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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.

Network182.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
182.0.0.0
Broadcast address
182.255.255.255
First usable
182.0.0.1
Last usable
182.255.255.254
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
B (default /16)
As numbers
Hex B6000000 · Integer 3053453312 to 3070230527
Reverse DNS zone
182.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10110110..00000000.00000000.00000000182.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10110110..00000000.00000000.00000000182.0.0.0
Broadcast10110110..11111111.11111111.11111111182.255.255.255
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)

182.0.0.0/8 makes 512 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1182.0.0.0/17182.0.0.1 to 182.0.127.254182.0.127.25532,766
2182.0.128.0/17182.0.128.1 to 182.0.255.254182.0.255.25532,766
3182.1.0.0/17182.1.0.1 to 182.1.127.254182.1.127.25532,766
4182.1.128.0/17182.1.128.1 to 182.1.255.254182.1.255.25532,766
5182.2.0.0/17182.2.0.1 to 182.2.127.254182.2.127.25532,766
6182.2.128.0/17182.2.128.1 to 182.2.255.254182.2.255.25532,766
7182.3.0.0/17182.3.0.1 to 182.3.127.254182.3.127.25532,766
8182.3.128.0/17182.3.128.1 to 182.3.255.254182.3.255.25532,766
9182.4.0.0/17182.4.0.1 to 182.4.127.254182.4.127.25532,766
10182.4.128.0/17182.4.128.1 to 182.4.255.254182.4.255.25532,766
11182.5.0.0/17182.5.0.1 to 182.5.127.254182.5.127.25532,766
12182.5.128.0/17182.5.128.1 to 182.5.255.254182.5.255.25532,766
13182.6.0.0/17182.6.0.1 to 182.6.127.254182.6.127.25532,766
14182.6.128.0/17182.6.128.1 to 182.6.255.254182.6.255.25532,766
15182.7.0.0/17182.7.0.1 to 182.7.127.254182.7.127.25532,766
16182.7.128.0/17182.7.128.1 to 182.7.255.254182.7.255.25532,766
17182.8.0.0/17182.8.0.1 to 182.8.127.254182.8.127.25532,766
18182.8.128.0/17182.8.128.1 to 182.8.255.254182.8.255.25532,766
19182.9.0.0/17182.9.0.1 to 182.9.127.254182.9.127.25532,766
20182.9.128.0/17182.9.128.1 to 182.9.255.254182.9.255.25532,766
21182.10.0.0/17182.10.0.1 to 182.10.127.254182.10.127.25532,766
22182.10.128.0/17182.10.128.1 to 182.10.255.254182.10.255.25532,766
23182.11.0.0/17182.11.0.1 to 182.11.127.254182.11.127.25532,766
24182.11.128.0/17182.11.128.1 to 182.11.255.254182.11.255.25532,766
25182.12.0.0/17182.12.0.1 to 182.12.127.254182.12.127.25532,766
26182.12.128.0/17182.12.128.1 to 182.12.255.254182.12.255.25532,766
27182.13.0.0/17182.13.0.1 to 182.13.127.254182.13.127.25532,766
28182.13.128.0/17182.13.128.1 to 182.13.255.254182.13.255.25532,766
29182.14.0.0/17182.14.0.1 to 182.14.127.254182.14.127.25532,766
30182.14.128.0/17182.14.128.1 to 182.14.255.254182.14.255.25532,766
31182.15.0.0/17182.15.0.1 to 182.15.127.254182.15.127.25532,766
32182.15.128.0/17182.15.128.1 to 182.15.255.254182.15.255.25532,766
33182.16.0.0/17182.16.0.1 to 182.16.127.254182.16.127.25532,766
34182.16.128.0/17182.16.128.1 to 182.16.255.254182.16.255.25532,766
35182.17.0.0/17182.17.0.1 to 182.17.127.254182.17.127.25532,766
