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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.

Network196.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
196.0.0.0
Broadcast address
196.255.255.255
First usable
196.0.0.1
Last usable
196.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
C (default /24)
As numbers
Hex C4000000 · Integer 3288334336 to 3305111551
Reverse DNS zone
196.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11000100..00000000.00000000.00000000196.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network11000100..00000000.00000000.00000000196.0.0.0
Broadcast11000100..11111111.11111111.11111111196.255.255.255
Split into smaller subnets/18

196.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1196.0.0.0/18196.0.0.1 to 196.0.63.254196.0.63.25516,382
2196.0.64.0/18196.0.64.1 to 196.0.127.254196.0.127.25516,382
3196.0.128.0/18196.0.128.1 to 196.0.191.254196.0.191.25516,382
4196.0.192.0/18196.0.192.1 to 196.0.255.254196.0.255.25516,382
5196.1.0.0/18196.1.0.1 to 196.1.63.254196.1.63.25516,382
6196.1.64.0/18196.1.64.1 to 196.1.127.254196.1.127.25516,382
7196.1.128.0/18196.1.128.1 to 196.1.191.254196.1.191.25516,382
8196.1.192.0/18196.1.192.1 to 196.1.255.254196.1.255.25516,382
9196.2.0.0/18196.2.0.1 to 196.2.63.254196.2.63.25516,382
10196.2.64.0/18196.2.64.1 to 196.2.127.254196.2.127.25516,382
11196.2.128.0/18196.2.128.1 to 196.2.191.254196.2.191.25516,382
12196.2.192.0/18196.2.192.1 to 196.2.255.254196.2.255.25516,382
13196.3.0.0/18196.3.0.1 to 196.3.63.254196.3.63.25516,382
14196.3.64.0/18196.3.64.1 to 196.3.127.254196.3.127.25516,382
15196.3.128.0/18196.3.128.1 to 196.3.191.254196.3.191.25516,382
16196.3.192.0/18196.3.192.1 to 196.3.255.254196.3.255.25516,382
17196.4.0.0/18196.4.0.1 to 196.4.63.254196.4.63.25516,382
18196.4.64.0/18196.4.64.1 to 196.4.127.254196.4.127.25516,382
19196.4.128.0/18196.4.128.1 to 196.4.191.254196.4.191.25516,382
20196.4.192.0/18196.4.192.1 to 196.4.255.254196.4.255.25516,382
21196.5.0.0/18196.5.0.1 to 196.5.63.254196.5.63.25516,382
22196.5.64.0/18196.5.64.1 to 196.5.127.254196.5.127.25516,382
23196.5.128.0/18196.5.128.1 to 196.5.191.254196.5.191.25516,382
24196.5.192.0/18196.5.192.1 to 196.5.255.254196.5.255.25516,382
25196.6.0.0/18196.6.0.1 to 196.6.63.254196.6.63.25516,382
26196.6.64.0/18196.6.64.1 to 196.6.127.254196.6.127.25516,382
27196.6.128.0/18196.6.128.1 to 196.6.191.254196.6.191.25516,382
28196.6.192.0/18196.6.192.1 to 196.6.255.254196.6.255.25516,382
29196.7.0.0/18196.7.0.1 to 196.7.63.254196.7.63.25516,382
30196.7.64.0/18196.7.64.1 to 196.7.127.254196.7.127.25516,382
31196.7.128.0/18196.7.128.1 to 196.7.191.254196.7.191.25516,382
32196.7.192.0/18196.7.192.1 to 196.7.255.254196.7.255.25516,382
33196.8.0.0/18196.8.0.1 to 196.8.63.254196.8.63.25516,382
34196.8.64.0/18196.8.64.1 to 196.8.127.254196.8.127.25516,382
35196.8.128.0/18196.8.128.1 to 196.8.191.254196.8.191.25516,382
36196.8.192.0/18196.8.192.1 to 196.8.255.254196.8.255.25516,382
