
135	10.0.212.48/29	10.0.212.49 – 10.0.212.54	10.0.212.55
136	10.0.212.56/29	10.0.212.57 – 10.0.212.62	10.0.212.63
137	10.0.212.64/29	10.0.212.65 – 10.0.212.70	10.0.212.71
138	10.0.212.72/29	10.0.212.73 – 10.0.212.78	10.0.212.79
139	10.0.212.80/29	10.0.212.81 – 10.0.212.86	10.0.212.87
140	10.0.212.88/29	10.0.212.89 – 10.0.212.94	10.0.212.95
141	10.0.212.96/29	10.0.212.97 – 10.0.212.102	10.0.212.103
142	10.0.212.104/29	10.0.212.105 – 10.0.212.110	10.0.212.111
143	10.0.212.112/29	10.0.212.113 – 10.0.212.118	10.0.212.119
144	10.0.212.120/29	10.0.212.121 – 10.0.212.126	10.0.212.127
145	10.0.212.128/29	10.0.212.129 – 10.0.212.134	10.0.212.135
146	10.0.212.136/29	10.0.212.137 – 10.0.212.142	10.0.212.143
147	10.0.212.144/29	10.0.212.145 – 10.0.212.150	10.0.212.151
148	10.0.212.152/29	10.0.212.153 – 10.0.212.158	10.0.212.159
149	10.0.212.160/29	10.0.212.161 – 10.0.212.166	10.0.212.167
150	10.0.212.168/29	10.0.212.169 – 10.0.212.174	10.0.212.175
151	10.0.212.176/29	10.0.212.177 – 10.0.212.182	10.0.212.183
152	10.0.212.184/29	10.0.212.185 – 10.0.212.190	10.0.212.191
153	10.0.212.192/29	10.0.212.193 – 10.0.212.198	10.0.212.199
154	10.0.212.200/29	10.0.212.201 – 10.0.212.206	10.0.212.207
155	10.0.212.208/29	10.0.212.209 – 10.0.212.214	10.0.212.215
156	10.0.212.216/29	10.0.212.217 – 10.0.212.222	10.0.212.223
157	10.0.212.224/29	10.0.212.225 – 10.0.212.230	10.0.212.231
158	10.0.212.232/29	10.0.212.233 – 10.0.212.238	10.0.212.239
159	10.0.212.240/29	10.0.212.241 – 10.0.212.246	10.0.212.247
160	10.0.212.248/29	10.0.212.249 – 10.0.212.254	10.0.212.255
161	10.0.213.0/29	10.0.213.1 – 10.0.213.6	10.0.213.7
162	10.0.213.8/29	10.0.213.9 – 10.0.213.14	10.0.213.15
163	10.0.213.16/29	10.0.213.17 – 10.0.213.22	10.0.213.23
164	10.0.213.24/29	10.0.213.25 – 10.0.213.30	10.0.213.31
165	10.0.213.32/29	10.0.213.33 – 10.0.213.38	10.0.213.39
166	10.0.213.40/29	10.0.213.41 – 10.0.213.46	10.0.213.47
167	10.0.213.48/29	10.0.213.49 – 10.0.213.54	10.0.213.55
168	10.0.213.56/29	10.0.213.57 – 10.0.213.62	10.0.213.63
169	10.0.213.64/29	10.0.213.65 – 10.0.213.70	10.0.213.71
170	10.0.213.72/29	10.0.213.73 – 10.0.213.78	10.0.213.79
171	10.0.213.80/29	10.0.213.81 – 10.0.213.86	10.0.213.87
172	10.0.213.88/29	10.0.213.89 – 10.0.213.94	10.0.213.95
173	10.0.213.96/29	10.0.213.97 – 10.0.213.102	10.0.213.103
174	10.0.213.104/29	10.0.213.105 – 10.0.213.110	10.0.213.111
175	10.0.213.112/29	10.0.213.113 – 10.0.213.118	10.0.213.119
176	10.0.213.120/29	10.0.213.121 – 10.0.213.126	10.0.213.127
