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)10.5.64.0/21

network10.5.64.0/21

broadcast10.5.71.255

first host10.5.64.1

last host10.5.71.254

subnet mask255.255.248.0

wildcard0.0.7.255

addresses2,048

usable hosts2,046

classA

ipcalc 10.5.64.0/21

address00001010.00000101.01000000.00000000

subnet mask11111111.11111111.11111000.00000000

network00001010.00000101.01000000.00000000

broadcast00001010.00000101.01000111.11111111

green = network part, grey = host part

hex0x0a054000

decimal168116224

reverse dns0.64.5.10.in-addr.arpa

ipv4-mapped::ffff:a05:4000

/21 split into /29 · 256 subnets

close ×

#	network	host range	broadcast
1	10.5.64.0/29	10.5.64.1 – 10.5.64.6	10.5.64.7
2	10.5.64.8/29	10.5.64.9 – 10.5.64.14	10.5.64.15
3	10.5.64.16/29	10.5.64.17 – 10.5.64.22	10.5.64.23
4	10.5.64.24/29	10.5.64.25 – 10.5.64.30	10.5.64.31
5	10.5.64.32/29	10.5.64.33 – 10.5.64.38	10.5.64.39
6	10.5.64.40/29	10.5.64.41 – 10.5.64.46	10.5.64.47
7	10.5.64.48/29	10.5.64.49 – 10.5.64.54	10.5.64.55
8	10.5.64.56/29	10.5.64.57 – 10.5.64.62	10.5.64.63
9	10.5.64.64/29	10.5.64.65 – 10.5.64.70	10.5.64.71
10	10.5.64.72/29	10.5.64.73 – 10.5.64.78	10.5.64.79
11	10.5.64.80/29	10.5.64.81 – 10.5.64.86	10.5.64.87
12	10.5.64.88/29	10.5.64.89 – 10.5.64.94	10.5.64.95
13	10.5.64.96/29	10.5.64.97 – 10.5.64.102	10.5.64.103
14	10.5.64.104/29	10.5.64.105 – 10.5.64.110	10.5.64.111
15	10.5.64.112/29	10.5.64.113 – 10.5.64.118	10.5.64.119
16	10.5.64.120/29	10.5.64.121 – 10.5.64.126	10.5.64.127
17	10.5.64.128/29	10.5.64.129 – 10.5.64.134	10.5.64.135
18	10.5.64.136/29	10.5.64.137 – 10.5.64.142	10.5.64.143
19	10.5.64.144/29	10.5.64.145 – 10.5.64.150	10.5.64.151
20	10.5.64.152/29	10.5.64.153 – 10.5.64.158	10.5.64.159
21	10.5.64.160/29	10.5.64.161 – 10.5.64.166	10.5.64.167
22	10.5.64.168/29	10.5.64.169 – 10.5.64.174	10.5.64.175
23	10.5.64.176/29	10.5.64.177 – 10.5.64.182	10.5.64.183
24	10.5.64.184/29	10.5.64.185 – 10.5.64.190	10.5.64.191
25	10.5.64.192/29	10.5.64.193 – 10.5.64.198	10.5.64.199
26	10.5.64.200/29	10.5.64.201 – 10.5.64.206	10.5.64.207
27	10.5.64.208/29	10.5.64.209 – 10.5.64.214	10.5.64.215
28	10.5.64.216/29	10.5.64.217 – 10.5.64.222	10.5.64.223
29	10.5.64.224/29	10.5.64.225 – 10.5.64.230	10.5.64.231
30	10.5.64.232/29	10.5.64.233 – 10.5.64.238	10.5.64.239
31	10.5.64.240/29	10.5.64.241 – 10.5.64.246	10.5.64.247
32	10.5.64.248/29	10.5.64.249 – 10.5.64.254	10.5.64.255
33	10.5.65.0/29	10.5.65.1 – 10.5.65.6	10.5.65.7
34	10.5.65.8/29	10.5.65.9 – 10.5.65.14	10.5.65.15
