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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.

Network196.0.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
196.0.0.0
Broadcast address
196.31.255.255
First usable
196.0.0.1
Last usable
196.31.255.254
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
Public public
Old class
C (default /24)
As numbers
Hex C4000000 · Integer 3288334336 to 3290431487
Reverse DNS zones
0.196.in-addr.arpa
1.196.in-addr.arpa
2.196.in-addr.arpa
3.196.in-addr.arpa
4.196.in-addr.arpa
5.196.in-addr.arpa
6.196.in-addr.arpa
7.196.in-addr.arpa
8.196.in-addr.arpa
9.196.in-addr.arpa
10.196.in-addr.arpa
11.196.in-addr.arpa
12.196.in-addr.arpa
13.196.in-addr.arpa
14.196.in-addr.arpa
15.196.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
Address11000100.00000000.00000000.00000000196.0.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11000100.00000000.00000000.00000000196.0.0.0
Broadcast11000100.00011111.11111111.11111111196.31.255.255
Split into smaller subnets/21

196.0.0.0/11 makes 1,024 subnets of /21; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1196.0.0.0/21196.0.0.1 to 196.0.7.254196.0.7.2552,046
2196.0.8.0/21196.0.8.1 to 196.0.15.254196.0.15.2552,046
3196.0.16.0/21196.0.16.1 to 196.0.23.254196.0.23.2552,046
4196.0.24.0/21196.0.24.1 to 196.0.31.254196.0.31.2552,046
5196.0.32.0/21196.0.32.1 to 196.0.39.254196.0.39.2552,046
6196.0.40.0/21196.0.40.1 to 196.0.47.254196.0.47.2552,046
7196.0.48.0/21196.0.48.1 to 196.0.55.254196.0.55.2552,046
8196.0.56.0/21196.0.56.1 to 196.0.63.254196.0.63.2552,046
9196.0.64.0/21196.0.64.1 to 196.0.71.254196.0.71.2552,046
10196.0.72.0/21196.0.72.1 to 196.0.79.254196.0.79.2552,046
11196.0.80.0/21196.0.80.1 to 196.0.87.254196.0.87.2552,046
12196.0.88.0/21196.0.88.1 to 196.0.95.254196.0.95.2552,046
13196.0.96.0/21196.0.96.1 to 196.0.103.254196.0.103.2552,046
14196.0.104.0/21196.0.104.1 to 196.0.111.254196.0.111.2552,046
15196.0.112.0/21196.0.112.1 to 196.0.119.254196.0.119.2552,046
16196.0.120.0/21196.0.120.1 to 196.0.127.254196.0.127.2552,046
17196.0.128.0/21196.0.128.1 to 196.0.135.254196.0.135.2552,046
18196.0.136.0/21196.0.136.1 to 196.0.143.254196.0.143.2552,046
19196.0.144.0/21196.0.144.1 to 196.0.151.254196.0.151.2552,046
20196.0.152.0/21196.0.152.1 to 196.0.159.254196.0.159.2552,046
21196.0.160.0/21196.0.160.1 to 196.0.167.254196.0.167.2552,046
22196.0.168.0/21196.0.168.1 to 196.0.175.254196.0.175.2552,046
23196.0.176.0/21196.0.176.1 to 196.0.183.254196.0.183.2552,046
24196.0.184.0/21196.0.184.1 to 196.0.191.254196.0.191.2552,046
25196.0.192.0/21196.0.192.1 to 196.0.199.254196.0.199.2552,046
26196.0.200.0/21196.0.200.1 to 196.0.207.254196.0.207.2552,046
27196.0.208.0/21196.0.208.1 to 196.0.215.254196.0.215.2552,046
28196.0.216.0/21196.0.216.1 to 196.0.223.254196.0.223.2552,046
