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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.

Network196.0.0.0/6
Usable hosts67,108,862
Subnet mask252.0.0.0
Addresses67,108,864
Network address
196.0.0.0
Broadcast address
199.255.255.255
First usable
196.0.0.1
Last usable
199.255.255.254
Usable hosts
67,108,862 (67,108,864 less the network and broadcast addresses)
Subnet mask
252.0.0.0
Wildcard mask
3.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/6
Type
Public public
Old class
C (default /24)
As numbers
Hex C4000000 · Integer 3288334336 to 3355443199
Reverse DNS zones
196.in-addr.arpa
197.in-addr.arpa
198.in-addr.arpa
199.in-addr.arpa
/6 is not on a 8-bit boundary, so it takes 4 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11000100.00000000.00000000.00000000196.0.0.0
Subnet mask11111100.00000000.00000000.00000000252.0.0.0
Network11000100.00000000.00000000.00000000196.0.0.0
Broadcast11000111.11111111.11111111.11111111199.255.255.255
Split into smaller subnets/17

196.0.0.0/6 makes 2,048 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1196.0.0.0/17196.0.0.1 to 196.0.127.254196.0.127.25532,766
2196.0.128.0/17196.0.128.1 to 196.0.255.254196.0.255.25532,766
3196.1.0.0/17196.1.0.1 to 196.1.127.254196.1.127.25532,766
4196.1.128.0/17196.1.128.1 to 196.1.255.254196.1.255.25532,766
5196.2.0.0/17196.2.0.1 to 196.2.127.254196.2.127.25532,766
6196.2.128.0/17196.2.128.1 to 196.2.255.254196.2.255.25532,766
7196.3.0.0/17196.3.0.1 to 196.3.127.254196.3.127.25532,766
8196.3.128.0/17196.3.128.1 to 196.3.255.254196.3.255.25532,766
9196.4.0.0/17196.4.0.1 to 196.4.127.254196.4.127.25532,766
10196.4.128.0/17196.4.128.1 to 196.4.255.254196.4.255.25532,766
11196.5.0.0/17196.5.0.1 to 196.5.127.254196.5.127.25532,766
12196.5.128.0/17196.5.128.1 to 196.5.255.254196.5.255.25532,766
13196.6.0.0/17196.6.0.1 to 196.6.127.254196.6.127.25532,766
14196.6.128.0/17196.6.128.1 to 196.6.255.254196.6.255.25532,766
15196.7.0.0/17196.7.0.1 to 196.7.127.254196.7.127.25532,766
16196.7.128.0/17196.7.128.1 to 196.7.255.254196.7.255.25532,766
17196.8.0.0/17196.8.0.1 to 196.8.127.254196.8.127.25532,766
18196.8.128.0/17196.8.128.1 to 196.8.255.254196.8.255.25532,766
19196.9.0.0/17196.9.0.1 to 196.9.127.254196.9.127.25532,766
20196.9.128.0/17196.9.128.1 to 196.9.255.254196.9.255.25532,766
21196.10.0.0/17196.10.0.1 to 196.10.127.254196.10.127.25532,766
22196.10.128.0/17196.10.128.1 to 196.10.255.254196.10.255.25532,766
23196.11.0.0/17196.11.0.1 to 196.11.127.254196.11.127.25532,766
24196.11.128.0/17196.11.128.1 to 196.11.255.254196.11.255.25532,766
25196.12.0.0/17196.12.0.1 to 196.12.127.254196.12.127.25532,766
26196.12.128.0/17196.12.128.1 to 196.12.255.254196.12.255.25532,766
27196.13.0.0/17196.13.0.1 to 196.13.127.254196.13.127.25532,766
28196.13.128.0/17196.13.128.1 to 196.13.255.254196.13.255.25532,766
29196.14.0.0/17196.14.0.1 to 196.14.127.254196.14.127.25532,766
30196.14.128.0/17196.14.128.1 to 196.14.255.254196.14.255.25532,766
31196.15.0.0/17196.15.0.1 to 196.15.127.254196.15.127.25532,766
