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)10.3.24.0/21

network10.3.24.0/21

broadcast10.3.31.255

first host10.3.24.1

last host10.3.31.254

subnet mask255.255.248.0

wildcard0.0.7.255

addresses2,048

usable hosts2,046

classA

ipcalc 10.3.24.0/21

address00001010.00000011.00011000.00000000

subnet mask11111111.11111111.11111000.00000000

network00001010.00000011.00011000.00000000

broadcast00001010.00000011.00011111.11111111

green = network part, grey = host part

hex0x0a031800

decimal167974912

reverse dns0.24.3.10.in-addr.arpa

ipv4-mapped::ffff:a03:1800

/21 split into /29 · 256 subnets

close ×

#	network	host range	broadcast
1	10.3.24.0/29	10.3.24.1 – 10.3.24.6	10.3.24.7
2	10.3.24.8/29	10.3.24.9 – 10.3.24.14	10.3.24.15
3	10.3.24.16/29	10.3.24.17 – 10.3.24.22	10.3.24.23
4	10.3.24.24/29	10.3.24.25 – 10.3.24.30	10.3.24.31
5	10.3.24.32/29	10.3.24.33 – 10.3.24.38	10.3.24.39
6	10.3.24.40/29	10.3.24.41 – 10.3.24.46	10.3.24.47
7	10.3.24.48/29	10.3.24.49 – 10.3.24.54	10.3.24.55
8	10.3.24.56/29	10.3.24.57 – 10.3.24.62	10.3.24.63
9	10.3.24.64/29	10.3.24.65 – 10.3.24.70	10.3.24.71
10	10.3.24.72/29	10.3.24.73 – 10.3.24.78	10.3.24.79
11	10.3.24.80/29	10.3.24.81 – 10.3.24.86	10.3.24.87
12	10.3.24.88/29	10.3.24.89 – 10.3.24.94	10.3.24.95
13	10.3.24.96/29	10.3.24.97 – 10.3.24.102	10.3.24.103
14	10.3.24.104/29	10.3.24.105 – 10.3.24.110	10.3.24.111
15	10.3.24.112/29	10.3.24.113 – 10.3.24.118	10.3.24.119
16	10.3.24.120/29	10.3.24.121 – 10.3.24.126	10.3.24.127
17	10.3.24.128/29	10.3.24.129 – 10.3.24.134	10.3.24.135
18	10.3.24.136/29	10.3.24.137 – 10.3.24.142	10.3.24.143
19	10.3.24.144/29	10.3.24.145 – 10.3.24.150	10.3.24.151
20	10.3.24.152/29	10.3.24.153 – 10.3.24.158	10.3.24.159
21	10.3.24.160/29	10.3.24.161 – 10.3.24.166	10.3.24.167
22	10.3.24.168/29	10.3.24.169 – 10.3.24.174	10.3.24.175
23	10.3.24.176/29	10.3.24.177 – 10.3.24.182	10.3.24.183
24	10.3.24.184/29	10.3.24.185 – 10.3.24.190	10.3.24.191
25	10.3.24.192/29	10.3.24.193 – 10.3.24.198	10.3.24.199
26	10.3.24.200/29	10.3.24.201 – 10.3.24.206	10.3.24.207
27	10.3.24.208/29	10.3.24.209 – 10.3.24.214	10.3.24.215
28	10.3.24.216/29	10.3.24.217 – 10.3.24.222	10.3.24.223
29	10.3.24.224/29	10.3.24.225 – 10.3.24.230	10.3.24.231
30	10.3.24.232/29	10.3.24.233 – 10.3.24.238	10.3.24.239
31	10.3.24.240/29	10.3.24.241 – 10.3.24.246	10.3.24.247
32	10.3.24.248/29	10.3.24.249 – 10.3.24.254	10.3.24.255
33	10.3.25.0/29	10.3.25.1 – 10.3.25.6	10.3.25.7
34	10.3.25.8/29	10.3.25.9 – 10.3.25.14	10.3.25.15
