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)10.2.16.0/21

network10.2.16.0/21

broadcast10.2.23.255

first host10.2.16.1

last host10.2.23.254

subnet mask255.255.248.0

wildcard0.0.7.255

addresses2,048

usable hosts2,046

classA

ipcalc 10.2.16.0/21

address00001010.00000010.00010000.00000000

subnet mask11111111.11111111.11111000.00000000

network00001010.00000010.00010000.00000000

broadcast00001010.00000010.00010111.11111111

green = network part, grey = host part

hex0x0a021000

decimal167907328

reverse dns0.16.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:1000

/21 split into /29 · 256 subnets

close ×

#	network	host range	broadcast
1	10.2.16.0/29	10.2.16.1 – 10.2.16.6	10.2.16.7
2	10.2.16.8/29	10.2.16.9 – 10.2.16.14	10.2.16.15
3	10.2.16.16/29	10.2.16.17 – 10.2.16.22	10.2.16.23
4	10.2.16.24/29	10.2.16.25 – 10.2.16.30	10.2.16.31
5	10.2.16.32/29	10.2.16.33 – 10.2.16.38	10.2.16.39
6	10.2.16.40/29	10.2.16.41 – 10.2.16.46	10.2.16.47
7	10.2.16.48/29	10.2.16.49 – 10.2.16.54	10.2.16.55
8	10.2.16.56/29	10.2.16.57 – 10.2.16.62	10.2.16.63
9	10.2.16.64/29	10.2.16.65 – 10.2.16.70	10.2.16.71
10	10.2.16.72/29	10.2.16.73 – 10.2.16.78	10.2.16.79
11	10.2.16.80/29	10.2.16.81 – 10.2.16.86	10.2.16.87
12	10.2.16.88/29	10.2.16.89 – 10.2.16.94	10.2.16.95
13	10.2.16.96/29	10.2.16.97 – 10.2.16.102	10.2.16.103
14	10.2.16.104/29	10.2.16.105 – 10.2.16.110	10.2.16.111
15	10.2.16.112/29	10.2.16.113 – 10.2.16.118	10.2.16.119
16	10.2.16.120/29	10.2.16.121 – 10.2.16.126	10.2.16.127
17	10.2.16.128/29	10.2.16.129 – 10.2.16.134	10.2.16.135
18	10.2.16.136/29	10.2.16.137 – 10.2.16.142	10.2.16.143
19	10.2.16.144/29	10.2.16.145 – 10.2.16.150	10.2.16.151
20	10.2.16.152/29	10.2.16.153 – 10.2.16.158	10.2.16.159
21	10.2.16.160/29	10.2.16.161 – 10.2.16.166	10.2.16.167
22	10.2.16.168/29	10.2.16.169 – 10.2.16.174	10.2.16.175
23	10.2.16.176/29	10.2.16.177 – 10.2.16.182	10.2.16.183
24	10.2.16.184/29	10.2.16.185 – 10.2.16.190	10.2.16.191
25	10.2.16.192/29	10.2.16.193 – 10.2.16.198	10.2.16.199
26	10.2.16.200/29	10.2.16.201 – 10.2.16.206	10.2.16.207
27	10.2.16.208/29	10.2.16.209 – 10.2.16.214	10.2.16.215
28	10.2.16.216/29	10.2.16.217 – 10.2.16.222	10.2.16.223
29	10.2.16.224/29	10.2.16.225 – 10.2.16.230	10.2.16.231
30	10.2.16.232/29	10.2.16.233 – 10.2.16.238	10.2.16.239
31	10.2.16.240/29	10.2.16.241 – 10.2.16.246	10.2.16.247
32	10.2.16.248/29	10.2.16.249 – 10.2.16.254	10.2.16.255
33	10.2.17.0/29	10.2.17.1 – 10.2.17.6	10.2.17.7