32196.15.128.0/17196.15.128.1 to 196.15.255.254196.15.255.25532,766
33196.16.0.0/17196.16.0.1 to 196.16.127.254196.16.127.25532,766
34196.16.128.0/17196.16.128.1 to 196.16.255.254196.16.255.25532,766
35196.17.0.0/17196.17.0.1 to 196.17.127.254196.17.127.25532,766
36196.17.128.0/17196.17.128.1 to 196.17.255.254196.17.255.25532,766
37196.18.0.0/17196.18.0.1 to 196.18.127.254196.18.127.25532,766
38196.18.128.0/17196.18.128.1 to 196.18.255.254196.18.255.25532,766
39196.19.0.0/17196.19.0.1 to 196.19.127.254196.19.127.25532,766
40196.19.128.0/17196.19.128.1 to 196.19.255.254196.19.255.25532,766
41196.20.0.0/17196.20.0.1 to 196.20.127.254196.20.127.25532,766
42196.20.128.0/17196.20.128.1 to 196.20.255.254196.20.255.25532,766
43196.21.0.0/17196.21.0.1 to 196.21.127.254196.21.127.25532,766
44196.21.128.0/17196.21.128.1 to 196.21.255.254196.21.255.25532,766
45196.22.0.0/17196.22.0.1 to 196.22.127.254196.22.127.25532,766
46196.22.128.0/17196.22.128.1 to 196.22.255.254196.22.255.25532,766
47196.23.0.0/17196.23.0.1 to 196.23.127.254196.23.127.25532,766
48196.23.128.0/17196.23.128.1 to 196.23.255.254196.23.255.25532,766
49196.24.0.0/17196.24.0.1 to 196.24.127.254196.24.127.25532,766
50196.24.128.0/17196.24.128.1 to 196.24.255.254196.24.255.25532,766
51196.25.0.0/17196.25.0.1 to 196.25.127.254196.25.127.25532,766
52196.25.128.0/17196.25.128.1 to 196.25.255.254196.25.255.25532,766
53196.26.0.0/17196.26.0.1 to 196.26.127.254196.26.127.25532,766
54196.26.128.0/17196.26.128.1 to 196.26.255.254196.26.255.25532,766
55196.27.0.0/17196.27.0.1 to 196.27.127.254196.27.127.25532,766
56196.27.128.0/17196.27.128.1 to 196.27.255.254196.27.255.25532,766
57196.28.0.0/17196.28.0.1 to 196.28.127.254196.28.127.25532,766
58196.28.128.0/17196.28.128.1 to 196.28.255.254196.28.255.25532,766
59196.29.0.0/17196.29.0.1 to 196.29.127.254196.29.127.25532,766
60196.29.128.0/17196.29.128.1 to 196.29.255.254196.29.255.25532,766
61196.30.0.0/17196.30.0.1 to 196.30.127.254196.30.127.25532,766
62196.30.128.0/17196.30.128.1 to 196.30.255.254196.30.255.25532,766
63196.31.0.0/17196.31.0.1 to 196.31.127.254196.31.127.25532,766
64196.31.128.0/17196.31.128.1 to 196.31.255.254196.31.255.25532,766
65196.32.0.0/17196.32.0.1 to 196.32.127.254196.32.127.25532,766
66196.32.128.0/17196.32.128.1 to 196.32.255.254196.32.255.25532,766
67196.33.0.0/17196.33.0.1 to 196.33.127.254196.33.127.25532,766
68196.33.128.0/17196.33.128.1 to 196.33.255.254196.33.255.25532,766
69196.34.0.0/17196.34.0.1 to 196.34.127.254196.34.127.25532,766
70196.34.128.0/17196.34.128.1 to 196.34.255.254196.34.255.25532,766
71196.35.0.0/17196.35.0.1 to 196.35.127.254196.35.127.25532,766
72196.35.128.0/17196.35.128.1 to 196.35.255.254196.35.255.25532,766
73196.36.0.0/17196.36.0.1 to 196.36.127.254196.36.127.25532,766
74196.36.128.0/17196.36.128.1 to 196.36.255.254196.36.255.25532,766
75196.37.0.0/17196.37.0.1 to 196.37.127.254196.37.127.25532,766
76196.37.128.0/17196.37.128.1 to 196.37.255.254196.37.255.25532,766
77196.38.0.0/17196.38.0.1 to 196.38.127.254196.38.127.25532,766