35	10.3.25.16/29	10.3.25.17 – 10.3.25.22	10.3.25.23
36	10.3.25.24/29	10.3.25.25 – 10.3.25.30	10.3.25.31
37	10.3.25.32/29	10.3.25.33 – 10.3.25.38	10.3.25.39
38	10.3.25.40/29	10.3.25.41 – 10.3.25.46	10.3.25.47
39	10.3.25.48/29	10.3.25.49 – 10.3.25.54	10.3.25.55
40	10.3.25.56/29	10.3.25.57 – 10.3.25.62	10.3.25.63
41	10.3.25.64/29	10.3.25.65 – 10.3.25.70	10.3.25.71
42	10.3.25.72/29	10.3.25.73 – 10.3.25.78	10.3.25.79
43	10.3.25.80/29	10.3.25.81 – 10.3.25.86	10.3.25.87
44	10.3.25.88/29	10.3.25.89 – 10.3.25.94	10.3.25.95
45	10.3.25.96/29	10.3.25.97 – 10.3.25.102	10.3.25.103
46	10.3.25.104/29	10.3.25.105 – 10.3.25.110	10.3.25.111
47	10.3.25.112/29	10.3.25.113 – 10.3.25.118	10.3.25.119
48	10.3.25.120/29	10.3.25.121 – 10.3.25.126	10.3.25.127
49	10.3.25.128/29	10.3.25.129 – 10.3.25.134	10.3.25.135
50	10.3.25.136/29	10.3.25.137 – 10.3.25.142	10.3.25.143
51	10.3.25.144/29	10.3.25.145 – 10.3.25.150	10.3.25.151
52	10.3.25.152/29	10.3.25.153 – 10.3.25.158	10.3.25.159
53	10.3.25.160/29	10.3.25.161 – 10.3.25.166	10.3.25.167
54	10.3.25.168/29	10.3.25.169 – 10.3.25.174	10.3.25.175
55	10.3.25.176/29	10.3.25.177 – 10.3.25.182	10.3.25.183
56	10.3.25.184/29	10.3.25.185 – 10.3.25.190	10.3.25.191
57	10.3.25.192/29	10.3.25.193 – 10.3.25.198	10.3.25.199
58	10.3.25.200/29	10.3.25.201 – 10.3.25.206	10.3.25.207
59	10.3.25.208/29	10.3.25.209 – 10.3.25.214	10.3.25.215
60	10.3.25.216/29	10.3.25.217 – 10.3.25.222	10.3.25.223
61	10.3.25.224/29	10.3.25.225 – 10.3.25.230	10.3.25.231
62	10.3.25.232/29	10.3.25.233 – 10.3.25.238	10.3.25.239
63	10.3.25.240/29	10.3.25.241 – 10.3.25.246	10.3.25.247
64	10.3.25.248/29	10.3.25.249 – 10.3.25.254	10.3.25.255
65	10.3.26.0/29	10.3.26.1 – 10.3.26.6	10.3.26.7
66	10.3.26.8/29	10.3.26.9 – 10.3.26.14	10.3.26.15
67	10.3.26.16/29	10.3.26.17 – 10.3.26.22	10.3.26.23
68	10.3.26.24/29	10.3.26.25 – 10.3.26.30	10.3.26.31
69	10.3.26.32/29	10.3.26.33 – 10.3.26.38	10.3.26.39
70	10.3.26.40/29	10.3.26.41 – 10.3.26.46	10.3.26.47
71	10.3.26.48/29	10.3.26.49 – 10.3.26.54	10.3.26.55
72	10.3.26.56/29	10.3.26.57 – 10.3.26.62	10.3.26.63
73	10.3.26.64/29	10.3.26.65 – 10.3.26.70	10.3.26.71
74	10.3.26.72/29	10.3.26.73 – 10.3.26.78	10.3.26.79
75	10.3.26.80/29	10.3.26.81 – 10.3.26.86	10.3.26.87
76	10.3.26.88/29	10.3.26.89 – 10.3.26.94	10.3.26.95
77	10.3.26.96/29	10.3.26.97 – 10.3.26.102	10.3.26.103
78	10.3.26.104/29	10.3.26.105 – 10.3.26.110	10.3.26.111
79	10.3.26.112/29	10.3.26.113 – 10.3.26.118	10.3.26.119
