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)10.2.0.0/21

network10.2.0.0/21

broadcast10.2.7.255

first host10.2.0.1

last host10.2.7.254

subnet mask255.255.248.0

wildcard0.0.7.255

addresses2,048

usable hosts2,046

classA

ipcalc 10.2.0.0/21

address00001010.00000010.00000000.00000000

subnet mask11111111.11111111.11111000.00000000

network00001010.00000010.00000000.00000000

broadcast00001010.00000010.00000111.11111111

green = network part, grey = host part

hex0x0a020000

decimal167903232

reverse dns0.0.2.10.in-addr.arpa

ipv4-mapped::ffff:a02:0

/21 split into /30 · 512 subnets

close ×

#	network	host range	broadcast
1	10.2.0.0/30	10.2.0.1 – 10.2.0.2	10.2.0.3
2	10.2.0.4/30	10.2.0.5 – 10.2.0.6	10.2.0.7
3	10.2.0.8/30	10.2.0.9 – 10.2.0.10	10.2.0.11
4	10.2.0.12/30	10.2.0.13 – 10.2.0.14	10.2.0.15
5	10.2.0.16/30	10.2.0.17 – 10.2.0.18	10.2.0.19
6	10.2.0.20/30	10.2.0.21 – 10.2.0.22	10.2.0.23
7	10.2.0.24/30	10.2.0.25 – 10.2.0.26	10.2.0.27
8	10.2.0.28/30	10.2.0.29 – 10.2.0.30	10.2.0.31
9	10.2.0.32/30	10.2.0.33 – 10.2.0.34	10.2.0.35
10	10.2.0.36/30	10.2.0.37 – 10.2.0.38	10.2.0.39
11	10.2.0.40/30	10.2.0.41 – 10.2.0.42	10.2.0.43
12	10.2.0.44/30	10.2.0.45 – 10.2.0.46	10.2.0.47
13	10.2.0.48/30	10.2.0.49 – 10.2.0.50	10.2.0.51
14	10.2.0.52/30	10.2.0.53 – 10.2.0.54	10.2.0.55
15	10.2.0.56/30	10.2.0.57 – 10.2.0.58	10.2.0.59
16	10.2.0.60/30	10.2.0.61 – 10.2.0.62	10.2.0.63
17	10.2.0.64/30	10.2.0.65 – 10.2.0.66	10.2.0.67
18	10.2.0.68/30	10.2.0.69 – 10.2.0.70	10.2.0.71
19	10.2.0.72/30	10.2.0.73 – 10.2.0.74	10.2.0.75
20	10.2.0.76/30	10.2.0.77 – 10.2.0.78	10.2.0.79
21	10.2.0.80/30	10.2.0.81 – 10.2.0.82	10.2.0.83
22	10.2.0.84/30	10.2.0.85 – 10.2.0.86	10.2.0.87
23	10.2.0.88/30	10.2.0.89 – 10.2.0.90	10.2.0.91
24	10.2.0.92/30	10.2.0.93 – 10.2.0.94	10.2.0.95
25	10.2.0.96/30	10.2.0.97 – 10.2.0.98	10.2.0.99
26	10.2.0.100/30	10.2.0.101 – 10.2.0.102	10.2.0.103
27	10.2.0.104/30	10.2.0.105 – 10.2.0.106	10.2.0.107
28	10.2.0.108/30	10.2.0.109 – 10.2.0.110	10.2.0.111
29	10.2.0.112/30	10.2.0.113 – 10.2.0.114	10.2.0.115
30	10.2.0.116/30	10.2.0.117 – 10.2.0.118	10.2.0.119
31	10.2.0.120/30	10.2.0.121 – 10.2.0.122	10.2.0.123
32	10.2.0.124/30	10.2.0.125 – 10.2.0.126	10.2.0.127
33	10.2.0.128/30	10.2.0.129 – 10.2.0.130	10.2.0.131
34	10.2.0.132/30	10.2.0.133 – 10.2.0.134	10.2.0.135