29196.0.224.0/21196.0.224.1 to 196.0.231.254196.0.231.2552,046
30196.0.232.0/21196.0.232.1 to 196.0.239.254196.0.239.2552,046
31196.0.240.0/21196.0.240.1 to 196.0.247.254196.0.247.2552,046
32196.0.248.0/21196.0.248.1 to 196.0.255.254196.0.255.2552,046
33196.1.0.0/21196.1.0.1 to 196.1.7.254196.1.7.2552,046
34196.1.8.0/21196.1.8.1 to 196.1.15.254196.1.15.2552,046
35196.1.16.0/21196.1.16.1 to 196.1.23.254196.1.23.2552,046
36196.1.24.0/21196.1.24.1 to 196.1.31.254196.1.31.2552,046
37196.1.32.0/21196.1.32.1 to 196.1.39.254196.1.39.2552,046
38196.1.40.0/21196.1.40.1 to 196.1.47.254196.1.47.2552,046
39196.1.48.0/21196.1.48.1 to 196.1.55.254196.1.55.2552,046
40196.1.56.0/21196.1.56.1 to 196.1.63.254196.1.63.2552,046
41196.1.64.0/21196.1.64.1 to 196.1.71.254196.1.71.2552,046
42196.1.72.0/21196.1.72.1 to 196.1.79.254196.1.79.2552,046
43196.1.80.0/21196.1.80.1 to 196.1.87.254196.1.87.2552,046
44196.1.88.0/21196.1.88.1 to 196.1.95.254196.1.95.2552,046
45196.1.96.0/21196.1.96.1 to 196.1.103.254196.1.103.2552,046
46196.1.104.0/21196.1.104.1 to 196.1.111.254196.1.111.2552,046
47196.1.112.0/21196.1.112.1 to 196.1.119.254196.1.119.2552,046
48196.1.120.0/21196.1.120.1 to 196.1.127.254196.1.127.2552,046
49196.1.128.0/21196.1.128.1 to 196.1.135.254196.1.135.2552,046
50196.1.136.0/21196.1.136.1 to 196.1.143.254196.1.143.2552,046
51196.1.144.0/21196.1.144.1 to 196.1.151.254196.1.151.2552,046
52196.1.152.0/21196.1.152.1 to 196.1.159.254196.1.159.2552,046
53196.1.160.0/21196.1.160.1 to 196.1.167.254196.1.167.2552,046
54196.1.168.0/21196.1.168.1 to 196.1.175.254196.1.175.2552,046
55196.1.176.0/21196.1.176.1 to 196.1.183.254196.1.183.2552,046
56196.1.184.0/21196.1.184.1 to 196.1.191.254196.1.191.2552,046
57196.1.192.0/21196.1.192.1 to 196.1.199.254196.1.199.2552,046
58196.1.200.0/21196.1.200.1 to 196.1.207.254196.1.207.2552,046
59196.1.208.0/21196.1.208.1 to 196.1.215.254196.1.215.2552,046
60196.1.216.0/21196.1.216.1 to 196.1.223.254196.1.223.2552,046
61196.1.224.0/21196.1.224.1 to 196.1.231.254196.1.231.2552,046
62196.1.232.0/21196.1.232.1 to 196.1.239.254196.1.239.2552,046
63196.1.240.0/21196.1.240.1 to 196.1.247.254196.1.247.2552,046
64196.1.248.0/21196.1.248.1 to 196.1.255.254196.1.255.2552,046
65196.2.0.0/21196.2.0.1 to 196.2.7.254196.2.7.2552,046
66196.2.8.0/21196.2.8.1 to 196.2.15.254196.2.15.2552,046
67196.2.16.0/21196.2.16.1 to 196.2.23.254196.2.23.2552,046
68196.2.24.0/21196.2.24.1 to 196.2.31.254196.2.31.2552,046
69196.2.32.0/21196.2.32.1 to 196.2.39.254196.2.39.2552,046
70196.2.40.0/21196.2.40.1 to 196.2.47.254196.2.47.2552,046
71196.2.48.0/21196.2.48.1 to 196.2.55.254196.2.55.2552,046
72196.2.56.0/21196.2.56.1 to 196.2.63.254196.2.63.2552,046
73196.2.64.0/21196.2.64.1 to 196.2.71.254196.2.71.2552,046
74196.2.72.0/21196.2.72.1 to 196.2.79.254196.2.79.2552,046
75196.2.80.0/21196.2.80.1 to 196.2.87.254196.2.87.2552,046
