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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.

Network176.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
176.0.0.0
Broadcast address
176.255.255.255
First usable
176.0.0.1
Last usable
176.255.255.254
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 B0000000 · Integer 2952790016 to 2969567231
Reverse DNS zone
176.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10110000..00000000.00000000.00000000176.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10110000..00000000.00000000.00000000176.0.0.0
Broadcast10110000..11111111.11111111.11111111176.255.255.255
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)

176.0.0.0/8 makes 512 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1176.0.0.0/17176.0.0.1 to 176.0.127.254176.0.127.25532,766
2176.0.128.0/17176.0.128.1 to 176.0.255.254176.0.255.25532,766
3176.1.0.0/17176.1.0.1 to 176.1.127.254176.1.127.25532,766
4176.1.128.0/17176.1.128.1 to 176.1.255.254176.1.255.25532,766
5176.2.0.0/17176.2.0.1 to 176.2.127.254176.2.127.25532,766
6176.2.128.0/17176.2.128.1 to 176.2.255.254176.2.255.25532,766
7176.3.0.0/17176.3.0.1 to 176.3.127.254176.3.127.25532,766
8176.3.128.0/17176.3.128.1 to 176.3.255.254176.3.255.25532,766
9176.4.0.0/17176.4.0.1 to 176.4.127.254176.4.127.25532,766
10176.4.128.0/17176.4.128.1 to 176.4.255.254176.4.255.25532,766
11176.5.0.0/17176.5.0.1 to 176.5.127.254176.5.127.25532,766
12176.5.128.0/17176.5.128.1 to 176.5.255.254176.5.255.25532,766
13176.6.0.0/17176.6.0.1 to 176.6.127.254176.6.127.25532,766
14176.6.128.0/17176.6.128.1 to 176.6.255.254176.6.255.25532,766
15176.7.0.0/17176.7.0.1 to 176.7.127.254176.7.127.25532,766
16176.7.128.0/17176.7.128.1 to 176.7.255.254176.7.255.25532,766
17176.8.0.0/17176.8.0.1 to 176.8.127.254176.8.127.25532,766
18176.8.128.0/17176.8.128.1 to 176.8.255.254176.8.255.25532,766
19176.9.0.0/17176.9.0.1 to 176.9.127.254176.9.127.25532,766
20176.9.128.0/17176.9.128.1 to 176.9.255.254176.9.255.25532,766
21176.10.0.0/17176.10.0.1 to 176.10.127.254176.10.127.25532,766
22176.10.128.0/17176.10.128.1 to 176.10.255.254176.10.255.25532,766
23176.11.0.0/17176.11.0.1 to 176.11.127.254176.11.127.25532,766
24176.11.128.0/17176.11.128.1 to 176.11.255.254176.11.255.25532,766
25176.12.0.0/17176.12.0.1 to 176.12.127.254176.12.127.25532,766
26176.12.128.0/17176.12.128.1 to 176.12.255.254176.12.255.25532,766
27176.13.0.0/17176.13.0.1 to 176.13.127.254176.13.127.25532,766
28176.13.128.0/17176.13.128.1 to 176.13.255.254176.13.255.25532,766
29176.14.0.0/17176.14.0.1 to 176.14.127.254176.14.127.25532,766
30176.14.128.0/17176.14.128.1 to 176.14.255.254176.14.255.25532,766
31176.15.0.0/17176.15.0.1 to 176.15.127.254176.15.127.25532,766
32176.15.128.0/17176.15.128.1 to 176.15.255.254176.15.255.25532,766
33176.16.0.0/17176.16.0.1 to 176.16.127.254176.16.127.25532,766
34176.16.128.0/17176.16.128.1 to 176.16.255.254176.16.255.25532,766
35176.17.0.0/17176.17.0.1 to 176.17.127.254176.17.127.25532,766