35	10.2.0.136/30	10.2.0.137 – 10.2.0.138	10.2.0.139
36	10.2.0.140/30	10.2.0.141 – 10.2.0.142	10.2.0.143
37	10.2.0.144/30	10.2.0.145 – 10.2.0.146	10.2.0.147
38	10.2.0.148/30	10.2.0.149 – 10.2.0.150	10.2.0.151
39	10.2.0.152/30	10.2.0.153 – 10.2.0.154	10.2.0.155
40	10.2.0.156/30	10.2.0.157 – 10.2.0.158	10.2.0.159
41	10.2.0.160/30	10.2.0.161 – 10.2.0.162	10.2.0.163
42	10.2.0.164/30	10.2.0.165 – 10.2.0.166	10.2.0.167
43	10.2.0.168/30	10.2.0.169 – 10.2.0.170	10.2.0.171
44	10.2.0.172/30	10.2.0.173 – 10.2.0.174	10.2.0.175
45	10.2.0.176/30	10.2.0.177 – 10.2.0.178	10.2.0.179
46	10.2.0.180/30	10.2.0.181 – 10.2.0.182	10.2.0.183
47	10.2.0.184/30	10.2.0.185 – 10.2.0.186	10.2.0.187
48	10.2.0.188/30	10.2.0.189 – 10.2.0.190	10.2.0.191
49	10.2.0.192/30	10.2.0.193 – 10.2.0.194	10.2.0.195
50	10.2.0.196/30	10.2.0.197 – 10.2.0.198	10.2.0.199
51	10.2.0.200/30	10.2.0.201 – 10.2.0.202	10.2.0.203
52	10.2.0.204/30	10.2.0.205 – 10.2.0.206	10.2.0.207
53	10.2.0.208/30	10.2.0.209 – 10.2.0.210	10.2.0.211
54	10.2.0.212/30	10.2.0.213 – 10.2.0.214	10.2.0.215
55	10.2.0.216/30	10.2.0.217 – 10.2.0.218	10.2.0.219
56	10.2.0.220/30	10.2.0.221 – 10.2.0.222	10.2.0.223
57	10.2.0.224/30	10.2.0.225 – 10.2.0.226	10.2.0.227
58	10.2.0.228/30	10.2.0.229 – 10.2.0.230	10.2.0.231
59	10.2.0.232/30	10.2.0.233 – 10.2.0.234	10.2.0.235
60	10.2.0.236/30	10.2.0.237 – 10.2.0.238	10.2.0.239
61	10.2.0.240/30	10.2.0.241 – 10.2.0.242	10.2.0.243
62	10.2.0.244/30	10.2.0.245 – 10.2.0.246	10.2.0.247
63	10.2.0.248/30	10.2.0.249 – 10.2.0.250	10.2.0.251
64	10.2.0.252/30	10.2.0.253 – 10.2.0.254	10.2.0.255
65	10.2.1.0/30	10.2.1.1 – 10.2.1.2	10.2.1.3
66	10.2.1.4/30	10.2.1.5 – 10.2.1.6	10.2.1.7
67	10.2.1.8/30	10.2.1.9 – 10.2.1.10	10.2.1.11
68	10.2.1.12/30	10.2.1.13 – 10.2.1.14	10.2.1.15
69	10.2.1.16/30	10.2.1.17 – 10.2.1.18	10.2.1.19
70	10.2.1.20/30	10.2.1.21 – 10.2.1.22	10.2.1.23
71	10.2.1.24/30	10.2.1.25 – 10.2.1.26	10.2.1.27
72	10.2.1.28/30	10.2.1.29 – 10.2.1.30	10.2.1.31
73	10.2.1.32/30	10.2.1.33 – 10.2.1.34	10.2.1.35
74	10.2.1.36/30	10.2.1.37 – 10.2.1.38	10.2.1.39
75	10.2.1.40/30	10.2.1.41 – 10.2.1.42	10.2.1.43
76	10.2.1.44/30	10.2.1.45 – 10.2.1.46	10.2.1.47
77	10.2.1.48/30	10.2.1.49 – 10.2.1.50	10.2.1.51
78	10.2.1.52/30	10.2.1.53 – 10.2.1.54	10.2.1.55
79	10.2.1.56/30	10.2.1.57 – 10.2.1.58	10.2.1.59
