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)10.21.96.0/19

network10.21.96.0/19

broadcast10.21.127.255

first host10.21.96.1

last host10.21.127.254

subnet mask255.255.224.0

wildcard0.0.31.255

addresses8,192

usable hosts8,190

classA

ipcalc 10.21.96.0/19

address00001010.00010101.01100000.00000000

subnet mask11111111.11111111.11100000.00000000

network00001010.00010101.01100000.00000000

broadcast00001010.00010101.01111111.11111111

green = network part, grey = host part

hex0x0a156000

decimal169172992

reverse dns0.96.21.10.in-addr.arpa

ipv4-mapped::ffff:a15:6000

/19 split into /27 · 256 subnets

close ×

#	network	host range	broadcast
1	10.21.96.0/27	10.21.96.1 – 10.21.96.30	10.21.96.31
2	10.21.96.32/27	10.21.96.33 – 10.21.96.62	10.21.96.63
3	10.21.96.64/27	10.21.96.65 – 10.21.96.94	10.21.96.95
4	10.21.96.96/27	10.21.96.97 – 10.21.96.126	10.21.96.127
5	10.21.96.128/27	10.21.96.129 – 10.21.96.158	10.21.96.159
6	10.21.96.160/27	10.21.96.161 – 10.21.96.190	10.21.96.191
7	10.21.96.192/27	10.21.96.193 – 10.21.96.222	10.21.96.223
8	10.21.96.224/27	10.21.96.225 – 10.21.96.254	10.21.96.255
9	10.21.97.0/27	10.21.97.1 – 10.21.97.30	10.21.97.31
10	10.21.97.32/27	10.21.97.33 – 10.21.97.62	10.21.97.63
11	10.21.97.64/27	10.21.97.65 – 10.21.97.94	10.21.97.95
12	10.21.97.96/27	10.21.97.97 – 10.21.97.126	10.21.97.127
13	10.21.97.128/27	10.21.97.129 – 10.21.97.158	10.21.97.159
14	10.21.97.160/27	10.21.97.161 – 10.21.97.190	10.21.97.191
15	10.21.97.192/27	10.21.97.193 – 10.21.97.222	10.21.97.223
16	10.21.97.224/27	10.21.97.225 – 10.21.97.254	10.21.97.255
17	10.21.98.0/27	10.21.98.1 – 10.21.98.30	10.21.98.31
18	10.21.98.32/27	10.21.98.33 – 10.21.98.62	10.21.98.63
19	10.21.98.64/27	10.21.98.65 – 10.21.98.94	10.21.98.95
20	10.21.98.96/27	10.21.98.97 – 10.21.98.126	10.21.98.127
21	10.21.98.128/27	10.21.98.129 – 10.21.98.158	10.21.98.159
22	10.21.98.160/27	10.21.98.161 – 10.21.98.190	10.21.98.191
23	10.21.98.192/27	10.21.98.193 – 10.21.98.222	10.21.98.223
24	10.21.98.224/27	10.21.98.225 – 10.21.98.254	10.21.98.255
25	10.21.99.0/27	10.21.99.1 – 10.21.99.30	10.21.99.31
26	10.21.99.32/27	10.21.99.33 – 10.21.99.62	10.21.99.63
27	10.21.99.64/27	10.21.99.65 – 10.21.99.94	10.21.99.95
28	10.21.99.96/27	10.21.99.97 – 10.21.99.126	10.21.99.127
29	10.21.99.128/27	10.21.99.129 – 10.21.99.158	10.21.99.159
30	10.21.99.160/27	10.21.99.161 – 10.21.99.190	10.21.99.191
31	10.21.99.192/27	10.21.99.193 – 10.21.99.222	10.21.99.223
32	10.21.99.224/27	10.21.99.225 – 10.21.99.254	10.21.99.255
33	10.21.100.0/27	10.21.100.1 – 10.21.100.30	10.21.100.31
34	10.21.100.32/27	10.21.100.33 – 10.21.100.62	10.21.100.63
35	10.21.100.64/27	10.21.100.65 – 10.21.100.94	10.21.100.95
36	10.21.100.96/27	10.21.100.97 – 10.21.100.126	10.21.100.127
37	10.21.100.128/27	10.21.100.129 – 10.21.100.158	10.21.100.159
38	10.21.100.160/27	10.21.100.161 – 10.21.100.190	10.21.100.191
