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)10.5.56.0/21

network10.5.56.0/21

broadcast10.5.63.255

first host10.5.56.1

last host10.5.63.254

subnet mask255.255.248.0

wildcard0.0.7.255

addresses2,048

usable hosts2,046

classA

ipcalc 10.5.56.0/21

address00001010.00000101.00111000.00000000

subnet mask11111111.11111111.11111000.00000000

network00001010.00000101.00111000.00000000

broadcast00001010.00000101.00111111.11111111

green = network part, grey = host part

hex0x0a053800

decimal168114176

reverse dns0.56.5.10.in-addr.arpa

ipv4-mapped::ffff:a05:3800

/21 split into /29 · 256 subnets

close ×

#	network	host range	broadcast
1	10.5.56.0/29	10.5.56.1 – 10.5.56.6	10.5.56.7
2	10.5.56.8/29	10.5.56.9 – 10.5.56.14	10.5.56.15
3	10.5.56.16/29	10.5.56.17 – 10.5.56.22	10.5.56.23
4	10.5.56.24/29	10.5.56.25 – 10.5.56.30	10.5.56.31
5	10.5.56.32/29	10.5.56.33 – 10.5.56.38	10.5.56.39
6	10.5.56.40/29	10.5.56.41 – 10.5.56.46	10.5.56.47
7	10.5.56.48/29	10.5.56.49 – 10.5.56.54	10.5.56.55
8	10.5.56.56/29	10.5.56.57 – 10.5.56.62	10.5.56.63
9	10.5.56.64/29	10.5.56.65 – 10.5.56.70	10.5.56.71
10	10.5.56.72/29	10.5.56.73 – 10.5.56.78	10.5.56.79
11	10.5.56.80/29	10.5.56.81 – 10.5.56.86	10.5.56.87
12	10.5.56.88/29	10.5.56.89 – 10.5.56.94	10.5.56.95
13	10.5.56.96/29	10.5.56.97 – 10.5.56.102	10.5.56.103
14	10.5.56.104/29	10.5.56.105 – 10.5.56.110	10.5.56.111
15	10.5.56.112/29	10.5.56.113 – 10.5.56.118	10.5.56.119
16	10.5.56.120/29	10.5.56.121 – 10.5.56.126	10.5.56.127
17	10.5.56.128/29	10.5.56.129 – 10.5.56.134	10.5.56.135
18	10.5.56.136/29	10.5.56.137 – 10.5.56.142	10.5.56.143
19	10.5.56.144/29	10.5.56.145 – 10.5.56.150	10.5.56.151
20	10.5.56.152/29	10.5.56.153 – 10.5.56.158	10.5.56.159
21	10.5.56.160/29	10.5.56.161 – 10.5.56.166	10.5.56.167
22	10.5.56.168/29	10.5.56.169 – 10.5.56.174	10.5.56.175
23	10.5.56.176/29	10.5.56.177 – 10.5.56.182	10.5.56.183
24	10.5.56.184/29	10.5.56.185 – 10.5.56.190	10.5.56.191
25	10.5.56.192/29	10.5.56.193 – 10.5.56.198	10.5.56.199
26	10.5.56.200/29	10.5.56.201 – 10.5.56.206	10.5.56.207
27	10.5.56.208/29	10.5.56.209 – 10.5.56.214	10.5.56.215
28	10.5.56.216/29	10.5.56.217 – 10.5.56.222	10.5.56.223
29	10.5.56.224/29	10.5.56.225 – 10.5.56.230	10.5.56.231
30	10.5.56.232/29	10.5.56.233 – 10.5.56.238	10.5.56.239
31	10.5.56.240/29	10.5.56.241 – 10.5.56.246	10.5.56.247
32	10.5.56.248/29	10.5.56.249 – 10.5.56.254	10.5.56.255
33	10.5.57.0/29	10.5.57.1 – 10.5.57.6	10.5.57.7
34	10.5.57.8/29	10.5.57.9 – 10.5.57.14	10.5.57.15