35	10.5.65.16/29	10.5.65.17 – 10.5.65.22	10.5.65.23
36	10.5.65.24/29	10.5.65.25 – 10.5.65.30	10.5.65.31
37	10.5.65.32/29	10.5.65.33 – 10.5.65.38	10.5.65.39
38	10.5.65.40/29	10.5.65.41 – 10.5.65.46	10.5.65.47
39	10.5.65.48/29	10.5.65.49 – 10.5.65.54	10.5.65.55
40	10.5.65.56/29	10.5.65.57 – 10.5.65.62	10.5.65.63
41	10.5.65.64/29	10.5.65.65 – 10.5.65.70	10.5.65.71
42	10.5.65.72/29	10.5.65.73 – 10.5.65.78	10.5.65.79
43	10.5.65.80/29	10.5.65.81 – 10.5.65.86	10.5.65.87
44	10.5.65.88/29	10.5.65.89 – 10.5.65.94	10.5.65.95
45	10.5.65.96/29	10.5.65.97 – 10.5.65.102	10.5.65.103
46	10.5.65.104/29	10.5.65.105 – 10.5.65.110	10.5.65.111
47	10.5.65.112/29	10.5.65.113 – 10.5.65.118	10.5.65.119
48	10.5.65.120/29	10.5.65.121 – 10.5.65.126	10.5.65.127
49	10.5.65.128/29	10.5.65.129 – 10.5.65.134	10.5.65.135
50	10.5.65.136/29	10.5.65.137 – 10.5.65.142	10.5.65.143
51	10.5.65.144/29	10.5.65.145 – 10.5.65.150	10.5.65.151
52	10.5.65.152/29	10.5.65.153 – 10.5.65.158	10.5.65.159
53	10.5.65.160/29	10.5.65.161 – 10.5.65.166	10.5.65.167
54	10.5.65.168/29	10.5.65.169 – 10.5.65.174	10.5.65.175
55	10.5.65.176/29	10.5.65.177 – 10.5.65.182	10.5.65.183
56	10.5.65.184/29	10.5.65.185 – 10.5.65.190	10.5.65.191
57	10.5.65.192/29	10.5.65.193 – 10.5.65.198	10.5.65.199
58	10.5.65.200/29	10.5.65.201 – 10.5.65.206	10.5.65.207
59	10.5.65.208/29	10.5.65.209 – 10.5.65.214	10.5.65.215
60	10.5.65.216/29	10.5.65.217 – 10.5.65.222	10.5.65.223
61	10.5.65.224/29	10.5.65.225 – 10.5.65.230	10.5.65.231
62	10.5.65.232/29	10.5.65.233 – 10.5.65.238	10.5.65.239
63	10.5.65.240/29	10.5.65.241 – 10.5.65.246	10.5.65.247
64	10.5.65.248/29	10.5.65.249 – 10.5.65.254	10.5.65.255
65	10.5.66.0/29	10.5.66.1 – 10.5.66.6	10.5.66.7
66	10.5.66.8/29	10.5.66.9 – 10.5.66.14	10.5.66.15
67	10.5.66.16/29	10.5.66.17 – 10.5.66.22	10.5.66.23
68	10.5.66.24/29	10.5.66.25 – 10.5.66.30	10.5.66.31
69	10.5.66.32/29	10.5.66.33 – 10.5.66.38	10.5.66.39
70	10.5.66.40/29	10.5.66.41 – 10.5.66.46	10.5.66.47
71	10.5.66.48/29	10.5.66.49 – 10.5.66.54	10.5.66.55
72	10.5.66.56/29	10.5.66.57 – 10.5.66.62	10.5.66.63
73	10.5.66.64/29	10.5.66.65 – 10.5.66.70	10.5.66.71
74	10.5.66.72/29	10.5.66.73 – 10.5.66.78	10.5.66.79
75	10.5.66.80/29	10.5.66.81 – 10.5.66.86	10.5.66.87
76	10.5.66.88/29	10.5.66.89 – 10.5.66.94	10.5.66.95
77	10.5.66.96/29	10.5.66.97 – 10.5.66.102	10.5.66.103
78	10.5.66.104/29	10.5.66.105 – 10.5.66.110	10.5.66.111
79	10.5.66.112/29	10.5.66.113 – 10.5.66.118	10.5.66.119
