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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network246.64.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
246.64.0.0
Broadcast address
246.95.255.255
First usable
246.64.0.1
Last usable
246.95.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Reserved 240.0.0.0/4
Future use; not usable on most systems
Old class
E (reserved)
As numbers
Hex F6400000 · Integer 4131389440 to 4133486591
Reverse DNS zones
64.246.in-addr.arpa
65.246.in-addr.arpa
66.246.in-addr.arpa
67.246.in-addr.arpa
68.246.in-addr.arpa
69.246.in-addr.arpa
70.246.in-addr.arpa
71.246.in-addr.arpa
72.246.in-addr.arpa
73.246.in-addr.arpa
74.246.in-addr.arpa
75.246.in-addr.arpa
76.246.in-addr.arpa
77.246.in-addr.arpa
78.246.in-addr.arpa
79.246.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11110110.01000000.00000000.00000000246.64.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11110110.01000000.00000000.00000000246.64.0.0
Broadcast11110110.01011111.11111111.11111111246.95.255.255
Split into smaller subnets/19
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

246.64.0.0/11 makes 256 subnets of /19.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1246.64.0.0/19246.64.0.1 to 246.64.31.254246.64.31.2558,190
2246.64.32.0/19246.64.32.1 to 246.64.63.254246.64.63.2558,190
3246.64.64.0/19246.64.64.1 to 246.64.95.254246.64.95.2558,190
4246.64.96.0/19246.64.96.1 to 246.64.127.254246.64.127.2558,190
5246.64.128.0/19246.64.128.1 to 246.64.159.254246.64.159.2558,190
6246.64.160.0/19246.64.160.1 to 246.64.191.254246.64.191.2558,190
7246.64.192.0/19246.64.192.1 to 246.64.223.254246.64.223.2558,190
8246.64.224.0/19246.64.224.1 to 246.64.255.254246.64.255.2558,190
9246.65.0.0/19246.65.0.1 to 246.65.31.254246.65.31.2558,190
10246.65.32.0/19246.65.32.1 to 246.65.63.254246.65.63.2558,190
11246.65.64.0/19246.65.64.1 to 246.65.95.254246.65.95.2558,190
12246.65.96.0/19246.65.96.1 to 246.65.127.254246.65.127.2558,190
13246.65.128.0/19246.65.128.1 to 246.65.159.254246.65.159.2558,190
14246.65.160.0/19246.65.160.1 to 246.65.191.254246.65.191.2558,190
15246.65.192.0/19246.65.192.1 to 246.65.223.254246.65.223.2558,190
16246.65.224.0/19246.65.224.1 to 246.65.255.254246.65.255.2558,190
17246.66.0.0/19246.66.0.1 to 246.66.31.254246.66.31.2558,190
18246.66.32.0/19246.66.32.1 to 246.66.63.254246.66.63.2558,190
19246.66.64.0/19246.66.64.1 to 246.66.95.254246.66.95.2558,190
20246.66.96.0/19246.66.96.1 to 246.66.127.254246.66.127.2558,190
21246.66.128.0/19246.66.128.1 to 246.66.159.254246.66.159.2558,190
22246.66.160.0/19246.66.160.1 to 246.66.191.254246.66.191.2558,190
23246.66.192.0/19246.66.192.1 to 246.66.223.254246.66.223.2558,190
24246.66.224.0/19246.66.224.1 to 246.66.255.254246.66.255.2558,190
25246.67.0.0/19246.67.0.1 to 246.67.31.254246.67.31.2558,190
26246.67.32.0/19246.67.32.1 to 246.67.63.254246.67.63.2558,190
27246.67.64.0/19246.67.64.1 to 246.67.95.254246.67.95.2558,190
28246.67.96.0/19246.67.96.1 to 246.67.127.254246.67.127.2558,190