78196.38.128.0/17196.38.128.1 to 196.38.255.254196.38.255.25532,766
79196.39.0.0/17196.39.0.1 to 196.39.127.254196.39.127.25532,766
80196.39.128.0/17196.39.128.1 to 196.39.255.254196.39.255.25532,766
81196.40.0.0/17196.40.0.1 to 196.40.127.254196.40.127.25532,766
82196.40.128.0/17196.40.128.1 to 196.40.255.254196.40.255.25532,766
83196.41.0.0/17196.41.0.1 to 196.41.127.254196.41.127.25532,766
84196.41.128.0/17196.41.128.1 to 196.41.255.254196.41.255.25532,766
85196.42.0.0/17196.42.0.1 to 196.42.127.254196.42.127.25532,766
86196.42.128.0/17196.42.128.1 to 196.42.255.254196.42.255.25532,766
87196.43.0.0/17196.43.0.1 to 196.43.127.254196.43.127.25532,766
88196.43.128.0/17196.43.128.1 to 196.43.255.254196.43.255.25532,766
89196.44.0.0/17196.44.0.1 to 196.44.127.254196.44.127.25532,766
90196.44.128.0/17196.44.128.1 to 196.44.255.254196.44.255.25532,766
91196.45.0.0/17196.45.0.1 to 196.45.127.254196.45.127.25532,766
92196.45.128.0/17196.45.128.1 to 196.45.255.254196.45.255.25532,766
93196.46.0.0/17196.46.0.1 to 196.46.127.254196.46.127.25532,766
94196.46.128.0/17196.46.128.1 to 196.46.255.254196.46.255.25532,766
95196.47.0.0/17196.47.0.1 to 196.47.127.254196.47.127.25532,766
96196.47.128.0/17196.47.128.1 to 196.47.255.254196.47.255.25532,766
97196.48.0.0/17196.48.0.1 to 196.48.127.254196.48.127.25532,766
98196.48.128.0/17196.48.128.1 to 196.48.255.254196.48.255.25532,766
99196.49.0.0/17196.49.0.1 to 196.49.127.254196.49.127.25532,766
100196.49.128.0/17196.49.128.1 to 196.49.255.254196.49.255.25532,766
101196.50.0.0/17196.50.0.1 to 196.50.127.254196.50.127.25532,766
102196.50.128.0/17196.50.128.1 to 196.50.255.254196.50.255.25532,766
103196.51.0.0/17196.51.0.1 to 196.51.127.254196.51.127.25532,766
104196.51.128.0/17196.51.128.1 to 196.51.255.254196.51.255.25532,766
105196.52.0.0/17196.52.0.1 to 196.52.127.254196.52.127.25532,766
106196.52.128.0/17196.52.128.1 to 196.52.255.254196.52.255.25532,766
107196.53.0.0/17196.53.0.1 to 196.53.127.254196.53.127.25532,766
108196.53.128.0/17196.53.128.1 to 196.53.255.254196.53.255.25532,766
109196.54.0.0/17196.54.0.1 to 196.54.127.254196.54.127.25532,766
110196.54.128.0/17196.54.128.1 to 196.54.255.254196.54.255.25532,766
111196.55.0.0/17196.55.0.1 to 196.55.127.254196.55.127.25532,766
112196.55.128.0/17196.55.128.1 to 196.55.255.254196.55.255.25532,766
113196.56.0.0/17196.56.0.1 to 196.56.127.254196.56.127.25532,766
114196.56.128.0/17196.56.128.1 to 196.56.255.254196.56.255.25532,766
115196.57.0.0/17196.57.0.1 to 196.57.127.254196.57.127.25532,766
116196.57.128.0/17196.57.128.1 to 196.57.255.254196.57.255.25532,766
117196.58.0.0/17196.58.0.1 to 196.58.127.254196.58.127.25532,766
118196.58.128.0/17196.58.128.1 to 196.58.255.254196.58.255.25532,766
119196.59.0.0/17196.59.0.1 to 196.59.127.254196.59.127.25532,766
120196.59.128.0/17196.59.128.1 to 196.59.255.254196.59.255.25532,766
121196.60.0.0/17196.60.0.1 to 196.60.127.254196.60.127.25532,766
122196.60.128.0/17196.60.128.1 to 196.60.255.254196.60.255.25532,766
123196.61.0.0/17196.61.0.1 to 196.61.127.254196.61.127.25532,766