39	10.21.100.192/27	10.21.100.193 – 10.21.100.222	10.21.100.223
40	10.21.100.224/27	10.21.100.225 – 10.21.100.254	10.21.100.255
41	10.21.101.0/27	10.21.101.1 – 10.21.101.30	10.21.101.31
42	10.21.101.32/27	10.21.101.33 – 10.21.101.62	10.21.101.63
43	10.21.101.64/27	10.21.101.65 – 10.21.101.94	10.21.101.95
44	10.21.101.96/27	10.21.101.97 – 10.21.101.126	10.21.101.127
45	10.21.101.128/27	10.21.101.129 – 10.21.101.158	10.21.101.159
46	10.21.101.160/27	10.21.101.161 – 10.21.101.190	10.21.101.191
47	10.21.101.192/27	10.21.101.193 – 10.21.101.222	10.21.101.223
48	10.21.101.224/27	10.21.101.225 – 10.21.101.254	10.21.101.255
49	10.21.102.0/27	10.21.102.1 – 10.21.102.30	10.21.102.31
50	10.21.102.32/27	10.21.102.33 – 10.21.102.62	10.21.102.63
51	10.21.102.64/27	10.21.102.65 – 10.21.102.94	10.21.102.95
52	10.21.102.96/27	10.21.102.97 – 10.21.102.126	10.21.102.127
53	10.21.102.128/27	10.21.102.129 – 10.21.102.158	10.21.102.159
54	10.21.102.160/27	10.21.102.161 – 10.21.102.190	10.21.102.191
55	10.21.102.192/27	10.21.102.193 – 10.21.102.222	10.21.102.223
56	10.21.102.224/27	10.21.102.225 – 10.21.102.254	10.21.102.255
57	10.21.103.0/27	10.21.103.1 – 10.21.103.30	10.21.103.31
58	10.21.103.32/27	10.21.103.33 – 10.21.103.62	10.21.103.63
59	10.21.103.64/27	10.21.103.65 – 10.21.103.94	10.21.103.95
60	10.21.103.96/27	10.21.103.97 – 10.21.103.126	10.21.103.127
61	10.21.103.128/27	10.21.103.129 – 10.21.103.158	10.21.103.159
62	10.21.103.160/27	10.21.103.161 – 10.21.103.190	10.21.103.191
63	10.21.103.192/27	10.21.103.193 – 10.21.103.222	10.21.103.223
64	10.21.103.224/27	10.21.103.225 – 10.21.103.254	10.21.103.255
65	10.21.104.0/27	10.21.104.1 – 10.21.104.30	10.21.104.31
66	10.21.104.32/27	10.21.104.33 – 10.21.104.62	10.21.104.63
67	10.21.104.64/27	10.21.104.65 – 10.21.104.94	10.21.104.95
68	10.21.104.96/27	10.21.104.97 – 10.21.104.126	10.21.104.127
69	10.21.104.128/27	10.21.104.129 – 10.21.104.158	10.21.104.159
70	10.21.104.160/27	10.21.104.161 – 10.21.104.190	10.21.104.191
71	10.21.104.192/27	10.21.104.193 – 10.21.104.222	10.21.104.223
72	10.21.104.224/27	10.21.104.225 – 10.21.104.254	10.21.104.255
73	10.21.105.0/27	10.21.105.1 – 10.21.105.30	10.21.105.31
74	10.21.105.32/27	10.21.105.33 – 10.21.105.62	10.21.105.63
75	10.21.105.64/27	10.21.105.65 – 10.21.105.94	10.21.105.95
76	10.21.105.96/27	10.21.105.97 – 10.21.105.126	10.21.105.127
77	10.21.105.128/27	10.21.105.129 – 10.21.105.158	10.21.105.159
78	10.21.105.160/27	10.21.105.161 – 10.21.105.190	10.21.105.191
79	10.21.105.192/27	10.21.105.193 – 10.21.105.222	10.21.105.223
80	10.21.105.224/27	10.21.105.225 – 10.21.105.254	10.21.105.255
81	10.21.106.0/27	10.21.106.1 – 10.21.106.30	10.21.106.31
82	10.21.106.32/27	10.21.106.33 – 10.21.106.62	10.21.106.63
83	10.21.106.64/27	10.21.106.65 – 10.21.106.94	10.21.106.95
84	10.21.106.96/27	10.21.106.97 – 10.21.106.126	10.21.106.127