36182.17.128.0/17182.17.128.1 to 182.17.255.254182.17.255.25532,766
37182.18.0.0/17182.18.0.1 to 182.18.127.254182.18.127.25532,766
38182.18.128.0/17182.18.128.1 to 182.18.255.254182.18.255.25532,766
39182.19.0.0/17182.19.0.1 to 182.19.127.254182.19.127.25532,766
40182.19.128.0/17182.19.128.1 to 182.19.255.254182.19.255.25532,766
41182.20.0.0/17182.20.0.1 to 182.20.127.254182.20.127.25532,766
42182.20.128.0/17182.20.128.1 to 182.20.255.254182.20.255.25532,766
43182.21.0.0/17182.21.0.1 to 182.21.127.254182.21.127.25532,766
44182.21.128.0/17182.21.128.1 to 182.21.255.254182.21.255.25532,766
45182.22.0.0/17182.22.0.1 to 182.22.127.254182.22.127.25532,766
46182.22.128.0/17182.22.128.1 to 182.22.255.254182.22.255.25532,766
47182.23.0.0/17182.23.0.1 to 182.23.127.254182.23.127.25532,766
48182.23.128.0/17182.23.128.1 to 182.23.255.254182.23.255.25532,766
49182.24.0.0/17182.24.0.1 to 182.24.127.254182.24.127.25532,766
50182.24.128.0/17182.24.128.1 to 182.24.255.254182.24.255.25532,766
51182.25.0.0/17182.25.0.1 to 182.25.127.254182.25.127.25532,766
52182.25.128.0/17182.25.128.1 to 182.25.255.254182.25.255.25532,766
53182.26.0.0/17182.26.0.1 to 182.26.127.254182.26.127.25532,766
54182.26.128.0/17182.26.128.1 to 182.26.255.254182.26.255.25532,766
55182.27.0.0/17182.27.0.1 to 182.27.127.254182.27.127.25532,766
56182.27.128.0/17182.27.128.1 to 182.27.255.254182.27.255.25532,766
57182.28.0.0/17182.28.0.1 to 182.28.127.254182.28.127.25532,766
58182.28.128.0/17182.28.128.1 to 182.28.255.254182.28.255.25532,766
59182.29.0.0/17182.29.0.1 to 182.29.127.254182.29.127.25532,766
60182.29.128.0/17182.29.128.1 to 182.29.255.254182.29.255.25532,766
61182.30.0.0/17182.30.0.1 to 182.30.127.254182.30.127.25532,766
62182.30.128.0/17182.30.128.1 to 182.30.255.254182.30.255.25532,766
63182.31.0.0/17182.31.0.1 to 182.31.127.254182.31.127.25532,766
64182.31.128.0/17182.31.128.1 to 182.31.255.254182.31.255.25532,766
65182.32.0.0/17182.32.0.1 to 182.32.127.254182.32.127.25532,766
66182.32.128.0/17182.32.128.1 to 182.32.255.254182.32.255.25532,766
67182.33.0.0/17182.33.0.1 to 182.33.127.254182.33.127.25532,766
68182.33.128.0/17182.33.128.1 to 182.33.255.254182.33.255.25532,766
69182.34.0.0/17182.34.0.1 to 182.34.127.254182.34.127.25532,766
70182.34.128.0/17182.34.128.1 to 182.34.255.254182.34.255.25532,766
71182.35.0.0/17182.35.0.1 to 182.35.127.254182.35.127.25532,766
72182.35.128.0/17182.35.128.1 to 182.35.255.254182.35.255.25532,766
73182.36.0.0/17182.36.0.1 to 182.36.127.254182.36.127.25532,766
74182.36.128.0/17182.36.128.1 to 182.36.255.254182.36.255.25532,766
75182.37.0.0/17182.37.0.1 to 182.37.127.254182.37.127.25532,766
76182.37.128.0/17182.37.128.1 to 182.37.255.254182.37.255.25532,766
77182.38.0.0/17182.38.0.1 to 182.38.127.254182.38.127.25532,766
78182.38.128.0/17182.38.128.1 to 182.38.255.254182.38.255.25532,766
79182.39.0.0/17182.39.0.1 to 182.39.127.254182.39.127.25532,766
80182.39.128.0/17182.39.128.1 to 182.39.255.254182.39.255.25532,766
