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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.

Network154.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
154.0.0.0
Broadcast address
154.255.255.255
First usable
154.0.0.1
Last usable
154.255.255.254
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 9A000000 · Integer 2583691264 to 2600468479
Reverse DNS zone
154.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10011010..00000000.00000000.00000000154.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10011010..00000000.00000000.00000000154.0.0.0
Broadcast10011010..11111111.11111111.11111111154.255.255.255
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)

154.0.0.0/8 makes 512 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1154.0.0.0/17154.0.0.1 to 154.0.127.254154.0.127.25532,766
2154.0.128.0/17154.0.128.1 to 154.0.255.254154.0.255.25532,766
3154.1.0.0/17154.1.0.1 to 154.1.127.254154.1.127.25532,766
4154.1.128.0/17154.1.128.1 to 154.1.255.254154.1.255.25532,766
5154.2.0.0/17154.2.0.1 to 154.2.127.254154.2.127.25532,766
6154.2.128.0/17154.2.128.1 to 154.2.255.254154.2.255.25532,766
7154.3.0.0/17154.3.0.1 to 154.3.127.254154.3.127.25532,766
8154.3.128.0/17154.3.128.1 to 154.3.255.254154.3.255.25532,766
9154.4.0.0/17154.4.0.1 to 154.4.127.254154.4.127.25532,766
10154.4.128.0/17154.4.128.1 to 154.4.255.254154.4.255.25532,766
11154.5.0.0/17154.5.0.1 to 154.5.127.254154.5.127.25532,766
12154.5.128.0/17154.5.128.1 to 154.5.255.254154.5.255.25532,766
13154.6.0.0/17154.6.0.1 to 154.6.127.254154.6.127.25532,766
14154.6.128.0/17154.6.128.1 to 154.6.255.254154.6.255.25532,766
15154.7.0.0/17154.7.0.1 to 154.7.127.254154.7.127.25532,766
16154.7.128.0/17154.7.128.1 to 154.7.255.254154.7.255.25532,766
17154.8.0.0/17154.8.0.1 to 154.8.127.254154.8.127.25532,766
18154.8.128.0/17154.8.128.1 to 154.8.255.254154.8.255.25532,766
19154.9.0.0/17154.9.0.1 to 154.9.127.254154.9.127.25532,766
20154.9.128.0/17154.9.128.1 to 154.9.255.254154.9.255.25532,766
21154.10.0.0/17154.10.0.1 to 154.10.127.254154.10.127.25532,766
22154.10.128.0/17154.10.128.1 to 154.10.255.254154.10.255.25532,766
23154.11.0.0/17154.11.0.1 to 154.11.127.254154.11.127.25532,766
24154.11.128.0/17154.11.128.1 to 154.11.255.254154.11.255.25532,766
25154.12.0.0/17154.12.0.1 to 154.12.127.254154.12.127.25532,766
26154.12.128.0/17154.12.128.1 to 154.12.255.254154.12.255.25532,766
27154.13.0.0/17154.13.0.1 to 154.13.127.254154.13.127.25532,766
28154.13.128.0/17154.13.128.1 to 154.13.255.254154.13.255.25532,766
29154.14.0.0/17154.14.0.1 to 154.14.127.254154.14.127.25532,766
30154.14.128.0/17154.14.128.1 to 154.14.255.254154.14.255.25532,766
31154.15.0.0/17154.15.0.1 to 154.15.127.254154.15.127.25532,766
32154.15.128.0/17154.15.128.1 to 154.15.255.254154.15.255.25532,766
33154.16.0.0/17154.16.0.1 to 154.16.127.254154.16.127.25532,766
34154.16.128.0/17154.16.128.1 to 154.16.255.254154.16.255.25532,766
35154.17.0.0/17154.17.0.1 to 154.17.127.254154.17.127.25532,766