76196.2.88.0/21196.2.88.1 to 196.2.95.254196.2.95.2552,046
77196.2.96.0/21196.2.96.1 to 196.2.103.254196.2.103.2552,046
78196.2.104.0/21196.2.104.1 to 196.2.111.254196.2.111.2552,046
79196.2.112.0/21196.2.112.1 to 196.2.119.254196.2.119.2552,046
80196.2.120.0/21196.2.120.1 to 196.2.127.254196.2.127.2552,046
81196.2.128.0/21196.2.128.1 to 196.2.135.254196.2.135.2552,046
82196.2.136.0/21196.2.136.1 to 196.2.143.254196.2.143.2552,046
83196.2.144.0/21196.2.144.1 to 196.2.151.254196.2.151.2552,046
84196.2.152.0/21196.2.152.1 to 196.2.159.254196.2.159.2552,046
85196.2.160.0/21196.2.160.1 to 196.2.167.254196.2.167.2552,046
86196.2.168.0/21196.2.168.1 to 196.2.175.254196.2.175.2552,046
87196.2.176.0/21196.2.176.1 to 196.2.183.254196.2.183.2552,046
88196.2.184.0/21196.2.184.1 to 196.2.191.254196.2.191.2552,046
89196.2.192.0/21196.2.192.1 to 196.2.199.254196.2.199.2552,046
90196.2.200.0/21196.2.200.1 to 196.2.207.254196.2.207.2552,046
91196.2.208.0/21196.2.208.1 to 196.2.215.254196.2.215.2552,046
92196.2.216.0/21196.2.216.1 to 196.2.223.254196.2.223.2552,046
93196.2.224.0/21196.2.224.1 to 196.2.231.254196.2.231.2552,046
94196.2.232.0/21196.2.232.1 to 196.2.239.254196.2.239.2552,046
95196.2.240.0/21196.2.240.1 to 196.2.247.254196.2.247.2552,046
96196.2.248.0/21196.2.248.1 to 196.2.255.254196.2.255.2552,046
97196.3.0.0/21196.3.0.1 to 196.3.7.254196.3.7.2552,046
98196.3.8.0/21196.3.8.1 to 196.3.15.254196.3.15.2552,046
99196.3.16.0/21196.3.16.1 to 196.3.23.254196.3.23.2552,046
100196.3.24.0/21196.3.24.1 to 196.3.31.254196.3.31.2552,046
101196.3.32.0/21196.3.32.1 to 196.3.39.254196.3.39.2552,046
102196.3.40.0/21196.3.40.1 to 196.3.47.254196.3.47.2552,046
103196.3.48.0/21196.3.48.1 to 196.3.55.254196.3.55.2552,046
104196.3.56.0/21196.3.56.1 to 196.3.63.254196.3.63.2552,046
105196.3.64.0/21196.3.64.1 to 196.3.71.254196.3.71.2552,046
106196.3.72.0/21196.3.72.1 to 196.3.79.254196.3.79.2552,046
107196.3.80.0/21196.3.80.1 to 196.3.87.254196.3.87.2552,046
108196.3.88.0/21196.3.88.1 to 196.3.95.254196.3.95.2552,046
109196.3.96.0/21196.3.96.1 to 196.3.103.254196.3.103.2552,046
110196.3.104.0/21196.3.104.1 to 196.3.111.254196.3.111.2552,046
111196.3.112.0/21196.3.112.1 to 196.3.119.254196.3.119.2552,046
112196.3.120.0/21196.3.120.1 to 196.3.127.254196.3.127.2552,046
113196.3.128.0/21196.3.128.1 to 196.3.135.254196.3.135.2552,046
114196.3.136.0/21196.3.136.1 to 196.3.143.254196.3.143.2552,046
115196.3.144.0/21196.3.144.1 to 196.3.151.254196.3.151.2552,046
116196.3.152.0/21196.3.152.1 to 196.3.159.254196.3.159.2552,046
117196.3.160.0/21196.3.160.1 to 196.3.167.254196.3.167.2552,046
118196.3.168.0/21196.3.168.1 to 196.3.175.254196.3.175.2552,046
119196.3.176.0/21196.3.176.1 to 196.3.183.254196.3.183.2552,046
120196.3.184.0/21196.3.184.1 to 196.3.191.254196.3.191.2552,046
121196.3.192.0/21196.3.192.1 to 196.3.199.254196.3.199.2552,046