29246.67.128.0/19246.67.128.1 to 246.67.159.254246.67.159.2558,190
30246.67.160.0/19246.67.160.1 to 246.67.191.254246.67.191.2558,190
31246.67.192.0/19246.67.192.1 to 246.67.223.254246.67.223.2558,190
32246.67.224.0/19246.67.224.1 to 246.67.255.254246.67.255.2558,190
33246.68.0.0/19246.68.0.1 to 246.68.31.254246.68.31.2558,190
34246.68.32.0/19246.68.32.1 to 246.68.63.254246.68.63.2558,190
35246.68.64.0/19246.68.64.1 to 246.68.95.254246.68.95.2558,190
36246.68.96.0/19246.68.96.1 to 246.68.127.254246.68.127.2558,190
37246.68.128.0/19246.68.128.1 to 246.68.159.254246.68.159.2558,190
38246.68.160.0/19246.68.160.1 to 246.68.191.254246.68.191.2558,190
39246.68.192.0/19246.68.192.1 to 246.68.223.254246.68.223.2558,190
40246.68.224.0/19246.68.224.1 to 246.68.255.254246.68.255.2558,190
41246.69.0.0/19246.69.0.1 to 246.69.31.254246.69.31.2558,190
42246.69.32.0/19246.69.32.1 to 246.69.63.254246.69.63.2558,190
43246.69.64.0/19246.69.64.1 to 246.69.95.254246.69.95.2558,190
44246.69.96.0/19246.69.96.1 to 246.69.127.254246.69.127.2558,190
45246.69.128.0/19246.69.128.1 to 246.69.159.254246.69.159.2558,190
46246.69.160.0/19246.69.160.1 to 246.69.191.254246.69.191.2558,190
47246.69.192.0/19246.69.192.1 to 246.69.223.254246.69.223.2558,190
48246.69.224.0/19246.69.224.1 to 246.69.255.254246.69.255.2558,190
49246.70.0.0/19246.70.0.1 to 246.70.31.254246.70.31.2558,190
50246.70.32.0/19246.70.32.1 to 246.70.63.254246.70.63.2558,190
51246.70.64.0/19246.70.64.1 to 246.70.95.254246.70.95.2558,190
52246.70.96.0/19246.70.96.1 to 246.70.127.254246.70.127.2558,190
53246.70.128.0/19246.70.128.1 to 246.70.159.254246.70.159.2558,190
54246.70.160.0/19246.70.160.1 to 246.70.191.254246.70.191.2558,190
55246.70.192.0/19246.70.192.1 to 246.70.223.254246.70.223.2558,190
56246.70.224.0/19246.70.224.1 to 246.70.255.254246.70.255.2558,190
57246.71.0.0/19246.71.0.1 to 246.71.31.254246.71.31.2558,190
58246.71.32.0/19246.71.32.1 to 246.71.63.254246.71.63.2558,190
59246.71.64.0/19246.71.64.1 to 246.71.95.254246.71.95.2558,190
60246.71.96.0/19246.71.96.1 to 246.71.127.254246.71.127.2558,190
61246.71.128.0/19246.71.128.1 to 246.71.159.254246.71.159.2558,190
62246.71.160.0/19246.71.160.1 to 246.71.191.254246.71.191.2558,190
63246.71.192.0/19246.71.192.1 to 246.71.223.254246.71.223.2558,190
64246.71.224.0/19246.71.224.1 to 246.71.255.254246.71.255.2558,190
65246.72.0.0/19246.72.0.1 to 246.72.31.254246.72.31.2558,190
66246.72.32.0/19246.72.32.1 to 246.72.63.254246.72.63.2558,190
67246.72.64.0/19246.72.64.1 to 246.72.95.254246.72.95.2558,190
68246.72.96.0/19246.72.96.1 to 246.72.127.254246.72.127.2558,190
69246.72.128.0/19246.72.128.1 to 246.72.159.254246.72.159.2558,190
70246.72.160.0/19246.72.160.1 to 246.72.191.254246.72.191.2558,190
71246.72.192.0/19246.72.192.1 to 246.72.223.254246.72.223.2558,190
72246.72.224.0/19246.72.224.1 to 246.72.255.254246.72.255.2558,190
73246.73.0.0/19246.73.0.1 to 246.73.31.254246.73.31.2558,190
74246.73.32.0/19246.73.32.1 to 246.73.63.254246.73.63.2558,190