80	10.5.66.120/29	10.5.66.121 – 10.5.66.126	10.5.66.127
81	10.5.66.128/29	10.5.66.129 – 10.5.66.134	10.5.66.135
82	10.5.66.136/29	10.5.66.137 – 10.5.66.142	10.5.66.143
83	10.5.66.144/29	10.5.66.145 – 10.5.66.150	10.5.66.151
84	10.5.66.152/29	10.5.66.153 – 10.5.66.158	10.5.66.159
85	10.5.66.160/29	10.5.66.161 – 10.5.66.166	10.5.66.167
86	10.5.66.168/29	10.5.66.169 – 10.5.66.174	10.5.66.175
87	10.5.66.176/29	10.5.66.177 – 10.5.66.182	10.5.66.183
88	10.5.66.184/29	10.5.66.185 – 10.5.66.190	10.5.66.191
89	10.5.66.192/29	10.5.66.193 – 10.5.66.198	10.5.66.199
90	10.5.66.200/29	10.5.66.201 – 10.5.66.206	10.5.66.207
91	10.5.66.208/29	10.5.66.209 – 10.5.66.214	10.5.66.215
92	10.5.66.216/29	10.5.66.217 – 10.5.66.222	10.5.66.223
93	10.5.66.224/29	10.5.66.225 – 10.5.66.230	10.5.66.231
94	10.5.66.232/29	10.5.66.233 – 10.5.66.238	10.5.66.239
95	10.5.66.240/29	10.5.66.241 – 10.5.66.246	10.5.66.247
96	10.5.66.248/29	10.5.66.249 – 10.5.66.254	10.5.66.255
97	10.5.67.0/29	10.5.67.1 – 10.5.67.6	10.5.67.7
98	10.5.67.8/29	10.5.67.9 – 10.5.67.14	10.5.67.15
99	10.5.67.16/29	10.5.67.17 – 10.5.67.22	10.5.67.23
100	10.5.67.24/29	10.5.67.25 – 10.5.67.30	10.5.67.31
101	10.5.67.32/29	10.5.67.33 – 10.5.67.38	10.5.67.39
102	10.5.67.40/29	10.5.67.41 – 10.5.67.46	10.5.67.47
103	10.5.67.48/29	10.5.67.49 – 10.5.67.54	10.5.67.55
104	10.5.67.56/29	10.5.67.57 – 10.5.67.62	10.5.67.63
105	10.5.67.64/29	10.5.67.65 – 10.5.67.70	10.5.67.71
106	10.5.67.72/29	10.5.67.73 – 10.5.67.78	10.5.67.79
107	10.5.67.80/29	10.5.67.81 – 10.5.67.86	10.5.67.87
108	10.5.67.88/29	10.5.67.89 – 10.5.67.94	10.5.67.95
109	10.5.67.96/29	10.5.67.97 – 10.5.67.102	10.5.67.103
110	10.5.67.104/29	10.5.67.105 – 10.5.67.110	10.5.67.111
111	10.5.67.112/29	10.5.67.113 – 10.5.67.118	10.5.67.119
112	10.5.67.120/29	10.5.67.121 – 10.5.67.126	10.5.67.127
113	10.5.67.128/29	10.5.67.129 – 10.5.67.134	10.5.67.135
114	10.5.67.136/29	10.5.67.137 – 10.5.67.142	10.5.67.143
115	10.5.67.144/29	10.5.67.145 – 10.5.67.150	10.5.67.151
116	10.5.67.152/29	10.5.67.153 – 10.5.67.158	10.5.67.159
117	10.5.67.160/29	10.5.67.161 – 10.5.67.166	10.5.67.167
118	10.5.67.168/29	10.5.67.169 – 10.5.67.174	10.5.67.175
119	10.5.67.176/29	10.5.67.177 – 10.5.67.182	10.5.67.183
120	10.5.67.184/29	10.5.67.185 – 10.5.67.190	10.5.67.191
121	10.5.67.192/29	10.5.67.193 – 10.5.67.198	10.5.67.199
122	10.5.67.200/29	10.5.67.201 – 10.5.67.206	10.5.67.207
123	10.5.67.208/29	10.5.67.209 – 10.5.67.214	10.5.67.215
124	10.5.67.216/29	10.5.67.217 – 10.5.67.222	10.5.67.223