35	10.5.57.16/29	10.5.57.17 – 10.5.57.22	10.5.57.23
36	10.5.57.24/29	10.5.57.25 – 10.5.57.30	10.5.57.31
37	10.5.57.32/29	10.5.57.33 – 10.5.57.38	10.5.57.39
38	10.5.57.40/29	10.5.57.41 – 10.5.57.46	10.5.57.47
39	10.5.57.48/29	10.5.57.49 – 10.5.57.54	10.5.57.55
40	10.5.57.56/29	10.5.57.57 – 10.5.57.62	10.5.57.63
41	10.5.57.64/29	10.5.57.65 – 10.5.57.70	10.5.57.71
42	10.5.57.72/29	10.5.57.73 – 10.5.57.78	10.5.57.79
43	10.5.57.80/29	10.5.57.81 – 10.5.57.86	10.5.57.87
44	10.5.57.88/29	10.5.57.89 – 10.5.57.94	10.5.57.95
45	10.5.57.96/29	10.5.57.97 – 10.5.57.102	10.5.57.103
46	10.5.57.104/29	10.5.57.105 – 10.5.57.110	10.5.57.111
47	10.5.57.112/29	10.5.57.113 – 10.5.57.118	10.5.57.119
48	10.5.57.120/29	10.5.57.121 – 10.5.57.126	10.5.57.127
49	10.5.57.128/29	10.5.57.129 – 10.5.57.134	10.5.57.135
50	10.5.57.136/29	10.5.57.137 – 10.5.57.142	10.5.57.143
51	10.5.57.144/29	10.5.57.145 – 10.5.57.150	10.5.57.151
52	10.5.57.152/29	10.5.57.153 – 10.5.57.158	10.5.57.159
53	10.5.57.160/29	10.5.57.161 – 10.5.57.166	10.5.57.167
54	10.5.57.168/29	10.5.57.169 – 10.5.57.174	10.5.57.175
55	10.5.57.176/29	10.5.57.177 – 10.5.57.182	10.5.57.183
56	10.5.57.184/29	10.5.57.185 – 10.5.57.190	10.5.57.191
57	10.5.57.192/29	10.5.57.193 – 10.5.57.198	10.5.57.199
58	10.5.57.200/29	10.5.57.201 – 10.5.57.206	10.5.57.207
59	10.5.57.208/29	10.5.57.209 – 10.5.57.214	10.5.57.215
60	10.5.57.216/29	10.5.57.217 – 10.5.57.222	10.5.57.223
61	10.5.57.224/29	10.5.57.225 – 10.5.57.230	10.5.57.231
62	10.5.57.232/29	10.5.57.233 – 10.5.57.238	10.5.57.239
63	10.5.57.240/29	10.5.57.241 – 10.5.57.246	10.5.57.247
64	10.5.57.248/29	10.5.57.249 – 10.5.57.254	10.5.57.255
65	10.5.58.0/29	10.5.58.1 – 10.5.58.6	10.5.58.7
66	10.5.58.8/29	10.5.58.9 – 10.5.58.14	10.5.58.15
67	10.5.58.16/29	10.5.58.17 – 10.5.58.22	10.5.58.23
68	10.5.58.24/29	10.5.58.25 – 10.5.58.30	10.5.58.31
69	10.5.58.32/29	10.5.58.33 – 10.5.58.38	10.5.58.39
70	10.5.58.40/29	10.5.58.41 – 10.5.58.46	10.5.58.47
71	10.5.58.48/29	10.5.58.49 – 10.5.58.54	10.5.58.55
72	10.5.58.56/29	10.5.58.57 – 10.5.58.62	10.5.58.63
73	10.5.58.64/29	10.5.58.65 – 10.5.58.70	10.5.58.71
74	10.5.58.72/29	10.5.58.73 – 10.5.58.78	10.5.58.79
75	10.5.58.80/29	10.5.58.81 – 10.5.58.86	10.5.58.87
76	10.5.58.88/29	10.5.58.89 – 10.5.58.94	10.5.58.95
77	10.5.58.96/29	10.5.58.97 – 10.5.58.102	10.5.58.103
78	10.5.58.104/29	10.5.58.105 – 10.5.58.110	10.5.58.111
79	10.5.58.112/29	10.5.58.113 – 10.5.58.118	10.5.58.119