37196.9.0.0/18196.9.0.1 to 196.9.63.254196.9.63.25516,382
38196.9.64.0/18196.9.64.1 to 196.9.127.254196.9.127.25516,382
39196.9.128.0/18196.9.128.1 to 196.9.191.254196.9.191.25516,382
40196.9.192.0/18196.9.192.1 to 196.9.255.254196.9.255.25516,382
41196.10.0.0/18196.10.0.1 to 196.10.63.254196.10.63.25516,382
42196.10.64.0/18196.10.64.1 to 196.10.127.254196.10.127.25516,382
43196.10.128.0/18196.10.128.1 to 196.10.191.254196.10.191.25516,382
44196.10.192.0/18196.10.192.1 to 196.10.255.254196.10.255.25516,382
45196.11.0.0/18196.11.0.1 to 196.11.63.254196.11.63.25516,382
46196.11.64.0/18196.11.64.1 to 196.11.127.254196.11.127.25516,382
47196.11.128.0/18196.11.128.1 to 196.11.191.254196.11.191.25516,382
48196.11.192.0/18196.11.192.1 to 196.11.255.254196.11.255.25516,382
49196.12.0.0/18196.12.0.1 to 196.12.63.254196.12.63.25516,382
50196.12.64.0/18196.12.64.1 to 196.12.127.254196.12.127.25516,382
51196.12.128.0/18196.12.128.1 to 196.12.191.254196.12.191.25516,382
52196.12.192.0/18196.12.192.1 to 196.12.255.254196.12.255.25516,382
53196.13.0.0/18196.13.0.1 to 196.13.63.254196.13.63.25516,382
54196.13.64.0/18196.13.64.1 to 196.13.127.254196.13.127.25516,382
55196.13.128.0/18196.13.128.1 to 196.13.191.254196.13.191.25516,382
56196.13.192.0/18196.13.192.1 to 196.13.255.254196.13.255.25516,382
57196.14.0.0/18196.14.0.1 to 196.14.63.254196.14.63.25516,382
58196.14.64.0/18196.14.64.1 to 196.14.127.254196.14.127.25516,382
59196.14.128.0/18196.14.128.1 to 196.14.191.254196.14.191.25516,382
60196.14.192.0/18196.14.192.1 to 196.14.255.254196.14.255.25516,382
61196.15.0.0/18196.15.0.1 to 196.15.63.254196.15.63.25516,382
62196.15.64.0/18196.15.64.1 to 196.15.127.254196.15.127.25516,382
63196.15.128.0/18196.15.128.1 to 196.15.191.254196.15.191.25516,382
64196.15.192.0/18196.15.192.1 to 196.15.255.254196.15.255.25516,382
65196.16.0.0/18196.16.0.1 to 196.16.63.254196.16.63.25516,382
66196.16.64.0/18196.16.64.1 to 196.16.127.254196.16.127.25516,382
67196.16.128.0/18196.16.128.1 to 196.16.191.254196.16.191.25516,382
68196.16.192.0/18196.16.192.1 to 196.16.255.254196.16.255.25516,382
69196.17.0.0/18196.17.0.1 to 196.17.63.254196.17.63.25516,382
70196.17.64.0/18196.17.64.1 to 196.17.127.254196.17.127.25516,382
71196.17.128.0/18196.17.128.1 to 196.17.191.254196.17.191.25516,382
72196.17.192.0/18196.17.192.1 to 196.17.255.254196.17.255.25516,382
73196.18.0.0/18196.18.0.1 to 196.18.63.254196.18.63.25516,382
74196.18.64.0/18196.18.64.1 to 196.18.127.254196.18.127.25516,382
75196.18.128.0/18196.18.128.1 to 196.18.191.254196.18.191.25516,382
76196.18.192.0/18196.18.192.1 to 196.18.255.254196.18.255.25516,382
77196.19.0.0/18196.19.0.1 to 196.19.63.254196.19.63.25516,382
78196.19.64.0/18196.19.64.1 to 196.19.127.254196.19.127.25516,382
79196.19.128.0/18196.19.128.1 to 196.19.191.254196.19.191.25516,382
80196.19.192.0/18196.19.192.1 to 196.19.255.254196.19.255.25516,382
81196.20.0.0/18196.20.0.1 to 196.20.63.254196.20.63.25516,382