75246.73.64.0/19246.73.64.1 to 246.73.95.254246.73.95.2558,190
76246.73.96.0/19246.73.96.1 to 246.73.127.254246.73.127.2558,190
77246.73.128.0/19246.73.128.1 to 246.73.159.254246.73.159.2558,190
78246.73.160.0/19246.73.160.1 to 246.73.191.254246.73.191.2558,190
79246.73.192.0/19246.73.192.1 to 246.73.223.254246.73.223.2558,190
80246.73.224.0/19246.73.224.1 to 246.73.255.254246.73.255.2558,190
81246.74.0.0/19246.74.0.1 to 246.74.31.254246.74.31.2558,190
82246.74.32.0/19246.74.32.1 to 246.74.63.254246.74.63.2558,190
83246.74.64.0/19246.74.64.1 to 246.74.95.254246.74.95.2558,190
84246.74.96.0/19246.74.96.1 to 246.74.127.254246.74.127.2558,190
85246.74.128.0/19246.74.128.1 to 246.74.159.254246.74.159.2558,190
86246.74.160.0/19246.74.160.1 to 246.74.191.254246.74.191.2558,190
87246.74.192.0/19246.74.192.1 to 246.74.223.254246.74.223.2558,190
88246.74.224.0/19246.74.224.1 to 246.74.255.254246.74.255.2558,190
89246.75.0.0/19246.75.0.1 to 246.75.31.254246.75.31.2558,190
90246.75.32.0/19246.75.32.1 to 246.75.63.254246.75.63.2558,190
91246.75.64.0/19246.75.64.1 to 246.75.95.254246.75.95.2558,190
92246.75.96.0/19246.75.96.1 to 246.75.127.254246.75.127.2558,190
93246.75.128.0/19246.75.128.1 to 246.75.159.254246.75.159.2558,190
94246.75.160.0/19246.75.160.1 to 246.75.191.254246.75.191.2558,190
95246.75.192.0/19246.75.192.1 to 246.75.223.254246.75.223.2558,190
96246.75.224.0/19246.75.224.1 to 246.75.255.254246.75.255.2558,190
97246.76.0.0/19246.76.0.1 to 246.76.31.254246.76.31.2558,190
98246.76.32.0/19246.76.32.1 to 246.76.63.254246.76.63.2558,190
99246.76.64.0/19246.76.64.1 to 246.76.95.254246.76.95.2558,190
100246.76.96.0/19246.76.96.1 to 246.76.127.254246.76.127.2558,190
101246.76.128.0/19246.76.128.1 to 246.76.159.254246.76.159.2558,190
102246.76.160.0/19246.76.160.1 to 246.76.191.254246.76.191.2558,190
103246.76.192.0/19246.76.192.1 to 246.76.223.254246.76.223.2558,190
104246.76.224.0/19246.76.224.1 to 246.76.255.254246.76.255.2558,190
105246.77.0.0/19246.77.0.1 to 246.77.31.254246.77.31.2558,190
106246.77.32.0/19246.77.32.1 to 246.77.63.254246.77.63.2558,190
107246.77.64.0/19246.77.64.1 to 246.77.95.254246.77.95.2558,190
108246.77.96.0/19246.77.96.1 to 246.77.127.254246.77.127.2558,190
109246.77.128.0/19246.77.128.1 to 246.77.159.254246.77.159.2558,190
110246.77.160.0/19246.77.160.1 to 246.77.191.254246.77.191.2558,190
111246.77.192.0/19246.77.192.1 to 246.77.223.254246.77.223.2558,190
112246.77.224.0/19246.77.224.1 to 246.77.255.254246.77.255.2558,190
113246.78.0.0/19246.78.0.1 to 246.78.31.254246.78.31.2558,190
114246.78.32.0/19246.78.32.1 to 246.78.63.254246.78.63.2558,190
115246.78.64.0/19246.78.64.1 to 246.78.95.254246.78.95.2558,190
116246.78.96.0/19246.78.96.1 to 246.78.127.254246.78.127.2558,190
117246.78.128.0/19246.78.128.1 to 246.78.159.254246.78.159.2558,190
118246.78.160.0/19246.78.160.1 to 246.78.191.254246.78.191.2558,190
119246.78.192.0/19246.78.192.1 to 246.78.223.254246.78.223.2558,190
120246.78.224.0/19246.78.224.1 to 246.78.255.254246.78.255.2558,190
