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)10.2.168.0/21

network10.2.168.0/21

broadcast10.2.175.255

first host10.2.168.1

last host10.2.175.254

subnet mask255.255.248.0

wildcard0.0.7.255

addresses2,048

usable hosts2,046

classA

ipcalc 10.2.168.0/21

address00001010.00000010.10101000.00000000

subnet mask11111111.11111111.11111000.00000000

network00001010.00000010.10101000.00000000

broadcast00001010.00000010.10101111.11111111

green = network part, grey = host part

hex0x0a02a800

decimal167946240

reverse dns0.168.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:a800

/21 split into /29 · 256 subnets

close ×

#	network	host range	broadcast
1	10.2.168.0/29	10.2.168.1 – 10.2.168.6	10.2.168.7
2	10.2.168.8/29	10.2.168.9 – 10.2.168.14	10.2.168.15
3	10.2.168.16/29	10.2.168.17 – 10.2.168.22	10.2.168.23
4	10.2.168.24/29	10.2.168.25 – 10.2.168.30	10.2.168.31
5	10.2.168.32/29	10.2.168.33 – 10.2.168.38	10.2.168.39
6	10.2.168.40/29	10.2.168.41 – 10.2.168.46	10.2.168.47
7	10.2.168.48/29	10.2.168.49 – 10.2.168.54	10.2.168.55
8	10.2.168.56/29	10.2.168.57 – 10.2.168.62	10.2.168.63
9	10.2.168.64/29	10.2.168.65 – 10.2.168.70	10.2.168.71
10	10.2.168.72/29	10.2.168.73 – 10.2.168.78	10.2.168.79
11	10.2.168.80/29	10.2.168.81 – 10.2.168.86	10.2.168.87
12	10.2.168.88/29	10.2.168.89 – 10.2.168.94	10.2.168.95
13	10.2.168.96/29	10.2.168.97 – 10.2.168.102	10.2.168.103
14	10.2.168.104/29	10.2.168.105 – 10.2.168.110	10.2.168.111
15	10.2.168.112/29	10.2.168.113 – 10.2.168.118	10.2.168.119
16	10.2.168.120/29	10.2.168.121 – 10.2.168.126	10.2.168.127
17	10.2.168.128/29	10.2.168.129 – 10.2.168.134	10.2.168.135
18	10.2.168.136/29	10.2.168.137 – 10.2.168.142	10.2.168.143
19	10.2.168.144/29	10.2.168.145 – 10.2.168.150	10.2.168.151
20	10.2.168.152/29	10.2.168.153 – 10.2.168.158	10.2.168.159
21	10.2.168.160/29	10.2.168.161 – 10.2.168.166	10.2.168.167
22	10.2.168.168/29	10.2.168.169 – 10.2.168.174	10.2.168.175
23	10.2.168.176/29	10.2.168.177 – 10.2.168.182	10.2.168.183
24	10.2.168.184/29	10.2.168.185 – 10.2.168.190	10.2.168.191
25	10.2.168.192/29	10.2.168.193 – 10.2.168.198	10.2.168.199
26	10.2.168.200/29	10.2.168.201 – 10.2.168.206	10.2.168.207
27	10.2.168.208/29	10.2.168.209 – 10.2.168.214	10.2.168.215
28	10.2.168.216/29	10.2.168.217 – 10.2.168.222	10.2.168.223
29	10.2.168.224/29	10.2.168.225 – 10.2.168.230	10.2.168.231
30	10.2.168.232/29	10.2.168.233 – 10.2.168.238	10.2.168.239
31	10.2.168.240/29	10.2.168.241 – 10.2.168.246	10.2.168.247
32	10.2.168.248/29	10.2.168.249 – 10.2.168.254	10.2.168.255
33	10.2.169.0/29	10.2.169.1 – 10.2.169.6	10.2.169.7
34	10.2.169.8/29	10.2.169.9 – 10.2.169.14	10.2.169.15