36154.17.128.0/17154.17.128.1 to 154.17.255.254154.17.255.25532,766
37154.18.0.0/17154.18.0.1 to 154.18.127.254154.18.127.25532,766
38154.18.128.0/17154.18.128.1 to 154.18.255.254154.18.255.25532,766
39154.19.0.0/17154.19.0.1 to 154.19.127.254154.19.127.25532,766
40154.19.128.0/17154.19.128.1 to 154.19.255.254154.19.255.25532,766
41154.20.0.0/17154.20.0.1 to 154.20.127.254154.20.127.25532,766
42154.20.128.0/17154.20.128.1 to 154.20.255.254154.20.255.25532,766
43154.21.0.0/17154.21.0.1 to 154.21.127.254154.21.127.25532,766
44154.21.128.0/17154.21.128.1 to 154.21.255.254154.21.255.25532,766
45154.22.0.0/17154.22.0.1 to 154.22.127.254154.22.127.25532,766
46154.22.128.0/17154.22.128.1 to 154.22.255.254154.22.255.25532,766
47154.23.0.0/17154.23.0.1 to 154.23.127.254154.23.127.25532,766
48154.23.128.0/17154.23.128.1 to 154.23.255.254154.23.255.25532,766
49154.24.0.0/17154.24.0.1 to 154.24.127.254154.24.127.25532,766
50154.24.128.0/17154.24.128.1 to 154.24.255.254154.24.255.25532,766
51154.25.0.0/17154.25.0.1 to 154.25.127.254154.25.127.25532,766
52154.25.128.0/17154.25.128.1 to 154.25.255.254154.25.255.25532,766
53154.26.0.0/17154.26.0.1 to 154.26.127.254154.26.127.25532,766
54154.26.128.0/17154.26.128.1 to 154.26.255.254154.26.255.25532,766
55154.27.0.0/17154.27.0.1 to 154.27.127.254154.27.127.25532,766
56154.27.128.0/17154.27.128.1 to 154.27.255.254154.27.255.25532,766
57154.28.0.0/17154.28.0.1 to 154.28.127.254154.28.127.25532,766
58154.28.128.0/17154.28.128.1 to 154.28.255.254154.28.255.25532,766
59154.29.0.0/17154.29.0.1 to 154.29.127.254154.29.127.25532,766
60154.29.128.0/17154.29.128.1 to 154.29.255.254154.29.255.25532,766
61154.30.0.0/17154.30.0.1 to 154.30.127.254154.30.127.25532,766
62154.30.128.0/17154.30.128.1 to 154.30.255.254154.30.255.25532,766
63154.31.0.0/17154.31.0.1 to 154.31.127.254154.31.127.25532,766
64154.31.128.0/17154.31.128.1 to 154.31.255.254154.31.255.25532,766
65154.32.0.0/17154.32.0.1 to 154.32.127.254154.32.127.25532,766
66154.32.128.0/17154.32.128.1 to 154.32.255.254154.32.255.25532,766
67154.33.0.0/17154.33.0.1 to 154.33.127.254154.33.127.25532,766
68154.33.128.0/17154.33.128.1 to 154.33.255.254154.33.255.25532,766
69154.34.0.0/17154.34.0.1 to 154.34.127.254154.34.127.25532,766
70154.34.128.0/17154.34.128.1 to 154.34.255.254154.34.255.25532,766
71154.35.0.0/17154.35.0.1 to 154.35.127.254154.35.127.25532,766
72154.35.128.0/17154.35.128.1 to 154.35.255.254154.35.255.25532,766
73154.36.0.0/17154.36.0.1 to 154.36.127.254154.36.127.25532,766
74154.36.128.0/17154.36.128.1 to 154.36.255.254154.36.255.25532,766
75154.37.0.0/17154.37.0.1 to 154.37.127.254154.37.127.25532,766
76154.37.128.0/17154.37.128.1 to 154.37.255.254154.37.255.25532,766
77154.38.0.0/17154.38.0.1 to 154.38.127.254154.38.127.25532,766
78154.38.128.0/17154.38.128.1 to 154.38.255.254154.38.255.25532,766
79154.39.0.0/17154.39.0.1 to 154.39.127.254154.39.127.25532,766
80154.39.128.0/17154.39.128.1 to 154.39.255.254154.39.255.25532,766
81154.40.0.0/17154.40.0.1 to 154.40.127.254154.40.127.25532,766
