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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.

Network214.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
214.0.0.0
Broadcast address
214.255.255.255
First usable
214.0.0.1
Last usable
214.255.255.254
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 D6000000 · Integer 3590324224 to 3607101439
Reverse DNS zone
214.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11010110..00000000.00000000.00000000214.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network11010110..00000000.00000000.00000000214.0.0.0
Broadcast11010110..11111111.11111111.11111111214.255.255.255
Split into smaller subnets/17
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

214.0.0.0/8 makes 512 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1214.0.0.0/17214.0.0.1 to 214.0.127.254214.0.127.25532,766
2214.0.128.0/17214.0.128.1 to 214.0.255.254214.0.255.25532,766
3214.1.0.0/17214.1.0.1 to 214.1.127.254214.1.127.25532,766
4214.1.128.0/17214.1.128.1 to 214.1.255.254214.1.255.25532,766
5214.2.0.0/17214.2.0.1 to 214.2.127.254214.2.127.25532,766
6214.2.128.0/17214.2.128.1 to 214.2.255.254214.2.255.25532,766
7214.3.0.0/17214.3.0.1 to 214.3.127.254214.3.127.25532,766
8214.3.128.0/17214.3.128.1 to 214.3.255.254214.3.255.25532,766
9214.4.0.0/17214.4.0.1 to 214.4.127.254214.4.127.25532,766
10214.4.128.0/17214.4.128.1 to 214.4.255.254214.4.255.25532,766
11214.5.0.0/17214.5.0.1 to 214.5.127.254214.5.127.25532,766
12214.5.128.0/17214.5.128.1 to 214.5.255.254214.5.255.25532,766
13214.6.0.0/17214.6.0.1 to 214.6.127.254214.6.127.25532,766
14214.6.128.0/17214.6.128.1 to 214.6.255.254214.6.255.25532,766
15214.7.0.0/17214.7.0.1 to 214.7.127.254214.7.127.25532,766
16214.7.128.0/17214.7.128.1 to 214.7.255.254214.7.255.25532,766
17214.8.0.0/17214.8.0.1 to 214.8.127.254214.8.127.25532,766
18214.8.128.0/17214.8.128.1 to 214.8.255.254214.8.255.25532,766
19214.9.0.0/17214.9.0.1 to 214.9.127.254214.9.127.25532,766
20214.9.128.0/17214.9.128.1 to 214.9.255.254214.9.255.25532,766
21214.10.0.0/17214.10.0.1 to 214.10.127.254214.10.127.25532,766
22214.10.128.0/17214.10.128.1 to 214.10.255.254214.10.255.25532,766
23214.11.0.0/17214.11.0.1 to 214.11.127.254214.11.127.25532,766
24214.11.128.0/17214.11.128.1 to 214.11.255.254214.11.255.25532,766
25214.12.0.0/17214.12.0.1 to 214.12.127.254214.12.127.25532,766
26214.12.128.0/17214.12.128.1 to 214.12.255.254214.12.255.25532,766
27214.13.0.0/17214.13.0.1 to 214.13.127.254214.13.127.25532,766
28214.13.128.0/17214.13.128.1 to 214.13.255.254214.13.255.25532,766
29214.14.0.0/17214.14.0.1 to 214.14.127.254214.14.127.25532,766
30214.14.128.0/17214.14.128.1 to 214.14.255.254214.14.255.25532,766
31214.15.0.0/17214.15.0.1 to 214.15.127.254214.15.127.25532,766
32214.15.128.0/17214.15.128.1 to 214.15.255.254214.15.255.25532,766
33214.16.0.0/17214.16.0.1 to 214.16.127.254214.16.127.25532,766
34214.16.128.0/17214.16.128.1 to 214.16.255.254214.16.255.25532,766
35214.17.0.0/17214.17.0.1 to 214.17.127.254214.17.127.25532,766