35	10.2.169.16/29	10.2.169.17 – 10.2.169.22	10.2.169.23
36	10.2.169.24/29	10.2.169.25 – 10.2.169.30	10.2.169.31
37	10.2.169.32/29	10.2.169.33 – 10.2.169.38	10.2.169.39
38	10.2.169.40/29	10.2.169.41 – 10.2.169.46	10.2.169.47
39	10.2.169.48/29	10.2.169.49 – 10.2.169.54	10.2.169.55
40	10.2.169.56/29	10.2.169.57 – 10.2.169.62	10.2.169.63
41	10.2.169.64/29	10.2.169.65 – 10.2.169.70	10.2.169.71
42	10.2.169.72/29	10.2.169.73 – 10.2.169.78	10.2.169.79
43	10.2.169.80/29	10.2.169.81 – 10.2.169.86	10.2.169.87
44	10.2.169.88/29	10.2.169.89 – 10.2.169.94	10.2.169.95
45	10.2.169.96/29	10.2.169.97 – 10.2.169.102	10.2.169.103
46	10.2.169.104/29	10.2.169.105 – 10.2.169.110	10.2.169.111
47	10.2.169.112/29	10.2.169.113 – 10.2.169.118	10.2.169.119
48	10.2.169.120/29	10.2.169.121 – 10.2.169.126	10.2.169.127
49	10.2.169.128/29	10.2.169.129 – 10.2.169.134	10.2.169.135
50	10.2.169.136/29	10.2.169.137 – 10.2.169.142	10.2.169.143
51	10.2.169.144/29	10.2.169.145 – 10.2.169.150	10.2.169.151
52	10.2.169.152/29	10.2.169.153 – 10.2.169.158	10.2.169.159
53	10.2.169.160/29	10.2.169.161 – 10.2.169.166	10.2.169.167
54	10.2.169.168/29	10.2.169.169 – 10.2.169.174	10.2.169.175
55	10.2.169.176/29	10.2.169.177 – 10.2.169.182	10.2.169.183
56	10.2.169.184/29	10.2.169.185 – 10.2.169.190	10.2.169.191
57	10.2.169.192/29	10.2.169.193 – 10.2.169.198	10.2.169.199
58	10.2.169.200/29	10.2.169.201 – 10.2.169.206	10.2.169.207
59	10.2.169.208/29	10.2.169.209 – 10.2.169.214	10.2.169.215
60	10.2.169.216/29	10.2.169.217 – 10.2.169.222	10.2.169.223
61	10.2.169.224/29	10.2.169.225 – 10.2.169.230	10.2.169.231
62	10.2.169.232/29	10.2.169.233 – 10.2.169.238	10.2.169.239
63	10.2.169.240/29	10.2.169.241 – 10.2.169.246	10.2.169.247
64	10.2.169.248/29	10.2.169.249 – 10.2.169.254	10.2.169.255
65	10.2.170.0/29	10.2.170.1 – 10.2.170.6	10.2.170.7
66	10.2.170.8/29	10.2.170.9 – 10.2.170.14	10.2.170.15
67	10.2.170.16/29	10.2.170.17 – 10.2.170.22	10.2.170.23
68	10.2.170.24/29	10.2.170.25 – 10.2.170.30	10.2.170.31
69	10.2.170.32/29	10.2.170.33 – 10.2.170.38	10.2.170.39
70	10.2.170.40/29	10.2.170.41 – 10.2.170.46	10.2.170.47
71	10.2.170.48/29	10.2.170.49 – 10.2.170.54	10.2.170.55
72	10.2.170.56/29	10.2.170.57 – 10.2.170.62	10.2.170.63
73	10.2.170.64/29	10.2.170.65 – 10.2.170.70	10.2.170.71
74	10.2.170.72/29	10.2.170.73 – 10.2.170.78	10.2.170.79
75	10.2.170.80/29	10.2.170.81 – 10.2.170.86	10.2.170.87
76	10.2.170.88/29	10.2.170.89 – 10.2.170.94	10.2.170.95
77	10.2.170.96/29	10.2.170.97 – 10.2.170.102	10.2.170.103
78	10.2.170.104/29	10.2.170.105 – 10.2.170.110	10.2.170.111
79	10.2.170.112/29	10.2.170.113 – 10.2.170.118	10.2.170.119