34	10.2.17.8/29	10.2.17.9 – 10.2.17.14	10.2.17.15
35	10.2.17.16/29	10.2.17.17 – 10.2.17.22	10.2.17.23
36	10.2.17.24/29	10.2.17.25 – 10.2.17.30	10.2.17.31
37	10.2.17.32/29	10.2.17.33 – 10.2.17.38	10.2.17.39
38	10.2.17.40/29	10.2.17.41 – 10.2.17.46	10.2.17.47
39	10.2.17.48/29	10.2.17.49 – 10.2.17.54	10.2.17.55
40	10.2.17.56/29	10.2.17.57 – 10.2.17.62	10.2.17.63
41	10.2.17.64/29	10.2.17.65 – 10.2.17.70	10.2.17.71
42	10.2.17.72/29	10.2.17.73 – 10.2.17.78	10.2.17.79
43	10.2.17.80/29	10.2.17.81 – 10.2.17.86	10.2.17.87
44	10.2.17.88/29	10.2.17.89 – 10.2.17.94	10.2.17.95
45	10.2.17.96/29	10.2.17.97 – 10.2.17.102	10.2.17.103
46	10.2.17.104/29	10.2.17.105 – 10.2.17.110	10.2.17.111
47	10.2.17.112/29	10.2.17.113 – 10.2.17.118	10.2.17.119
48	10.2.17.120/29	10.2.17.121 – 10.2.17.126	10.2.17.127
49	10.2.17.128/29	10.2.17.129 – 10.2.17.134	10.2.17.135
50	10.2.17.136/29	10.2.17.137 – 10.2.17.142	10.2.17.143
51	10.2.17.144/29	10.2.17.145 – 10.2.17.150	10.2.17.151
52	10.2.17.152/29	10.2.17.153 – 10.2.17.158	10.2.17.159
53	10.2.17.160/29	10.2.17.161 – 10.2.17.166	10.2.17.167
54	10.2.17.168/29	10.2.17.169 – 10.2.17.174	10.2.17.175
55	10.2.17.176/29	10.2.17.177 – 10.2.17.182	10.2.17.183
56	10.2.17.184/29	10.2.17.185 – 10.2.17.190	10.2.17.191
57	10.2.17.192/29	10.2.17.193 – 10.2.17.198	10.2.17.199
58	10.2.17.200/29	10.2.17.201 – 10.2.17.206	10.2.17.207
59	10.2.17.208/29	10.2.17.209 – 10.2.17.214	10.2.17.215
60	10.2.17.216/29	10.2.17.217 – 10.2.17.222	10.2.17.223
61	10.2.17.224/29	10.2.17.225 – 10.2.17.230	10.2.17.231
62	10.2.17.232/29	10.2.17.233 – 10.2.17.238	10.2.17.239
63	10.2.17.240/29	10.2.17.241 – 10.2.17.246	10.2.17.247
64	10.2.17.248/29	10.2.17.249 – 10.2.17.254	10.2.17.255
65	10.2.18.0/29	10.2.18.1 – 10.2.18.6	10.2.18.7
66	10.2.18.8/29	10.2.18.9 – 10.2.18.14	10.2.18.15
67	10.2.18.16/29	10.2.18.17 – 10.2.18.22	10.2.18.23
68	10.2.18.24/29	10.2.18.25 – 10.2.18.30	10.2.18.31
69	10.2.18.32/29	10.2.18.33 – 10.2.18.38	10.2.18.39
70	10.2.18.40/29	10.2.18.41 – 10.2.18.46	10.2.18.47
71	10.2.18.48/29	10.2.18.49 – 10.2.18.54	10.2.18.55
72	10.2.18.56/29	10.2.18.57 – 10.2.18.62	10.2.18.63
73	10.2.18.64/29	10.2.18.65 – 10.2.18.70	10.2.18.71
74	10.2.18.72/29	10.2.18.73 – 10.2.18.78	10.2.18.79
75	10.2.18.80/29	10.2.18.81 – 10.2.18.86	10.2.18.87
76	10.2.18.88/29	10.2.18.89 – 10.2.18.94	10.2.18.95
77	10.2.18.96/29	10.2.18.97 – 10.2.18.102	10.2.18.103
78	10.2.18.104/29	10.2.18.105 – 10.2.18.110	10.2.18.111
79	10.2.18.112/29	10.2.18.113 – 10.2.18.118	10.2.18.119