85	10.21.106.128/27	10.21.106.129 – 10.21.106.158	10.21.106.159
86	10.21.106.160/27	10.21.106.161 – 10.21.106.190	10.21.106.191
87	10.21.106.192/27	10.21.106.193 – 10.21.106.222	10.21.106.223
88	10.21.106.224/27	10.21.106.225 – 10.21.106.254	10.21.106.255
89	10.21.107.0/27	10.21.107.1 – 10.21.107.30	10.21.107.31
90	10.21.107.32/27	10.21.107.33 – 10.21.107.62	10.21.107.63
91	10.21.107.64/27	10.21.107.65 – 10.21.107.94	10.21.107.95
92	10.21.107.96/27	10.21.107.97 – 10.21.107.126	10.21.107.127
93	10.21.107.128/27	10.21.107.129 – 10.21.107.158	10.21.107.159
94	10.21.107.160/27	10.21.107.161 – 10.21.107.190	10.21.107.191
95	10.21.107.192/27	10.21.107.193 – 10.21.107.222	10.21.107.223
96	10.21.107.224/27	10.21.107.225 – 10.21.107.254	10.21.107.255
97	10.21.108.0/27	10.21.108.1 – 10.21.108.30	10.21.108.31
98	10.21.108.32/27	10.21.108.33 – 10.21.108.62	10.21.108.63
99	10.21.108.64/27	10.21.108.65 – 10.21.108.94	10.21.108.95
100	10.21.108.96/27	10.21.108.97 – 10.21.108.126	10.21.108.127
101	10.21.108.128/27	10.21.108.129 – 10.21.108.158	10.21.108.159
102	10.21.108.160/27	10.21.108.161 – 10.21.108.190	10.21.108.191
103	10.21.108.192/27	10.21.108.193 – 10.21.108.222	10.21.108.223
104	10.21.108.224/27	10.21.108.225 – 10.21.108.254	10.21.108.255
105	10.21.109.0/27	10.21.109.1 – 10.21.109.30	10.21.109.31
106	10.21.109.32/27	10.21.109.33 – 10.21.109.62	10.21.109.63
107	10.21.109.64/27	10.21.109.65 – 10.21.109.94	10.21.109.95
108	10.21.109.96/27	10.21.109.97 – 10.21.109.126	10.21.109.127
109	10.21.109.128/27	10.21.109.129 – 10.21.109.158	10.21.109.159
110	10.21.109.160/27	10.21.109.161 – 10.21.109.190	10.21.109.191
111	10.21.109.192/27	10.21.109.193 – 10.21.109.222	10.21.109.223
112	10.21.109.224/27	10.21.109.225 – 10.21.109.254	10.21.109.255
113	10.21.110.0/27	10.21.110.1 – 10.21.110.30	10.21.110.31
114	10.21.110.32/27	10.21.110.33 – 10.21.110.62	10.21.110.63
115	10.21.110.64/27	10.21.110.65 – 10.21.110.94	10.21.110.95
116	10.21.110.96/27	10.21.110.97 – 10.21.110.126	10.21.110.127
117	10.21.110.128/27	10.21.110.129 – 10.21.110.158	10.21.110.159
118	10.21.110.160/27	10.21.110.161 – 10.21.110.190	10.21.110.191
119	10.21.110.192/27	10.21.110.193 – 10.21.110.222	10.21.110.223
120	10.21.110.224/27	10.21.110.225 – 10.21.110.254	10.21.110.255
121	10.21.111.0/27	10.21.111.1 – 10.21.111.30	10.21.111.31
122	10.21.111.32/27	10.21.111.33 – 10.21.111.62	10.21.111.63
123	10.21.111.64/27	10.21.111.65 – 10.21.111.94	10.21.111.95
124	10.21.111.96/27	10.21.111.97 – 10.21.111.126	10.21.111.127
125	10.21.111.128/27	10.21.111.129 – 10.21.111.158	10.21.111.159
126	10.21.111.160/27	10.21.111.161 – 10.21.111.190	10.21.111.191
127	10.21.111.192/27	10.21.111.193 – 10.21.111.222	10.21.111.223
128	10.21.111.224/27	10.21.111.225 – 10.21.111.254	10.21.111.255
129	10.21.112.0/27	10.21.112.1 – 10.21.112.30	10.21.112.31
130	10.21.112.32/27	10.21.112.33 – 10.21.112.62	10.21.112.63