125	10.5.67.224/29	10.5.67.225 – 10.5.67.230	10.5.67.231
126	10.5.67.232/29	10.5.67.233 – 10.5.67.238	10.5.67.239
127	10.5.67.240/29	10.5.67.241 – 10.5.67.246	10.5.67.247
128	10.5.67.248/29	10.5.67.249 – 10.5.67.254	10.5.67.255
129	10.5.68.0/29	10.5.68.1 – 10.5.68.6	10.5.68.7
130	10.5.68.8/29	10.5.68.9 – 10.5.68.14	10.5.68.15
131	10.5.68.16/29	10.5.68.17 – 10.5.68.22	10.5.68.23
132	10.5.68.24/29	10.5.68.25 – 10.5.68.30	10.5.68.31
133	10.5.68.32/29	10.5.68.33 – 10.5.68.38	10.5.68.39
134	10.5.68.40/29	10.5.68.41 – 10.5.68.46	10.5.68.47
135	10.5.68.48/29	10.5.68.49 – 10.5.68.54	10.5.68.55
136	10.5.68.56/29	10.5.68.57 – 10.5.68.62	10.5.68.63
137	10.5.68.64/29	10.5.68.65 – 10.5.68.70	10.5.68.71
138	10.5.68.72/29	10.5.68.73 – 10.5.68.78	10.5.68.79
139	10.5.68.80/29	10.5.68.81 – 10.5.68.86	10.5.68.87
140	10.5.68.88/29	10.5.68.89 – 10.5.68.94	10.5.68.95
141	10.5.68.96/29	10.5.68.97 – 10.5.68.102	10.5.68.103
142	10.5.68.104/29	10.5.68.105 – 10.5.68.110	10.5.68.111
143	10.5.68.112/29	10.5.68.113 – 10.5.68.118	10.5.68.119
144	10.5.68.120/29	10.5.68.121 – 10.5.68.126	10.5.68.127
145	10.5.68.128/29	10.5.68.129 – 10.5.68.134	10.5.68.135
146	10.5.68.136/29	10.5.68.137 – 10.5.68.142	10.5.68.143
147	10.5.68.144/29	10.5.68.145 – 10.5.68.150	10.5.68.151
148	10.5.68.152/29	10.5.68.153 – 10.5.68.158	10.5.68.159
149	10.5.68.160/29	10.5.68.161 – 10.5.68.166	10.5.68.167
150	10.5.68.168/29	10.5.68.169 – 10.5.68.174	10.5.68.175
151	10.5.68.176/29	10.5.68.177 – 10.5.68.182	10.5.68.183
152	10.5.68.184/29	10.5.68.185 – 10.5.68.190	10.5.68.191
153	10.5.68.192/29	10.5.68.193 – 10.5.68.198	10.5.68.199
154	10.5.68.200/29	10.5.68.201 – 10.5.68.206	10.5.68.207
155	10.5.68.208/29	10.5.68.209 – 10.5.68.214	10.5.68.215
156	10.5.68.216/29	10.5.68.217 – 10.5.68.222	10.5.68.223
157	10.5.68.224/29	10.5.68.225 – 10.5.68.230	10.5.68.231
158	10.5.68.232/29	10.5.68.233 – 10.5.68.238	10.5.68.239
159	10.5.68.240/29	10.5.68.241 – 10.5.68.246	10.5.68.247
160	10.5.68.248/29	10.5.68.249 – 10.5.68.254	10.5.68.255
161	10.5.69.0/29	10.5.69.1 – 10.5.69.6	10.5.69.7
162	10.5.69.8/29	10.5.69.9 – 10.5.69.14	10.5.69.15
163	10.5.69.16/29	10.5.69.17 – 10.5.69.22	10.5.69.23
164	10.5.69.24/29	10.5.69.25 – 10.5.69.30	10.5.69.31
165	10.5.69.32/29	10.5.69.33 – 10.5.69.38	10.5.69.39
166	10.5.69.40/29	10.5.69.41 – 10.5.69.46	10.5.69.47
167	10.5.69.48/29	10.5.69.49 – 10.5.69.54	10.5.69.55
168	10.5.69.56/29	10.5.69.57 – 10.5.69.62	10.5.69.63