122196.3.200.0/21196.3.200.1 to 196.3.207.254196.3.207.2552,046
123196.3.208.0/21196.3.208.1 to 196.3.215.254196.3.215.2552,046
124196.3.216.0/21196.3.216.1 to 196.3.223.254196.3.223.2552,046
125196.3.224.0/21196.3.224.1 to 196.3.231.254196.3.231.2552,046
126196.3.232.0/21196.3.232.1 to 196.3.239.254196.3.239.2552,046
127196.3.240.0/21196.3.240.1 to 196.3.247.254196.3.247.2552,046
128196.3.248.0/21196.3.248.1 to 196.3.255.254196.3.255.2552,046
129196.4.0.0/21196.4.0.1 to 196.4.7.254196.4.7.2552,046
130196.4.8.0/21196.4.8.1 to 196.4.15.254196.4.15.2552,046
131196.4.16.0/21196.4.16.1 to 196.4.23.254196.4.23.2552,046
132196.4.24.0/21196.4.24.1 to 196.4.31.254196.4.31.2552,046
133196.4.32.0/21196.4.32.1 to 196.4.39.254196.4.39.2552,046
134196.4.40.0/21196.4.40.1 to 196.4.47.254196.4.47.2552,046
135196.4.48.0/21196.4.48.1 to 196.4.55.254196.4.55.2552,046
136196.4.56.0/21196.4.56.1 to 196.4.63.254196.4.63.2552,046
137196.4.64.0/21196.4.64.1 to 196.4.71.254196.4.71.2552,046
138196.4.72.0/21196.4.72.1 to 196.4.79.254196.4.79.2552,046
139196.4.80.0/21196.4.80.1 to 196.4.87.254196.4.87.2552,046
140196.4.88.0/21196.4.88.1 to 196.4.95.254196.4.95.2552,046
141196.4.96.0/21196.4.96.1 to 196.4.103.254196.4.103.2552,046
142196.4.104.0/21196.4.104.1 to 196.4.111.254196.4.111.2552,046
143196.4.112.0/21196.4.112.1 to 196.4.119.254196.4.119.2552,046
144196.4.120.0/21196.4.120.1 to 196.4.127.254196.4.127.2552,046
145196.4.128.0/21196.4.128.1 to 196.4.135.254196.4.135.2552,046
146196.4.136.0/21196.4.136.1 to 196.4.143.254196.4.143.2552,046
147196.4.144.0/21196.4.144.1 to 196.4.151.254196.4.151.2552,046
148196.4.152.0/21196.4.152.1 to 196.4.159.254196.4.159.2552,046
149196.4.160.0/21196.4.160.1 to 196.4.167.254196.4.167.2552,046
150196.4.168.0/21196.4.168.1 to 196.4.175.254196.4.175.2552,046
151196.4.176.0/21196.4.176.1 to 196.4.183.254196.4.183.2552,046
152196.4.184.0/21196.4.184.1 to 196.4.191.254196.4.191.2552,046
153196.4.192.0/21196.4.192.1 to 196.4.199.254196.4.199.2552,046
154196.4.200.0/21196.4.200.1 to 196.4.207.254196.4.207.2552,046
155196.4.208.0/21196.4.208.1 to 196.4.215.254196.4.215.2552,046
156196.4.216.0/21196.4.216.1 to 196.4.223.254196.4.223.2552,046
157196.4.224.0/21196.4.224.1 to 196.4.231.254196.4.231.2552,046
158196.4.232.0/21196.4.232.1 to 196.4.239.254196.4.239.2552,046
159196.4.240.0/21196.4.240.1 to 196.4.247.254196.4.247.2552,046
160196.4.248.0/21196.4.248.1 to 196.4.255.254196.4.255.2552,046
161196.5.0.0/21196.5.0.1 to 196.5.7.254196.5.7.2552,046
162196.5.8.0/21196.5.8.1 to 196.5.15.254196.5.15.2552,046
163196.5.16.0/21196.5.16.1 to 196.5.23.254196.5.23.2552,046
164196.5.24.0/21196.5.24.1 to 196.5.31.254196.5.31.2552,046
165196.5.32.0/21196.5.32.1 to 196.5.39.254196.5.39.2552,046
166196.5.40.0/21196.5.40.1 to 196.5.47.254196.5.47.2552,046