80	10.2.170.120/29	10.2.170.121 – 10.2.170.126	10.2.170.127
81	10.2.170.128/29	10.2.170.129 – 10.2.170.134	10.2.170.135
82	10.2.170.136/29	10.2.170.137 – 10.2.170.142	10.2.170.143
83	10.2.170.144/29	10.2.170.145 – 10.2.170.150	10.2.170.151
84	10.2.170.152/29	10.2.170.153 – 10.2.170.158	10.2.170.159
85	10.2.170.160/29	10.2.170.161 – 10.2.170.166	10.2.170.167
86	10.2.170.168/29	10.2.170.169 – 10.2.170.174	10.2.170.175
87	10.2.170.176/29	10.2.170.177 – 10.2.170.182	10.2.170.183
88	10.2.170.184/29	10.2.170.185 – 10.2.170.190	10.2.170.191
89	10.2.170.192/29	10.2.170.193 – 10.2.170.198	10.2.170.199
90	10.2.170.200/29	10.2.170.201 – 10.2.170.206	10.2.170.207
91	10.2.170.208/29	10.2.170.209 – 10.2.170.214	10.2.170.215
92	10.2.170.216/29	10.2.170.217 – 10.2.170.222	10.2.170.223
93	10.2.170.224/29	10.2.170.225 – 10.2.170.230	10.2.170.231
94	10.2.170.232/29	10.2.170.233 – 10.2.170.238	10.2.170.239
95	10.2.170.240/29	10.2.170.241 – 10.2.170.246	10.2.170.247
96	10.2.170.248/29	10.2.170.249 – 10.2.170.254	10.2.170.255
97	10.2.171.0/29	10.2.171.1 – 10.2.171.6	10.2.171.7
98	10.2.171.8/29	10.2.171.9 – 10.2.171.14	10.2.171.15
99	10.2.171.16/29	10.2.171.17 – 10.2.171.22	10.2.171.23
100	10.2.171.24/29	10.2.171.25 – 10.2.171.30	10.2.171.31
101	10.2.171.32/29	10.2.171.33 – 10.2.171.38	10.2.171.39
102	10.2.171.40/29	10.2.171.41 – 10.2.171.46	10.2.171.47
103	10.2.171.48/29	10.2.171.49 – 10.2.171.54	10.2.171.55
104	10.2.171.56/29	10.2.171.57 – 10.2.171.62	10.2.171.63
105	10.2.171.64/29	10.2.171.65 – 10.2.171.70	10.2.171.71
106	10.2.171.72/29	10.2.171.73 – 10.2.171.78	10.2.171.79
107	10.2.171.80/29	10.2.171.81 – 10.2.171.86	10.2.171.87
108	10.2.171.88/29	10.2.171.89 – 10.2.171.94	10.2.171.95
109	10.2.171.96/29	10.2.171.97 – 10.2.171.102	10.2.171.103
110	10.2.171.104/29	10.2.171.105 – 10.2.171.110	10.2.171.111
111	10.2.171.112/29	10.2.171.113 – 10.2.171.118	10.2.171.119
112	10.2.171.120/29	10.2.171.121 – 10.2.171.126	10.2.171.127
113	10.2.171.128/29	10.2.171.129 – 10.2.171.134	10.2.171.135
114	10.2.171.136/29	10.2.171.137 – 10.2.171.142	10.2.171.143
115	10.2.171.144/29	10.2.171.145 – 10.2.171.150	10.2.171.151
116	10.2.171.152/29	10.2.171.153 – 10.2.171.158	10.2.171.159
117	10.2.171.160/29	10.2.171.161 – 10.2.171.166	10.2.171.167
118	10.2.171.168/29	10.2.171.169 – 10.2.171.174	10.2.171.175
119	10.2.171.176/29	10.2.171.177 – 10.2.171.182	10.2.171.183
120	10.2.171.184/29	10.2.171.185 – 10.2.171.190	10.2.171.191
121	10.2.171.192/29	10.2.171.193 – 10.2.171.198	10.2.171.199
122	10.2.171.200/29	10.2.171.201 – 10.2.171.206	10.2.171.207
123	10.2.171.208/29	10.2.171.209 – 10.2.171.214	10.2.171.215
124	10.2.171.216/29	10.2.171.217 – 10.2.171.222	10.2.171.223