80	10.2.18.120/29	10.2.18.121 – 10.2.18.126	10.2.18.127
81	10.2.18.128/29	10.2.18.129 – 10.2.18.134	10.2.18.135
82	10.2.18.136/29	10.2.18.137 – 10.2.18.142	10.2.18.143
83	10.2.18.144/29	10.2.18.145 – 10.2.18.150	10.2.18.151
84	10.2.18.152/29	10.2.18.153 – 10.2.18.158	10.2.18.159
85	10.2.18.160/29	10.2.18.161 – 10.2.18.166	10.2.18.167
86	10.2.18.168/29	10.2.18.169 – 10.2.18.174	10.2.18.175
87	10.2.18.176/29	10.2.18.177 – 10.2.18.182	10.2.18.183
88	10.2.18.184/29	10.2.18.185 – 10.2.18.190	10.2.18.191
89	10.2.18.192/29	10.2.18.193 – 10.2.18.198	10.2.18.199
90	10.2.18.200/29	10.2.18.201 – 10.2.18.206	10.2.18.207
91	10.2.18.208/29	10.2.18.209 – 10.2.18.214	10.2.18.215
92	10.2.18.216/29	10.2.18.217 – 10.2.18.222	10.2.18.223
93	10.2.18.224/29	10.2.18.225 – 10.2.18.230	10.2.18.231
94	10.2.18.232/29	10.2.18.233 – 10.2.18.238	10.2.18.239
95	10.2.18.240/29	10.2.18.241 – 10.2.18.246	10.2.18.247
96	10.2.18.248/29	10.2.18.249 – 10.2.18.254	10.2.18.255
97	10.2.19.0/29	10.2.19.1 – 10.2.19.6	10.2.19.7
98	10.2.19.8/29	10.2.19.9 – 10.2.19.14	10.2.19.15
99	10.2.19.16/29	10.2.19.17 – 10.2.19.22	10.2.19.23
100	10.2.19.24/29	10.2.19.25 – 10.2.19.30	10.2.19.31
101	10.2.19.32/29	10.2.19.33 – 10.2.19.38	10.2.19.39
102	10.2.19.40/29	10.2.19.41 – 10.2.19.46	10.2.19.47
103	10.2.19.48/29	10.2.19.49 – 10.2.19.54	10.2.19.55
104	10.2.19.56/29	10.2.19.57 – 10.2.19.62	10.2.19.63
105	10.2.19.64/29	10.2.19.65 – 10.2.19.70	10.2.19.71
106	10.2.19.72/29	10.2.19.73 – 10.2.19.78	10.2.19.79
107	10.2.19.80/29	10.2.19.81 – 10.2.19.86	10.2.19.87
108	10.2.19.88/29	10.2.19.89 – 10.2.19.94	10.2.19.95
109	10.2.19.96/29	10.2.19.97 – 10.2.19.102	10.2.19.103
110	10.2.19.104/29	10.2.19.105 – 10.2.19.110	10.2.19.111
111	10.2.19.112/29	10.2.19.113 – 10.2.19.118	10.2.19.119
112	10.2.19.120/29	10.2.19.121 – 10.2.19.126	10.2.19.127
113	10.2.19.128/29	10.2.19.129 – 10.2.19.134	10.2.19.135
114	10.2.19.136/29	10.2.19.137 – 10.2.19.142	10.2.19.143
115	10.2.19.144/29	10.2.19.145 – 10.2.19.150	10.2.19.151
116	10.2.19.152/29	10.2.19.153 – 10.2.19.158	10.2.19.159
117	10.2.19.160/29	10.2.19.161 – 10.2.19.166	10.2.19.167
118	10.2.19.168/29	10.2.19.169 – 10.2.19.174	10.2.19.175
119	10.2.19.176/29	10.2.19.177 – 10.2.19.182	10.2.19.183
120	10.2.19.184/29	10.2.19.185 – 10.2.19.190	10.2.19.191
121	10.2.19.192/29	10.2.19.193 – 10.2.19.198	10.2.19.199
122	10.2.19.200/29	10.2.19.201 – 10.2.19.206	10.2.19.207
123	10.2.19.208/29	10.2.19.209 – 10.2.19.214	10.2.19.215
124	10.2.19.216/29	10.2.19.217 – 10.2.19.222	10.2.19.223