131	10.21.112.64/27	10.21.112.65 – 10.21.112.94	10.21.112.95
132	10.21.112.96/27	10.21.112.97 – 10.21.112.126	10.21.112.127
133	10.21.112.128/27	10.21.112.129 – 10.21.112.158	10.21.112.159
134	10.21.112.160/27	10.21.112.161 – 10.21.112.190	10.21.112.191
135	10.21.112.192/27	10.21.112.193 – 10.21.112.222	10.21.112.223
136	10.21.112.224/27	10.21.112.225 – 10.21.112.254	10.21.112.255
137	10.21.113.0/27	10.21.113.1 – 10.21.113.30	10.21.113.31
138	10.21.113.32/27	10.21.113.33 – 10.21.113.62	10.21.113.63
139	10.21.113.64/27	10.21.113.65 – 10.21.113.94	10.21.113.95
140	10.21.113.96/27	10.21.113.97 – 10.21.113.126	10.21.113.127
141	10.21.113.128/27	10.21.113.129 – 10.21.113.158	10.21.113.159
142	10.21.113.160/27	10.21.113.161 – 10.21.113.190	10.21.113.191
143	10.21.113.192/27	10.21.113.193 – 10.21.113.222	10.21.113.223
144	10.21.113.224/27	10.21.113.225 – 10.21.113.254	10.21.113.255
145	10.21.114.0/27	10.21.114.1 – 10.21.114.30	10.21.114.31
146	10.21.114.32/27	10.21.114.33 – 10.21.114.62	10.21.114.63
147	10.21.114.64/27	10.21.114.65 – 10.21.114.94	10.21.114.95
148	10.21.114.96/27	10.21.114.97 – 10.21.114.126	10.21.114.127
149	10.21.114.128/27	10.21.114.129 – 10.21.114.158	10.21.114.159
150	10.21.114.160/27	10.21.114.161 – 10.21.114.190	10.21.114.191
151	10.21.114.192/27	10.21.114.193 – 10.21.114.222	10.21.114.223
152	10.21.114.224/27	10.21.114.225 – 10.21.114.254	10.21.114.255
153	10.21.115.0/27	10.21.115.1 – 10.21.115.30	10.21.115.31
154	10.21.115.32/27	10.21.115.33 – 10.21.115.62	10.21.115.63
155	10.21.115.64/27	10.21.115.65 – 10.21.115.94	10.21.115.95
156	10.21.115.96/27	10.21.115.97 – 10.21.115.126	10.21.115.127
157	10.21.115.128/27	10.21.115.129 – 10.21.115.158	10.21.115.159
158	10.21.115.160/27	10.21.115.161 – 10.21.115.190	10.21.115.191
159	10.21.115.192/27	10.21.115.193 – 10.21.115.222	10.21.115.223
160	10.21.115.224/27	10.21.115.225 – 10.21.115.254	10.21.115.255
161	10.21.116.0/27	10.21.116.1 – 10.21.116.30	10.21.116.31
162	10.21.116.32/27	10.21.116.33 – 10.21.116.62	10.21.116.63
163	10.21.116.64/27	10.21.116.65 – 10.21.116.94	10.21.116.95
164	10.21.116.96/27	10.21.116.97 – 10.21.116.126	10.21.116.127
165	10.21.116.128/27	10.21.116.129 – 10.21.116.158	10.21.116.159
166	10.21.116.160/27	10.21.116.161 – 10.21.116.190	10.21.116.191
167	10.21.116.192/27	10.21.116.193 – 10.21.116.222	10.21.116.223
168	10.21.116.224/27	10.21.116.225 – 10.21.116.254	10.21.116.255
169	10.21.117.0/27	10.21.117.1 – 10.21.117.30	10.21.117.31
170	10.21.117.32/27	10.21.117.33 – 10.21.117.62	10.21.117.63
171	10.21.117.64/27	10.21.117.65 – 10.21.117.94	10.21.117.95
172	10.21.117.96/27	10.21.117.97 – 10.21.117.126	10.21.117.127
173	10.21.117.128/27	10.21.117.129 – 10.21.117.158	10.21.117.159
174	10.21.117.160/27	10.21.117.161 – 10.21.117.190	10.21.117.191
175	10.21.117.192/27	10.21.117.193 – 10.21.117.222	10.21.117.223