82154.40.128.0/17154.40.128.1 to 154.40.255.254154.40.255.25532,766
83154.41.0.0/17154.41.0.1 to 154.41.127.254154.41.127.25532,766
84154.41.128.0/17154.41.128.1 to 154.41.255.254154.41.255.25532,766
85154.42.0.0/17154.42.0.1 to 154.42.127.254154.42.127.25532,766
86154.42.128.0/17154.42.128.1 to 154.42.255.254154.42.255.25532,766
87154.43.0.0/17154.43.0.1 to 154.43.127.254154.43.127.25532,766
88154.43.128.0/17154.43.128.1 to 154.43.255.254154.43.255.25532,766
89154.44.0.0/17154.44.0.1 to 154.44.127.254154.44.127.25532,766
90154.44.128.0/17154.44.128.1 to 154.44.255.254154.44.255.25532,766
91154.45.0.0/17154.45.0.1 to 154.45.127.254154.45.127.25532,766
92154.45.128.0/17154.45.128.1 to 154.45.255.254154.45.255.25532,766
93154.46.0.0/17154.46.0.1 to 154.46.127.254154.46.127.25532,766
94154.46.128.0/17154.46.128.1 to 154.46.255.254154.46.255.25532,766
95154.47.0.0/17154.47.0.1 to 154.47.127.254154.47.127.25532,766
96154.47.128.0/17154.47.128.1 to 154.47.255.254154.47.255.25532,766
97154.48.0.0/17154.48.0.1 to 154.48.127.254154.48.127.25532,766
98154.48.128.0/17154.48.128.1 to 154.48.255.254154.48.255.25532,766
99154.49.0.0/17154.49.0.1 to 154.49.127.254154.49.127.25532,766
100154.49.128.0/17154.49.128.1 to 154.49.255.254154.49.255.25532,766
101154.50.0.0/17154.50.0.1 to 154.50.127.254154.50.127.25532,766
102154.50.128.0/17154.50.128.1 to 154.50.255.254154.50.255.25532,766
103154.51.0.0/17154.51.0.1 to 154.51.127.254154.51.127.25532,766
104154.51.128.0/17154.51.128.1 to 154.51.255.254154.51.255.25532,766
105154.52.0.0/17154.52.0.1 to 154.52.127.254154.52.127.25532,766
106154.52.128.0/17154.52.128.1 to 154.52.255.254154.52.255.25532,766
107154.53.0.0/17154.53.0.1 to 154.53.127.254154.53.127.25532,766
108154.53.128.0/17154.53.128.1 to 154.53.255.254154.53.255.25532,766
109154.54.0.0/17154.54.0.1 to 154.54.127.254154.54.127.25532,766
110154.54.128.0/17154.54.128.1 to 154.54.255.254154.54.255.25532,766
111154.55.0.0/17154.55.0.1 to 154.55.127.254154.55.127.25532,766
112154.55.128.0/17154.55.128.1 to 154.55.255.254154.55.255.25532,766
113154.56.0.0/17154.56.0.1 to 154.56.127.254154.56.127.25532,766
114154.56.128.0/17154.56.128.1 to 154.56.255.254154.56.255.25532,766
115154.57.0.0/17154.57.0.1 to 154.57.127.254154.57.127.25532,766
116154.57.128.0/17154.57.128.1 to 154.57.255.254154.57.255.25532,766
117154.58.0.0/17154.58.0.1 to 154.58.127.254154.58.127.25532,766
118154.58.128.0/17154.58.128.1 to 154.58.255.254154.58.255.25532,766
119154.59.0.0/17154.59.0.1 to 154.59.127.254154.59.127.25532,766
120154.59.128.0/17154.59.128.1 to 154.59.255.254154.59.255.25532,766
121154.60.0.0/17154.60.0.1 to 154.60.127.254154.60.127.25532,766
122154.60.128.0/17154.60.128.1 to 154.60.255.254154.60.255.25532,766
123154.61.0.0/17154.61.0.1 to 154.61.127.254154.61.127.25532,766
124154.61.128.0/17154.61.128.1 to 154.61.255.254154.61.255.25532,766
125154.62.0.0/17154.62.0.1 to 154.62.127.254154.62.127.25532,766
126154.62.128.0/17154.62.128.1 to 154.62.255.254154.62.255.25532,766