80	10.3.26.120/29	10.3.26.121 – 10.3.26.126	10.3.26.127
81	10.3.26.128/29	10.3.26.129 – 10.3.26.134	10.3.26.135
82	10.3.26.136/29	10.3.26.137 – 10.3.26.142	10.3.26.143
83	10.3.26.144/29	10.3.26.145 – 10.3.26.150	10.3.26.151
84	10.3.26.152/29	10.3.26.153 – 10.3.26.158	10.3.26.159
85	10.3.26.160/29	10.3.26.161 – 10.3.26.166	10.3.26.167
86	10.3.26.168/29	10.3.26.169 – 10.3.26.174	10.3.26.175
87	10.3.26.176/29	10.3.26.177 – 10.3.26.182	10.3.26.183
88	10.3.26.184/29	10.3.26.185 – 10.3.26.190	10.3.26.191
89	10.3.26.192/29	10.3.26.193 – 10.3.26.198	10.3.26.199
90	10.3.26.200/29	10.3.26.201 – 10.3.26.206	10.3.26.207
91	10.3.26.208/29	10.3.26.209 – 10.3.26.214	10.3.26.215
92	10.3.26.216/29	10.3.26.217 – 10.3.26.222	10.3.26.223
93	10.3.26.224/29	10.3.26.225 – 10.3.26.230	10.3.26.231
94	10.3.26.232/29	10.3.26.233 – 10.3.26.238	10.3.26.239
95	10.3.26.240/29	10.3.26.241 – 10.3.26.246	10.3.26.247
96	10.3.26.248/29	10.3.26.249 – 10.3.26.254	10.3.26.255
97	10.3.27.0/29	10.3.27.1 – 10.3.27.6	10.3.27.7
98	10.3.27.8/29	10.3.27.9 – 10.3.27.14	10.3.27.15
99	10.3.27.16/29	10.3.27.17 – 10.3.27.22	10.3.27.23
100	10.3.27.24/29	10.3.27.25 – 10.3.27.30	10.3.27.31
101	10.3.27.32/29	10.3.27.33 – 10.3.27.38	10.3.27.39
102	10.3.27.40/29	10.3.27.41 – 10.3.27.46	10.3.27.47
103	10.3.27.48/29	10.3.27.49 – 10.3.27.54	10.3.27.55
104	10.3.27.56/29	10.3.27.57 – 10.3.27.62	10.3.27.63
105	10.3.27.64/29	10.3.27.65 – 10.3.27.70	10.3.27.71
106	10.3.27.72/29	10.3.27.73 – 10.3.27.78	10.3.27.79
107	10.3.27.80/29	10.3.27.81 – 10.3.27.86	10.3.27.87
108	10.3.27.88/29	10.3.27.89 – 10.3.27.94	10.3.27.95
109	10.3.27.96/29	10.3.27.97 – 10.3.27.102	10.3.27.103
110	10.3.27.104/29	10.3.27.105 – 10.3.27.110	10.3.27.111
111	10.3.27.112/29	10.3.27.113 – 10.3.27.118	10.3.27.119
112	10.3.27.120/29	10.3.27.121 – 10.3.27.126	10.3.27.127
113	10.3.27.128/29	10.3.27.129 – 10.3.27.134	10.3.27.135
114	10.3.27.136/29	10.3.27.137 – 10.3.27.142	10.3.27.143
115	10.3.27.144/29	10.3.27.145 – 10.3.27.150	10.3.27.151
116	10.3.27.152/29	10.3.27.153 – 10.3.27.158	10.3.27.159
117	10.3.27.160/29	10.3.27.161 – 10.3.27.166	10.3.27.167
118	10.3.27.168/29	10.3.27.169 – 10.3.27.174	10.3.27.175
119	10.3.27.176/29	10.3.27.177 – 10.3.27.182	10.3.27.183
120	10.3.27.184/29	10.3.27.185 – 10.3.27.190	10.3.27.191
121	10.3.27.192/29	10.3.27.193 – 10.3.27.198	10.3.27.199
122	10.3.27.200/29	10.3.27.201 – 10.3.27.206	10.3.27.207
123	10.3.27.208/29	10.3.27.209 – 10.3.27.214	10.3.27.215
124	10.3.27.216/29	10.3.27.217 – 10.3.27.222	10.3.27.223