125	10.2.19.224/29	10.2.19.225 – 10.2.19.230	10.2.19.231
126	10.2.19.232/29	10.2.19.233 – 10.2.19.238	10.2.19.239
127	10.2.19.240/29	10.2.19.241 – 10.2.19.246	10.2.19.247
128	10.2.19.248/29	10.2.19.249 – 10.2.19.254	10.2.19.255
129	10.2.20.0/29	10.2.20.1 – 10.2.20.6	10.2.20.7
130	10.2.20.8/29	10.2.20.9 – 10.2.20.14	10.2.20.15
131	10.2.20.16/29	10.2.20.17 – 10.2.20.22	10.2.20.23
132	10.2.20.24/29	10.2.20.25 – 10.2.20.30	10.2.20.31
133	10.2.20.32/29	10.2.20.33 – 10.2.20.38	10.2.20.39
134	10.2.20.40/29	10.2.20.41 – 10.2.20.46	10.2.20.47
135	10.2.20.48/29	10.2.20.49 – 10.2.20.54	10.2.20.55
136	10.2.20.56/29	10.2.20.57 – 10.2.20.62	10.2.20.63
137	10.2.20.64/29	10.2.20.65 – 10.2.20.70	10.2.20.71
138	10.2.20.72/29	10.2.20.73 – 10.2.20.78	10.2.20.79
139	10.2.20.80/29	10.2.20.81 – 10.2.20.86	10.2.20.87
140	10.2.20.88/29	10.2.20.89 – 10.2.20.94	10.2.20.95
141	10.2.20.96/29	10.2.20.97 – 10.2.20.102	10.2.20.103
142	10.2.20.104/29	10.2.20.105 – 10.2.20.110	10.2.20.111
143	10.2.20.112/29	10.2.20.113 – 10.2.20.118	10.2.20.119
144	10.2.20.120/29	10.2.20.121 – 10.2.20.126	10.2.20.127
145	10.2.20.128/29	10.2.20.129 – 10.2.20.134	10.2.20.135
146	10.2.20.136/29	10.2.20.137 – 10.2.20.142	10.2.20.143
147	10.2.20.144/29	10.2.20.145 – 10.2.20.150	10.2.20.151
148	10.2.20.152/29	10.2.20.153 – 10.2.20.158	10.2.20.159
149	10.2.20.160/29	10.2.20.161 – 10.2.20.166	10.2.20.167
150	10.2.20.168/29	10.2.20.169 – 10.2.20.174	10.2.20.175
151	10.2.20.176/29	10.2.20.177 – 10.2.20.182	10.2.20.183
152	10.2.20.184/29	10.2.20.185 – 10.2.20.190	10.2.20.191
153	10.2.20.192/29	10.2.20.193 – 10.2.20.198	10.2.20.199
154	10.2.20.200/29	10.2.20.201 – 10.2.20.206	10.2.20.207
155	10.2.20.208/29	10.2.20.209 – 10.2.20.214	10.2.20.215
156	10.2.20.216/29	10.2.20.217 – 10.2.20.222	10.2.20.223
157	10.2.20.224/29	10.2.20.225 – 10.2.20.230	10.2.20.231
158	10.2.20.232/29	10.2.20.233 – 10.2.20.238	10.2.20.239
159	10.2.20.240/29	10.2.20.241 – 10.2.20.246	10.2.20.247
160	10.2.20.248/29	10.2.20.249 – 10.2.20.254	10.2.20.255
161	10.2.21.0/29	10.2.21.1 – 10.2.21.6	10.2.21.7
162	10.2.21.8/29	10.2.21.9 – 10.2.21.14	10.2.21.15
163	10.2.21.16/29	10.2.21.17 – 10.2.21.22	10.2.21.23
164	10.2.21.24/29	10.2.21.25 – 10.2.21.30	10.2.21.31
165	10.2.21.32/29	10.2.21.33 – 10.2.21.38	10.2.21.39
166	10.2.21.40/29	10.2.21.41 – 10.2.21.46	10.2.21.47
167	10.2.21.48/29	10.2.21.49 – 10.2.21.54	10.2.21.55
168	10.2.21.56/29	10.2.21.57 – 10.2.21.62	10.2.21.63