82196.20.64.0/18196.20.64.1 to 196.20.127.254196.20.127.25516,382
83196.20.128.0/18196.20.128.1 to 196.20.191.254196.20.191.25516,382
84196.20.192.0/18196.20.192.1 to 196.20.255.254196.20.255.25516,382
85196.21.0.0/18196.21.0.1 to 196.21.63.254196.21.63.25516,382
86196.21.64.0/18196.21.64.1 to 196.21.127.254196.21.127.25516,382
87196.21.128.0/18196.21.128.1 to 196.21.191.254196.21.191.25516,382
88196.21.192.0/18196.21.192.1 to 196.21.255.254196.21.255.25516,382
89196.22.0.0/18196.22.0.1 to 196.22.63.254196.22.63.25516,382
90196.22.64.0/18196.22.64.1 to 196.22.127.254196.22.127.25516,382
91196.22.128.0/18196.22.128.1 to 196.22.191.254196.22.191.25516,382
92196.22.192.0/18196.22.192.1 to 196.22.255.254196.22.255.25516,382
93196.23.0.0/18196.23.0.1 to 196.23.63.254196.23.63.25516,382
94196.23.64.0/18196.23.64.1 to 196.23.127.254196.23.127.25516,382
95196.23.128.0/18196.23.128.1 to 196.23.191.254196.23.191.25516,382
96196.23.192.0/18196.23.192.1 to 196.23.255.254196.23.255.25516,382
97196.24.0.0/18196.24.0.1 to 196.24.63.254196.24.63.25516,382
98196.24.64.0/18196.24.64.1 to 196.24.127.254196.24.127.25516,382
99196.24.128.0/18196.24.128.1 to 196.24.191.254196.24.191.25516,382
100196.24.192.0/18196.24.192.1 to 196.24.255.254196.24.255.25516,382
101196.25.0.0/18196.25.0.1 to 196.25.63.254196.25.63.25516,382
102196.25.64.0/18196.25.64.1 to 196.25.127.254196.25.127.25516,382
103196.25.128.0/18196.25.128.1 to 196.25.191.254196.25.191.25516,382
104196.25.192.0/18196.25.192.1 to 196.25.255.254196.25.255.25516,382
105196.26.0.0/18196.26.0.1 to 196.26.63.254196.26.63.25516,382
106196.26.64.0/18196.26.64.1 to 196.26.127.254196.26.127.25516,382
107196.26.128.0/18196.26.128.1 to 196.26.191.254196.26.191.25516,382
108196.26.192.0/18196.26.192.1 to 196.26.255.254196.26.255.25516,382
109196.27.0.0/18196.27.0.1 to 196.27.63.254196.27.63.25516,382
110196.27.64.0/18196.27.64.1 to 196.27.127.254196.27.127.25516,382
111196.27.128.0/18196.27.128.1 to 196.27.191.254196.27.191.25516,382
112196.27.192.0/18196.27.192.1 to 196.27.255.254196.27.255.25516,382
113196.28.0.0/18196.28.0.1 to 196.28.63.254196.28.63.25516,382
114196.28.64.0/18196.28.64.1 to 196.28.127.254196.28.127.25516,382
115196.28.128.0/18196.28.128.1 to 196.28.191.254196.28.191.25516,382
116196.28.192.0/18196.28.192.1 to 196.28.255.254196.28.255.25516,382
117196.29.0.0/18196.29.0.1 to 196.29.63.254196.29.63.25516,382
118196.29.64.0/18196.29.64.1 to 196.29.127.254196.29.127.25516,382
119196.29.128.0/18196.29.128.1 to 196.29.191.254196.29.191.25516,382
120196.29.192.0/18196.29.192.1 to 196.29.255.254196.29.255.25516,382
121196.30.0.0/18196.30.0.1 to 196.30.63.254196.30.63.25516,382
122196.30.64.0/18196.30.64.1 to 196.30.127.254196.30.127.25516,382
123196.30.128.0/18196.30.128.1 to 196.30.191.254196.30.191.25516,382
124196.30.192.0/18196.30.192.1 to 196.30.255.254196.30.255.25516,382
125196.31.0.0/18196.31.0.1 to 196.31.63.254196.31.63.25516,382