121246.79.0.0/19246.79.0.1 to 246.79.31.254246.79.31.2558,190
122246.79.32.0/19246.79.32.1 to 246.79.63.254246.79.63.2558,190
123246.79.64.0/19246.79.64.1 to 246.79.95.254246.79.95.2558,190
124246.79.96.0/19246.79.96.1 to 246.79.127.254246.79.127.2558,190
125246.79.128.0/19246.79.128.1 to 246.79.159.254246.79.159.2558,190
126246.79.160.0/19246.79.160.1 to 246.79.191.254246.79.191.2558,190
127246.79.192.0/19246.79.192.1 to 246.79.223.254246.79.223.2558,190
128246.79.224.0/19246.79.224.1 to 246.79.255.254246.79.255.2558,190
129246.80.0.0/19246.80.0.1 to 246.80.31.254246.80.31.2558,190
130246.80.32.0/19246.80.32.1 to 246.80.63.254246.80.63.2558,190
131246.80.64.0/19246.80.64.1 to 246.80.95.254246.80.95.2558,190
132246.80.96.0/19246.80.96.1 to 246.80.127.254246.80.127.2558,190
133246.80.128.0/19246.80.128.1 to 246.80.159.254246.80.159.2558,190
134246.80.160.0/19246.80.160.1 to 246.80.191.254246.80.191.2558,190
135246.80.192.0/19246.80.192.1 to 246.80.223.254246.80.223.2558,190
136246.80.224.0/19246.80.224.1 to 246.80.255.254246.80.255.2558,190
137246.81.0.0/19246.81.0.1 to 246.81.31.254246.81.31.2558,190
138246.81.32.0/19246.81.32.1 to 246.81.63.254246.81.63.2558,190
139246.81.64.0/19246.81.64.1 to 246.81.95.254246.81.95.2558,190
140246.81.96.0/19246.81.96.1 to 246.81.127.254246.81.127.2558,190
141246.81.128.0/19246.81.128.1 to 246.81.159.254246.81.159.2558,190
142246.81.160.0/19246.81.160.1 to 246.81.191.254246.81.191.2558,190
143246.81.192.0/19246.81.192.1 to 246.81.223.254246.81.223.2558,190
144246.81.224.0/19246.81.224.1 to 246.81.255.254246.81.255.2558,190
145246.82.0.0/19246.82.0.1 to 246.82.31.254246.82.31.2558,190
146246.82.32.0/19246.82.32.1 to 246.82.63.254246.82.63.2558,190
147246.82.64.0/19246.82.64.1 to 246.82.95.254246.82.95.2558,190
148246.82.96.0/19246.82.96.1 to 246.82.127.254246.82.127.2558,190
149246.82.128.0/19246.82.128.1 to 246.82.159.254246.82.159.2558,190
150246.82.160.0/19246.82.160.1 to 246.82.191.254246.82.191.2558,190
151246.82.192.0/19246.82.192.1 to 246.82.223.254246.82.223.2558,190
152246.82.224.0/19246.82.224.1 to 246.82.255.254246.82.255.2558,190
153246.83.0.0/19246.83.0.1 to 246.83.31.254246.83.31.2558,190
154246.83.32.0/19246.83.32.1 to 246.83.63.254246.83.63.2558,190
155246.83.64.0/19246.83.64.1 to 246.83.95.254246.83.95.2558,190
156246.83.96.0/19246.83.96.1 to 246.83.127.254246.83.127.2558,190
157246.83.128.0/19246.83.128.1 to 246.83.159.254246.83.159.2558,190
158246.83.160.0/19246.83.160.1 to 246.83.191.254246.83.191.2558,190
159246.83.192.0/19246.83.192.1 to 246.83.223.254246.83.223.2558,190
160246.83.224.0/19246.83.224.1 to 246.83.255.254246.83.255.2558,190
161246.84.0.0/19246.84.0.1 to 246.84.31.254246.84.31.2558,190
162246.84.32.0/19246.84.32.1 to 246.84.63.254246.84.63.2558,190
163246.84.64.0/19246.84.64.1 to 246.84.95.254246.84.95.2558,190
164246.84.96.0/19246.84.96.1 to 246.84.127.254246.84.127.2558,190
165246.84.128.0/19246.84.128.1 to 246.84.159.254246.84.159.2558,190
166246.84.160.0/19246.84.160.1 to 246.84.191.254246.84.191.2558,190