80	10.2.1.60/30	10.2.1.61 – 10.2.1.62	10.2.1.63
81	10.2.1.64/30	10.2.1.65 – 10.2.1.66	10.2.1.67
82	10.2.1.68/30	10.2.1.69 – 10.2.1.70	10.2.1.71
83	10.2.1.72/30	10.2.1.73 – 10.2.1.74	10.2.1.75
84	10.2.1.76/30	10.2.1.77 – 10.2.1.78	10.2.1.79
85	10.2.1.80/30	10.2.1.81 – 10.2.1.82	10.2.1.83
86	10.2.1.84/30	10.2.1.85 – 10.2.1.86	10.2.1.87
87	10.2.1.88/30	10.2.1.89 – 10.2.1.90	10.2.1.91
88	10.2.1.92/30	10.2.1.93 – 10.2.1.94	10.2.1.95
89	10.2.1.96/30	10.2.1.97 – 10.2.1.98	10.2.1.99
90	10.2.1.100/30	10.2.1.101 – 10.2.1.102	10.2.1.103
91	10.2.1.104/30	10.2.1.105 – 10.2.1.106	10.2.1.107
92	10.2.1.108/30	10.2.1.109 – 10.2.1.110	10.2.1.111
93	10.2.1.112/30	10.2.1.113 – 10.2.1.114	10.2.1.115
94	10.2.1.116/30	10.2.1.117 – 10.2.1.118	10.2.1.119
95	10.2.1.120/30	10.2.1.121 – 10.2.1.122	10.2.1.123
96	10.2.1.124/30	10.2.1.125 – 10.2.1.126	10.2.1.127
97	10.2.1.128/30	10.2.1.129 – 10.2.1.130	10.2.1.131
98	10.2.1.132/30	10.2.1.133 – 10.2.1.134	10.2.1.135
99	10.2.1.136/30	10.2.1.137 – 10.2.1.138	10.2.1.139
100	10.2.1.140/30	10.2.1.141 – 10.2.1.142	10.2.1.143
101	10.2.1.144/30	10.2.1.145 – 10.2.1.146	10.2.1.147
102	10.2.1.148/30	10.2.1.149 – 10.2.1.150	10.2.1.151
103	10.2.1.152/30	10.2.1.153 – 10.2.1.154	10.2.1.155
104	10.2.1.156/30	10.2.1.157 – 10.2.1.158	10.2.1.159
105	10.2.1.160/30	10.2.1.161 – 10.2.1.162	10.2.1.163
106	10.2.1.164/30	10.2.1.165 – 10.2.1.166	10.2.1.167
107	10.2.1.168/30	10.2.1.169 – 10.2.1.170	10.2.1.171
108	10.2.1.172/30	10.2.1.173 – 10.2.1.174	10.2.1.175
109	10.2.1.176/30	10.2.1.177 – 10.2.1.178	10.2.1.179
110	10.2.1.180/30	10.2.1.181 – 10.2.1.182	10.2.1.183
111	10.2.1.184/30	10.2.1.185 – 10.2.1.186	10.2.1.187
112	10.2.1.188/30	10.2.1.189 – 10.2.1.190	10.2.1.191
113	10.2.1.192/30	10.2.1.193 – 10.2.1.194	10.2.1.195
114	10.2.1.196/30	10.2.1.197 – 10.2.1.198	10.2.1.199
115	10.2.1.200/30	10.2.1.201 – 10.2.1.202	10.2.1.203
116	10.2.1.204/30	10.2.1.205 – 10.2.1.206	10.2.1.207
117	10.2.1.208/30	10.2.1.209 – 10.2.1.210	10.2.1.211
118	10.2.1.212/30	10.2.1.213 – 10.2.1.214	10.2.1.215
119	10.2.1.216/30	10.2.1.217 – 10.2.1.218	10.2.1.219
120	10.2.1.220/30	10.2.1.221 – 10.2.1.222	10.2.1.223
121	10.2.1.224/30	10.2.1.225 – 10.2.1.226	10.2.1.227
122	10.2.1.228/30	10.2.1.229 – 10.2.1.230	10.2.1.231
123	10.2.1.232/30	10.2.1.233 – 10.2.1.234	10.2.1.235
124	10.2.1.236/30	10.2.1.237 – 10.2.1.238	10.2.1.239