126196.31.64.0/18196.31.64.1 to 196.31.127.254196.31.127.25516,382
127196.31.128.0/18196.31.128.1 to 196.31.191.254196.31.191.25516,382
128196.31.192.0/18196.31.192.1 to 196.31.255.254196.31.255.25516,382
129196.32.0.0/18196.32.0.1 to 196.32.63.254196.32.63.25516,382
130196.32.64.0/18196.32.64.1 to 196.32.127.254196.32.127.25516,382
131196.32.128.0/18196.32.128.1 to 196.32.191.254196.32.191.25516,382
132196.32.192.0/18196.32.192.1 to 196.32.255.254196.32.255.25516,382
133196.33.0.0/18196.33.0.1 to 196.33.63.254196.33.63.25516,382
134196.33.64.0/18196.33.64.1 to 196.33.127.254196.33.127.25516,382
135196.33.128.0/18196.33.128.1 to 196.33.191.254196.33.191.25516,382
136196.33.192.0/18196.33.192.1 to 196.33.255.254196.33.255.25516,382
137196.34.0.0/18196.34.0.1 to 196.34.63.254196.34.63.25516,382
138196.34.64.0/18196.34.64.1 to 196.34.127.254196.34.127.25516,382
139196.34.128.0/18196.34.128.1 to 196.34.191.254196.34.191.25516,382
140196.34.192.0/18196.34.192.1 to 196.34.255.254196.34.255.25516,382
141196.35.0.0/18196.35.0.1 to 196.35.63.254196.35.63.25516,382
142196.35.64.0/18196.35.64.1 to 196.35.127.254196.35.127.25516,382
143196.35.128.0/18196.35.128.1 to 196.35.191.254196.35.191.25516,382
144196.35.192.0/18196.35.192.1 to 196.35.255.254196.35.255.25516,382
145196.36.0.0/18196.36.0.1 to 196.36.63.254196.36.63.25516,382
146196.36.64.0/18196.36.64.1 to 196.36.127.254196.36.127.25516,382
147196.36.128.0/18196.36.128.1 to 196.36.191.254196.36.191.25516,382
148196.36.192.0/18196.36.192.1 to 196.36.255.254196.36.255.25516,382
149196.37.0.0/18196.37.0.1 to 196.37.63.254196.37.63.25516,382
150196.37.64.0/18196.37.64.1 to 196.37.127.254196.37.127.25516,382
151196.37.128.0/18196.37.128.1 to 196.37.191.254196.37.191.25516,382
152196.37.192.0/18196.37.192.1 to 196.37.255.254196.37.255.25516,382
153196.38.0.0/18196.38.0.1 to 196.38.63.254196.38.63.25516,382
154196.38.64.0/18196.38.64.1 to 196.38.127.254196.38.127.25516,382
155196.38.128.0/18196.38.128.1 to 196.38.191.254196.38.191.25516,382
156196.38.192.0/18196.38.192.1 to 196.38.255.254196.38.255.25516,382
157196.39.0.0/18196.39.0.1 to 196.39.63.254196.39.63.25516,382
158196.39.64.0/18196.39.64.1 to 196.39.127.254196.39.127.25516,382
159196.39.128.0/18196.39.128.1 to 196.39.191.254196.39.191.25516,382
160196.39.192.0/18196.39.192.1 to 196.39.255.254196.39.255.25516,382
161196.40.0.0/18196.40.0.1 to 196.40.63.254196.40.63.25516,382
162196.40.64.0/18196.40.64.1 to 196.40.127.254196.40.127.25516,382
163196.40.128.0/18196.40.128.1 to 196.40.191.254196.40.191.25516,382
164196.40.192.0/18196.40.192.1 to 196.40.255.254196.40.255.25516,382
165196.41.0.0/18196.41.0.1 to 196.41.63.254196.41.63.25516,382
166196.41.64.0/18196.41.64.1 to 196.41.127.254196.41.127.25516,382
167196.41.128.0/18196.41.128.1 to 196.41.191.254196.41.191.25516,382
168196.41.192.0/18196.41.192.1 to 196.41.255.254196.41.255.25516,382
169196.42.0.0/18196.42.0.1 to 196.42.63.254196.42.63.25516,382