36214.17.128.0/17214.17.128.1 to 214.17.255.254214.17.255.25532,766
37214.18.0.0/17214.18.0.1 to 214.18.127.254214.18.127.25532,766
38214.18.128.0/17214.18.128.1 to 214.18.255.254214.18.255.25532,766
39214.19.0.0/17214.19.0.1 to 214.19.127.254214.19.127.25532,766
40214.19.128.0/17214.19.128.1 to 214.19.255.254214.19.255.25532,766
41214.20.0.0/17214.20.0.1 to 214.20.127.254214.20.127.25532,766
42214.20.128.0/17214.20.128.1 to 214.20.255.254214.20.255.25532,766
43214.21.0.0/17214.21.0.1 to 214.21.127.254214.21.127.25532,766
44214.21.128.0/17214.21.128.1 to 214.21.255.254214.21.255.25532,766
45214.22.0.0/17214.22.0.1 to 214.22.127.254214.22.127.25532,766
46214.22.128.0/17214.22.128.1 to 214.22.255.254214.22.255.25532,766
47214.23.0.0/17214.23.0.1 to 214.23.127.254214.23.127.25532,766
48214.23.128.0/17214.23.128.1 to 214.23.255.254214.23.255.25532,766
49214.24.0.0/17214.24.0.1 to 214.24.127.254214.24.127.25532,766
50214.24.128.0/17214.24.128.1 to 214.24.255.254214.24.255.25532,766
51214.25.0.0/17214.25.0.1 to 214.25.127.254214.25.127.25532,766
52214.25.128.0/17214.25.128.1 to 214.25.255.254214.25.255.25532,766
53214.26.0.0/17214.26.0.1 to 214.26.127.254214.26.127.25532,766
54214.26.128.0/17214.26.128.1 to 214.26.255.254214.26.255.25532,766
55214.27.0.0/17214.27.0.1 to 214.27.127.254214.27.127.25532,766
56214.27.128.0/17214.27.128.1 to 214.27.255.254214.27.255.25532,766
57214.28.0.0/17214.28.0.1 to 214.28.127.254214.28.127.25532,766
58214.28.128.0/17214.28.128.1 to 214.28.255.254214.28.255.25532,766
59214.29.0.0/17214.29.0.1 to 214.29.127.254214.29.127.25532,766
60214.29.128.0/17214.29.128.1 to 214.29.255.254214.29.255.25532,766
61214.30.0.0/17214.30.0.1 to 214.30.127.254214.30.127.25532,766
62214.30.128.0/17214.30.128.1 to 214.30.255.254214.30.255.25532,766
63214.31.0.0/17214.31.0.1 to 214.31.127.254214.31.127.25532,766
64214.31.128.0/17214.31.128.1 to 214.31.255.254214.31.255.25532,766
65214.32.0.0/17214.32.0.1 to 214.32.127.254214.32.127.25532,766
66214.32.128.0/17214.32.128.1 to 214.32.255.254214.32.255.25532,766
67214.33.0.0/17214.33.0.1 to 214.33.127.254214.33.127.25532,766
68214.33.128.0/17214.33.128.1 to 214.33.255.254214.33.255.25532,766
69214.34.0.0/17214.34.0.1 to 214.34.127.254214.34.127.25532,766
70214.34.128.0/17214.34.128.1 to 214.34.255.254214.34.255.25532,766
71214.35.0.0/17214.35.0.1 to 214.35.127.254214.35.127.25532,766
72214.35.128.0/17214.35.128.1 to 214.35.255.254214.35.255.25532,766
73214.36.0.0/17214.36.0.1 to 214.36.127.254214.36.127.25532,766
74214.36.128.0/17214.36.128.1 to 214.36.255.254214.36.255.25532,766
75214.37.0.0/17214.37.0.1 to 214.37.127.254214.37.127.25532,766
76214.37.128.0/17214.37.128.1 to 214.37.255.254214.37.255.25532,766
77214.38.0.0/17214.38.0.1 to 214.38.127.254214.38.127.25532,766
78214.38.128.0/17214.38.128.1 to 214.38.255.254214.38.255.25532,766
79214.39.0.0/17214.39.0.1 to 214.39.127.254214.39.127.25532,766
80214.39.128.0/17214.39.128.1 to 214.39.255.254214.39.255.25532,766
81214.40.0.0/17214.40.0.1 to 214.40.127.254214.40.127.25532,766