127154.63.0.0/17154.63.0.1 to 154.63.127.254154.63.127.25532,766
128154.63.128.0/17154.63.128.1 to 154.63.255.254154.63.255.25532,766
129154.64.0.0/17154.64.0.1 to 154.64.127.254154.64.127.25532,766
130154.64.128.0/17154.64.128.1 to 154.64.255.254154.64.255.25532,766
131154.65.0.0/17154.65.0.1 to 154.65.127.254154.65.127.25532,766
132154.65.128.0/17154.65.128.1 to 154.65.255.254154.65.255.25532,766
133154.66.0.0/17154.66.0.1 to 154.66.127.254154.66.127.25532,766
134154.66.128.0/17154.66.128.1 to 154.66.255.254154.66.255.25532,766
135154.67.0.0/17154.67.0.1 to 154.67.127.254154.67.127.25532,766
136154.67.128.0/17154.67.128.1 to 154.67.255.254154.67.255.25532,766
137154.68.0.0/17154.68.0.1 to 154.68.127.254154.68.127.25532,766
138154.68.128.0/17154.68.128.1 to 154.68.255.254154.68.255.25532,766
139154.69.0.0/17154.69.0.1 to 154.69.127.254154.69.127.25532,766
140154.69.128.0/17154.69.128.1 to 154.69.255.254154.69.255.25532,766
141154.70.0.0/17154.70.0.1 to 154.70.127.254154.70.127.25532,766
142154.70.128.0/17154.70.128.1 to 154.70.255.254154.70.255.25532,766
143154.71.0.0/17154.71.0.1 to 154.71.127.254154.71.127.25532,766
144154.71.128.0/17154.71.128.1 to 154.71.255.254154.71.255.25532,766
145154.72.0.0/17154.72.0.1 to 154.72.127.254154.72.127.25532,766
146154.72.128.0/17154.72.128.1 to 154.72.255.254154.72.255.25532,766
147154.73.0.0/17154.73.0.1 to 154.73.127.254154.73.127.25532,766
148154.73.128.0/17154.73.128.1 to 154.73.255.254154.73.255.25532,766
149154.74.0.0/17154.74.0.1 to 154.74.127.254154.74.127.25532,766
150154.74.128.0/17154.74.128.1 to 154.74.255.254154.74.255.25532,766
151154.75.0.0/17154.75.0.1 to 154.75.127.254154.75.127.25532,766
152154.75.128.0/17154.75.128.1 to 154.75.255.254154.75.255.25532,766
153154.76.0.0/17154.76.0.1 to 154.76.127.254154.76.127.25532,766
154154.76.128.0/17154.76.128.1 to 154.76.255.254154.76.255.25532,766
155154.77.0.0/17154.77.0.1 to 154.77.127.254154.77.127.25532,766
156154.77.128.0/17154.77.128.1 to 154.77.255.254154.77.255.25532,766
157154.78.0.0/17154.78.0.1 to 154.78.127.254154.78.127.25532,766
158154.78.128.0/17154.78.128.1 to 154.78.255.254154.78.255.25532,766
159154.79.0.0/17154.79.0.1 to 154.79.127.254154.79.127.25532,766
160154.79.128.0/17154.79.128.1 to 154.79.255.254154.79.255.25532,766
161154.80.0.0/17154.80.0.1 to 154.80.127.254154.80.127.25532,766
162154.80.128.0/17154.80.128.1 to 154.80.255.254154.80.255.25532,766
163154.81.0.0/17154.81.0.1 to 154.81.127.254154.81.127.25532,766
164154.81.128.0/17154.81.128.1 to 154.81.255.254154.81.255.25532,766
165154.82.0.0/17154.82.0.1 to 154.82.127.254154.82.127.25532,766
166154.82.128.0/17154.82.128.1 to 154.82.255.254154.82.255.25532,766
167154.83.0.0/17154.83.0.1 to 154.83.127.254154.83.127.25532,766
168154.83.128.0/17154.83.128.1 to 154.83.255.254154.83.255.25532,766
169154.84.0.0/17154.84.0.1 to 154.84.127.254154.84.127.25532,766
170154.84.128.0/17154.84.128.1 to 154.84.255.254154.84.255.25532,766
171154.85.0.0/17154.85.0.1 to 154.85.127.254154.85.127.25532,766