80	10.5.58.120/29	10.5.58.121 – 10.5.58.126	10.5.58.127
81	10.5.58.128/29	10.5.58.129 – 10.5.58.134	10.5.58.135
82	10.5.58.136/29	10.5.58.137 – 10.5.58.142	10.5.58.143
83	10.5.58.144/29	10.5.58.145 – 10.5.58.150	10.5.58.151
84	10.5.58.152/29	10.5.58.153 – 10.5.58.158	10.5.58.159
85	10.5.58.160/29	10.5.58.161 – 10.5.58.166	10.5.58.167
86	10.5.58.168/29	10.5.58.169 – 10.5.58.174	10.5.58.175
87	10.5.58.176/29	10.5.58.177 – 10.5.58.182	10.5.58.183
88	10.5.58.184/29	10.5.58.185 – 10.5.58.190	10.5.58.191
89	10.5.58.192/29	10.5.58.193 – 10.5.58.198	10.5.58.199
90	10.5.58.200/29	10.5.58.201 – 10.5.58.206	10.5.58.207
91	10.5.58.208/29	10.5.58.209 – 10.5.58.214	10.5.58.215
92	10.5.58.216/29	10.5.58.217 – 10.5.58.222	10.5.58.223
93	10.5.58.224/29	10.5.58.225 – 10.5.58.230	10.5.58.231
94	10.5.58.232/29	10.5.58.233 – 10.5.58.238	10.5.58.239
95	10.5.58.240/29	10.5.58.241 – 10.5.58.246	10.5.58.247
96	10.5.58.248/29	10.5.58.249 – 10.5.58.254	10.5.58.255
97	10.5.59.0/29	10.5.59.1 – 10.5.59.6	10.5.59.7
98	10.5.59.8/29	10.5.59.9 – 10.5.59.14	10.5.59.15
99	10.5.59.16/29	10.5.59.17 – 10.5.59.22	10.5.59.23
100	10.5.59.24/29	10.5.59.25 – 10.5.59.30	10.5.59.31
101	10.5.59.32/29	10.5.59.33 – 10.5.59.38	10.5.59.39
102	10.5.59.40/29	10.5.59.41 – 10.5.59.46	10.5.59.47
103	10.5.59.48/29	10.5.59.49 – 10.5.59.54	10.5.59.55
104	10.5.59.56/29	10.5.59.57 – 10.5.59.62	10.5.59.63
105	10.5.59.64/29	10.5.59.65 – 10.5.59.70	10.5.59.71
106	10.5.59.72/29	10.5.59.73 – 10.5.59.78	10.5.59.79
107	10.5.59.80/29	10.5.59.81 – 10.5.59.86	10.5.59.87
108	10.5.59.88/29	10.5.59.89 – 10.5.59.94	10.5.59.95
109	10.5.59.96/29	10.5.59.97 – 10.5.59.102	10.5.59.103
110	10.5.59.104/29	10.5.59.105 – 10.5.59.110	10.5.59.111
111	10.5.59.112/29	10.5.59.113 – 10.5.59.118	10.5.59.119
112	10.5.59.120/29	10.5.59.121 – 10.5.59.126	10.5.59.127
113	10.5.59.128/29	10.5.59.129 – 10.5.59.134	10.5.59.135
114	10.5.59.136/29	10.5.59.137 – 10.5.59.142	10.5.59.143
115	10.5.59.144/29	10.5.59.145 – 10.5.59.150	10.5.59.151
116	10.5.59.152/29	10.5.59.153 – 10.5.59.158	10.5.59.159
117	10.5.59.160/29	10.5.59.161 – 10.5.59.166	10.5.59.167
118	10.5.59.168/29	10.5.59.169 – 10.5.59.174	10.5.59.175
119	10.5.59.176/29	10.5.59.177 – 10.5.59.182	10.5.59.183
120	10.5.59.184/29	10.5.59.185 – 10.5.59.190	10.5.59.191
121	10.5.59.192/29	10.5.59.193 – 10.5.59.198	10.5.59.199
122	10.5.59.200/29	10.5.59.201 – 10.5.59.206	10.5.59.207
123	10.5.59.208/29	10.5.59.209 – 10.5.59.214	10.5.59.215
124	10.5.59.216/29	10.5.59.217 – 10.5.59.222	10.5.59.223