124196.61.128.0/17196.61.128.1 to 196.61.255.254196.61.255.25532,766
125196.62.0.0/17196.62.0.1 to 196.62.127.254196.62.127.25532,766
126196.62.128.0/17196.62.128.1 to 196.62.255.254196.62.255.25532,766
127196.63.0.0/17196.63.0.1 to 196.63.127.254196.63.127.25532,766
128196.63.128.0/17196.63.128.1 to 196.63.255.254196.63.255.25532,766
129196.64.0.0/17196.64.0.1 to 196.64.127.254196.64.127.25532,766
130196.64.128.0/17196.64.128.1 to 196.64.255.254196.64.255.25532,766
131196.65.0.0/17196.65.0.1 to 196.65.127.254196.65.127.25532,766
132196.65.128.0/17196.65.128.1 to 196.65.255.254196.65.255.25532,766
133196.66.0.0/17196.66.0.1 to 196.66.127.254196.66.127.25532,766
134196.66.128.0/17196.66.128.1 to 196.66.255.254196.66.255.25532,766
135196.67.0.0/17196.67.0.1 to 196.67.127.254196.67.127.25532,766
136196.67.128.0/17196.67.128.1 to 196.67.255.254196.67.255.25532,766
137196.68.0.0/17196.68.0.1 to 196.68.127.254196.68.127.25532,766
138196.68.128.0/17196.68.128.1 to 196.68.255.254196.68.255.25532,766
139196.69.0.0/17196.69.0.1 to 196.69.127.254196.69.127.25532,766
140196.69.128.0/17196.69.128.1 to 196.69.255.254196.69.255.25532,766
141196.70.0.0/17196.70.0.1 to 196.70.127.254196.70.127.25532,766
142196.70.128.0/17196.70.128.1 to 196.70.255.254196.70.255.25532,766
143196.71.0.0/17196.71.0.1 to 196.71.127.254196.71.127.25532,766
144196.71.128.0/17196.71.128.1 to 196.71.255.254196.71.255.25532,766
145196.72.0.0/17196.72.0.1 to 196.72.127.254196.72.127.25532,766
146196.72.128.0/17196.72.128.1 to 196.72.255.254196.72.255.25532,766
147196.73.0.0/17196.73.0.1 to 196.73.127.254196.73.127.25532,766
148196.73.128.0/17196.73.128.1 to 196.73.255.254196.73.255.25532,766
149196.74.0.0/17196.74.0.1 to 196.74.127.254196.74.127.25532,766
150196.74.128.0/17196.74.128.1 to 196.74.255.254196.74.255.25532,766
151196.75.0.0/17196.75.0.1 to 196.75.127.254196.75.127.25532,766
152196.75.128.0/17196.75.128.1 to 196.75.255.254196.75.255.25532,766
153196.76.0.0/17196.76.0.1 to 196.76.127.254196.76.127.25532,766
154196.76.128.0/17196.76.128.1 to 196.76.255.254196.76.255.25532,766
155196.77.0.0/17196.77.0.1 to 196.77.127.254196.77.127.25532,766
156196.77.128.0/17196.77.128.1 to 196.77.255.254196.77.255.25532,766
157196.78.0.0/17196.78.0.1 to 196.78.127.254196.78.127.25532,766
158196.78.128.0/17196.78.128.1 to 196.78.255.254196.78.255.25532,766
159196.79.0.0/17196.79.0.1 to 196.79.127.254196.79.127.25532,766
160196.79.128.0/17196.79.128.1 to 196.79.255.254196.79.255.25532,766
161196.80.0.0/17196.80.0.1 to 196.80.127.254196.80.127.25532,766
162196.80.128.0/17196.80.128.1 to 196.80.255.254196.80.255.25532,766
163196.81.0.0/17196.81.0.1 to 196.81.127.254196.81.127.25532,766
164196.81.128.0/17196.81.128.1 to 196.81.255.254196.81.255.25532,766
165196.82.0.0/17196.82.0.1 to 196.82.127.254196.82.127.25532,766
166196.82.128.0/17196.82.128.1 to 196.82.255.254196.82.255.25532,766
167196.83.0.0/17196.83.0.1 to 196.83.127.254196.83.127.25532,766
168196.83.128.0/17196.83.128.1 to 196.83.255.254196.83.255.25532,766
169196.84.0.0/17196.84.0.1 to 196.84.127.254196.84.127.25532,766