169	10.2.21.64/29	10.2.21.65 – 10.2.21.70	10.2.21.71
170	10.2.21.72/29	10.2.21.73 – 10.2.21.78	10.2.21.79
171	10.2.21.80/29	10.2.21.81 – 10.2.21.86	10.2.21.87
172	10.2.21.88/29	10.2.21.89 – 10.2.21.94	10.2.21.95
173	10.2.21.96/29	10.2.21.97 – 10.2.21.102	10.2.21.103
174	10.2.21.104/29	10.2.21.105 – 10.2.21.110	10.2.21.111
175	10.2.21.112/29	10.2.21.113 – 10.2.21.118	10.2.21.119
176	10.2.21.120/29	10.2.21.121 – 10.2.21.126	10.2.21.127
177	10.2.21.128/29	10.2.21.129 – 10.2.21.134	10.2.21.135
178	10.2.21.136/29	10.2.21.137 – 10.2.21.142	10.2.21.143
179	10.2.21.144/29	10.2.21.145 – 10.2.21.150	10.2.21.151
180	10.2.21.152/29	10.2.21.153 – 10.2.21.158	10.2.21.159
181	10.2.21.160/29	10.2.21.161 – 10.2.21.166	10.2.21.167
182	10.2.21.168/29	10.2.21.169 – 10.2.21.174	10.2.21.175
183	10.2.21.176/29	10.2.21.177 – 10.2.21.182	10.2.21.183
184	10.2.21.184/29	10.2.21.185 – 10.2.21.190	10.2.21.191
185	10.2.21.192/29	10.2.21.193 – 10.2.21.198	10.2.21.199
186	10.2.21.200/29	10.2.21.201 – 10.2.21.206	10.2.21.207
187	10.2.21.208/29	10.2.21.209 – 10.2.21.214	10.2.21.215
188	10.2.21.216/29	10.2.21.217 – 10.2.21.222	10.2.21.223
189	10.2.21.224/29	10.2.21.225 – 10.2.21.230	10.2.21.231
190	10.2.21.232/29	10.2.21.233 – 10.2.21.238	10.2.21.239
191	10.2.21.240/29	10.2.21.241 – 10.2.21.246	10.2.21.247
192	10.2.21.248/29	10.2.21.249 – 10.2.21.254	10.2.21.255
193	10.2.22.0/29	10.2.22.1 – 10.2.22.6	10.2.22.7
194	10.2.22.8/29	10.2.22.9 – 10.2.22.14	10.2.22.15
195	10.2.22.16/29	10.2.22.17 – 10.2.22.22	10.2.22.23
196	10.2.22.24/29	10.2.22.25 – 10.2.22.30	10.2.22.31
197	10.2.22.32/29	10.2.22.33 – 10.2.22.38	10.2.22.39
198	10.2.22.40/29	10.2.22.41 – 10.2.22.46	10.2.22.47
199	10.2.22.48/29	10.2.22.49 – 10.2.22.54	10.2.22.55
200	10.2.22.56/29	10.2.22.57 – 10.2.22.62	10.2.22.63
201	10.2.22.64/29	10.2.22.65 – 10.2.22.70	10.2.22.71
202	10.2.22.72/29	10.2.22.73 – 10.2.22.78	10.2.22.79
203	10.2.22.80/29	10.2.22.81 – 10.2.22.86	10.2.22.87
204	10.2.22.88/29	10.2.22.89 – 10.2.22.94	10.2.22.95
205	10.2.22.96/29	10.2.22.97 – 10.2.22.102	10.2.22.103
206	10.2.22.104/29	10.2.22.105 – 10.2.22.110	10.2.22.111
207	10.2.22.112/29	10.2.22.113 – 10.2.22.118	10.2.22.119
208	10.2.22.120/29	10.2.22.121 – 10.2.22.126	10.2.22.127
209	10.2.22.128/29	10.2.22.129 – 10.2.22.134	10.2.22.135
210	10.2.22.136/29	10.2.22.137 – 10.2.22.142	10.2.22.143
211	10.2.22.144/29	10.2.22.145 – 10.2.22.150	10.2.22.151
212	10.2.22.152/29	10.2.22.153 – 10.2.22.158	10.2.22.159
213	10.2.22.160/29	10.2.22.161 – 10.2.22.166	10.2.22.167