176	10.21.117.224/27	10.21.117.225 – 10.21.117.254	10.21.117.255
177	10.21.118.0/27	10.21.118.1 – 10.21.118.30	10.21.118.31
178	10.21.118.32/27	10.21.118.33 – 10.21.118.62	10.21.118.63
179	10.21.118.64/27	10.21.118.65 – 10.21.118.94	10.21.118.95
180	10.21.118.96/27	10.21.118.97 – 10.21.118.126	10.21.118.127
181	10.21.118.128/27	10.21.118.129 – 10.21.118.158	10.21.118.159
182	10.21.118.160/27	10.21.118.161 – 10.21.118.190	10.21.118.191
183	10.21.118.192/27	10.21.118.193 – 10.21.118.222	10.21.118.223
184	10.21.118.224/27	10.21.118.225 – 10.21.118.254	10.21.118.255
185	10.21.119.0/27	10.21.119.1 – 10.21.119.30	10.21.119.31
186	10.21.119.32/27	10.21.119.33 – 10.21.119.62	10.21.119.63
187	10.21.119.64/27	10.21.119.65 – 10.21.119.94	10.21.119.95
188	10.21.119.96/27	10.21.119.97 – 10.21.119.126	10.21.119.127
189	10.21.119.128/27	10.21.119.129 – 10.21.119.158	10.21.119.159
190	10.21.119.160/27	10.21.119.161 – 10.21.119.190	10.21.119.191
191	10.21.119.192/27	10.21.119.193 – 10.21.119.222	10.21.119.223
192	10.21.119.224/27	10.21.119.225 – 10.21.119.254	10.21.119.255
193	10.21.120.0/27	10.21.120.1 – 10.21.120.30	10.21.120.31
194	10.21.120.32/27	10.21.120.33 – 10.21.120.62	10.21.120.63
195	10.21.120.64/27	10.21.120.65 – 10.21.120.94	10.21.120.95
196	10.21.120.96/27	10.21.120.97 – 10.21.120.126	10.21.120.127
197	10.21.120.128/27	10.21.120.129 – 10.21.120.158	10.21.120.159
198	10.21.120.160/27	10.21.120.161 – 10.21.120.190	10.21.120.191
199	10.21.120.192/27	10.21.120.193 – 10.21.120.222	10.21.120.223
200	10.21.120.224/27	10.21.120.225 – 10.21.120.254	10.21.120.255
201	10.21.121.0/27	10.21.121.1 – 10.21.121.30	10.21.121.31
202	10.21.121.32/27	10.21.121.33 – 10.21.121.62	10.21.121.63
203	10.21.121.64/27	10.21.121.65 – 10.21.121.94	10.21.121.95
204	10.21.121.96/27	10.21.121.97 – 10.21.121.126	10.21.121.127
205	10.21.121.128/27	10.21.121.129 – 10.21.121.158	10.21.121.159
206	10.21.121.160/27	10.21.121.161 – 10.21.121.190	10.21.121.191
207	10.21.121.192/27	10.21.121.193 – 10.21.121.222	10.21.121.223
208	10.21.121.224/27	10.21.121.225 – 10.21.121.254	10.21.121.255
209	10.21.122.0/27	10.21.122.1 – 10.21.122.30	10.21.122.31
210	10.21.122.32/27	10.21.122.33 – 10.21.122.62	10.21.122.63
211	10.21.122.64/27	10.21.122.65 – 10.21.122.94	10.21.122.95
212	10.21.122.96/27	10.21.122.97 – 10.21.122.126	10.21.122.127
213	10.21.122.128/27	10.21.122.129 – 10.21.122.158	10.21.122.159
214	10.21.122.160/27	10.21.122.161 – 10.21.122.190	10.21.122.191
215	10.21.122.192/27	10.21.122.193 – 10.21.122.222	10.21.122.223
216	10.21.122.224/27	10.21.122.225 – 10.21.122.254	10.21.122.255
217	10.21.123.0/27	10.21.123.1 – 10.21.123.30	10.21.123.31
218	10.21.123.32/27	10.21.123.33 – 10.21.123.62	10.21.123.63
219	10.21.123.64/27	10.21.123.65 – 10.21.123.94	10.21.123.95
220	10.21.123.96/27	10.21.123.97 – 10.21.123.126	10.21.123.127
221	10.21.123.128/27	10.21.123.129 – 10.21.123.158	10.21.123.159