170196.84.128.0/17196.84.128.1 to 196.84.255.254196.84.255.25532,766
171196.85.0.0/17196.85.0.1 to 196.85.127.254196.85.127.25532,766
172196.85.128.0/17196.85.128.1 to 196.85.255.254196.85.255.25532,766
173196.86.0.0/17196.86.0.1 to 196.86.127.254196.86.127.25532,766
174196.86.128.0/17196.86.128.1 to 196.86.255.254196.86.255.25532,766
175196.87.0.0/17196.87.0.1 to 196.87.127.254196.87.127.25532,766
176196.87.128.0/17196.87.128.1 to 196.87.255.254196.87.255.25532,766
177196.88.0.0/17196.88.0.1 to 196.88.127.254196.88.127.25532,766
178196.88.128.0/17196.88.128.1 to 196.88.255.254196.88.255.25532,766
179196.89.0.0/17196.89.0.1 to 196.89.127.254196.89.127.25532,766
180196.89.128.0/17196.89.128.1 to 196.89.255.254196.89.255.25532,766
181196.90.0.0/17196.90.0.1 to 196.90.127.254196.90.127.25532,766
182196.90.128.0/17196.90.128.1 to 196.90.255.254196.90.255.25532,766
183196.91.0.0/17196.91.0.1 to 196.91.127.254196.91.127.25532,766
184196.91.128.0/17196.91.128.1 to 196.91.255.254196.91.255.25532,766
185196.92.0.0/17196.92.0.1 to 196.92.127.254196.92.127.25532,766
186196.92.128.0/17196.92.128.1 to 196.92.255.254196.92.255.25532,766
187196.93.0.0/17196.93.0.1 to 196.93.127.254196.93.127.25532,766
188196.93.128.0/17196.93.128.1 to 196.93.255.254196.93.255.25532,766
189196.94.0.0/17196.94.0.1 to 196.94.127.254196.94.127.25532,766
190196.94.128.0/17196.94.128.1 to 196.94.255.254196.94.255.25532,766
191196.95.0.0/17196.95.0.1 to 196.95.127.254196.95.127.25532,766
192196.95.128.0/17196.95.128.1 to 196.95.255.254196.95.255.25532,766
193196.96.0.0/17196.96.0.1 to 196.96.127.254196.96.127.25532,766
194196.96.128.0/17196.96.128.1 to 196.96.255.254196.96.255.25532,766
195196.97.0.0/17196.97.0.1 to 196.97.127.254196.97.127.25532,766
196196.97.128.0/17196.97.128.1 to 196.97.255.254196.97.255.25532,766
197196.98.0.0/17196.98.0.1 to 196.98.127.254196.98.127.25532,766
198196.98.128.0/17196.98.128.1 to 196.98.255.254196.98.255.25532,766
199196.99.0.0/17196.99.0.1 to 196.99.127.254196.99.127.25532,766
200196.99.128.0/17196.99.128.1 to 196.99.255.254196.99.255.25532,766
201196.100.0.0/17196.100.0.1 to 196.100.127.254196.100.127.25532,766
202196.100.128.0/17196.100.128.1 to 196.100.255.254196.100.255.25532,766
203196.101.0.0/17196.101.0.1 to 196.101.127.254196.101.127.25532,766
204196.101.128.0/17196.101.128.1 to 196.101.255.254196.101.255.25532,766
205196.102.0.0/17196.102.0.1 to 196.102.127.254196.102.127.25532,766
206196.102.128.0/17196.102.128.1 to 196.102.255.254196.102.255.25532,766
207196.103.0.0/17196.103.0.1 to 196.103.127.254196.103.127.25532,766
208196.103.128.0/17196.103.128.1 to 196.103.255.254196.103.255.25532,766
209196.104.0.0/17196.104.0.1 to 196.104.127.254196.104.127.25532,766
210196.104.128.0/17196.104.128.1 to 196.104.255.254196.104.255.25532,766
211196.105.0.0/17196.105.0.1 to 196.105.127.254196.105.127.25532,766
212196.105.128.0/17196.105.128.1 to 196.105.255.254196.105.255.25532,766
213196.106.0.0/17196.106.0.1 to 196.106.127.254196.106.127.25532,766
214196.106.128.0/17196.106.128.1 to 196.106.255.254196.106.255.25532,766