81182.40.0.0/17182.40.0.1 to 182.40.127.254182.40.127.25532,766
82182.40.128.0/17182.40.128.1 to 182.40.255.254182.40.255.25532,766
83182.41.0.0/17182.41.0.1 to 182.41.127.254182.41.127.25532,766
84182.41.128.0/17182.41.128.1 to 182.41.255.254182.41.255.25532,766
85182.42.0.0/17182.42.0.1 to 182.42.127.254182.42.127.25532,766
86182.42.128.0/17182.42.128.1 to 182.42.255.254182.42.255.25532,766
87182.43.0.0/17182.43.0.1 to 182.43.127.254182.43.127.25532,766
88182.43.128.0/17182.43.128.1 to 182.43.255.254182.43.255.25532,766
89182.44.0.0/17182.44.0.1 to 182.44.127.254182.44.127.25532,766
90182.44.128.0/17182.44.128.1 to 182.44.255.254182.44.255.25532,766
91182.45.0.0/17182.45.0.1 to 182.45.127.254182.45.127.25532,766
92182.45.128.0/17182.45.128.1 to 182.45.255.254182.45.255.25532,766
93182.46.0.0/17182.46.0.1 to 182.46.127.254182.46.127.25532,766
94182.46.128.0/17182.46.128.1 to 182.46.255.254182.46.255.25532,766
95182.47.0.0/17182.47.0.1 to 182.47.127.254182.47.127.25532,766
96182.47.128.0/17182.47.128.1 to 182.47.255.254182.47.255.25532,766
97182.48.0.0/17182.48.0.1 to 182.48.127.254182.48.127.25532,766
98182.48.128.0/17182.48.128.1 to 182.48.255.254182.48.255.25532,766
99182.49.0.0/17182.49.0.1 to 182.49.127.254182.49.127.25532,766
100182.49.128.0/17182.49.128.1 to 182.49.255.254182.49.255.25532,766
101182.50.0.0/17182.50.0.1 to 182.50.127.254182.50.127.25532,766
102182.50.128.0/17182.50.128.1 to 182.50.255.254182.50.255.25532,766
103182.51.0.0/17182.51.0.1 to 182.51.127.254182.51.127.25532,766
104182.51.128.0/17182.51.128.1 to 182.51.255.254182.51.255.25532,766
105182.52.0.0/17182.52.0.1 to 182.52.127.254182.52.127.25532,766
106182.52.128.0/17182.52.128.1 to 182.52.255.254182.52.255.25532,766
107182.53.0.0/17182.53.0.1 to 182.53.127.254182.53.127.25532,766
108182.53.128.0/17182.53.128.1 to 182.53.255.254182.53.255.25532,766
109182.54.0.0/17182.54.0.1 to 182.54.127.254182.54.127.25532,766
110182.54.128.0/17182.54.128.1 to 182.54.255.254182.54.255.25532,766
111182.55.0.0/17182.55.0.1 to 182.55.127.254182.55.127.25532,766
112182.55.128.0/17182.55.128.1 to 182.55.255.254182.55.255.25532,766
113182.56.0.0/17182.56.0.1 to 182.56.127.254182.56.127.25532,766
114182.56.128.0/17182.56.128.1 to 182.56.255.254182.56.255.25532,766
115182.57.0.0/17182.57.0.1 to 182.57.127.254182.57.127.25532,766
116182.57.128.0/17182.57.128.1 to 182.57.255.254182.57.255.25532,766
117182.58.0.0/17182.58.0.1 to 182.58.127.254182.58.127.25532,766
118182.58.128.0/17182.58.128.1 to 182.58.255.254182.58.255.25532,766
119182.59.0.0/17182.59.0.1 to 182.59.127.254182.59.127.25532,766
120182.59.128.0/17182.59.128.1 to 182.59.255.254182.59.255.25532,766
121182.60.0.0/17182.60.0.1 to 182.60.127.254182.60.127.25532,766
122182.60.128.0/17182.60.128.1 to 182.60.255.254182.60.255.25532,766
123182.61.0.0/17182.61.0.1 to 182.61.127.254182.61.127.25532,766
124182.61.128.0/17182.61.128.1 to 182.61.255.254182.61.255.25532,766
125182.62.0.0/17182.62.0.1 to 182.62.127.254182.62.127.25532,766
126182.62.128.0/17182.62.128.1 to 182.62.255.254182.62.255.25532,766