169	10.5.69.64/29	10.5.69.65 – 10.5.69.70	10.5.69.71
170	10.5.69.72/29	10.5.69.73 – 10.5.69.78	10.5.69.79
171	10.5.69.80/29	10.5.69.81 – 10.5.69.86	10.5.69.87
172	10.5.69.88/29	10.5.69.89 – 10.5.69.94	10.5.69.95
173	10.5.69.96/29	10.5.69.97 – 10.5.69.102	10.5.69.103
174	10.5.69.104/29	10.5.69.105 – 10.5.69.110	10.5.69.111
175	10.5.69.112/29	10.5.69.113 – 10.5.69.118	10.5.69.119
176	10.5.69.120/29	10.5.69.121 – 10.5.69.126	10.5.69.127
177	10.5.69.128/29	10.5.69.129 – 10.5.69.134	10.5.69.135
178	10.5.69.136/29	10.5.69.137 – 10.5.69.142	10.5.69.143
179	10.5.69.144/29	10.5.69.145 – 10.5.69.150	10.5.69.151
180	10.5.69.152/29	10.5.69.153 – 10.5.69.158	10.5.69.159
181	10.5.69.160/29	10.5.69.161 – 10.5.69.166	10.5.69.167
182	10.5.69.168/29	10.5.69.169 – 10.5.69.174	10.5.69.175
183	10.5.69.176/29	10.5.69.177 – 10.5.69.182	10.5.69.183
184	10.5.69.184/29	10.5.69.185 – 10.5.69.190	10.5.69.191
185	10.5.69.192/29	10.5.69.193 – 10.5.69.198	10.5.69.199
186	10.5.69.200/29	10.5.69.201 – 10.5.69.206	10.5.69.207
187	10.5.69.208/29	10.5.69.209 – 10.5.69.214	10.5.69.215
188	10.5.69.216/29	10.5.69.217 – 10.5.69.222	10.5.69.223
189	10.5.69.224/29	10.5.69.225 – 10.5.69.230	10.5.69.231
190	10.5.69.232/29	10.5.69.233 – 10.5.69.238	10.5.69.239
191	10.5.69.240/29	10.5.69.241 – 10.5.69.246	10.5.69.247
192	10.5.69.248/29	10.5.69.249 – 10.5.69.254	10.5.69.255
193	10.5.70.0/29	10.5.70.1 – 10.5.70.6	10.5.70.7
194	10.5.70.8/29	10.5.70.9 – 10.5.70.14	10.5.70.15
195	10.5.70.16/29	10.5.70.17 – 10.5.70.22	10.5.70.23
196	10.5.70.24/29	10.5.70.25 – 10.5.70.30	10.5.70.31
197	10.5.70.32/29	10.5.70.33 – 10.5.70.38	10.5.70.39
198	10.5.70.40/29	10.5.70.41 – 10.5.70.46	10.5.70.47
199	10.5.70.48/29	10.5.70.49 – 10.5.70.54	10.5.70.55
200	10.5.70.56/29	10.5.70.57 – 10.5.70.62	10.5.70.63
201	10.5.70.64/29	10.5.70.65 – 10.5.70.70	10.5.70.71
202	10.5.70.72/29	10.5.70.73 – 10.5.70.78	10.5.70.79
203	10.5.70.80/29	10.5.70.81 – 10.5.70.86	10.5.70.87
204	10.5.70.88/29	10.5.70.89 – 10.5.70.94	10.5.70.95
205	10.5.70.96/29	10.5.70.97 – 10.5.70.102	10.5.70.103
206	10.5.70.104/29	10.5.70.105 – 10.5.70.110	10.5.70.111
207	10.5.70.112/29	10.5.70.113 – 10.5.70.118	10.5.70.119
208	10.5.70.120/29	10.5.70.121 – 10.5.70.126	10.5.70.127
209	10.5.70.128/29	10.5.70.129 – 10.5.70.134	10.5.70.135
210	10.5.70.136/29	10.5.70.137 – 10.5.70.142	10.5.70.143
211	10.5.70.144/29	10.5.70.145 – 10.5.70.150	10.5.70.151
212	10.5.70.152/29	10.5.70.153 – 10.5.70.158	10.5.70.159
213	10.5.70.160/29	10.5.70.161 – 10.5.70.166	10.5.70.167