125	10.3.27.224/29	10.3.27.225 – 10.3.27.230	10.3.27.231
126	10.3.27.232/29	10.3.27.233 – 10.3.27.238	10.3.27.239
127	10.3.27.240/29	10.3.27.241 – 10.3.27.246	10.3.27.247
128	10.3.27.248/29	10.3.27.249 – 10.3.27.254	10.3.27.255
129	10.3.28.0/29	10.3.28.1 – 10.3.28.6	10.3.28.7
130	10.3.28.8/29	10.3.28.9 – 10.3.28.14	10.3.28.15
131	10.3.28.16/29	10.3.28.17 – 10.3.28.22	10.3.28.23
132	10.3.28.24/29	10.3.28.25 – 10.3.28.30	10.3.28.31
133	10.3.28.32/29	10.3.28.33 – 10.3.28.38	10.3.28.39
134	10.3.28.40/29	10.3.28.41 – 10.3.28.46	10.3.28.47
135	10.3.28.48/29	10.3.28.49 – 10.3.28.54	10.3.28.55
136	10.3.28.56/29	10.3.28.57 – 10.3.28.62	10.3.28.63
137	10.3.28.64/29	10.3.28.65 – 10.3.28.70	10.3.28.71
138	10.3.28.72/29	10.3.28.73 – 10.3.28.78	10.3.28.79
139	10.3.28.80/29	10.3.28.81 – 10.3.28.86	10.3.28.87
140	10.3.28.88/29	10.3.28.89 – 10.3.28.94	10.3.28.95
141	10.3.28.96/29	10.3.28.97 – 10.3.28.102	10.3.28.103
142	10.3.28.104/29	10.3.28.105 – 10.3.28.110	10.3.28.111
143	10.3.28.112/29	10.3.28.113 – 10.3.28.118	10.3.28.119
144	10.3.28.120/29	10.3.28.121 – 10.3.28.126	10.3.28.127
145	10.3.28.128/29	10.3.28.129 – 10.3.28.134	10.3.28.135
146	10.3.28.136/29	10.3.28.137 – 10.3.28.142	10.3.28.143
147	10.3.28.144/29	10.3.28.145 – 10.3.28.150	10.3.28.151
148	10.3.28.152/29	10.3.28.153 – 10.3.28.158	10.3.28.159
149	10.3.28.160/29	10.3.28.161 – 10.3.28.166	10.3.28.167
150	10.3.28.168/29	10.3.28.169 – 10.3.28.174	10.3.28.175
151	10.3.28.176/29	10.3.28.177 – 10.3.28.182	10.3.28.183
152	10.3.28.184/29	10.3.28.185 – 10.3.28.190	10.3.28.191
153	10.3.28.192/29	10.3.28.193 – 10.3.28.198	10.3.28.199
154	10.3.28.200/29	10.3.28.201 – 10.3.28.206	10.3.28.207
155	10.3.28.208/29	10.3.28.209 – 10.3.28.214	10.3.28.215
156	10.3.28.216/29	10.3.28.217 – 10.3.28.222	10.3.28.223
157	10.3.28.224/29	10.3.28.225 – 10.3.28.230	10.3.28.231
158	10.3.28.232/29	10.3.28.233 – 10.3.28.238	10.3.28.239
159	10.3.28.240/29	10.3.28.241 – 10.3.28.246	10.3.28.247
160	10.3.28.248/29	10.3.28.249 – 10.3.28.254	10.3.28.255
161	10.3.29.0/29	10.3.29.1 – 10.3.29.6	10.3.29.7
162	10.3.29.8/29	10.3.29.9 – 10.3.29.14	10.3.29.15
163	10.3.29.16/29	10.3.29.17 – 10.3.29.22	10.3.29.23
164	10.3.29.24/29	10.3.29.25 – 10.3.29.30	10.3.29.31
165	10.3.29.32/29	10.3.29.33 – 10.3.29.38	10.3.29.39
166	10.3.29.40/29	10.3.29.41 – 10.3.29.46	10.3.29.47
167	10.3.29.48/29	10.3.29.49 – 10.3.29.54	10.3.29.55
168	10.3.29.56/29	10.3.29.57 – 10.3.29.62	10.3.29.63