127182.63.0.0/17182.63.0.1 to 182.63.127.254182.63.127.25532,766
128182.63.128.0/17182.63.128.1 to 182.63.255.254182.63.255.25532,766
129182.64.0.0/17182.64.0.1 to 182.64.127.254182.64.127.25532,766
130182.64.128.0/17182.64.128.1 to 182.64.255.254182.64.255.25532,766
131182.65.0.0/17182.65.0.1 to 182.65.127.254182.65.127.25532,766
132182.65.128.0/17182.65.128.1 to 182.65.255.254182.65.255.25532,766
133182.66.0.0/17182.66.0.1 to 182.66.127.254182.66.127.25532,766
134182.66.128.0/17182.66.128.1 to 182.66.255.254182.66.255.25532,766
135182.67.0.0/17182.67.0.1 to 182.67.127.254182.67.127.25532,766
136182.67.128.0/17182.67.128.1 to 182.67.255.254182.67.255.25532,766
137182.68.0.0/17182.68.0.1 to 182.68.127.254182.68.127.25532,766
138182.68.128.0/17182.68.128.1 to 182.68.255.254182.68.255.25532,766
139182.69.0.0/17182.69.0.1 to 182.69.127.254182.69.127.25532,766
140182.69.128.0/17182.69.128.1 to 182.69.255.254182.69.255.25532,766
141182.70.0.0/17182.70.0.1 to 182.70.127.254182.70.127.25532,766
142182.70.128.0/17182.70.128.1 to 182.70.255.254182.70.255.25532,766
143182.71.0.0/17182.71.0.1 to 182.71.127.254182.71.127.25532,766
144182.71.128.0/17182.71.128.1 to 182.71.255.254182.71.255.25532,766
145182.72.0.0/17182.72.0.1 to 182.72.127.254182.72.127.25532,766
146182.72.128.0/17182.72.128.1 to 182.72.255.254182.72.255.25532,766
147182.73.0.0/17182.73.0.1 to 182.73.127.254182.73.127.25532,766
148182.73.128.0/17182.73.128.1 to 182.73.255.254182.73.255.25532,766
149182.74.0.0/17182.74.0.1 to 182.74.127.254182.74.127.25532,766
150182.74.128.0/17182.74.128.1 to 182.74.255.254182.74.255.25532,766
151182.75.0.0/17182.75.0.1 to 182.75.127.254182.75.127.25532,766
152182.75.128.0/17182.75.128.1 to 182.75.255.254182.75.255.25532,766
153182.76.0.0/17182.76.0.1 to 182.76.127.254182.76.127.25532,766
154182.76.128.0/17182.76.128.1 to 182.76.255.254182.76.255.25532,766
155182.77.0.0/17182.77.0.1 to 182.77.127.254182.77.127.25532,766
156182.77.128.0/17182.77.128.1 to 182.77.255.254182.77.255.25532,766
157182.78.0.0/17182.78.0.1 to 182.78.127.254182.78.127.25532,766
158182.78.128.0/17182.78.128.1 to 182.78.255.254182.78.255.25532,766
159182.79.0.0/17182.79.0.1 to 182.79.127.254182.79.127.25532,766
160182.79.128.0/17182.79.128.1 to 182.79.255.254182.79.255.25532,766
161182.80.0.0/17182.80.0.1 to 182.80.127.254182.80.127.25532,766
162182.80.128.0/17182.80.128.1 to 182.80.255.254182.80.255.25532,766
163182.81.0.0/17182.81.0.1 to 182.81.127.254182.81.127.25532,766
164182.81.128.0/17182.81.128.1 to 182.81.255.254182.81.255.25532,766
165182.82.0.0/17182.82.0.1 to 182.82.127.254182.82.127.25532,766
166182.82.128.0/17182.82.128.1 to 182.82.255.254182.82.255.25532,766
167182.83.0.0/17182.83.0.1 to 182.83.127.254182.83.127.25532,766
168182.83.128.0/17182.83.128.1 to 182.83.255.254182.83.255.25532,766
169182.84.0.0/17182.84.0.1 to 182.84.127.254182.84.127.25532,766
170182.84.128.0/17182.84.128.1 to 182.84.255.254182.84.255.25532,766