214	10.5.70.168/29	10.5.70.169 – 10.5.70.174	10.5.70.175
215	10.5.70.176/29	10.5.70.177 – 10.5.70.182	10.5.70.183
216	10.5.70.184/29	10.5.70.185 – 10.5.70.190	10.5.70.191
217	10.5.70.192/29	10.5.70.193 – 10.5.70.198	10.5.70.199
218	10.5.70.200/29	10.5.70.201 – 10.5.70.206	10.5.70.207
219	10.5.70.208/29	10.5.70.209 – 10.5.70.214	10.5.70.215
220	10.5.70.216/29	10.5.70.217 – 10.5.70.222	10.5.70.223
221	10.5.70.224/29	10.5.70.225 – 10.5.70.230	10.5.70.231
222	10.5.70.232/29	10.5.70.233 – 10.5.70.238	10.5.70.239
223	10.5.70.240/29	10.5.70.241 – 10.5.70.246	10.5.70.247
224	10.5.70.248/29	10.5.70.249 – 10.5.70.254	10.5.70.255
225	10.5.71.0/29	10.5.71.1 – 10.5.71.6	10.5.71.7
226	10.5.71.8/29	10.5.71.9 – 10.5.71.14	10.5.71.15
227	10.5.71.16/29	10.5.71.17 – 10.5.71.22	10.5.71.23
228	10.5.71.24/29	10.5.71.25 – 10.5.71.30	10.5.71.31
229	10.5.71.32/29	10.5.71.33 – 10.5.71.38	10.5.71.39
230	10.5.71.40/29	10.5.71.41 – 10.5.71.46	10.5.71.47
231	10.5.71.48/29	10.5.71.49 – 10.5.71.54	10.5.71.55
232	10.5.71.56/29	10.5.71.57 – 10.5.71.62	10.5.71.63
233	10.5.71.64/29	10.5.71.65 – 10.5.71.70	10.5.71.71
234	10.5.71.72/29	10.5.71.73 – 10.5.71.78	10.5.71.79
235	10.5.71.80/29	10.5.71.81 – 10.5.71.86	10.5.71.87
236	10.5.71.88/29	10.5.71.89 – 10.5.71.94	10.5.71.95
237	10.5.71.96/29	10.5.71.97 – 10.5.71.102	10.5.71.103
238	10.5.71.104/29	10.5.71.105 – 10.5.71.110	10.5.71.111
239	10.5.71.112/29	10.5.71.113 – 10.5.71.118	10.5.71.119
240	10.5.71.120/29	10.5.71.121 – 10.5.71.126	10.5.71.127
241	10.5.71.128/29	10.5.71.129 – 10.5.71.134	10.5.71.135
242	10.5.71.136/29	10.5.71.137 – 10.5.71.142	10.5.71.143
243	10.5.71.144/29	10.5.71.145 – 10.5.71.150	10.5.71.151
244	10.5.71.152/29	10.5.71.153 – 10.5.71.158	10.5.71.159
245	10.5.71.160/29	10.5.71.161 – 10.5.71.166	10.5.71.167
246	10.5.71.168/29	10.5.71.169 – 10.5.71.174	10.5.71.175
247	10.5.71.176/29	10.5.71.177 – 10.5.71.182	10.5.71.183
248	10.5.71.184/29	10.5.71.185 – 10.5.71.190	10.5.71.191
249	10.5.71.192/29	10.5.71.193 – 10.5.71.198	10.5.71.199
250	10.5.71.200/29	10.5.71.201 – 10.5.71.206	10.5.71.207
251	10.5.71.208/29	10.5.71.209 – 10.5.71.214	10.5.71.215
252	10.5.71.216/29	10.5.71.217 – 10.5.71.222	10.5.71.223
253	10.5.71.224/29	10.5.71.225 – 10.5.71.230	10.5.71.231
254	10.5.71.232/29	10.5.71.233 – 10.5.71.238	10.5.71.239
255	10.5.71.240/29	10.5.71.241 – 10.5.71.246	10.5.71.247
256	10.5.71.248/29	10.5.71.249 – 10.5.71.254	10.5.71.255

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 →