169	10.3.29.64/29	10.3.29.65 – 10.3.29.70	10.3.29.71
170	10.3.29.72/29	10.3.29.73 – 10.3.29.78	10.3.29.79
171	10.3.29.80/29	10.3.29.81 – 10.3.29.86	10.3.29.87
172	10.3.29.88/29	10.3.29.89 – 10.3.29.94	10.3.29.95
173	10.3.29.96/29	10.3.29.97 – 10.3.29.102	10.3.29.103
174	10.3.29.104/29	10.3.29.105 – 10.3.29.110	10.3.29.111
175	10.3.29.112/29	10.3.29.113 – 10.3.29.118	10.3.29.119
176	10.3.29.120/29	10.3.29.121 – 10.3.29.126	10.3.29.127
177	10.3.29.128/29	10.3.29.129 – 10.3.29.134	10.3.29.135
178	10.3.29.136/29	10.3.29.137 – 10.3.29.142	10.3.29.143
179	10.3.29.144/29	10.3.29.145 – 10.3.29.150	10.3.29.151
180	10.3.29.152/29	10.3.29.153 – 10.3.29.158	10.3.29.159
181	10.3.29.160/29	10.3.29.161 – 10.3.29.166	10.3.29.167
182	10.3.29.168/29	10.3.29.169 – 10.3.29.174	10.3.29.175
183	10.3.29.176/29	10.3.29.177 – 10.3.29.182	10.3.29.183
184	10.3.29.184/29	10.3.29.185 – 10.3.29.190	10.3.29.191
185	10.3.29.192/29	10.3.29.193 – 10.3.29.198	10.3.29.199
186	10.3.29.200/29	10.3.29.201 – 10.3.29.206	10.3.29.207
187	10.3.29.208/29	10.3.29.209 – 10.3.29.214	10.3.29.215
188	10.3.29.216/29	10.3.29.217 – 10.3.29.222	10.3.29.223
189	10.3.29.224/29	10.3.29.225 – 10.3.29.230	10.3.29.231
190	10.3.29.232/29	10.3.29.233 – 10.3.29.238	10.3.29.239
191	10.3.29.240/29	10.3.29.241 – 10.3.29.246	10.3.29.247
192	10.3.29.248/29	10.3.29.249 – 10.3.29.254	10.3.29.255
193	10.3.30.0/29	10.3.30.1 – 10.3.30.6	10.3.30.7
194	10.3.30.8/29	10.3.30.9 – 10.3.30.14	10.3.30.15
195	10.3.30.16/29	10.3.30.17 – 10.3.30.22	10.3.30.23
196	10.3.30.24/29	10.3.30.25 – 10.3.30.30	10.3.30.31
197	10.3.30.32/29	10.3.30.33 – 10.3.30.38	10.3.30.39
198	10.3.30.40/29	10.3.30.41 – 10.3.30.46	10.3.30.47
199	10.3.30.48/29	10.3.30.49 – 10.3.30.54	10.3.30.55
200	10.3.30.56/29	10.3.30.57 – 10.3.30.62	10.3.30.63
201	10.3.30.64/29	10.3.30.65 – 10.3.30.70	10.3.30.71
202	10.3.30.72/29	10.3.30.73 – 10.3.30.78	10.3.30.79
203	10.3.30.80/29	10.3.30.81 – 10.3.30.86	10.3.30.87
204	10.3.30.88/29	10.3.30.89 – 10.3.30.94	10.3.30.95
205	10.3.30.96/29	10.3.30.97 – 10.3.30.102	10.3.30.103
206	10.3.30.104/29	10.3.30.105 – 10.3.30.110	10.3.30.111
207	10.3.30.112/29	10.3.30.113 – 10.3.30.118	10.3.30.119
208	10.3.30.120/29	10.3.30.121 – 10.3.30.126	10.3.30.127
209	10.3.30.128/29	10.3.30.129 – 10.3.30.134	10.3.30.135
210	10.3.30.136/29	10.3.30.137 – 10.3.30.142	10.3.30.143
211	10.3.30.144/29	10.3.30.145 – 10.3.30.150	10.3.30.151
212	10.3.30.152/29	10.3.30.153 – 10.3.30.158	10.3.30.159
213	10.3.30.160/29	10.3.30.161 – 10.3.30.166	10.3.30.167