215196.107.0.0/17196.107.0.1 to 196.107.127.254196.107.127.25532,766
216196.107.128.0/17196.107.128.1 to 196.107.255.254196.107.255.25532,766
217196.108.0.0/17196.108.0.1 to 196.108.127.254196.108.127.25532,766
218196.108.128.0/17196.108.128.1 to 196.108.255.254196.108.255.25532,766
219196.109.0.0/17196.109.0.1 to 196.109.127.254196.109.127.25532,766
220196.109.128.0/17196.109.128.1 to 196.109.255.254196.109.255.25532,766
221196.110.0.0/17196.110.0.1 to 196.110.127.254196.110.127.25532,766
222196.110.128.0/17196.110.128.1 to 196.110.255.254196.110.255.25532,766
223196.111.0.0/17196.111.0.1 to 196.111.127.254196.111.127.25532,766
224196.111.128.0/17196.111.128.1 to 196.111.255.254196.111.255.25532,766
225196.112.0.0/17196.112.0.1 to 196.112.127.254196.112.127.25532,766
226196.112.128.0/17196.112.128.1 to 196.112.255.254196.112.255.25532,766
227196.113.0.0/17196.113.0.1 to 196.113.127.254196.113.127.25532,766
228196.113.128.0/17196.113.128.1 to 196.113.255.254196.113.255.25532,766
229196.114.0.0/17196.114.0.1 to 196.114.127.254196.114.127.25532,766
230196.114.128.0/17196.114.128.1 to 196.114.255.254196.114.255.25532,766
231196.115.0.0/17196.115.0.1 to 196.115.127.254196.115.127.25532,766
232196.115.128.0/17196.115.128.1 to 196.115.255.254196.115.255.25532,766
233196.116.0.0/17196.116.0.1 to 196.116.127.254196.116.127.25532,766
234196.116.128.0/17196.116.128.1 to 196.116.255.254196.116.255.25532,766
235196.117.0.0/17196.117.0.1 to 196.117.127.254196.117.127.25532,766
236196.117.128.0/17196.117.128.1 to 196.117.255.254196.117.255.25532,766
237196.118.0.0/17196.118.0.1 to 196.118.127.254196.118.127.25532,766
238196.118.128.0/17196.118.128.1 to 196.118.255.254196.118.255.25532,766
239196.119.0.0/17196.119.0.1 to 196.119.127.254196.119.127.25532,766
240196.119.128.0/17196.119.128.1 to 196.119.255.254196.119.255.25532,766
241196.120.0.0/17196.120.0.1 to 196.120.127.254196.120.127.25532,766
242196.120.128.0/17196.120.128.1 to 196.120.255.254196.120.255.25532,766
243196.121.0.0/17196.121.0.1 to 196.121.127.254196.121.127.25532,766
244196.121.128.0/17196.121.128.1 to 196.121.255.254196.121.255.25532,766
245196.122.0.0/17196.122.0.1 to 196.122.127.254196.122.127.25532,766
246196.122.128.0/17196.122.128.1 to 196.122.255.254196.122.255.25532,766
247196.123.0.0/17196.123.0.1 to 196.123.127.254196.123.127.25532,766
248196.123.128.0/17196.123.128.1 to 196.123.255.254196.123.255.25532,766
249196.124.0.0/17196.124.0.1 to 196.124.127.254196.124.127.25532,766
250196.124.128.0/17196.124.128.1 to 196.124.255.254196.124.255.25532,766
251196.125.0.0/17196.125.0.1 to 196.125.127.254196.125.127.25532,766
252196.125.128.0/17196.125.128.1 to 196.125.255.254196.125.255.25532,766
253196.126.0.0/17196.126.0.1 to 196.126.127.254196.126.127.25532,766
254196.126.128.0/17196.126.128.1 to 196.126.255.254196.126.255.25532,766
255196.127.0.0/17196.127.0.1 to 196.127.127.254196.127.127.25532,766
256196.127.128.0/17196.127.128.1 to 196.127.255.254196.127.255.25532,766

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