125	10.2.1.240/30	10.2.1.241 – 10.2.1.242	10.2.1.243
126	10.2.1.244/30	10.2.1.245 – 10.2.1.246	10.2.1.247
127	10.2.1.248/30	10.2.1.249 – 10.2.1.250	10.2.1.251
128	10.2.1.252/30	10.2.1.253 – 10.2.1.254	10.2.1.255
129	10.2.2.0/30	10.2.2.1 – 10.2.2.2	10.2.2.3
130	10.2.2.4/30	10.2.2.5 – 10.2.2.6	10.2.2.7
131	10.2.2.8/30	10.2.2.9 – 10.2.2.10	10.2.2.11
132	10.2.2.12/30	10.2.2.13 – 10.2.2.14	10.2.2.15
133	10.2.2.16/30	10.2.2.17 – 10.2.2.18	10.2.2.19
134	10.2.2.20/30	10.2.2.21 – 10.2.2.22	10.2.2.23
135	10.2.2.24/30	10.2.2.25 – 10.2.2.26	10.2.2.27
136	10.2.2.28/30	10.2.2.29 – 10.2.2.30	10.2.2.31
137	10.2.2.32/30	10.2.2.33 – 10.2.2.34	10.2.2.35
138	10.2.2.36/30	10.2.2.37 – 10.2.2.38	10.2.2.39
139	10.2.2.40/30	10.2.2.41 – 10.2.2.42	10.2.2.43
140	10.2.2.44/30	10.2.2.45 – 10.2.2.46	10.2.2.47
141	10.2.2.48/30	10.2.2.49 – 10.2.2.50	10.2.2.51
142	10.2.2.52/30	10.2.2.53 – 10.2.2.54	10.2.2.55
143	10.2.2.56/30	10.2.2.57 – 10.2.2.58	10.2.2.59
144	10.2.2.60/30	10.2.2.61 – 10.2.2.62	10.2.2.63
145	10.2.2.64/30	10.2.2.65 – 10.2.2.66	10.2.2.67
146	10.2.2.68/30	10.2.2.69 – 10.2.2.70	10.2.2.71
147	10.2.2.72/30	10.2.2.73 – 10.2.2.74	10.2.2.75
148	10.2.2.76/30	10.2.2.77 – 10.2.2.78	10.2.2.79
149	10.2.2.80/30	10.2.2.81 – 10.2.2.82	10.2.2.83
150	10.2.2.84/30	10.2.2.85 – 10.2.2.86	10.2.2.87
151	10.2.2.88/30	10.2.2.89 – 10.2.2.90	10.2.2.91
152	10.2.2.92/30	10.2.2.93 – 10.2.2.94	10.2.2.95
153	10.2.2.96/30	10.2.2.97 – 10.2.2.98	10.2.2.99
154	10.2.2.100/30	10.2.2.101 – 10.2.2.102	10.2.2.103
155	10.2.2.104/30	10.2.2.105 – 10.2.2.106	10.2.2.107
156	10.2.2.108/30	10.2.2.109 – 10.2.2.110	10.2.2.111
157	10.2.2.112/30	10.2.2.113 – 10.2.2.114	10.2.2.115
158	10.2.2.116/30	10.2.2.117 – 10.2.2.118	10.2.2.119
159	10.2.2.120/30	10.2.2.121 – 10.2.2.122	10.2.2.123
160	10.2.2.124/30	10.2.2.125 – 10.2.2.126	10.2.2.127
161	10.2.2.128/30	10.2.2.129 – 10.2.2.130	10.2.2.131
162	10.2.2.132/30	10.2.2.133 – 10.2.2.134	10.2.2.135
163	10.2.2.136/30	10.2.2.137 – 10.2.2.138	10.2.2.139
164	10.2.2.140/30	10.2.2.141 – 10.2.2.142	10.2.2.143
165	10.2.2.144/30	10.2.2.145 – 10.2.2.146	10.2.2.147
166	10.2.2.148/30	10.2.2.149 – 10.2.2.150	10.2.2.151
167	10.2.2.152/30	10.2.2.153 – 10.2.2.154	10.2.2.155
168	10.2.2.156/30	10.2.2.157 – 10.2.2.158	10.2.2.159
169	10.2.2.160/30	10.2.2.161 – 10.2.2.162	10.2.2.163