36176.17.128.0/17176.17.128.1 to 176.17.255.254176.17.255.25532,766
37176.18.0.0/17176.18.0.1 to 176.18.127.254176.18.127.25532,766
38176.18.128.0/17176.18.128.1 to 176.18.255.254176.18.255.25532,766
39176.19.0.0/17176.19.0.1 to 176.19.127.254176.19.127.25532,766
40176.19.128.0/17176.19.128.1 to 176.19.255.254176.19.255.25532,766
41176.20.0.0/17176.20.0.1 to 176.20.127.254176.20.127.25532,766
42176.20.128.0/17176.20.128.1 to 176.20.255.254176.20.255.25532,766
43176.21.0.0/17176.21.0.1 to 176.21.127.254176.21.127.25532,766
44176.21.128.0/17176.21.128.1 to 176.21.255.254176.21.255.25532,766
45176.22.0.0/17176.22.0.1 to 176.22.127.254176.22.127.25532,766
46176.22.128.0/17176.22.128.1 to 176.22.255.254176.22.255.25532,766
47176.23.0.0/17176.23.0.1 to 176.23.127.254176.23.127.25532,766
48176.23.128.0/17176.23.128.1 to 176.23.255.254176.23.255.25532,766
49176.24.0.0/17176.24.0.1 to 176.24.127.254176.24.127.25532,766
50176.24.128.0/17176.24.128.1 to 176.24.255.254176.24.255.25532,766
51176.25.0.0/17176.25.0.1 to 176.25.127.254176.25.127.25532,766
52176.25.128.0/17176.25.128.1 to 176.25.255.254176.25.255.25532,766
53176.26.0.0/17176.26.0.1 to 176.26.127.254176.26.127.25532,766
54176.26.128.0/17176.26.128.1 to 176.26.255.254176.26.255.25532,766
55176.27.0.0/17176.27.0.1 to 176.27.127.254176.27.127.25532,766
56176.27.128.0/17176.27.128.1 to 176.27.255.254176.27.255.25532,766
57176.28.0.0/17176.28.0.1 to 176.28.127.254176.28.127.25532,766
58176.28.128.0/17176.28.128.1 to 176.28.255.254176.28.255.25532,766
59176.29.0.0/17176.29.0.1 to 176.29.127.254176.29.127.25532,766
60176.29.128.0/17176.29.128.1 to 176.29.255.254176.29.255.25532,766
61176.30.0.0/17176.30.0.1 to 176.30.127.254176.30.127.25532,766
62176.30.128.0/17176.30.128.1 to 176.30.255.254176.30.255.25532,766
63176.31.0.0/17176.31.0.1 to 176.31.127.254176.31.127.25532,766
64176.31.128.0/17176.31.128.1 to 176.31.255.254176.31.255.25532,766
65176.32.0.0/17176.32.0.1 to 176.32.127.254176.32.127.25532,766
66176.32.128.0/17176.32.128.1 to 176.32.255.254176.32.255.25532,766
67176.33.0.0/17176.33.0.1 to 176.33.127.254176.33.127.25532,766
68176.33.128.0/17176.33.128.1 to 176.33.255.254176.33.255.25532,766
69176.34.0.0/17176.34.0.1 to 176.34.127.254176.34.127.25532,766
70176.34.128.0/17176.34.128.1 to 176.34.255.254176.34.255.25532,766
71176.35.0.0/17176.35.0.1 to 176.35.127.254176.35.127.25532,766
72176.35.128.0/17176.35.128.1 to 176.35.255.254176.35.255.25532,766
73176.36.0.0/17176.36.0.1 to 176.36.127.254176.36.127.25532,766
74176.36.128.0/17176.36.128.1 to 176.36.255.254176.36.255.25532,766
75176.37.0.0/17176.37.0.1 to 176.37.127.254176.37.127.25532,766
76176.37.128.0/17176.37.128.1 to 176.37.255.254176.37.255.25532,766
77176.38.0.0/17176.38.0.1 to 176.38.127.254176.38.127.25532,766
78176.38.128.0/17176.38.128.1 to 176.38.255.254176.38.255.25532,766
79176.39.0.0/17176.39.0.1 to 176.39.127.254176.39.127.25532,766
80176.39.128.0/17176.39.128.1 to 176.39.255.254176.39.255.25532,766
81176.40.0.0/17176.40.0.1 to 176.40.127.254176.40.127.25532,766