125	10.2.171.224/29	10.2.171.225 – 10.2.171.230	10.2.171.231
126	10.2.171.232/29	10.2.171.233 – 10.2.171.238	10.2.171.239
127	10.2.171.240/29	10.2.171.241 – 10.2.171.246	10.2.171.247
128	10.2.171.248/29	10.2.171.249 – 10.2.171.254	10.2.171.255
129	10.2.172.0/29	10.2.172.1 – 10.2.172.6	10.2.172.7
130	10.2.172.8/29	10.2.172.9 – 10.2.172.14	10.2.172.15
131	10.2.172.16/29	10.2.172.17 – 10.2.172.22	10.2.172.23
132	10.2.172.24/29	10.2.172.25 – 10.2.172.30	10.2.172.31
133	10.2.172.32/29	10.2.172.33 – 10.2.172.38	10.2.172.39
134	10.2.172.40/29	10.2.172.41 – 10.2.172.46	10.2.172.47
135	10.2.172.48/29	10.2.172.49 – 10.2.172.54	10.2.172.55
136	10.2.172.56/29	10.2.172.57 – 10.2.172.62	10.2.172.63
137	10.2.172.64/29	10.2.172.65 – 10.2.172.70	10.2.172.71
138	10.2.172.72/29	10.2.172.73 – 10.2.172.78	10.2.172.79
139	10.2.172.80/29	10.2.172.81 – 10.2.172.86	10.2.172.87
140	10.2.172.88/29	10.2.172.89 – 10.2.172.94	10.2.172.95
141	10.2.172.96/29	10.2.172.97 – 10.2.172.102	10.2.172.103
142	10.2.172.104/29	10.2.172.105 – 10.2.172.110	10.2.172.111
143	10.2.172.112/29	10.2.172.113 – 10.2.172.118	10.2.172.119
144	10.2.172.120/29	10.2.172.121 – 10.2.172.126	10.2.172.127
145	10.2.172.128/29	10.2.172.129 – 10.2.172.134	10.2.172.135
146	10.2.172.136/29	10.2.172.137 – 10.2.172.142	10.2.172.143
147	10.2.172.144/29	10.2.172.145 – 10.2.172.150	10.2.172.151
148	10.2.172.152/29	10.2.172.153 – 10.2.172.158	10.2.172.159
149	10.2.172.160/29	10.2.172.161 – 10.2.172.166	10.2.172.167
150	10.2.172.168/29	10.2.172.169 – 10.2.172.174	10.2.172.175
151	10.2.172.176/29	10.2.172.177 – 10.2.172.182	10.2.172.183
152	10.2.172.184/29	10.2.172.185 – 10.2.172.190	10.2.172.191
153	10.2.172.192/29	10.2.172.193 – 10.2.172.198	10.2.172.199
154	10.2.172.200/29	10.2.172.201 – 10.2.172.206	10.2.172.207
155	10.2.172.208/29	10.2.172.209 – 10.2.172.214	10.2.172.215
156	10.2.172.216/29	10.2.172.217 – 10.2.172.222	10.2.172.223
157	10.2.172.224/29	10.2.172.225 – 10.2.172.230	10.2.172.231
158	10.2.172.232/29	10.2.172.233 – 10.2.172.238	10.2.172.239
159	10.2.172.240/29	10.2.172.241 – 10.2.172.246	10.2.172.247
160	10.2.172.248/29	10.2.172.249 – 10.2.172.254	10.2.172.255
161	10.2.173.0/29	10.2.173.1 – 10.2.173.6	10.2.173.7
162	10.2.173.8/29	10.2.173.9 – 10.2.173.14	10.2.173.15
163	10.2.173.16/29	10.2.173.17 – 10.2.173.22	10.2.173.23
164	10.2.173.24/29	10.2.173.25 – 10.2.173.30	10.2.173.31
165	10.2.173.32/29	10.2.173.33 – 10.2.173.38	10.2.173.39
166	10.2.173.40/29	10.2.173.41 – 10.2.173.46	10.2.173.47
167	10.2.173.48/29	10.2.173.49 – 10.2.173.54	10.2.173.55
168	10.2.173.56/29	10.2.173.57 – 10.2.173.62	10.2.173.63
169	10.2.173.64/29	10.2.173.65 – 10.2.173.70	10.2.173.71