170	10.2.2.164/30	10.2.2.165 – 10.2.2.166	10.2.2.167
171	10.2.2.168/30	10.2.2.169 – 10.2.2.170	10.2.2.171
172	10.2.2.172/30	10.2.2.173 – 10.2.2.174	10.2.2.175
173	10.2.2.176/30	10.2.2.177 – 10.2.2.178	10.2.2.179
174	10.2.2.180/30	10.2.2.181 – 10.2.2.182	10.2.2.183
175	10.2.2.184/30	10.2.2.185 – 10.2.2.186	10.2.2.187
176	10.2.2.188/30	10.2.2.189 – 10.2.2.190	10.2.2.191
177	10.2.2.192/30	10.2.2.193 – 10.2.2.194	10.2.2.195
178	10.2.2.196/30	10.2.2.197 – 10.2.2.198	10.2.2.199
179	10.2.2.200/30	10.2.2.201 – 10.2.2.202	10.2.2.203
180	10.2.2.204/30	10.2.2.205 – 10.2.2.206	10.2.2.207
181	10.2.2.208/30	10.2.2.209 – 10.2.2.210	10.2.2.211
182	10.2.2.212/30	10.2.2.213 – 10.2.2.214	10.2.2.215
183	10.2.2.216/30	10.2.2.217 – 10.2.2.218	10.2.2.219
184	10.2.2.220/30	10.2.2.221 – 10.2.2.222	10.2.2.223
185	10.2.2.224/30	10.2.2.225 – 10.2.2.226	10.2.2.227
186	10.2.2.228/30	10.2.2.229 – 10.2.2.230	10.2.2.231
187	10.2.2.232/30	10.2.2.233 – 10.2.2.234	10.2.2.235
188	10.2.2.236/30	10.2.2.237 – 10.2.2.238	10.2.2.239
189	10.2.2.240/30	10.2.2.241 – 10.2.2.242	10.2.2.243
190	10.2.2.244/30	10.2.2.245 – 10.2.2.246	10.2.2.247
191	10.2.2.248/30	10.2.2.249 – 10.2.2.250	10.2.2.251
192	10.2.2.252/30	10.2.2.253 – 10.2.2.254	10.2.2.255
193	10.2.3.0/30	10.2.3.1 – 10.2.3.2	10.2.3.3
194	10.2.3.4/30	10.2.3.5 – 10.2.3.6	10.2.3.7
195	10.2.3.8/30	10.2.3.9 – 10.2.3.10	10.2.3.11
196	10.2.3.12/30	10.2.3.13 – 10.2.3.14	10.2.3.15
197	10.2.3.16/30	10.2.3.17 – 10.2.3.18	10.2.3.19
198	10.2.3.20/30	10.2.3.21 – 10.2.3.22	10.2.3.23
199	10.2.3.24/30	10.2.3.25 – 10.2.3.26	10.2.3.27
200	10.2.3.28/30	10.2.3.29 – 10.2.3.30	10.2.3.31
201	10.2.3.32/30	10.2.3.33 – 10.2.3.34	10.2.3.35
202	10.2.3.36/30	10.2.3.37 – 10.2.3.38	10.2.3.39
203	10.2.3.40/30	10.2.3.41 – 10.2.3.42	10.2.3.43
204	10.2.3.44/30	10.2.3.45 – 10.2.3.46	10.2.3.47
205	10.2.3.48/30	10.2.3.49 – 10.2.3.50	10.2.3.51
206	10.2.3.52/30	10.2.3.53 – 10.2.3.54	10.2.3.55
207	10.2.3.56/30	10.2.3.57 – 10.2.3.58	10.2.3.59
208	10.2.3.60/30	10.2.3.61 – 10.2.3.62	10.2.3.63
209	10.2.3.64/30	10.2.3.65 – 10.2.3.66	10.2.3.67
210	10.2.3.68/30	10.2.3.69 – 10.2.3.70	10.2.3.71
211	10.2.3.72/30	10.2.3.73 – 10.2.3.74	10.2.3.75
212	10.2.3.76/30	10.2.3.77 – 10.2.3.78	10.2.3.79
213	10.2.3.80/30	10.2.3.81 – 10.2.3.82	10.2.3.83
214	10.2.3.84/30	10.2.3.85 – 10.2.3.86	10.2.3.87