82176.40.128.0/17176.40.128.1 to 176.40.255.254176.40.255.25532,766
83176.41.0.0/17176.41.0.1 to 176.41.127.254176.41.127.25532,766
84176.41.128.0/17176.41.128.1 to 176.41.255.254176.41.255.25532,766
85176.42.0.0/17176.42.0.1 to 176.42.127.254176.42.127.25532,766
86176.42.128.0/17176.42.128.1 to 176.42.255.254176.42.255.25532,766
87176.43.0.0/17176.43.0.1 to 176.43.127.254176.43.127.25532,766
88176.43.128.0/17176.43.128.1 to 176.43.255.254176.43.255.25532,766
89176.44.0.0/17176.44.0.1 to 176.44.127.254176.44.127.25532,766
90176.44.128.0/17176.44.128.1 to 176.44.255.254176.44.255.25532,766
91176.45.0.0/17176.45.0.1 to 176.45.127.254176.45.127.25532,766
92176.45.128.0/17176.45.128.1 to 176.45.255.254176.45.255.25532,766
93176.46.0.0/17176.46.0.1 to 176.46.127.254176.46.127.25532,766
94176.46.128.0/17176.46.128.1 to 176.46.255.254176.46.255.25532,766
95176.47.0.0/17176.47.0.1 to 176.47.127.254176.47.127.25532,766
96176.47.128.0/17176.47.128.1 to 176.47.255.254176.47.255.25532,766
97176.48.0.0/17176.48.0.1 to 176.48.127.254176.48.127.25532,766
98176.48.128.0/17176.48.128.1 to 176.48.255.254176.48.255.25532,766
99176.49.0.0/17176.49.0.1 to 176.49.127.254176.49.127.25532,766
100176.49.128.0/17176.49.128.1 to 176.49.255.254176.49.255.25532,766
101176.50.0.0/17176.50.0.1 to 176.50.127.254176.50.127.25532,766
102176.50.128.0/17176.50.128.1 to 176.50.255.254176.50.255.25532,766
103176.51.0.0/17176.51.0.1 to 176.51.127.254176.51.127.25532,766
104176.51.128.0/17176.51.128.1 to 176.51.255.254176.51.255.25532,766
105176.52.0.0/17176.52.0.1 to 176.52.127.254176.52.127.25532,766
106176.52.128.0/17176.52.128.1 to 176.52.255.254176.52.255.25532,766
107176.53.0.0/17176.53.0.1 to 176.53.127.254176.53.127.25532,766
108176.53.128.0/17176.53.128.1 to 176.53.255.254176.53.255.25532,766
109176.54.0.0/17176.54.0.1 to 176.54.127.254176.54.127.25532,766
110176.54.128.0/17176.54.128.1 to 176.54.255.254176.54.255.25532,766
111176.55.0.0/17176.55.0.1 to 176.55.127.254176.55.127.25532,766
112176.55.128.0/17176.55.128.1 to 176.55.255.254176.55.255.25532,766
113176.56.0.0/17176.56.0.1 to 176.56.127.254176.56.127.25532,766
114176.56.128.0/17176.56.128.1 to 176.56.255.254176.56.255.25532,766
115176.57.0.0/17176.57.0.1 to 176.57.127.254176.57.127.25532,766
116176.57.128.0/17176.57.128.1 to 176.57.255.254176.57.255.25532,766
117176.58.0.0/17176.58.0.1 to 176.58.127.254176.58.127.25532,766
118176.58.128.0/17176.58.128.1 to 176.58.255.254176.58.255.25532,766
119176.59.0.0/17176.59.0.1 to 176.59.127.254176.59.127.25532,766
120176.59.128.0/17176.59.128.1 to 176.59.255.254176.59.255.25532,766
121176.60.0.0/17176.60.0.1 to 176.60.127.254176.60.127.25532,766
122176.60.128.0/17176.60.128.1 to 176.60.255.254176.60.255.25532,766
123176.61.0.0/17176.61.0.1 to 176.61.127.254176.61.127.25532,766
124176.61.128.0/17176.61.128.1 to 176.61.255.254176.61.255.25532,766
125176.62.0.0/17176.62.0.1 to 176.62.127.254176.62.127.25532,766
126176.62.128.0/17176.62.128.1 to 176.62.255.254176.62.255.25532,766