167246.84.192.0/19246.84.192.1 to 246.84.223.254246.84.223.2558,190
168246.84.224.0/19246.84.224.1 to 246.84.255.254246.84.255.2558,190
169246.85.0.0/19246.85.0.1 to 246.85.31.254246.85.31.2558,190
170246.85.32.0/19246.85.32.1 to 246.85.63.254246.85.63.2558,190
171246.85.64.0/19246.85.64.1 to 246.85.95.254246.85.95.2558,190
172246.85.96.0/19246.85.96.1 to 246.85.127.254246.85.127.2558,190
173246.85.128.0/19246.85.128.1 to 246.85.159.254246.85.159.2558,190
174246.85.160.0/19246.85.160.1 to 246.85.191.254246.85.191.2558,190
175246.85.192.0/19246.85.192.1 to 246.85.223.254246.85.223.2558,190
176246.85.224.0/19246.85.224.1 to 246.85.255.254246.85.255.2558,190
177246.86.0.0/19246.86.0.1 to 246.86.31.254246.86.31.2558,190
178246.86.32.0/19246.86.32.1 to 246.86.63.254246.86.63.2558,190
179246.86.64.0/19246.86.64.1 to 246.86.95.254246.86.95.2558,190
180246.86.96.0/19246.86.96.1 to 246.86.127.254246.86.127.2558,190
181246.86.128.0/19246.86.128.1 to 246.86.159.254246.86.159.2558,190
182246.86.160.0/19246.86.160.1 to 246.86.191.254246.86.191.2558,190
183246.86.192.0/19246.86.192.1 to 246.86.223.254246.86.223.2558,190
184246.86.224.0/19246.86.224.1 to 246.86.255.254246.86.255.2558,190
185246.87.0.0/19246.87.0.1 to 246.87.31.254246.87.31.2558,190
186246.87.32.0/19246.87.32.1 to 246.87.63.254246.87.63.2558,190
187246.87.64.0/19246.87.64.1 to 246.87.95.254246.87.95.2558,190
188246.87.96.0/19246.87.96.1 to 246.87.127.254246.87.127.2558,190
189246.87.128.0/19246.87.128.1 to 246.87.159.254246.87.159.2558,190
190246.87.160.0/19246.87.160.1 to 246.87.191.254246.87.191.2558,190
191246.87.192.0/19246.87.192.1 to 246.87.223.254246.87.223.2558,190
192246.87.224.0/19246.87.224.1 to 246.87.255.254246.87.255.2558,190
193246.88.0.0/19246.88.0.1 to 246.88.31.254246.88.31.2558,190
194246.88.32.0/19246.88.32.1 to 246.88.63.254246.88.63.2558,190
195246.88.64.0/19246.88.64.1 to 246.88.95.254246.88.95.2558,190
196246.88.96.0/19246.88.96.1 to 246.88.127.254246.88.127.2558,190
197246.88.128.0/19246.88.128.1 to 246.88.159.254246.88.159.2558,190
198246.88.160.0/19246.88.160.1 to 246.88.191.254246.88.191.2558,190
199246.88.192.0/19246.88.192.1 to 246.88.223.254246.88.223.2558,190
200246.88.224.0/19246.88.224.1 to 246.88.255.254246.88.255.2558,190
201246.89.0.0/19246.89.0.1 to 246.89.31.254246.89.31.2558,190
202246.89.32.0/19246.89.32.1 to 246.89.63.254246.89.63.2558,190
203246.89.64.0/19246.89.64.1 to 246.89.95.254246.89.95.2558,190
204246.89.96.0/19246.89.96.1 to 246.89.127.254246.89.127.2558,190
205246.89.128.0/19246.89.128.1 to 246.89.159.254246.89.159.2558,190
206246.89.160.0/19246.89.160.1 to 246.89.191.254246.89.191.2558,190
207246.89.192.0/19246.89.192.1 to 246.89.223.254246.89.223.2558,190
208246.89.224.0/19246.89.224.1 to 246.89.255.254246.89.255.2558,190
209246.90.0.0/19246.90.0.1 to 246.90.31.254246.90.31.2558,190
210246.90.32.0/19246.90.32.1 to 246.90.63.254246.90.63.2558,190
211246.90.64.0/19246.90.64.1 to 246.90.95.254246.90.95.2558,190