222	10.21.123.160/27	10.21.123.161 – 10.21.123.190	10.21.123.191
223	10.21.123.192/27	10.21.123.193 – 10.21.123.222	10.21.123.223
224	10.21.123.224/27	10.21.123.225 – 10.21.123.254	10.21.123.255
225	10.21.124.0/27	10.21.124.1 – 10.21.124.30	10.21.124.31
226	10.21.124.32/27	10.21.124.33 – 10.21.124.62	10.21.124.63
227	10.21.124.64/27	10.21.124.65 – 10.21.124.94	10.21.124.95
228	10.21.124.96/27	10.21.124.97 – 10.21.124.126	10.21.124.127
229	10.21.124.128/27	10.21.124.129 – 10.21.124.158	10.21.124.159
230	10.21.124.160/27	10.21.124.161 – 10.21.124.190	10.21.124.191
231	10.21.124.192/27	10.21.124.193 – 10.21.124.222	10.21.124.223
232	10.21.124.224/27	10.21.124.225 – 10.21.124.254	10.21.124.255
233	10.21.125.0/27	10.21.125.1 – 10.21.125.30	10.21.125.31
234	10.21.125.32/27	10.21.125.33 – 10.21.125.62	10.21.125.63
235	10.21.125.64/27	10.21.125.65 – 10.21.125.94	10.21.125.95
236	10.21.125.96/27	10.21.125.97 – 10.21.125.126	10.21.125.127
237	10.21.125.128/27	10.21.125.129 – 10.21.125.158	10.21.125.159
238	10.21.125.160/27	10.21.125.161 – 10.21.125.190	10.21.125.191
239	10.21.125.192/27	10.21.125.193 – 10.21.125.222	10.21.125.223
240	10.21.125.224/27	10.21.125.225 – 10.21.125.254	10.21.125.255
241	10.21.126.0/27	10.21.126.1 – 10.21.126.30	10.21.126.31
242	10.21.126.32/27	10.21.126.33 – 10.21.126.62	10.21.126.63
243	10.21.126.64/27	10.21.126.65 – 10.21.126.94	10.21.126.95
244	10.21.126.96/27	10.21.126.97 – 10.21.126.126	10.21.126.127
245	10.21.126.128/27	10.21.126.129 – 10.21.126.158	10.21.126.159
246	10.21.126.160/27	10.21.126.161 – 10.21.126.190	10.21.126.191
247	10.21.126.192/27	10.21.126.193 – 10.21.126.222	10.21.126.223
248	10.21.126.224/27	10.21.126.225 – 10.21.126.254	10.21.126.255
249	10.21.127.0/27	10.21.127.1 – 10.21.127.30	10.21.127.31
250	10.21.127.32/27	10.21.127.33 – 10.21.127.62	10.21.127.63
251	10.21.127.64/27	10.21.127.65 – 10.21.127.94	10.21.127.95
252	10.21.127.96/27	10.21.127.97 – 10.21.127.126	10.21.127.127
253	10.21.127.128/27	10.21.127.129 – 10.21.127.158	10.21.127.159
254	10.21.127.160/27	10.21.127.161 – 10.21.127.190	10.21.127.191
255	10.21.127.192/27	10.21.127.193 – 10.21.127.222	10.21.127.223
256	10.21.127.224/27	10.21.127.225 – 10.21.127.254	10.21.127.255

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 /19
/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	1
/20	255.255.240.0	4,096	4,094	2 split →
/21	255.255.248.0	2,048	2,046	4 split →
/22	255.255.252.0	1,024	1,022	8 split →
/23	255.255.254.0	512	510	16 split →
/24	255.255.255.0	256	254	32 split →
/25	255.255.255.128	128	126	64 split →
/26	255.255.255.192	64	62	128 split →
/27	255.255.255.224	32	30	256 split →
/28	255.255.255.240	16	14	512 split →
/29	255.255.255.248	8	6	1,024 split →
/30	255.255.255.252	4	2	2,048 split →
/31	255.255.255.254	2	2	4,096 split →
/32	255.255.255.255	1	1	8,192 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 →