215	10.2.3.88/30	10.2.3.89 – 10.2.3.90	10.2.3.91
216	10.2.3.92/30	10.2.3.93 – 10.2.3.94	10.2.3.95
217	10.2.3.96/30	10.2.3.97 – 10.2.3.98	10.2.3.99
218	10.2.3.100/30	10.2.3.101 – 10.2.3.102	10.2.3.103
219	10.2.3.104/30	10.2.3.105 – 10.2.3.106	10.2.3.107
220	10.2.3.108/30	10.2.3.109 – 10.2.3.110	10.2.3.111
221	10.2.3.112/30	10.2.3.113 – 10.2.3.114	10.2.3.115
222	10.2.3.116/30	10.2.3.117 – 10.2.3.118	10.2.3.119
223	10.2.3.120/30	10.2.3.121 – 10.2.3.122	10.2.3.123
224	10.2.3.124/30	10.2.3.125 – 10.2.3.126	10.2.3.127
225	10.2.3.128/30	10.2.3.129 – 10.2.3.130	10.2.3.131
226	10.2.3.132/30	10.2.3.133 – 10.2.3.134	10.2.3.135
227	10.2.3.136/30	10.2.3.137 – 10.2.3.138	10.2.3.139
228	10.2.3.140/30	10.2.3.141 – 10.2.3.142	10.2.3.143
229	10.2.3.144/30	10.2.3.145 – 10.2.3.146	10.2.3.147
230	10.2.3.148/30	10.2.3.149 – 10.2.3.150	10.2.3.151
231	10.2.3.152/30	10.2.3.153 – 10.2.3.154	10.2.3.155
232	10.2.3.156/30	10.2.3.157 – 10.2.3.158	10.2.3.159
233	10.2.3.160/30	10.2.3.161 – 10.2.3.162	10.2.3.163
234	10.2.3.164/30	10.2.3.165 – 10.2.3.166	10.2.3.167
235	10.2.3.168/30	10.2.3.169 – 10.2.3.170	10.2.3.171
236	10.2.3.172/30	10.2.3.173 – 10.2.3.174	10.2.3.175
237	10.2.3.176/30	10.2.3.177 – 10.2.3.178	10.2.3.179
238	10.2.3.180/30	10.2.3.181 – 10.2.3.182	10.2.3.183
239	10.2.3.184/30	10.2.3.185 – 10.2.3.186	10.2.3.187
240	10.2.3.188/30	10.2.3.189 – 10.2.3.190	10.2.3.191
241	10.2.3.192/30	10.2.3.193 – 10.2.3.194	10.2.3.195
242	10.2.3.196/30	10.2.3.197 – 10.2.3.198	10.2.3.199
243	10.2.3.200/30	10.2.3.201 – 10.2.3.202	10.2.3.203
244	10.2.3.204/30	10.2.3.205 – 10.2.3.206	10.2.3.207
245	10.2.3.208/30	10.2.3.209 – 10.2.3.210	10.2.3.211
246	10.2.3.212/30	10.2.3.213 – 10.2.3.214	10.2.3.215
247	10.2.3.216/30	10.2.3.217 – 10.2.3.218	10.2.3.219
248	10.2.3.220/30	10.2.3.221 – 10.2.3.222	10.2.3.223
249	10.2.3.224/30	10.2.3.225 – 10.2.3.226	10.2.3.227
250	10.2.3.228/30	10.2.3.229 – 10.2.3.230	10.2.3.231
251	10.2.3.232/30	10.2.3.233 – 10.2.3.234	10.2.3.235
252	10.2.3.236/30	10.2.3.237 – 10.2.3.238	10.2.3.239
253	10.2.3.240/30	10.2.3.241 – 10.2.3.242	10.2.3.243
254	10.2.3.244/30	10.2.3.245 – 10.2.3.246	10.2.3.247
255	10.2.3.248/30	10.2.3.249 – 10.2.3.250	10.2.3.251
256	10.2.3.252/30	10.2.3.253 – 10.2.3.254	10.2.3.255

showing 256 of 512

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 →