125	10.5.59.224/29	10.5.59.225 – 10.5.59.230	10.5.59.231
126	10.5.59.232/29	10.5.59.233 – 10.5.59.238	10.5.59.239
127	10.5.59.240/29	10.5.59.241 – 10.5.59.246	10.5.59.247
128	10.5.59.248/29	10.5.59.249 – 10.5.59.254	10.5.59.255
129	10.5.60.0/29	10.5.60.1 – 10.5.60.6	10.5.60.7
130	10.5.60.8/29	10.5.60.9 – 10.5.60.14	10.5.60.15
131	10.5.60.16/29	10.5.60.17 – 10.5.60.22	10.5.60.23
132	10.5.60.24/29	10.5.60.25 – 10.5.60.30	10.5.60.31
133	10.5.60.32/29	10.5.60.33 – 10.5.60.38	10.5.60.39
134	10.5.60.40/29	10.5.60.41 – 10.5.60.46	10.5.60.47
135	10.5.60.48/29	10.5.60.49 – 10.5.60.54	10.5.60.55
136	10.5.60.56/29	10.5.60.57 – 10.5.60.62	10.5.60.63
137	10.5.60.64/29	10.5.60.65 – 10.5.60.70	10.5.60.71
138	10.5.60.72/29	10.5.60.73 – 10.5.60.78	10.5.60.79
139	10.5.60.80/29	10.5.60.81 – 10.5.60.86	10.5.60.87
140	10.5.60.88/29	10.5.60.89 – 10.5.60.94	10.5.60.95
141	10.5.60.96/29	10.5.60.97 – 10.5.60.102	10.5.60.103
142	10.5.60.104/29	10.5.60.105 – 10.5.60.110	10.5.60.111
143	10.5.60.112/29	10.5.60.113 – 10.5.60.118	10.5.60.119
144	10.5.60.120/29	10.5.60.121 – 10.5.60.126	10.5.60.127
145	10.5.60.128/29	10.5.60.129 – 10.5.60.134	10.5.60.135
146	10.5.60.136/29	10.5.60.137 – 10.5.60.142	10.5.60.143
147	10.5.60.144/29	10.5.60.145 – 10.5.60.150	10.5.60.151
148	10.5.60.152/29	10.5.60.153 – 10.5.60.158	10.5.60.159
149	10.5.60.160/29	10.5.60.161 – 10.5.60.166	10.5.60.167
150	10.5.60.168/29	10.5.60.169 – 10.5.60.174	10.5.60.175
151	10.5.60.176/29	10.5.60.177 – 10.5.60.182	10.5.60.183
152	10.5.60.184/29	10.5.60.185 – 10.5.60.190	10.5.60.191
153	10.5.60.192/29	10.5.60.193 – 10.5.60.198	10.5.60.199
154	10.5.60.200/29	10.5.60.201 – 10.5.60.206	10.5.60.207
155	10.5.60.208/29	10.5.60.209 – 10.5.60.214	10.5.60.215
156	10.5.60.216/29	10.5.60.217 – 10.5.60.222	10.5.60.223
157	10.5.60.224/29	10.5.60.225 – 10.5.60.230	10.5.60.231
158	10.5.60.232/29	10.5.60.233 – 10.5.60.238	10.5.60.239
159	10.5.60.240/29	10.5.60.241 – 10.5.60.246	10.5.60.247
160	10.5.60.248/29	10.5.60.249 – 10.5.60.254	10.5.60.255
161	10.5.61.0/29	10.5.61.1 – 10.5.61.6	10.5.61.7
162	10.5.61.8/29	10.5.61.9 – 10.5.61.14	10.5.61.15
163	10.5.61.16/29	10.5.61.17 – 10.5.61.22	10.5.61.23
164	10.5.61.24/29	10.5.61.25 – 10.5.61.30	10.5.61.31
165	10.5.61.32/29	10.5.61.33 – 10.5.61.38	10.5.61.39
166	10.5.61.40/29	10.5.61.41 – 10.5.61.46	10.5.61.47
167	10.5.61.48/29	10.5.61.49 – 10.5.61.54	10.5.61.55
168	10.5.61.56/29	10.5.61.57 – 10.5.61.62	10.5.61.63