127176.63.0.0/17176.63.0.1 to 176.63.127.254176.63.127.25532,766
128176.63.128.0/17176.63.128.1 to 176.63.255.254176.63.255.25532,766
129176.64.0.0/17176.64.0.1 to 176.64.127.254176.64.127.25532,766
130176.64.128.0/17176.64.128.1 to 176.64.255.254176.64.255.25532,766
131176.65.0.0/17176.65.0.1 to 176.65.127.254176.65.127.25532,766
132176.65.128.0/17176.65.128.1 to 176.65.255.254176.65.255.25532,766
133176.66.0.0/17176.66.0.1 to 176.66.127.254176.66.127.25532,766
134176.66.128.0/17176.66.128.1 to 176.66.255.254176.66.255.25532,766
135176.67.0.0/17176.67.0.1 to 176.67.127.254176.67.127.25532,766
136176.67.128.0/17176.67.128.1 to 176.67.255.254176.67.255.25532,766
137176.68.0.0/17176.68.0.1 to 176.68.127.254176.68.127.25532,766
138176.68.128.0/17176.68.128.1 to 176.68.255.254176.68.255.25532,766
139176.69.0.0/17176.69.0.1 to 176.69.127.254176.69.127.25532,766
140176.69.128.0/17176.69.128.1 to 176.69.255.254176.69.255.25532,766
141176.70.0.0/17176.70.0.1 to 176.70.127.254176.70.127.25532,766
142176.70.128.0/17176.70.128.1 to 176.70.255.254176.70.255.25532,766
143176.71.0.0/17176.71.0.1 to 176.71.127.254176.71.127.25532,766
144176.71.128.0/17176.71.128.1 to 176.71.255.254176.71.255.25532,766
145176.72.0.0/17176.72.0.1 to 176.72.127.254176.72.127.25532,766
146176.72.128.0/17176.72.128.1 to 176.72.255.254176.72.255.25532,766
147176.73.0.0/17176.73.0.1 to 176.73.127.254176.73.127.25532,766
148176.73.128.0/17176.73.128.1 to 176.73.255.254176.73.255.25532,766
149176.74.0.0/17176.74.0.1 to 176.74.127.254176.74.127.25532,766
150176.74.128.0/17176.74.128.1 to 176.74.255.254176.74.255.25532,766
151176.75.0.0/17176.75.0.1 to 176.75.127.254176.75.127.25532,766
152176.75.128.0/17176.75.128.1 to 176.75.255.254176.75.255.25532,766
153176.76.0.0/17176.76.0.1 to 176.76.127.254176.76.127.25532,766
154176.76.128.0/17176.76.128.1 to 176.76.255.254176.76.255.25532,766
155176.77.0.0/17176.77.0.1 to 176.77.127.254176.77.127.25532,766
156176.77.128.0/17176.77.128.1 to 176.77.255.254176.77.255.25532,766
157176.78.0.0/17176.78.0.1 to 176.78.127.254176.78.127.25532,766
158176.78.128.0/17176.78.128.1 to 176.78.255.254176.78.255.25532,766
159176.79.0.0/17176.79.0.1 to 176.79.127.254176.79.127.25532,766
160176.79.128.0/17176.79.128.1 to 176.79.255.254176.79.255.25532,766
161176.80.0.0/17176.80.0.1 to 176.80.127.254176.80.127.25532,766
162176.80.128.0/17176.80.128.1 to 176.80.255.254176.80.255.25532,766
163176.81.0.0/17176.81.0.1 to 176.81.127.254176.81.127.25532,766
164176.81.128.0/17176.81.128.1 to 176.81.255.254176.81.255.25532,766
165176.82.0.0/17176.82.0.1 to 176.82.127.254176.82.127.25532,766
166176.82.128.0/17176.82.128.1 to 176.82.255.254176.82.255.25532,766
167176.83.0.0/17176.83.0.1 to 176.83.127.254176.83.127.25532,766
168176.83.128.0/17176.83.128.1 to 176.83.255.254176.83.255.25532,766
169176.84.0.0/17176.84.0.1 to 176.84.127.254176.84.127.25532,766
170176.84.128.0/17176.84.128.1 to 176.84.255.254176.84.255.25532,766
171176.85.0.0/17176.85.0.1 to 176.85.127.254176.85.127.25532,766