170	10.2.173.72/29	10.2.173.73 – 10.2.173.78	10.2.173.79
171	10.2.173.80/29	10.2.173.81 – 10.2.173.86	10.2.173.87
172	10.2.173.88/29	10.2.173.89 – 10.2.173.94	10.2.173.95
173	10.2.173.96/29	10.2.173.97 – 10.2.173.102	10.2.173.103
174	10.2.173.104/29	10.2.173.105 – 10.2.173.110	10.2.173.111
175	10.2.173.112/29	10.2.173.113 – 10.2.173.118	10.2.173.119
176	10.2.173.120/29	10.2.173.121 – 10.2.173.126	10.2.173.127
177	10.2.173.128/29	10.2.173.129 – 10.2.173.134	10.2.173.135
178	10.2.173.136/29	10.2.173.137 – 10.2.173.142	10.2.173.143
179	10.2.173.144/29	10.2.173.145 – 10.2.173.150	10.2.173.151
180	10.2.173.152/29	10.2.173.153 – 10.2.173.158	10.2.173.159
181	10.2.173.160/29	10.2.173.161 – 10.2.173.166	10.2.173.167
182	10.2.173.168/29	10.2.173.169 – 10.2.173.174	10.2.173.175
183	10.2.173.176/29	10.2.173.177 – 10.2.173.182	10.2.173.183
184	10.2.173.184/29	10.2.173.185 – 10.2.173.190	10.2.173.191
185	10.2.173.192/29	10.2.173.193 – 10.2.173.198	10.2.173.199
186	10.2.173.200/29	10.2.173.201 – 10.2.173.206	10.2.173.207
187	10.2.173.208/29	10.2.173.209 – 10.2.173.214	10.2.173.215
188	10.2.173.216/29	10.2.173.217 – 10.2.173.222	10.2.173.223
189	10.2.173.224/29	10.2.173.225 – 10.2.173.230	10.2.173.231
190	10.2.173.232/29	10.2.173.233 – 10.2.173.238	10.2.173.239
191	10.2.173.240/29	10.2.173.241 – 10.2.173.246	10.2.173.247
192	10.2.173.248/29	10.2.173.249 – 10.2.173.254	10.2.173.255
193	10.2.174.0/29	10.2.174.1 – 10.2.174.6	10.2.174.7
194	10.2.174.8/29	10.2.174.9 – 10.2.174.14	10.2.174.15
195	10.2.174.16/29	10.2.174.17 – 10.2.174.22	10.2.174.23
196	10.2.174.24/29	10.2.174.25 – 10.2.174.30	10.2.174.31
197	10.2.174.32/29	10.2.174.33 – 10.2.174.38	10.2.174.39
198	10.2.174.40/29	10.2.174.41 – 10.2.174.46	10.2.174.47
199	10.2.174.48/29	10.2.174.49 – 10.2.174.54	10.2.174.55
200	10.2.174.56/29	10.2.174.57 – 10.2.174.62	10.2.174.63
201	10.2.174.64/29	10.2.174.65 – 10.2.174.70	10.2.174.71
202	10.2.174.72/29	10.2.174.73 – 10.2.174.78	10.2.174.79
203	10.2.174.80/29	10.2.174.81 – 10.2.174.86	10.2.174.87
204	10.2.174.88/29	10.2.174.89 – 10.2.174.94	10.2.174.95
205	10.2.174.96/29	10.2.174.97 – 10.2.174.102	10.2.174.103
206	10.2.174.104/29	10.2.174.105 – 10.2.174.110	10.2.174.111
207	10.2.174.112/29	10.2.174.113 – 10.2.174.118	10.2.174.119
208	10.2.174.120/29	10.2.174.121 – 10.2.174.126	10.2.174.127
209	10.2.174.128/29	10.2.174.129 – 10.2.174.134	10.2.174.135
210	10.2.174.136/29	10.2.174.137 – 10.2.174.142	10.2.174.143
211	10.2.174.144/29	10.2.174.145 – 10.2.174.150	10.2.174.151
212	10.2.174.152/29	10.2.174.153 – 10.2.174.158	10.2.174.159
213	10.2.174.160/29	10.2.174.161 – 10.2.174.166	10.2.174.167