169	10.5.61.64/29	10.5.61.65 – 10.5.61.70	10.5.61.71
170	10.5.61.72/29	10.5.61.73 – 10.5.61.78	10.5.61.79
171	10.5.61.80/29	10.5.61.81 – 10.5.61.86	10.5.61.87
172	10.5.61.88/29	10.5.61.89 – 10.5.61.94	10.5.61.95
173	10.5.61.96/29	10.5.61.97 – 10.5.61.102	10.5.61.103
174	10.5.61.104/29	10.5.61.105 – 10.5.61.110	10.5.61.111
175	10.5.61.112/29	10.5.61.113 – 10.5.61.118	10.5.61.119
176	10.5.61.120/29	10.5.61.121 – 10.5.61.126	10.5.61.127
177	10.5.61.128/29	10.5.61.129 – 10.5.61.134	10.5.61.135
178	10.5.61.136/29	10.5.61.137 – 10.5.61.142	10.5.61.143
179	10.5.61.144/29	10.5.61.145 – 10.5.61.150	10.5.61.151
180	10.5.61.152/29	10.5.61.153 – 10.5.61.158	10.5.61.159
181	10.5.61.160/29	10.5.61.161 – 10.5.61.166	10.5.61.167
182	10.5.61.168/29	10.5.61.169 – 10.5.61.174	10.5.61.175
183	10.5.61.176/29	10.5.61.177 – 10.5.61.182	10.5.61.183
184	10.5.61.184/29	10.5.61.185 – 10.5.61.190	10.5.61.191
185	10.5.61.192/29	10.5.61.193 – 10.5.61.198	10.5.61.199
186	10.5.61.200/29	10.5.61.201 – 10.5.61.206	10.5.61.207
187	10.5.61.208/29	10.5.61.209 – 10.5.61.214	10.5.61.215
188	10.5.61.216/29	10.5.61.217 – 10.5.61.222	10.5.61.223
189	10.5.61.224/29	10.5.61.225 – 10.5.61.230	10.5.61.231
190	10.5.61.232/29	10.5.61.233 – 10.5.61.238	10.5.61.239
191	10.5.61.240/29	10.5.61.241 – 10.5.61.246	10.5.61.247
192	10.5.61.248/29	10.5.61.249 – 10.5.61.254	10.5.61.255
193	10.5.62.0/29	10.5.62.1 – 10.5.62.6	10.5.62.7
194	10.5.62.8/29	10.5.62.9 – 10.5.62.14	10.5.62.15
195	10.5.62.16/29	10.5.62.17 – 10.5.62.22	10.5.62.23
196	10.5.62.24/29	10.5.62.25 – 10.5.62.30	10.5.62.31
197	10.5.62.32/29	10.5.62.33 – 10.5.62.38	10.5.62.39
198	10.5.62.40/29	10.5.62.41 – 10.5.62.46	10.5.62.47
199	10.5.62.48/29	10.5.62.49 – 10.5.62.54	10.5.62.55
200	10.5.62.56/29	10.5.62.57 – 10.5.62.62	10.5.62.63
201	10.5.62.64/29	10.5.62.65 – 10.5.62.70	10.5.62.71
202	10.5.62.72/29	10.5.62.73 – 10.5.62.78	10.5.62.79
203	10.5.62.80/29	10.5.62.81 – 10.5.62.86	10.5.62.87
204	10.5.62.88/29	10.5.62.89 – 10.5.62.94	10.5.62.95
205	10.5.62.96/29	10.5.62.97 – 10.5.62.102	10.5.62.103
206	10.5.62.104/29	10.5.62.105 – 10.5.62.110	10.5.62.111
207	10.5.62.112/29	10.5.62.113 – 10.5.62.118	10.5.62.119
208	10.5.62.120/29	10.5.62.121 – 10.5.62.126	10.5.62.127
209	10.5.62.128/29	10.5.62.129 – 10.5.62.134	10.5.62.135
210	10.5.62.136/29	10.5.62.137 – 10.5.62.142	10.5.62.143
211	10.5.62.144/29	10.5.62.145 – 10.5.62.150	10.5.62.151
212	10.5.62.152/29	10.5.62.153 – 10.5.62.158	10.5.62.159
213	10.5.62.160/29	10.5.62.161 – 10.5.62.166	10.5.62.167