167196.5.48.0/21196.5.48.1 to 196.5.55.254196.5.55.2552,046
168196.5.56.0/21196.5.56.1 to 196.5.63.254196.5.63.2552,046
169196.5.64.0/21196.5.64.1 to 196.5.71.254196.5.71.2552,046
170196.5.72.0/21196.5.72.1 to 196.5.79.254196.5.79.2552,046
171196.5.80.0/21196.5.80.1 to 196.5.87.254196.5.87.2552,046
172196.5.88.0/21196.5.88.1 to 196.5.95.254196.5.95.2552,046
173196.5.96.0/21196.5.96.1 to 196.5.103.254196.5.103.2552,046
174196.5.104.0/21196.5.104.1 to 196.5.111.254196.5.111.2552,046
175196.5.112.0/21196.5.112.1 to 196.5.119.254196.5.119.2552,046
176196.5.120.0/21196.5.120.1 to 196.5.127.254196.5.127.2552,046
177196.5.128.0/21196.5.128.1 to 196.5.135.254196.5.135.2552,046
178196.5.136.0/21196.5.136.1 to 196.5.143.254196.5.143.2552,046
179196.5.144.0/21196.5.144.1 to 196.5.151.254196.5.151.2552,046
180196.5.152.0/21196.5.152.1 to 196.5.159.254196.5.159.2552,046
181196.5.160.0/21196.5.160.1 to 196.5.167.254196.5.167.2552,046
182196.5.168.0/21196.5.168.1 to 196.5.175.254196.5.175.2552,046
183196.5.176.0/21196.5.176.1 to 196.5.183.254196.5.183.2552,046
184196.5.184.0/21196.5.184.1 to 196.5.191.254196.5.191.2552,046
185196.5.192.0/21196.5.192.1 to 196.5.199.254196.5.199.2552,046
186196.5.200.0/21196.5.200.1 to 196.5.207.254196.5.207.2552,046
187196.5.208.0/21196.5.208.1 to 196.5.215.254196.5.215.2552,046
188196.5.216.0/21196.5.216.1 to 196.5.223.254196.5.223.2552,046
189196.5.224.0/21196.5.224.1 to 196.5.231.254196.5.231.2552,046
190196.5.232.0/21196.5.232.1 to 196.5.239.254196.5.239.2552,046
191196.5.240.0/21196.5.240.1 to 196.5.247.254196.5.247.2552,046
192196.5.248.0/21196.5.248.1 to 196.5.255.254196.5.255.2552,046
193196.6.0.0/21196.6.0.1 to 196.6.7.254196.6.7.2552,046
194196.6.8.0/21196.6.8.1 to 196.6.15.254196.6.15.2552,046
195196.6.16.0/21196.6.16.1 to 196.6.23.254196.6.23.2552,046
196196.6.24.0/21196.6.24.1 to 196.6.31.254196.6.31.2552,046
197196.6.32.0/21196.6.32.1 to 196.6.39.254196.6.39.2552,046
198196.6.40.0/21196.6.40.1 to 196.6.47.254196.6.47.2552,046
199196.6.48.0/21196.6.48.1 to 196.6.55.254196.6.55.2552,046
200196.6.56.0/21196.6.56.1 to 196.6.63.254196.6.63.2552,046
201196.6.64.0/21196.6.64.1 to 196.6.71.254196.6.71.2552,046
202196.6.72.0/21196.6.72.1 to 196.6.79.254196.6.79.2552,046
203196.6.80.0/21196.6.80.1 to 196.6.87.254196.6.87.2552,046
204196.6.88.0/21196.6.88.1 to 196.6.95.254196.6.95.2552,046
205196.6.96.0/21196.6.96.1 to 196.6.103.254196.6.103.2552,046
206196.6.104.0/21196.6.104.1 to 196.6.111.254196.6.111.2552,046
207196.6.112.0/21196.6.112.1 to 196.6.119.254196.6.119.2552,046
208196.6.120.0/21196.6.120.1 to 196.6.127.254196.6.127.2552,046
209196.6.128.0/21196.6.128.1 to 196.6.135.254196.6.135.2552,046
210196.6.136.0/21196.6.136.1 to 196.6.143.254196.6.143.2552,046
211196.6.144.0/21196.6.144.1 to 196.6.151.254196.6.151.2552,046
212196.6.152.0/21196.6.152.1 to 196.6.159.254196.6.159.2552,046