170196.42.64.0/18196.42.64.1 to 196.42.127.254196.42.127.25516,382
171196.42.128.0/18196.42.128.1 to 196.42.191.254196.42.191.25516,382
172196.42.192.0/18196.42.192.1 to 196.42.255.254196.42.255.25516,382
173196.43.0.0/18196.43.0.1 to 196.43.63.254196.43.63.25516,382
174196.43.64.0/18196.43.64.1 to 196.43.127.254196.43.127.25516,382
175196.43.128.0/18196.43.128.1 to 196.43.191.254196.43.191.25516,382
176196.43.192.0/18196.43.192.1 to 196.43.255.254196.43.255.25516,382
177196.44.0.0/18196.44.0.1 to 196.44.63.254196.44.63.25516,382
178196.44.64.0/18196.44.64.1 to 196.44.127.254196.44.127.25516,382
179196.44.128.0/18196.44.128.1 to 196.44.191.254196.44.191.25516,382
180196.44.192.0/18196.44.192.1 to 196.44.255.254196.44.255.25516,382
181196.45.0.0/18196.45.0.1 to 196.45.63.254196.45.63.25516,382
182196.45.64.0/18196.45.64.1 to 196.45.127.254196.45.127.25516,382
183196.45.128.0/18196.45.128.1 to 196.45.191.254196.45.191.25516,382
184196.45.192.0/18196.45.192.1 to 196.45.255.254196.45.255.25516,382
185196.46.0.0/18196.46.0.1 to 196.46.63.254196.46.63.25516,382
186196.46.64.0/18196.46.64.1 to 196.46.127.254196.46.127.25516,382
187196.46.128.0/18196.46.128.1 to 196.46.191.254196.46.191.25516,382
188196.46.192.0/18196.46.192.1 to 196.46.255.254196.46.255.25516,382
189196.47.0.0/18196.47.0.1 to 196.47.63.254196.47.63.25516,382
190196.47.64.0/18196.47.64.1 to 196.47.127.254196.47.127.25516,382
191196.47.128.0/18196.47.128.1 to 196.47.191.254196.47.191.25516,382
192196.47.192.0/18196.47.192.1 to 196.47.255.254196.47.255.25516,382
193196.48.0.0/18196.48.0.1 to 196.48.63.254196.48.63.25516,382
194196.48.64.0/18196.48.64.1 to 196.48.127.254196.48.127.25516,382
195196.48.128.0/18196.48.128.1 to 196.48.191.254196.48.191.25516,382
196196.48.192.0/18196.48.192.1 to 196.48.255.254196.48.255.25516,382
197196.49.0.0/18196.49.0.1 to 196.49.63.254196.49.63.25516,382
198196.49.64.0/18196.49.64.1 to 196.49.127.254196.49.127.25516,382
199196.49.128.0/18196.49.128.1 to 196.49.191.254196.49.191.25516,382
200196.49.192.0/18196.49.192.1 to 196.49.255.254196.49.255.25516,382
201196.50.0.0/18196.50.0.1 to 196.50.63.254196.50.63.25516,382
202196.50.64.0/18196.50.64.1 to 196.50.127.254196.50.127.25516,382
203196.50.128.0/18196.50.128.1 to 196.50.191.254196.50.191.25516,382
204196.50.192.0/18196.50.192.1 to 196.50.255.254196.50.255.25516,382
205196.51.0.0/18196.51.0.1 to 196.51.63.254196.51.63.25516,382
206196.51.64.0/18196.51.64.1 to 196.51.127.254196.51.127.25516,382
207196.51.128.0/18196.51.128.1 to 196.51.191.254196.51.191.25516,382
208196.51.192.0/18196.51.192.1 to 196.51.255.254196.51.255.25516,382
209196.52.0.0/18196.52.0.1 to 196.52.63.254196.52.63.25516,382
210196.52.64.0/18196.52.64.1 to 196.52.127.254196.52.127.25516,382
211196.52.128.0/18196.52.128.1 to 196.52.191.254196.52.191.25516,382
212196.52.192.0/18196.52.192.1 to 196.52.255.254196.52.255.25516,382
213196.53.0.0/18196.53.0.1 to 196.53.63.254196.53.63.25516,382