172154.85.128.0/17154.85.128.1 to 154.85.255.254154.85.255.25532,766
173154.86.0.0/17154.86.0.1 to 154.86.127.254154.86.127.25532,766
174154.86.128.0/17154.86.128.1 to 154.86.255.254154.86.255.25532,766
175154.87.0.0/17154.87.0.1 to 154.87.127.254154.87.127.25532,766
176154.87.128.0/17154.87.128.1 to 154.87.255.254154.87.255.25532,766
177154.88.0.0/17154.88.0.1 to 154.88.127.254154.88.127.25532,766
178154.88.128.0/17154.88.128.1 to 154.88.255.254154.88.255.25532,766
179154.89.0.0/17154.89.0.1 to 154.89.127.254154.89.127.25532,766
180154.89.128.0/17154.89.128.1 to 154.89.255.254154.89.255.25532,766
181154.90.0.0/17154.90.0.1 to 154.90.127.254154.90.127.25532,766
182154.90.128.0/17154.90.128.1 to 154.90.255.254154.90.255.25532,766
183154.91.0.0/17154.91.0.1 to 154.91.127.254154.91.127.25532,766
184154.91.128.0/17154.91.128.1 to 154.91.255.254154.91.255.25532,766
185154.92.0.0/17154.92.0.1 to 154.92.127.254154.92.127.25532,766
186154.92.128.0/17154.92.128.1 to 154.92.255.254154.92.255.25532,766
187154.93.0.0/17154.93.0.1 to 154.93.127.254154.93.127.25532,766
188154.93.128.0/17154.93.128.1 to 154.93.255.254154.93.255.25532,766
189154.94.0.0/17154.94.0.1 to 154.94.127.254154.94.127.25532,766
190154.94.128.0/17154.94.128.1 to 154.94.255.254154.94.255.25532,766
191154.95.0.0/17154.95.0.1 to 154.95.127.254154.95.127.25532,766
192154.95.128.0/17154.95.128.1 to 154.95.255.254154.95.255.25532,766
193154.96.0.0/17154.96.0.1 to 154.96.127.254154.96.127.25532,766
194154.96.128.0/17154.96.128.1 to 154.96.255.254154.96.255.25532,766
195154.97.0.0/17154.97.0.1 to 154.97.127.254154.97.127.25532,766
196154.97.128.0/17154.97.128.1 to 154.97.255.254154.97.255.25532,766
197154.98.0.0/17154.98.0.1 to 154.98.127.254154.98.127.25532,766
198154.98.128.0/17154.98.128.1 to 154.98.255.254154.98.255.25532,766
199154.99.0.0/17154.99.0.1 to 154.99.127.254154.99.127.25532,766
200154.99.128.0/17154.99.128.1 to 154.99.255.254154.99.255.25532,766
201154.100.0.0/17154.100.0.1 to 154.100.127.254154.100.127.25532,766
202154.100.128.0/17154.100.128.1 to 154.100.255.254154.100.255.25532,766
203154.101.0.0/17154.101.0.1 to 154.101.127.254154.101.127.25532,766
204154.101.128.0/17154.101.128.1 to 154.101.255.254154.101.255.25532,766
205154.102.0.0/17154.102.0.1 to 154.102.127.254154.102.127.25532,766
206154.102.128.0/17154.102.128.1 to 154.102.255.254154.102.255.25532,766
207154.103.0.0/17154.103.0.1 to 154.103.127.254154.103.127.25532,766
208154.103.128.0/17154.103.128.1 to 154.103.255.254154.103.255.25532,766
209154.104.0.0/17154.104.0.1 to 154.104.127.254154.104.127.25532,766
210154.104.128.0/17154.104.128.1 to 154.104.255.254154.104.255.25532,766
211154.105.0.0/17154.105.0.1 to 154.105.127.254154.105.127.25532,766
212154.105.128.0/17154.105.128.1 to 154.105.255.254154.105.255.25532,766
213154.106.0.0/17154.106.0.1 to 154.106.127.254154.106.127.25532,766
214154.106.128.0/17154.106.128.1 to 154.106.255.254154.106.255.25532,766