214	10.5.62.168/29	10.5.62.169 – 10.5.62.174	10.5.62.175
215	10.5.62.176/29	10.5.62.177 – 10.5.62.182	10.5.62.183
216	10.5.62.184/29	10.5.62.185 – 10.5.62.190	10.5.62.191
217	10.5.62.192/29	10.5.62.193 – 10.5.62.198	10.5.62.199
218	10.5.62.200/29	10.5.62.201 – 10.5.62.206	10.5.62.207
219	10.5.62.208/29	10.5.62.209 – 10.5.62.214	10.5.62.215
220	10.5.62.216/29	10.5.62.217 – 10.5.62.222	10.5.62.223
221	10.5.62.224/29	10.5.62.225 – 10.5.62.230	10.5.62.231
222	10.5.62.232/29	10.5.62.233 – 10.5.62.238	10.5.62.239
223	10.5.62.240/29	10.5.62.241 – 10.5.62.246	10.5.62.247
224	10.5.62.248/29	10.5.62.249 – 10.5.62.254	10.5.62.255
225	10.5.63.0/29	10.5.63.1 – 10.5.63.6	10.5.63.7
226	10.5.63.8/29	10.5.63.9 – 10.5.63.14	10.5.63.15
227	10.5.63.16/29	10.5.63.17 – 10.5.63.22	10.5.63.23
228	10.5.63.24/29	10.5.63.25 – 10.5.63.30	10.5.63.31
229	10.5.63.32/29	10.5.63.33 – 10.5.63.38	10.5.63.39
230	10.5.63.40/29	10.5.63.41 – 10.5.63.46	10.5.63.47
231	10.5.63.48/29	10.5.63.49 – 10.5.63.54	10.5.63.55
232	10.5.63.56/29	10.5.63.57 – 10.5.63.62	10.5.63.63
233	10.5.63.64/29	10.5.63.65 – 10.5.63.70	10.5.63.71
234	10.5.63.72/29	10.5.63.73 – 10.5.63.78	10.5.63.79
235	10.5.63.80/29	10.5.63.81 – 10.5.63.86	10.5.63.87
236	10.5.63.88/29	10.5.63.89 – 10.5.63.94	10.5.63.95
237	10.5.63.96/29	10.5.63.97 – 10.5.63.102	10.5.63.103
238	10.5.63.104/29	10.5.63.105 – 10.5.63.110	10.5.63.111
239	10.5.63.112/29	10.5.63.113 – 10.5.63.118	10.5.63.119
240	10.5.63.120/29	10.5.63.121 – 10.5.63.126	10.5.63.127
241	10.5.63.128/29	10.5.63.129 – 10.5.63.134	10.5.63.135
242	10.5.63.136/29	10.5.63.137 – 10.5.63.142	10.5.63.143
243	10.5.63.144/29	10.5.63.145 – 10.5.63.150	10.5.63.151
244	10.5.63.152/29	10.5.63.153 – 10.5.63.158	10.5.63.159
245	10.5.63.160/29	10.5.63.161 – 10.5.63.166	10.5.63.167
246	10.5.63.168/29	10.5.63.169 – 10.5.63.174	10.5.63.175
247	10.5.63.176/29	10.5.63.177 – 10.5.63.182	10.5.63.183
248	10.5.63.184/29	10.5.63.185 – 10.5.63.190	10.5.63.191
249	10.5.63.192/29	10.5.63.193 – 10.5.63.198	10.5.63.199
250	10.5.63.200/29	10.5.63.201 – 10.5.63.206	10.5.63.207
251	10.5.63.208/29	10.5.63.209 – 10.5.63.214	10.5.63.215
252	10.5.63.216/29	10.5.63.217 – 10.5.63.222	10.5.63.223
253	10.5.63.224/29	10.5.63.225 – 10.5.63.230	10.5.63.231
254	10.5.63.232/29	10.5.63.233 – 10.5.63.238	10.5.63.239
255	10.5.63.240/29	10.5.63.241 – 10.5.63.246	10.5.63.247
256	10.5.63.248/29	10.5.63.249 – 10.5.63.254	10.5.63.255

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 →