214	10.2.22.168/29	10.2.22.169 – 10.2.22.174	10.2.22.175
215	10.2.22.176/29	10.2.22.177 – 10.2.22.182	10.2.22.183
216	10.2.22.184/29	10.2.22.185 – 10.2.22.190	10.2.22.191
217	10.2.22.192/29	10.2.22.193 – 10.2.22.198	10.2.22.199
218	10.2.22.200/29	10.2.22.201 – 10.2.22.206	10.2.22.207
219	10.2.22.208/29	10.2.22.209 – 10.2.22.214	10.2.22.215
220	10.2.22.216/29	10.2.22.217 – 10.2.22.222	10.2.22.223
221	10.2.22.224/29	10.2.22.225 – 10.2.22.230	10.2.22.231
222	10.2.22.232/29	10.2.22.233 – 10.2.22.238	10.2.22.239
223	10.2.22.240/29	10.2.22.241 – 10.2.22.246	10.2.22.247
224	10.2.22.248/29	10.2.22.249 – 10.2.22.254	10.2.22.255
225	10.2.23.0/29	10.2.23.1 – 10.2.23.6	10.2.23.7
226	10.2.23.8/29	10.2.23.9 – 10.2.23.14	10.2.23.15
227	10.2.23.16/29	10.2.23.17 – 10.2.23.22	10.2.23.23
228	10.2.23.24/29	10.2.23.25 – 10.2.23.30	10.2.23.31
229	10.2.23.32/29	10.2.23.33 – 10.2.23.38	10.2.23.39
230	10.2.23.40/29	10.2.23.41 – 10.2.23.46	10.2.23.47
231	10.2.23.48/29	10.2.23.49 – 10.2.23.54	10.2.23.55
232	10.2.23.56/29	10.2.23.57 – 10.2.23.62	10.2.23.63
233	10.2.23.64/29	10.2.23.65 – 10.2.23.70	10.2.23.71
234	10.2.23.72/29	10.2.23.73 – 10.2.23.78	10.2.23.79
235	10.2.23.80/29	10.2.23.81 – 10.2.23.86	10.2.23.87
236	10.2.23.88/29	10.2.23.89 – 10.2.23.94	10.2.23.95
237	10.2.23.96/29	10.2.23.97 – 10.2.23.102	10.2.23.103
238	10.2.23.104/29	10.2.23.105 – 10.2.23.110	10.2.23.111
239	10.2.23.112/29	10.2.23.113 – 10.2.23.118	10.2.23.119
240	10.2.23.120/29	10.2.23.121 – 10.2.23.126	10.2.23.127
241	10.2.23.128/29	10.2.23.129 – 10.2.23.134	10.2.23.135
242	10.2.23.136/29	10.2.23.137 – 10.2.23.142	10.2.23.143
243	10.2.23.144/29	10.2.23.145 – 10.2.23.150	10.2.23.151
244	10.2.23.152/29	10.2.23.153 – 10.2.23.158	10.2.23.159
245	10.2.23.160/29	10.2.23.161 – 10.2.23.166	10.2.23.167
246	10.2.23.168/29	10.2.23.169 – 10.2.23.174	10.2.23.175
247	10.2.23.176/29	10.2.23.177 – 10.2.23.182	10.2.23.183
248	10.2.23.184/29	10.2.23.185 – 10.2.23.190	10.2.23.191
249	10.2.23.192/29	10.2.23.193 – 10.2.23.198	10.2.23.199
250	10.2.23.200/29	10.2.23.201 – 10.2.23.206	10.2.23.207
251	10.2.23.208/29	10.2.23.209 – 10.2.23.214	10.2.23.215
252	10.2.23.216/29	10.2.23.217 – 10.2.23.222	10.2.23.223
253	10.2.23.224/29	10.2.23.225 – 10.2.23.230	10.2.23.231
254	10.2.23.232/29	10.2.23.233 – 10.2.23.238	10.2.23.239
255	10.2.23.240/29	10.2.23.241 – 10.2.23.246	10.2.23.247
256	10.2.23.248/29	10.2.23.249 – 10.2.23.254	10.2.23.255

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 →