214	10.2.174.168/29	10.2.174.169 – 10.2.174.174	10.2.174.175
215	10.2.174.176/29	10.2.174.177 – 10.2.174.182	10.2.174.183
216	10.2.174.184/29	10.2.174.185 – 10.2.174.190	10.2.174.191
217	10.2.174.192/29	10.2.174.193 – 10.2.174.198	10.2.174.199
218	10.2.174.200/29	10.2.174.201 – 10.2.174.206	10.2.174.207
219	10.2.174.208/29	10.2.174.209 – 10.2.174.214	10.2.174.215
220	10.2.174.216/29	10.2.174.217 – 10.2.174.222	10.2.174.223
221	10.2.174.224/29	10.2.174.225 – 10.2.174.230	10.2.174.231
222	10.2.174.232/29	10.2.174.233 – 10.2.174.238	10.2.174.239
223	10.2.174.240/29	10.2.174.241 – 10.2.174.246	10.2.174.247
224	10.2.174.248/29	10.2.174.249 – 10.2.174.254	10.2.174.255
225	10.2.175.0/29	10.2.175.1 – 10.2.175.6	10.2.175.7
226	10.2.175.8/29	10.2.175.9 – 10.2.175.14	10.2.175.15
227	10.2.175.16/29	10.2.175.17 – 10.2.175.22	10.2.175.23
228	10.2.175.24/29	10.2.175.25 – 10.2.175.30	10.2.175.31
229	10.2.175.32/29	10.2.175.33 – 10.2.175.38	10.2.175.39
230	10.2.175.40/29	10.2.175.41 – 10.2.175.46	10.2.175.47
231	10.2.175.48/29	10.2.175.49 – 10.2.175.54	10.2.175.55
232	10.2.175.56/29	10.2.175.57 – 10.2.175.62	10.2.175.63
233	10.2.175.64/29	10.2.175.65 – 10.2.175.70	10.2.175.71
234	10.2.175.72/29	10.2.175.73 – 10.2.175.78	10.2.175.79
235	10.2.175.80/29	10.2.175.81 – 10.2.175.86	10.2.175.87
236	10.2.175.88/29	10.2.175.89 – 10.2.175.94	10.2.175.95
237	10.2.175.96/29	10.2.175.97 – 10.2.175.102	10.2.175.103
238	10.2.175.104/29	10.2.175.105 – 10.2.175.110	10.2.175.111
239	10.2.175.112/29	10.2.175.113 – 10.2.175.118	10.2.175.119
240	10.2.175.120/29	10.2.175.121 – 10.2.175.126	10.2.175.127
241	10.2.175.128/29	10.2.175.129 – 10.2.175.134	10.2.175.135
242	10.2.175.136/29	10.2.175.137 – 10.2.175.142	10.2.175.143
243	10.2.175.144/29	10.2.175.145 – 10.2.175.150	10.2.175.151
244	10.2.175.152/29	10.2.175.153 – 10.2.175.158	10.2.175.159
245	10.2.175.160/29	10.2.175.161 – 10.2.175.166	10.2.175.167
246	10.2.175.168/29	10.2.175.169 – 10.2.175.174	10.2.175.175
247	10.2.175.176/29	10.2.175.177 – 10.2.175.182	10.2.175.183
248	10.2.175.184/29	10.2.175.185 – 10.2.175.190	10.2.175.191
249	10.2.175.192/29	10.2.175.193 – 10.2.175.198	10.2.175.199
250	10.2.175.200/29	10.2.175.201 – 10.2.175.206	10.2.175.207
251	10.2.175.208/29	10.2.175.209 – 10.2.175.214	10.2.175.215
252	10.2.175.216/29	10.2.175.217 – 10.2.175.222	10.2.175.223
253	10.2.175.224/29	10.2.175.225 – 10.2.175.230	10.2.175.231
254	10.2.175.232/29	10.2.175.233 – 10.2.175.238	10.2.175.239
255	10.2.175.240/29	10.2.175.241 – 10.2.175.246	10.2.175.247
256	10.2.175.248/29	10.2.175.249 – 10.2.175.254	10.2.175.255

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 →