171182.85.0.0/17182.85.0.1 to 182.85.127.254182.85.127.25532,766
172182.85.128.0/17182.85.128.1 to 182.85.255.254182.85.255.25532,766
173182.86.0.0/17182.86.0.1 to 182.86.127.254182.86.127.25532,766
174182.86.128.0/17182.86.128.1 to 182.86.255.254182.86.255.25532,766
175182.87.0.0/17182.87.0.1 to 182.87.127.254182.87.127.25532,766
176182.87.128.0/17182.87.128.1 to 182.87.255.254182.87.255.25532,766
177182.88.0.0/17182.88.0.1 to 182.88.127.254182.88.127.25532,766
178182.88.128.0/17182.88.128.1 to 182.88.255.254182.88.255.25532,766
179182.89.0.0/17182.89.0.1 to 182.89.127.254182.89.127.25532,766
180182.89.128.0/17182.89.128.1 to 182.89.255.254182.89.255.25532,766
181182.90.0.0/17182.90.0.1 to 182.90.127.254182.90.127.25532,766
182182.90.128.0/17182.90.128.1 to 182.90.255.254182.90.255.25532,766
183182.91.0.0/17182.91.0.1 to 182.91.127.254182.91.127.25532,766
184182.91.128.0/17182.91.128.1 to 182.91.255.254182.91.255.25532,766
185182.92.0.0/17182.92.0.1 to 182.92.127.254182.92.127.25532,766
186182.92.128.0/17182.92.128.1 to 182.92.255.254182.92.255.25532,766
187182.93.0.0/17182.93.0.1 to 182.93.127.254182.93.127.25532,766
188182.93.128.0/17182.93.128.1 to 182.93.255.254182.93.255.25532,766
189182.94.0.0/17182.94.0.1 to 182.94.127.254182.94.127.25532,766
190182.94.128.0/17182.94.128.1 to 182.94.255.254182.94.255.25532,766
191182.95.0.0/17182.95.0.1 to 182.95.127.254182.95.127.25532,766
192182.95.128.0/17182.95.128.1 to 182.95.255.254182.95.255.25532,766
193182.96.0.0/17182.96.0.1 to 182.96.127.254182.96.127.25532,766
194182.96.128.0/17182.96.128.1 to 182.96.255.254182.96.255.25532,766
195182.97.0.0/17182.97.0.1 to 182.97.127.254182.97.127.25532,766
196182.97.128.0/17182.97.128.1 to 182.97.255.254182.97.255.25532,766
197182.98.0.0/17182.98.0.1 to 182.98.127.254182.98.127.25532,766
198182.98.128.0/17182.98.128.1 to 182.98.255.254182.98.255.25532,766
199182.99.0.0/17182.99.0.1 to 182.99.127.254182.99.127.25532,766
200182.99.128.0/17182.99.128.1 to 182.99.255.254182.99.255.25532,766
201182.100.0.0/17182.100.0.1 to 182.100.127.254182.100.127.25532,766
202182.100.128.0/17182.100.128.1 to 182.100.255.254182.100.255.25532,766
203182.101.0.0/17182.101.0.1 to 182.101.127.254182.101.127.25532,766
204182.101.128.0/17182.101.128.1 to 182.101.255.254182.101.255.25532,766
205182.102.0.0/17182.102.0.1 to 182.102.127.254182.102.127.25532,766
206182.102.128.0/17182.102.128.1 to 182.102.255.254182.102.255.25532,766
207182.103.0.0/17182.103.0.1 to 182.103.127.254182.103.127.25532,766
208182.103.128.0/17182.103.128.1 to 182.103.255.254182.103.255.25532,766
209182.104.0.0/17182.104.0.1 to 182.104.127.254182.104.127.25532,766
210182.104.128.0/17182.104.128.1 to 182.104.255.254182.104.255.25532,766
211182.105.0.0/17182.105.0.1 to 182.105.127.254182.105.127.25532,766
212182.105.128.0/17182.105.128.1 to 182.105.255.254182.105.255.25532,766
213182.106.0.0/17182.106.0.1 to 182.106.127.254182.106.127.25532,766
214182.106.128.0/17182.106.128.1 to 182.106.255.254182.106.255.25532,766