82214.40.128.0/17214.40.128.1 to 214.40.255.254214.40.255.25532,766
83214.41.0.0/17214.41.0.1 to 214.41.127.254214.41.127.25532,766
84214.41.128.0/17214.41.128.1 to 214.41.255.254214.41.255.25532,766
85214.42.0.0/17214.42.0.1 to 214.42.127.254214.42.127.25532,766
86214.42.128.0/17214.42.128.1 to 214.42.255.254214.42.255.25532,766
87214.43.0.0/17214.43.0.1 to 214.43.127.254214.43.127.25532,766
88214.43.128.0/17214.43.128.1 to 214.43.255.254214.43.255.25532,766
89214.44.0.0/17214.44.0.1 to 214.44.127.254214.44.127.25532,766
90214.44.128.0/17214.44.128.1 to 214.44.255.254214.44.255.25532,766
91214.45.0.0/17214.45.0.1 to 214.45.127.254214.45.127.25532,766
92214.45.128.0/17214.45.128.1 to 214.45.255.254214.45.255.25532,766
93214.46.0.0/17214.46.0.1 to 214.46.127.254214.46.127.25532,766
94214.46.128.0/17214.46.128.1 to 214.46.255.254214.46.255.25532,766
95214.47.0.0/17214.47.0.1 to 214.47.127.254214.47.127.25532,766
96214.47.128.0/17214.47.128.1 to 214.47.255.254214.47.255.25532,766
97214.48.0.0/17214.48.0.1 to 214.48.127.254214.48.127.25532,766
98214.48.128.0/17214.48.128.1 to 214.48.255.254214.48.255.25532,766
99214.49.0.0/17214.49.0.1 to 214.49.127.254214.49.127.25532,766
100214.49.128.0/17214.49.128.1 to 214.49.255.254214.49.255.25532,766
101214.50.0.0/17214.50.0.1 to 214.50.127.254214.50.127.25532,766
102214.50.128.0/17214.50.128.1 to 214.50.255.254214.50.255.25532,766
103214.51.0.0/17214.51.0.1 to 214.51.127.254214.51.127.25532,766
104214.51.128.0/17214.51.128.1 to 214.51.255.254214.51.255.25532,766
105214.52.0.0/17214.52.0.1 to 214.52.127.254214.52.127.25532,766
106214.52.128.0/17214.52.128.1 to 214.52.255.254214.52.255.25532,766
107214.53.0.0/17214.53.0.1 to 214.53.127.254214.53.127.25532,766
108214.53.128.0/17214.53.128.1 to 214.53.255.254214.53.255.25532,766
109214.54.0.0/17214.54.0.1 to 214.54.127.254214.54.127.25532,766
110214.54.128.0/17214.54.128.1 to 214.54.255.254214.54.255.25532,766
111214.55.0.0/17214.55.0.1 to 214.55.127.254214.55.127.25532,766
112214.55.128.0/17214.55.128.1 to 214.55.255.254214.55.255.25532,766
113214.56.0.0/17214.56.0.1 to 214.56.127.254214.56.127.25532,766
114214.56.128.0/17214.56.128.1 to 214.56.255.254214.56.255.25532,766
115214.57.0.0/17214.57.0.1 to 214.57.127.254214.57.127.25532,766
116214.57.128.0/17214.57.128.1 to 214.57.255.254214.57.255.25532,766
117214.58.0.0/17214.58.0.1 to 214.58.127.254214.58.127.25532,766
118214.58.128.0/17214.58.128.1 to 214.58.255.254214.58.255.25532,766
119214.59.0.0/17214.59.0.1 to 214.59.127.254214.59.127.25532,766
120214.59.128.0/17214.59.128.1 to 214.59.255.254214.59.255.25532,766
121214.60.0.0/17214.60.0.1 to 214.60.127.254214.60.127.25532,766
122214.60.128.0/17214.60.128.1 to 214.60.255.254214.60.255.25532,766
123214.61.0.0/17214.61.0.1 to 214.61.127.254214.61.127.25532,766
124214.61.128.0/17214.61.128.1 to 214.61.255.254214.61.255.25532,766
125214.62.0.0/17214.62.0.1 to 214.62.127.254214.62.127.25532,766
126214.62.128.0/17214.62.128.1 to 214.62.255.254214.62.255.25532,766