177	10.0.213.128/29	10.0.213.129 – 10.0.213.134	10.0.213.135
178	10.0.213.136/29	10.0.213.137 – 10.0.213.142	10.0.213.143
179	10.0.213.144/29	10.0.213.145 – 10.0.213.150	10.0.213.151
180	10.0.213.152/29	10.0.213.153 – 10.0.213.158	10.0.213.159
181	10.0.213.160/29	10.0.213.161 – 10.0.213.166	10.0.213.167
182	10.0.213.168/29	10.0.213.169 – 10.0.213.174	10.0.213.175
183	10.0.213.176/29	10.0.213.177 – 10.0.213.182	10.0.213.183
184	10.0.213.184/29	10.0.213.185 – 10.0.213.190	10.0.213.191
185	10.0.213.192/29	10.0.213.193 – 10.0.213.198	10.0.213.199
186	10.0.213.200/29	10.0.213.201 – 10.0.213.206	10.0.213.207
187	10.0.213.208/29	10.0.213.209 – 10.0.213.214	10.0.213.215
188	10.0.213.216/29	10.0.213.217 – 10.0.213.222	10.0.213.223
189	10.0.213.224/29	10.0.213.225 – 10.0.213.230	10.0.213.231
190	10.0.213.232/29	10.0.213.233 – 10.0.213.238	10.0.213.239
191	10.0.213.240/29	10.0.213.241 – 10.0.213.246	10.0.213.247
192	10.0.213.248/29	10.0.213.249 – 10.0.213.254	10.0.213.255
193	10.0.214.0/29	10.0.214.1 – 10.0.214.6	10.0.214.7
194	10.0.214.8/29	10.0.214.9 – 10.0.214.14	10.0.214.15
195	10.0.214.16/29	10.0.214.17 – 10.0.214.22	10.0.214.23
196	10.0.214.24/29	10.0.214.25 – 10.0.214.30	10.0.214.31
197	10.0.214.32/29	10.0.214.33 – 10.0.214.38	10.0.214.39
198	10.0.214.40/29	10.0.214.41 – 10.0.214.46	10.0.214.47
199	10.0.214.48/29	10.0.214.49 – 10.0.214.54	10.0.214.55
200	10.0.214.56/29	10.0.214.57 – 10.0.214.62	10.0.214.63
201	10.0.214.64/29	10.0.214.65 – 10.0.214.70	10.0.214.71
202	10.0.214.72/29	10.0.214.73 – 10.0.214.78	10.0.214.79
203	10.0.214.80/29	10.0.214.81 – 10.0.214.86	10.0.214.87
204	10.0.214.88/29	10.0.214.89 – 10.0.214.94	10.0.214.95
205	10.0.214.96/29	10.0.214.97 – 10.0.214.102	10.0.214.103
206	10.0.214.104/29	10.0.214.105 – 10.0.214.110	10.0.214.111
207	10.0.214.112/29	10.0.214.113 – 10.0.214.118	10.0.214.119
208	10.0.214.120/29	10.0.214.121 – 10.0.214.126	10.0.214.127
209	10.0.214.128/29	10.0.214.129 – 10.0.214.134	10.0.214.135
210	10.0.214.136/29	10.0.214.137 – 10.0.214.142	10.0.214.143
211	10.0.214.144/29	10.0.214.145 – 10.0.214.150	10.0.214.151
212	10.0.214.152/29	10.0.214.153 – 10.0.214.158	10.0.214.159
213	10.0.214.160/29	10.0.214.161 – 10.0.214.166	10.0.214.167
214	10.0.214.168/29	10.0.214.169 – 10.0.214.174	10.0.214.175
215	10.0.214.176/29	10.0.214.177 – 10.0.214.182	10.0.214.183
216	10.0.214.184/29	10.0.214.185 – 10.0.214.190	10.0.214.191
217	10.0.214.192/29	10.0.214.193 – 10.0.214.198	10.0.214.199