215182.107.0.0/17182.107.0.1 to 182.107.127.254182.107.127.25532,766
216182.107.128.0/17182.107.128.1 to 182.107.255.254182.107.255.25532,766
217182.108.0.0/17182.108.0.1 to 182.108.127.254182.108.127.25532,766
218182.108.128.0/17182.108.128.1 to 182.108.255.254182.108.255.25532,766
219182.109.0.0/17182.109.0.1 to 182.109.127.254182.109.127.25532,766
220182.109.128.0/17182.109.128.1 to 182.109.255.254182.109.255.25532,766
221182.110.0.0/17182.110.0.1 to 182.110.127.254182.110.127.25532,766
222182.110.128.0/17182.110.128.1 to 182.110.255.254182.110.255.25532,766
223182.111.0.0/17182.111.0.1 to 182.111.127.254182.111.127.25532,766
224182.111.128.0/17182.111.128.1 to 182.111.255.254182.111.255.25532,766
225182.112.0.0/17182.112.0.1 to 182.112.127.254182.112.127.25532,766
226182.112.128.0/17182.112.128.1 to 182.112.255.254182.112.255.25532,766
227182.113.0.0/17182.113.0.1 to 182.113.127.254182.113.127.25532,766
228182.113.128.0/17182.113.128.1 to 182.113.255.254182.113.255.25532,766
229182.114.0.0/17182.114.0.1 to 182.114.127.254182.114.127.25532,766
230182.114.128.0/17182.114.128.1 to 182.114.255.254182.114.255.25532,766
231182.115.0.0/17182.115.0.1 to 182.115.127.254182.115.127.25532,766
232182.115.128.0/17182.115.128.1 to 182.115.255.254182.115.255.25532,766
233182.116.0.0/17182.116.0.1 to 182.116.127.254182.116.127.25532,766
234182.116.128.0/17182.116.128.1 to 182.116.255.254182.116.255.25532,766
235182.117.0.0/17182.117.0.1 to 182.117.127.254182.117.127.25532,766
236182.117.128.0/17182.117.128.1 to 182.117.255.254182.117.255.25532,766
237182.118.0.0/17182.118.0.1 to 182.118.127.254182.118.127.25532,766
238182.118.128.0/17182.118.128.1 to 182.118.255.254182.118.255.25532,766
239182.119.0.0/17182.119.0.1 to 182.119.127.254182.119.127.25532,766
240182.119.128.0/17182.119.128.1 to 182.119.255.254182.119.255.25532,766
241182.120.0.0/17182.120.0.1 to 182.120.127.254182.120.127.25532,766
242182.120.128.0/17182.120.128.1 to 182.120.255.254182.120.255.25532,766
243182.121.0.0/17182.121.0.1 to 182.121.127.254182.121.127.25532,766
244182.121.128.0/17182.121.128.1 to 182.121.255.254182.121.255.25532,766
245182.122.0.0/17182.122.0.1 to 182.122.127.254182.122.127.25532,766
246182.122.128.0/17182.122.128.1 to 182.122.255.254182.122.255.25532,766
247182.123.0.0/17182.123.0.1 to 182.123.127.254182.123.127.25532,766
248182.123.128.0/17182.123.128.1 to 182.123.255.254182.123.255.25532,766
249182.124.0.0/17182.124.0.1 to 182.124.127.254182.124.127.25532,766
250182.124.128.0/17182.124.128.1 to 182.124.255.254182.124.255.25532,766
251182.125.0.0/17182.125.0.1 to 182.125.127.254182.125.127.25532,766
252182.125.128.0/17182.125.128.1 to 182.125.255.254182.125.255.25532,766
253182.126.0.0/17182.126.0.1 to 182.126.127.254182.126.127.25532,766
254182.126.128.0/17182.126.128.1 to 182.126.255.254182.126.255.25532,766
255182.127.0.0/17182.127.0.1 to 182.127.127.254182.127.127.25532,766
256182.127.128.0/17182.127.128.1 to 182.127.255.254182.127.255.25532,766

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.