172176.85.128.0/17176.85.128.1 to 176.85.255.254176.85.255.25532,766
173176.86.0.0/17176.86.0.1 to 176.86.127.254176.86.127.25532,766
174176.86.128.0/17176.86.128.1 to 176.86.255.254176.86.255.25532,766
175176.87.0.0/17176.87.0.1 to 176.87.127.254176.87.127.25532,766
176176.87.128.0/17176.87.128.1 to 176.87.255.254176.87.255.25532,766
177176.88.0.0/17176.88.0.1 to 176.88.127.254176.88.127.25532,766
178176.88.128.0/17176.88.128.1 to 176.88.255.254176.88.255.25532,766
179176.89.0.0/17176.89.0.1 to 176.89.127.254176.89.127.25532,766
180176.89.128.0/17176.89.128.1 to 176.89.255.254176.89.255.25532,766
181176.90.0.0/17176.90.0.1 to 176.90.127.254176.90.127.25532,766
182176.90.128.0/17176.90.128.1 to 176.90.255.254176.90.255.25532,766
183176.91.0.0/17176.91.0.1 to 176.91.127.254176.91.127.25532,766
184176.91.128.0/17176.91.128.1 to 176.91.255.254176.91.255.25532,766
185176.92.0.0/17176.92.0.1 to 176.92.127.254176.92.127.25532,766
186176.92.128.0/17176.92.128.1 to 176.92.255.254176.92.255.25532,766
187176.93.0.0/17176.93.0.1 to 176.93.127.254176.93.127.25532,766
188176.93.128.0/17176.93.128.1 to 176.93.255.254176.93.255.25532,766
189176.94.0.0/17176.94.0.1 to 176.94.127.254176.94.127.25532,766
190176.94.128.0/17176.94.128.1 to 176.94.255.254176.94.255.25532,766
191176.95.0.0/17176.95.0.1 to 176.95.127.254176.95.127.25532,766
192176.95.128.0/17176.95.128.1 to 176.95.255.254176.95.255.25532,766
193176.96.0.0/17176.96.0.1 to 176.96.127.254176.96.127.25532,766
194176.96.128.0/17176.96.128.1 to 176.96.255.254176.96.255.25532,766
195176.97.0.0/17176.97.0.1 to 176.97.127.254176.97.127.25532,766
196176.97.128.0/17176.97.128.1 to 176.97.255.254176.97.255.25532,766
197176.98.0.0/17176.98.0.1 to 176.98.127.254176.98.127.25532,766
198176.98.128.0/17176.98.128.1 to 176.98.255.254176.98.255.25532,766
199176.99.0.0/17176.99.0.1 to 176.99.127.254176.99.127.25532,766
200176.99.128.0/17176.99.128.1 to 176.99.255.254176.99.255.25532,766
201176.100.0.0/17176.100.0.1 to 176.100.127.254176.100.127.25532,766
202176.100.128.0/17176.100.128.1 to 176.100.255.254176.100.255.25532,766
203176.101.0.0/17176.101.0.1 to 176.101.127.254176.101.127.25532,766
204176.101.128.0/17176.101.128.1 to 176.101.255.254176.101.255.25532,766
205176.102.0.0/17176.102.0.1 to 176.102.127.254176.102.127.25532,766
206176.102.128.0/17176.102.128.1 to 176.102.255.254176.102.255.25532,766
207176.103.0.0/17176.103.0.1 to 176.103.127.254176.103.127.25532,766
208176.103.128.0/17176.103.128.1 to 176.103.255.254176.103.255.25532,766
209176.104.0.0/17176.104.0.1 to 176.104.127.254176.104.127.25532,766
210176.104.128.0/17176.104.128.1 to 176.104.255.254176.104.255.25532,766
211176.105.0.0/17176.105.0.1 to 176.105.127.254176.105.127.25532,766
212176.105.128.0/17176.105.128.1 to 176.105.255.254176.105.255.25532,766
213176.106.0.0/17176.106.0.1 to 176.106.127.254176.106.127.25532,766
214176.106.128.0/17176.106.128.1 to 176.106.255.254176.106.255.25532,766