215154.107.0.0/17154.107.0.1 to 154.107.127.254154.107.127.25532,766
216154.107.128.0/17154.107.128.1 to 154.107.255.254154.107.255.25532,766
217154.108.0.0/17154.108.0.1 to 154.108.127.254154.108.127.25532,766
218154.108.128.0/17154.108.128.1 to 154.108.255.254154.108.255.25532,766
219154.109.0.0/17154.109.0.1 to 154.109.127.254154.109.127.25532,766
220154.109.128.0/17154.109.128.1 to 154.109.255.254154.109.255.25532,766
221154.110.0.0/17154.110.0.1 to 154.110.127.254154.110.127.25532,766
222154.110.128.0/17154.110.128.1 to 154.110.255.254154.110.255.25532,766
223154.111.0.0/17154.111.0.1 to 154.111.127.254154.111.127.25532,766
224154.111.128.0/17154.111.128.1 to 154.111.255.254154.111.255.25532,766
225154.112.0.0/17154.112.0.1 to 154.112.127.254154.112.127.25532,766
226154.112.128.0/17154.112.128.1 to 154.112.255.254154.112.255.25532,766
227154.113.0.0/17154.113.0.1 to 154.113.127.254154.113.127.25532,766
228154.113.128.0/17154.113.128.1 to 154.113.255.254154.113.255.25532,766
229154.114.0.0/17154.114.0.1 to 154.114.127.254154.114.127.25532,766
230154.114.128.0/17154.114.128.1 to 154.114.255.254154.114.255.25532,766
231154.115.0.0/17154.115.0.1 to 154.115.127.254154.115.127.25532,766
232154.115.128.0/17154.115.128.1 to 154.115.255.254154.115.255.25532,766
233154.116.0.0/17154.116.0.1 to 154.116.127.254154.116.127.25532,766
234154.116.128.0/17154.116.128.1 to 154.116.255.254154.116.255.25532,766
235154.117.0.0/17154.117.0.1 to 154.117.127.254154.117.127.25532,766
236154.117.128.0/17154.117.128.1 to 154.117.255.254154.117.255.25532,766
237154.118.0.0/17154.118.0.1 to 154.118.127.254154.118.127.25532,766
238154.118.128.0/17154.118.128.1 to 154.118.255.254154.118.255.25532,766
239154.119.0.0/17154.119.0.1 to 154.119.127.254154.119.127.25532,766
240154.119.128.0/17154.119.128.1 to 154.119.255.254154.119.255.25532,766
241154.120.0.0/17154.120.0.1 to 154.120.127.254154.120.127.25532,766
242154.120.128.0/17154.120.128.1 to 154.120.255.254154.120.255.25532,766
243154.121.0.0/17154.121.0.1 to 154.121.127.254154.121.127.25532,766
244154.121.128.0/17154.121.128.1 to 154.121.255.254154.121.255.25532,766
245154.122.0.0/17154.122.0.1 to 154.122.127.254154.122.127.25532,766
246154.122.128.0/17154.122.128.1 to 154.122.255.254154.122.255.25532,766
247154.123.0.0/17154.123.0.1 to 154.123.127.254154.123.127.25532,766
248154.123.128.0/17154.123.128.1 to 154.123.255.254154.123.255.25532,766
249154.124.0.0/17154.124.0.1 to 154.124.127.254154.124.127.25532,766
250154.124.128.0/17154.124.128.1 to 154.124.255.254154.124.255.25532,766
251154.125.0.0/17154.125.0.1 to 154.125.127.254154.125.127.25532,766
252154.125.128.0/17154.125.128.1 to 154.125.255.254154.125.255.25532,766
253154.126.0.0/17154.126.0.1 to 154.126.127.254154.126.127.25532,766
254154.126.128.0/17154.126.128.1 to 154.126.255.254154.126.255.25532,766
255154.127.0.0/17154.127.0.1 to 154.127.127.254154.127.127.25532,766
256154.127.128.0/17154.127.128.1 to 154.127.255.254154.127.255.25532,766

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.