127214.63.0.0/17214.63.0.1 to 214.63.127.254214.63.127.25532,766
128214.63.128.0/17214.63.128.1 to 214.63.255.254214.63.255.25532,766
129214.64.0.0/17214.64.0.1 to 214.64.127.254214.64.127.25532,766
130214.64.128.0/17214.64.128.1 to 214.64.255.254214.64.255.25532,766
131214.65.0.0/17214.65.0.1 to 214.65.127.254214.65.127.25532,766
132214.65.128.0/17214.65.128.1 to 214.65.255.254214.65.255.25532,766
133214.66.0.0/17214.66.0.1 to 214.66.127.254214.66.127.25532,766
134214.66.128.0/17214.66.128.1 to 214.66.255.254214.66.255.25532,766
135214.67.0.0/17214.67.0.1 to 214.67.127.254214.67.127.25532,766
136214.67.128.0/17214.67.128.1 to 214.67.255.254214.67.255.25532,766
137214.68.0.0/17214.68.0.1 to 214.68.127.254214.68.127.25532,766
138214.68.128.0/17214.68.128.1 to 214.68.255.254214.68.255.25532,766
139214.69.0.0/17214.69.0.1 to 214.69.127.254214.69.127.25532,766
140214.69.128.0/17214.69.128.1 to 214.69.255.254214.69.255.25532,766
141214.70.0.0/17214.70.0.1 to 214.70.127.254214.70.127.25532,766
142214.70.128.0/17214.70.128.1 to 214.70.255.254214.70.255.25532,766
143214.71.0.0/17214.71.0.1 to 214.71.127.254214.71.127.25532,766
144214.71.128.0/17214.71.128.1 to 214.71.255.254214.71.255.25532,766
145214.72.0.0/17214.72.0.1 to 214.72.127.254214.72.127.25532,766
146214.72.128.0/17214.72.128.1 to 214.72.255.254214.72.255.25532,766
147214.73.0.0/17214.73.0.1 to 214.73.127.254214.73.127.25532,766
148214.73.128.0/17214.73.128.1 to 214.73.255.254214.73.255.25532,766
149214.74.0.0/17214.74.0.1 to 214.74.127.254214.74.127.25532,766
150214.74.128.0/17214.74.128.1 to 214.74.255.254214.74.255.25532,766
151214.75.0.0/17214.75.0.1 to 214.75.127.254214.75.127.25532,766
152214.75.128.0/17214.75.128.1 to 214.75.255.254214.75.255.25532,766
153214.76.0.0/17214.76.0.1 to 214.76.127.254214.76.127.25532,766
154214.76.128.0/17214.76.128.1 to 214.76.255.254214.76.255.25532,766
155214.77.0.0/17214.77.0.1 to 214.77.127.254214.77.127.25532,766
156214.77.128.0/17214.77.128.1 to 214.77.255.254214.77.255.25532,766
157214.78.0.0/17214.78.0.1 to 214.78.127.254214.78.127.25532,766
158214.78.128.0/17214.78.128.1 to 214.78.255.254214.78.255.25532,766
159214.79.0.0/17214.79.0.1 to 214.79.127.254214.79.127.25532,766
160214.79.128.0/17214.79.128.1 to 214.79.255.254214.79.255.25532,766
161214.80.0.0/17214.80.0.1 to 214.80.127.254214.80.127.25532,766
162214.80.128.0/17214.80.128.1 to 214.80.255.254214.80.255.25532,766
163214.81.0.0/17214.81.0.1 to 214.81.127.254214.81.127.25532,766
164214.81.128.0/17214.81.128.1 to 214.81.255.254214.81.255.25532,766
165214.82.0.0/17214.82.0.1 to 214.82.127.254214.82.127.25532,766
166214.82.128.0/17214.82.128.1 to 214.82.255.254214.82.255.25532,766
167214.83.0.0/17214.83.0.1 to 214.83.127.254214.83.127.25532,766
168214.83.128.0/17214.83.128.1 to 214.83.255.254214.83.255.25532,766
169214.84.0.0/17214.84.0.1 to 214.84.127.254214.84.127.25532,766
170214.84.128.0/17214.84.128.1 to 214.84.255.254214.84.255.25532,766
171214.85.0.0/17214.85.0.1 to 214.85.127.254214.85.127.25532,766