215176.107.0.0/17176.107.0.1 to 176.107.127.254176.107.127.25532,766
216176.107.128.0/17176.107.128.1 to 176.107.255.254176.107.255.25532,766
217176.108.0.0/17176.108.0.1 to 176.108.127.254176.108.127.25532,766
218176.108.128.0/17176.108.128.1 to 176.108.255.254176.108.255.25532,766
219176.109.0.0/17176.109.0.1 to 176.109.127.254176.109.127.25532,766
220176.109.128.0/17176.109.128.1 to 176.109.255.254176.109.255.25532,766
221176.110.0.0/17176.110.0.1 to 176.110.127.254176.110.127.25532,766
222176.110.128.0/17176.110.128.1 to 176.110.255.254176.110.255.25532,766
223176.111.0.0/17176.111.0.1 to 176.111.127.254176.111.127.25532,766
224176.111.128.0/17176.111.128.1 to 176.111.255.254176.111.255.25532,766
225176.112.0.0/17176.112.0.1 to 176.112.127.254176.112.127.25532,766
226176.112.128.0/17176.112.128.1 to 176.112.255.254176.112.255.25532,766
227176.113.0.0/17176.113.0.1 to 176.113.127.254176.113.127.25532,766
228176.113.128.0/17176.113.128.1 to 176.113.255.254176.113.255.25532,766
229176.114.0.0/17176.114.0.1 to 176.114.127.254176.114.127.25532,766
230176.114.128.0/17176.114.128.1 to 176.114.255.254176.114.255.25532,766
231176.115.0.0/17176.115.0.1 to 176.115.127.254176.115.127.25532,766
232176.115.128.0/17176.115.128.1 to 176.115.255.254176.115.255.25532,766
233176.116.0.0/17176.116.0.1 to 176.116.127.254176.116.127.25532,766
234176.116.128.0/17176.116.128.1 to 176.116.255.254176.116.255.25532,766
235176.117.0.0/17176.117.0.1 to 176.117.127.254176.117.127.25532,766
236176.117.128.0/17176.117.128.1 to 176.117.255.254176.117.255.25532,766
237176.118.0.0/17176.118.0.1 to 176.118.127.254176.118.127.25532,766
238176.118.128.0/17176.118.128.1 to 176.118.255.254176.118.255.25532,766
239176.119.0.0/17176.119.0.1 to 176.119.127.254176.119.127.25532,766
240176.119.128.0/17176.119.128.1 to 176.119.255.254176.119.255.25532,766
241176.120.0.0/17176.120.0.1 to 176.120.127.254176.120.127.25532,766
242176.120.128.0/17176.120.128.1 to 176.120.255.254176.120.255.25532,766
243176.121.0.0/17176.121.0.1 to 176.121.127.254176.121.127.25532,766
244176.121.128.0/17176.121.128.1 to 176.121.255.254176.121.255.25532,766
245176.122.0.0/17176.122.0.1 to 176.122.127.254176.122.127.25532,766
246176.122.128.0/17176.122.128.1 to 176.122.255.254176.122.255.25532,766
247176.123.0.0/17176.123.0.1 to 176.123.127.254176.123.127.25532,766
248176.123.128.0/17176.123.128.1 to 176.123.255.254176.123.255.25532,766
249176.124.0.0/17176.124.0.1 to 176.124.127.254176.124.127.25532,766
250176.124.128.0/17176.124.128.1 to 176.124.255.254176.124.255.25532,766
251176.125.0.0/17176.125.0.1 to 176.125.127.254176.125.127.25532,766
252176.125.128.0/17176.125.128.1 to 176.125.255.254176.125.255.25532,766
253176.126.0.0/17176.126.0.1 to 176.126.127.254176.126.127.25532,766
254176.126.128.0/17176.126.128.1 to 176.126.255.254176.126.255.25532,766
255176.127.0.0/17176.127.0.1 to 176.127.127.254176.127.127.25532,766
256176.127.128.0/17176.127.128.1 to 176.127.255.254176.127.255.25532,766

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.