218	10.0.214.200/29	10.0.214.201 – 10.0.214.206	10.0.214.207
219	10.0.214.208/29	10.0.214.209 – 10.0.214.214	10.0.214.215
220	10.0.214.216/29	10.0.214.217 – 10.0.214.222	10.0.214.223
221	10.0.214.224/29	10.0.214.225 – 10.0.214.230	10.0.214.231
222	10.0.214.232/29	10.0.214.233 – 10.0.214.238	10.0.214.239
223	10.0.214.240/29	10.0.214.241 – 10.0.214.246	10.0.214.247
224	10.0.214.248/29	10.0.214.249 – 10.0.214.254	10.0.214.255
225	10.0.215.0/29	10.0.215.1 – 10.0.215.6	10.0.215.7
226	10.0.215.8/29	10.0.215.9 – 10.0.215.14	10.0.215.15
227	10.0.215.16/29	10.0.215.17 – 10.0.215.22	10.0.215.23
228	10.0.215.24/29	10.0.215.25 – 10.0.215.30	10.0.215.31
229	10.0.215.32/29	10.0.215.33 – 10.0.215.38	10.0.215.39
230	10.0.215.40/29	10.0.215.41 – 10.0.215.46	10.0.215.47
231	10.0.215.48/29	10.0.215.49 – 10.0.215.54	10.0.215.55
232	10.0.215.56/29	10.0.215.57 – 10.0.215.62	10.0.215.63
233	10.0.215.64/29	10.0.215.65 – 10.0.215.70	10.0.215.71
234	10.0.215.72/29	10.0.215.73 – 10.0.215.78	10.0.215.79
235	10.0.215.80/29	10.0.215.81 – 10.0.215.86	10.0.215.87
236	10.0.215.88/29	10.0.215.89 – 10.0.215.94	10.0.215.95
237	10.0.215.96/29	10.0.215.97 – 10.0.215.102	10.0.215.103
238	10.0.215.104/29	10.0.215.105 – 10.0.215.110	10.0.215.111
239	10.0.215.112/29	10.0.215.113 – 10.0.215.118	10.0.215.119
240	10.0.215.120/29	10.0.215.121 – 10.0.215.126	10.0.215.127
241	10.0.215.128/29	10.0.215.129 – 10.0.215.134	10.0.215.135
242	10.0.215.136/29	10.0.215.137 – 10.0.215.142	10.0.215.143
243	10.0.215.144/29	10.0.215.145 – 10.0.215.150	10.0.215.151
244	10.0.215.152/29	10.0.215.153 – 10.0.215.158	10.0.215.159
245	10.0.215.160/29	10.0.215.161 – 10.0.215.166	10.0.215.167
246	10.0.215.168/29	10.0.215.169 – 10.0.215.174	10.0.215.175
247	10.0.215.176/29	10.0.215.177 – 10.0.215.182	10.0.215.183
248	10.0.215.184/29	10.0.215.185 – 10.0.215.190	10.0.215.191
249	10.0.215.192/29	10.0.215.193 – 10.0.215.198	10.0.215.199
250	10.0.215.200/29	10.0.215.201 – 10.0.215.206	10.0.215.207
251	10.0.215.208/29	10.0.215.209 – 10.0.215.214	10.0.215.215
252	10.0.215.216/29	10.0.215.217 – 10.0.215.222	10.0.215.223
253	10.0.215.224/29	10.0.215.225 – 10.0.215.230	10.0.215.231
254	10.0.215.232/29	10.0.215.233 – 10.0.215.238	10.0.215.239
255	10.0.215.240/29	10.0.215.241 – 10.0.215.246	10.0.215.247
256	10.0.215.248/29	10.0.215.249 – 10.0.215.254	10.0.215.255

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 /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 →