214196.53.64.0/18196.53.64.1 to 196.53.127.254196.53.127.25516,382
215196.53.128.0/18196.53.128.1 to 196.53.191.254196.53.191.25516,382
216196.53.192.0/18196.53.192.1 to 196.53.255.254196.53.255.25516,382
217196.54.0.0/18196.54.0.1 to 196.54.63.254196.54.63.25516,382
218196.54.64.0/18196.54.64.1 to 196.54.127.254196.54.127.25516,382
219196.54.128.0/18196.54.128.1 to 196.54.191.254196.54.191.25516,382
220196.54.192.0/18196.54.192.1 to 196.54.255.254196.54.255.25516,382
221196.55.0.0/18196.55.0.1 to 196.55.63.254196.55.63.25516,382
222196.55.64.0/18196.55.64.1 to 196.55.127.254196.55.127.25516,382
223196.55.128.0/18196.55.128.1 to 196.55.191.254196.55.191.25516,382
224196.55.192.0/18196.55.192.1 to 196.55.255.254196.55.255.25516,382
225196.56.0.0/18196.56.0.1 to 196.56.63.254196.56.63.25516,382
226196.56.64.0/18196.56.64.1 to 196.56.127.254196.56.127.25516,382
227196.56.128.0/18196.56.128.1 to 196.56.191.254196.56.191.25516,382
228196.56.192.0/18196.56.192.1 to 196.56.255.254196.56.255.25516,382
229196.57.0.0/18196.57.0.1 to 196.57.63.254196.57.63.25516,382
230196.57.64.0/18196.57.64.1 to 196.57.127.254196.57.127.25516,382
231196.57.128.0/18196.57.128.1 to 196.57.191.254196.57.191.25516,382
232196.57.192.0/18196.57.192.1 to 196.57.255.254196.57.255.25516,382
233196.58.0.0/18196.58.0.1 to 196.58.63.254196.58.63.25516,382
234196.58.64.0/18196.58.64.1 to 196.58.127.254196.58.127.25516,382
235196.58.128.0/18196.58.128.1 to 196.58.191.254196.58.191.25516,382
236196.58.192.0/18196.58.192.1 to 196.58.255.254196.58.255.25516,382
237196.59.0.0/18196.59.0.1 to 196.59.63.254196.59.63.25516,382
238196.59.64.0/18196.59.64.1 to 196.59.127.254196.59.127.25516,382
239196.59.128.0/18196.59.128.1 to 196.59.191.254196.59.191.25516,382
240196.59.192.0/18196.59.192.1 to 196.59.255.254196.59.255.25516,382
241196.60.0.0/18196.60.0.1 to 196.60.63.254196.60.63.25516,382
242196.60.64.0/18196.60.64.1 to 196.60.127.254196.60.127.25516,382
243196.60.128.0/18196.60.128.1 to 196.60.191.254196.60.191.25516,382
244196.60.192.0/18196.60.192.1 to 196.60.255.254196.60.255.25516,382
245196.61.0.0/18196.61.0.1 to 196.61.63.254196.61.63.25516,382
246196.61.64.0/18196.61.64.1 to 196.61.127.254196.61.127.25516,382
247196.61.128.0/18196.61.128.1 to 196.61.191.254196.61.191.25516,382
248196.61.192.0/18196.61.192.1 to 196.61.255.254196.61.255.25516,382
249196.62.0.0/18196.62.0.1 to 196.62.63.254196.62.63.25516,382
250196.62.64.0/18196.62.64.1 to 196.62.127.254196.62.127.25516,382
251196.62.128.0/18196.62.128.1 to 196.62.191.254196.62.191.25516,382
252196.62.192.0/18196.62.192.1 to 196.62.255.254196.62.255.25516,382
253196.63.0.0/18196.63.0.1 to 196.63.63.254196.63.63.25516,382
254196.63.64.0/18196.63.64.1 to 196.63.127.254196.63.127.25516,382
255196.63.128.0/18196.63.128.1 to 196.63.191.254196.63.191.25516,382
256196.63.192.0/18196.63.192.1 to 196.63.255.254196.63.255.25516,382

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