172214.85.128.0/17214.85.128.1 to 214.85.255.254214.85.255.25532,766
173214.86.0.0/17214.86.0.1 to 214.86.127.254214.86.127.25532,766
174214.86.128.0/17214.86.128.1 to 214.86.255.254214.86.255.25532,766
175214.87.0.0/17214.87.0.1 to 214.87.127.254214.87.127.25532,766
176214.87.128.0/17214.87.128.1 to 214.87.255.254214.87.255.25532,766
177214.88.0.0/17214.88.0.1 to 214.88.127.254214.88.127.25532,766
178214.88.128.0/17214.88.128.1 to 214.88.255.254214.88.255.25532,766
179214.89.0.0/17214.89.0.1 to 214.89.127.254214.89.127.25532,766
180214.89.128.0/17214.89.128.1 to 214.89.255.254214.89.255.25532,766
181214.90.0.0/17214.90.0.1 to 214.90.127.254214.90.127.25532,766
182214.90.128.0/17214.90.128.1 to 214.90.255.254214.90.255.25532,766
183214.91.0.0/17214.91.0.1 to 214.91.127.254214.91.127.25532,766
184214.91.128.0/17214.91.128.1 to 214.91.255.254214.91.255.25532,766
185214.92.0.0/17214.92.0.1 to 214.92.127.254214.92.127.25532,766
186214.92.128.0/17214.92.128.1 to 214.92.255.254214.92.255.25532,766
187214.93.0.0/17214.93.0.1 to 214.93.127.254214.93.127.25532,766
188214.93.128.0/17214.93.128.1 to 214.93.255.254214.93.255.25532,766
189214.94.0.0/17214.94.0.1 to 214.94.127.254214.94.127.25532,766
190214.94.128.0/17214.94.128.1 to 214.94.255.254214.94.255.25532,766
191214.95.0.0/17214.95.0.1 to 214.95.127.254214.95.127.25532,766
192214.95.128.0/17214.95.128.1 to 214.95.255.254214.95.255.25532,766
193214.96.0.0/17214.96.0.1 to 214.96.127.254214.96.127.25532,766
194214.96.128.0/17214.96.128.1 to 214.96.255.254214.96.255.25532,766
195214.97.0.0/17214.97.0.1 to 214.97.127.254214.97.127.25532,766
196214.97.128.0/17214.97.128.1 to 214.97.255.254214.97.255.25532,766
197214.98.0.0/17214.98.0.1 to 214.98.127.254214.98.127.25532,766
198214.98.128.0/17214.98.128.1 to 214.98.255.254214.98.255.25532,766
199214.99.0.0/17214.99.0.1 to 214.99.127.254214.99.127.25532,766
200214.99.128.0/17214.99.128.1 to 214.99.255.254214.99.255.25532,766
201214.100.0.0/17214.100.0.1 to 214.100.127.254214.100.127.25532,766
202214.100.128.0/17214.100.128.1 to 214.100.255.254214.100.255.25532,766
203214.101.0.0/17214.101.0.1 to 214.101.127.254214.101.127.25532,766
204214.101.128.0/17214.101.128.1 to 214.101.255.254214.101.255.25532,766
205214.102.0.0/17214.102.0.1 to 214.102.127.254214.102.127.25532,766
206214.102.128.0/17214.102.128.1 to 214.102.255.254214.102.255.25532,766
207214.103.0.0/17214.103.0.1 to 214.103.127.254214.103.127.25532,766
208214.103.128.0/17214.103.128.1 to 214.103.255.254214.103.255.25532,766
209214.104.0.0/17214.104.0.1 to 214.104.127.254214.104.127.25532,766
210214.104.128.0/17214.104.128.1 to 214.104.255.254214.104.255.25532,766
211214.105.0.0/17214.105.0.1 to 214.105.127.254214.105.127.25532,766
212214.105.128.0/17214.105.128.1 to 214.105.255.254214.105.255.25532,766
213214.106.0.0/17214.106.0.1 to 214.106.127.254214.106.127.25532,766
214214.106.128.0/17214.106.128.1 to 214.106.255.254214.106.255.25532,766
215214.107.0.0/17214.107.0.1 to 214.107.127.254214.107.127.25532,766