214	10.3.30.168/29	10.3.30.169 – 10.3.30.174	10.3.30.175
215	10.3.30.176/29	10.3.30.177 – 10.3.30.182	10.3.30.183
216	10.3.30.184/29	10.3.30.185 – 10.3.30.190	10.3.30.191
217	10.3.30.192/29	10.3.30.193 – 10.3.30.198	10.3.30.199
218	10.3.30.200/29	10.3.30.201 – 10.3.30.206	10.3.30.207
219	10.3.30.208/29	10.3.30.209 – 10.3.30.214	10.3.30.215
220	10.3.30.216/29	10.3.30.217 – 10.3.30.222	10.3.30.223
221	10.3.30.224/29	10.3.30.225 – 10.3.30.230	10.3.30.231
222	10.3.30.232/29	10.3.30.233 – 10.3.30.238	10.3.30.239
223	10.3.30.240/29	10.3.30.241 – 10.3.30.246	10.3.30.247
224	10.3.30.248/29	10.3.30.249 – 10.3.30.254	10.3.30.255
225	10.3.31.0/29	10.3.31.1 – 10.3.31.6	10.3.31.7
226	10.3.31.8/29	10.3.31.9 – 10.3.31.14	10.3.31.15
227	10.3.31.16/29	10.3.31.17 – 10.3.31.22	10.3.31.23
228	10.3.31.24/29	10.3.31.25 – 10.3.31.30	10.3.31.31
229	10.3.31.32/29	10.3.31.33 – 10.3.31.38	10.3.31.39
230	10.3.31.40/29	10.3.31.41 – 10.3.31.46	10.3.31.47
231	10.3.31.48/29	10.3.31.49 – 10.3.31.54	10.3.31.55
232	10.3.31.56/29	10.3.31.57 – 10.3.31.62	10.3.31.63
233	10.3.31.64/29	10.3.31.65 – 10.3.31.70	10.3.31.71
234	10.3.31.72/29	10.3.31.73 – 10.3.31.78	10.3.31.79
235	10.3.31.80/29	10.3.31.81 – 10.3.31.86	10.3.31.87
236	10.3.31.88/29	10.3.31.89 – 10.3.31.94	10.3.31.95
237	10.3.31.96/29	10.3.31.97 – 10.3.31.102	10.3.31.103
238	10.3.31.104/29	10.3.31.105 – 10.3.31.110	10.3.31.111
239	10.3.31.112/29	10.3.31.113 – 10.3.31.118	10.3.31.119
240	10.3.31.120/29	10.3.31.121 – 10.3.31.126	10.3.31.127
241	10.3.31.128/29	10.3.31.129 – 10.3.31.134	10.3.31.135
242	10.3.31.136/29	10.3.31.137 – 10.3.31.142	10.3.31.143
243	10.3.31.144/29	10.3.31.145 – 10.3.31.150	10.3.31.151
244	10.3.31.152/29	10.3.31.153 – 10.3.31.158	10.3.31.159
245	10.3.31.160/29	10.3.31.161 – 10.3.31.166	10.3.31.167
246	10.3.31.168/29	10.3.31.169 – 10.3.31.174	10.3.31.175
247	10.3.31.176/29	10.3.31.177 – 10.3.31.182	10.3.31.183
248	10.3.31.184/29	10.3.31.185 – 10.3.31.190	10.3.31.191
249	10.3.31.192/29	10.3.31.193 – 10.3.31.198	10.3.31.199
250	10.3.31.200/29	10.3.31.201 – 10.3.31.206	10.3.31.207
251	10.3.31.208/29	10.3.31.209 – 10.3.31.214	10.3.31.215
252	10.3.31.216/29	10.3.31.217 – 10.3.31.222	10.3.31.223
253	10.3.31.224/29	10.3.31.225 – 10.3.31.230	10.3.31.231
254	10.3.31.232/29	10.3.31.233 – 10.3.31.238	10.3.31.239
255	10.3.31.240/29	10.3.31.241 – 10.3.31.246	10.3.31.247
256	10.3.31.248/29	10.3.31.249 – 10.3.31.254	10.3.31.255

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 →