212246.90.96.0/19246.90.96.1 to 246.90.127.254246.90.127.2558,190
213246.90.128.0/19246.90.128.1 to 246.90.159.254246.90.159.2558,190
214246.90.160.0/19246.90.160.1 to 246.90.191.254246.90.191.2558,190
215246.90.192.0/19246.90.192.1 to 246.90.223.254246.90.223.2558,190
216246.90.224.0/19246.90.224.1 to 246.90.255.254246.90.255.2558,190
217246.91.0.0/19246.91.0.1 to 246.91.31.254246.91.31.2558,190
218246.91.32.0/19246.91.32.1 to 246.91.63.254246.91.63.2558,190
219246.91.64.0/19246.91.64.1 to 246.91.95.254246.91.95.2558,190
220246.91.96.0/19246.91.96.1 to 246.91.127.254246.91.127.2558,190
221246.91.128.0/19246.91.128.1 to 246.91.159.254246.91.159.2558,190
222246.91.160.0/19246.91.160.1 to 246.91.191.254246.91.191.2558,190
223246.91.192.0/19246.91.192.1 to 246.91.223.254246.91.223.2558,190
224246.91.224.0/19246.91.224.1 to 246.91.255.254246.91.255.2558,190
225246.92.0.0/19246.92.0.1 to 246.92.31.254246.92.31.2558,190
226246.92.32.0/19246.92.32.1 to 246.92.63.254246.92.63.2558,190
227246.92.64.0/19246.92.64.1 to 246.92.95.254246.92.95.2558,190
228246.92.96.0/19246.92.96.1 to 246.92.127.254246.92.127.2558,190
229246.92.128.0/19246.92.128.1 to 246.92.159.254246.92.159.2558,190
230246.92.160.0/19246.92.160.1 to 246.92.191.254246.92.191.2558,190
231246.92.192.0/19246.92.192.1 to 246.92.223.254246.92.223.2558,190
232246.92.224.0/19246.92.224.1 to 246.92.255.254246.92.255.2558,190
233246.93.0.0/19246.93.0.1 to 246.93.31.254246.93.31.2558,190
234246.93.32.0/19246.93.32.1 to 246.93.63.254246.93.63.2558,190
235246.93.64.0/19246.93.64.1 to 246.93.95.254246.93.95.2558,190
236246.93.96.0/19246.93.96.1 to 246.93.127.254246.93.127.2558,190
237246.93.128.0/19246.93.128.1 to 246.93.159.254246.93.159.2558,190
238246.93.160.0/19246.93.160.1 to 246.93.191.254246.93.191.2558,190
239246.93.192.0/19246.93.192.1 to 246.93.223.254246.93.223.2558,190
240246.93.224.0/19246.93.224.1 to 246.93.255.254246.93.255.2558,190
241246.94.0.0/19246.94.0.1 to 246.94.31.254246.94.31.2558,190
242246.94.32.0/19246.94.32.1 to 246.94.63.254246.94.63.2558,190
243246.94.64.0/19246.94.64.1 to 246.94.95.254246.94.95.2558,190
244246.94.96.0/19246.94.96.1 to 246.94.127.254246.94.127.2558,190
245246.94.128.0/19246.94.128.1 to 246.94.159.254246.94.159.2558,190
246246.94.160.0/19246.94.160.1 to 246.94.191.254246.94.191.2558,190
247246.94.192.0/19246.94.192.1 to 246.94.223.254246.94.223.2558,190
248246.94.224.0/19246.94.224.1 to 246.94.255.254246.94.255.2558,190
249246.95.0.0/19246.95.0.1 to 246.95.31.254246.95.31.2558,190
250246.95.32.0/19246.95.32.1 to 246.95.63.254246.95.63.2558,190
251246.95.64.0/19246.95.64.1 to 246.95.95.254246.95.95.2558,190
252246.95.96.0/19246.95.96.1 to 246.95.127.254246.95.127.2558,190
253246.95.128.0/19246.95.128.1 to 246.95.159.254246.95.159.2558,190
254246.95.160.0/19246.95.160.1 to 246.95.191.254246.95.191.2558,190
255246.95.192.0/19246.95.192.1 to 246.95.223.254246.95.223.2558,190
256246.95.224.0/19246.95.224.1 to 246.95.255.254246.95.255.2558,190

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.