216214.107.128.0/17214.107.128.1 to 214.107.255.254214.107.255.25532,766
217214.108.0.0/17214.108.0.1 to 214.108.127.254214.108.127.25532,766
218214.108.128.0/17214.108.128.1 to 214.108.255.254214.108.255.25532,766
219214.109.0.0/17214.109.0.1 to 214.109.127.254214.109.127.25532,766
220214.109.128.0/17214.109.128.1 to 214.109.255.254214.109.255.25532,766
221214.110.0.0/17214.110.0.1 to 214.110.127.254214.110.127.25532,766
222214.110.128.0/17214.110.128.1 to 214.110.255.254214.110.255.25532,766
223214.111.0.0/17214.111.0.1 to 214.111.127.254214.111.127.25532,766
224214.111.128.0/17214.111.128.1 to 214.111.255.254214.111.255.25532,766
225214.112.0.0/17214.112.0.1 to 214.112.127.254214.112.127.25532,766
226214.112.128.0/17214.112.128.1 to 214.112.255.254214.112.255.25532,766
227214.113.0.0/17214.113.0.1 to 214.113.127.254214.113.127.25532,766
228214.113.128.0/17214.113.128.1 to 214.113.255.254214.113.255.25532,766
229214.114.0.0/17214.114.0.1 to 214.114.127.254214.114.127.25532,766
230214.114.128.0/17214.114.128.1 to 214.114.255.254214.114.255.25532,766
231214.115.0.0/17214.115.0.1 to 214.115.127.254214.115.127.25532,766
232214.115.128.0/17214.115.128.1 to 214.115.255.254214.115.255.25532,766
233214.116.0.0/17214.116.0.1 to 214.116.127.254214.116.127.25532,766
234214.116.128.0/17214.116.128.1 to 214.116.255.254214.116.255.25532,766
235214.117.0.0/17214.117.0.1 to 214.117.127.254214.117.127.25532,766
236214.117.128.0/17214.117.128.1 to 214.117.255.254214.117.255.25532,766
237214.118.0.0/17214.118.0.1 to 214.118.127.254214.118.127.25532,766
238214.118.128.0/17214.118.128.1 to 214.118.255.254214.118.255.25532,766
239214.119.0.0/17214.119.0.1 to 214.119.127.254214.119.127.25532,766
240214.119.128.0/17214.119.128.1 to 214.119.255.254214.119.255.25532,766
241214.120.0.0/17214.120.0.1 to 214.120.127.254214.120.127.25532,766
242214.120.128.0/17214.120.128.1 to 214.120.255.254214.120.255.25532,766
243214.121.0.0/17214.121.0.1 to 214.121.127.254214.121.127.25532,766
244214.121.128.0/17214.121.128.1 to 214.121.255.254214.121.255.25532,766
245214.122.0.0/17214.122.0.1 to 214.122.127.254214.122.127.25532,766
246214.122.128.0/17214.122.128.1 to 214.122.255.254214.122.255.25532,766
247214.123.0.0/17214.123.0.1 to 214.123.127.254214.123.127.25532,766
248214.123.128.0/17214.123.128.1 to 214.123.255.254214.123.255.25532,766
249214.124.0.0/17214.124.0.1 to 214.124.127.254214.124.127.25532,766
250214.124.128.0/17214.124.128.1 to 214.124.255.254214.124.255.25532,766
251214.125.0.0/17214.125.0.1 to 214.125.127.254214.125.127.25532,766
252214.125.128.0/17214.125.128.1 to 214.125.255.254214.125.255.25532,766
253214.126.0.0/17214.126.0.1 to 214.126.127.254214.126.127.25532,766
254214.126.128.0/17214.126.128.1 to 214.126.255.254214.126.255.25532,766
255214.127.0.0/17214.127.0.1 to 214.127.127.254214.127.127.25532,766
256214.127.128.0/17214.127.128.1 to 214.127.255.254214.127.255.25532,766

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

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.