213196.6.160.0/21196.6.160.1 to 196.6.167.254196.6.167.2552,046
214196.6.168.0/21196.6.168.1 to 196.6.175.254196.6.175.2552,046
215196.6.176.0/21196.6.176.1 to 196.6.183.254196.6.183.2552,046
216196.6.184.0/21196.6.184.1 to 196.6.191.254196.6.191.2552,046
217196.6.192.0/21196.6.192.1 to 196.6.199.254196.6.199.2552,046
218196.6.200.0/21196.6.200.1 to 196.6.207.254196.6.207.2552,046
219196.6.208.0/21196.6.208.1 to 196.6.215.254196.6.215.2552,046
220196.6.216.0/21196.6.216.1 to 196.6.223.254196.6.223.2552,046
221196.6.224.0/21196.6.224.1 to 196.6.231.254196.6.231.2552,046
222196.6.232.0/21196.6.232.1 to 196.6.239.254196.6.239.2552,046
223196.6.240.0/21196.6.240.1 to 196.6.247.254196.6.247.2552,046
224196.6.248.0/21196.6.248.1 to 196.6.255.254196.6.255.2552,046
225196.7.0.0/21196.7.0.1 to 196.7.7.254196.7.7.2552,046
226196.7.8.0/21196.7.8.1 to 196.7.15.254196.7.15.2552,046
227196.7.16.0/21196.7.16.1 to 196.7.23.254196.7.23.2552,046
228196.7.24.0/21196.7.24.1 to 196.7.31.254196.7.31.2552,046
229196.7.32.0/21196.7.32.1 to 196.7.39.254196.7.39.2552,046
230196.7.40.0/21196.7.40.1 to 196.7.47.254196.7.47.2552,046
231196.7.48.0/21196.7.48.1 to 196.7.55.254196.7.55.2552,046
232196.7.56.0/21196.7.56.1 to 196.7.63.254196.7.63.2552,046
233196.7.64.0/21196.7.64.1 to 196.7.71.254196.7.71.2552,046
234196.7.72.0/21196.7.72.1 to 196.7.79.254196.7.79.2552,046
235196.7.80.0/21196.7.80.1 to 196.7.87.254196.7.87.2552,046
236196.7.88.0/21196.7.88.1 to 196.7.95.254196.7.95.2552,046
237196.7.96.0/21196.7.96.1 to 196.7.103.254196.7.103.2552,046
238196.7.104.0/21196.7.104.1 to 196.7.111.254196.7.111.2552,046
239196.7.112.0/21196.7.112.1 to 196.7.119.254196.7.119.2552,046
240196.7.120.0/21196.7.120.1 to 196.7.127.254196.7.127.2552,046
241196.7.128.0/21196.7.128.1 to 196.7.135.254196.7.135.2552,046
242196.7.136.0/21196.7.136.1 to 196.7.143.254196.7.143.2552,046
243196.7.144.0/21196.7.144.1 to 196.7.151.254196.7.151.2552,046
244196.7.152.0/21196.7.152.1 to 196.7.159.254196.7.159.2552,046
245196.7.160.0/21196.7.160.1 to 196.7.167.254196.7.167.2552,046
246196.7.168.0/21196.7.168.1 to 196.7.175.254196.7.175.2552,046
247196.7.176.0/21196.7.176.1 to 196.7.183.254196.7.183.2552,046
248196.7.184.0/21196.7.184.1 to 196.7.191.254196.7.191.2552,046
249196.7.192.0/21196.7.192.1 to 196.7.199.254196.7.199.2552,046
250196.7.200.0/21196.7.200.1 to 196.7.207.254196.7.207.2552,046
251196.7.208.0/21196.7.208.1 to 196.7.215.254196.7.215.2552,046
252196.7.216.0/21196.7.216.1 to 196.7.223.254196.7.223.2552,046
253196.7.224.0/21196.7.224.1 to 196.7.231.254196.7.231.2552,046
254196.7.232.0/21196.7.232.1 to 196.7.239.254196.7.239.2552,046
255196.7.240.0/21196.7.240.1 to 196.7.247.254196.7.247.2552,046
256196.7.248.0/21196.7.248.1 to 196.7.255.254196.7.255.2552,046

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