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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.

Network135.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
135.0.0.0
Broadcast address
135.255.255.255
First usable
135.0.0.1
Last usable
135.255.255.254
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 87000000 · Integer 2264924160 to 2281701375
Reverse DNS zone
135.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10000111..00000000.00000000.00000000135.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10000111..00000000.00000000.00000000135.0.0.0
Broadcast10000111..11111111.11111111.11111111135.255.255.255
Split into smaller subnets/18
/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)

135.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1135.0.0.0/18135.0.0.1 to 135.0.63.254135.0.63.25516,382
2135.0.64.0/18135.0.64.1 to 135.0.127.254135.0.127.25516,382
3135.0.128.0/18135.0.128.1 to 135.0.191.254135.0.191.25516,382
4135.0.192.0/18135.0.192.1 to 135.0.255.254135.0.255.25516,382
5135.1.0.0/18135.1.0.1 to 135.1.63.254135.1.63.25516,382
6135.1.64.0/18135.1.64.1 to 135.1.127.254135.1.127.25516,382
7135.1.128.0/18135.1.128.1 to 135.1.191.254135.1.191.25516,382
8135.1.192.0/18135.1.192.1 to 135.1.255.254135.1.255.25516,382
9135.2.0.0/18135.2.0.1 to 135.2.63.254135.2.63.25516,382
10135.2.64.0/18135.2.64.1 to 135.2.127.254135.2.127.25516,382
11135.2.128.0/18135.2.128.1 to 135.2.191.254135.2.191.25516,382
12135.2.192.0/18135.2.192.1 to 135.2.255.254135.2.255.25516,382
13135.3.0.0/18135.3.0.1 to 135.3.63.254135.3.63.25516,382
14135.3.64.0/18135.3.64.1 to 135.3.127.254135.3.127.25516,382
15135.3.128.0/18135.3.128.1 to 135.3.191.254135.3.191.25516,382
16135.3.192.0/18135.3.192.1 to 135.3.255.254135.3.255.25516,382
17135.4.0.0/18135.4.0.1 to 135.4.63.254135.4.63.25516,382
18135.4.64.0/18135.4.64.1 to 135.4.127.254135.4.127.25516,382
19135.4.128.0/18135.4.128.1 to 135.4.191.254135.4.191.25516,382
20135.4.192.0/18135.4.192.1 to 135.4.255.254135.4.255.25516,382
21135.5.0.0/18135.5.0.1 to 135.5.63.254135.5.63.25516,382
22135.5.64.0/18135.5.64.1 to 135.5.127.254135.5.127.25516,382
23135.5.128.0/18135.5.128.1 to 135.5.191.254135.5.191.25516,382
24135.5.192.0/18135.5.192.1 to 135.5.255.254135.5.255.25516,382
25135.6.0.0/18135.6.0.1 to 135.6.63.254135.6.63.25516,382
26135.6.64.0/18135.6.64.1 to 135.6.127.254135.6.127.25516,382
27135.6.128.0/18135.6.128.1 to 135.6.191.254135.6.191.25516,382
28135.6.192.0/18135.6.192.1 to 135.6.255.254135.6.255.25516,382
29135.7.0.0/18135.7.0.1 to 135.7.63.254135.7.63.25516,382
30135.7.64.0/18135.7.64.1 to 135.7.127.254135.7.127.25516,382
31135.7.128.0/18135.7.128.1 to 135.7.191.254135.7.191.25516,382
32135.7.192.0/18135.7.192.1 to 135.7.255.254135.7.255.25516,382
33135.8.0.0/18135.8.0.1 to 135.8.63.254135.8.63.25516,382
34135.8.64.0/18135.8.64.1 to 135.8.127.254135.8.127.25516,382
35135.8.128.0/18135.8.128.1 to 135.8.191.254135.8.191.25516,382
36135.8.192.0/18135.8.192.1 to 135.8.255.254135.8.255.25516,382
37135.9.0.0/18135.9.0.1 to 135.9.63.254135.9.63.25516,382
38135.9.64.0/18135.9.64.1 to 135.9.127.254135.9.127.25516,382
39135.9.128.0/18135.9.128.1 to 135.9.191.254135.9.191.25516,382
40135.9.192.0/18135.9.192.1 to 135.9.255.254135.9.255.25516,382
41135.10.0.0/18135.10.0.1 to 135.10.63.254135.10.63.25516,382
42135.10.64.0/18135.10.64.1 to 135.10.127.254135.10.127.25516,382
43135.10.128.0/18135.10.128.1 to 135.10.191.254135.10.191.25516,382
44135.10.192.0/18135.10.192.1 to 135.10.255.254135.10.255.25516,382
45135.11.0.0/18135.11.0.1 to 135.11.63.254135.11.63.25516,382
46135.11.64.0/18135.11.64.1 to 135.11.127.254135.11.127.25516,382
47135.11.128.0/18135.11.128.1 to 135.11.191.254135.11.191.25516,382
48135.11.192.0/18135.11.192.1 to 135.11.255.254135.11.255.25516,382
49135.12.0.0/18135.12.0.1 to 135.12.63.254135.12.63.25516,382
50135.12.64.0/18135.12.64.1 to 135.12.127.254135.12.127.25516,382
51135.12.128.0/18135.12.128.1 to 135.12.191.254135.12.191.25516,382
52135.12.192.0/18135.12.192.1 to 135.12.255.254135.12.255.25516,382
53135.13.0.0/18135.13.0.1 to 135.13.63.254135.13.63.25516,382
54135.13.64.0/18135.13.64.1 to 135.13.127.254135.13.127.25516,382
55135.13.128.0/18135.13.128.1 to 135.13.191.254135.13.191.25516,382
56135.13.192.0/18135.13.192.1 to 135.13.255.254135.13.255.25516,382
57135.14.0.0/18135.14.0.1 to 135.14.63.254135.14.63.25516,382
58135.14.64.0/18135.14.64.1 to 135.14.127.254135.14.127.25516,382
59135.14.128.0/18135.14.128.1 to 135.14.191.254135.14.191.25516,382
60135.14.192.0/18135.14.192.1 to 135.14.255.254135.14.255.25516,382
61135.15.0.0/18135.15.0.1 to 135.15.63.254135.15.63.25516,382
62135.15.64.0/18135.15.64.1 to 135.15.127.254135.15.127.25516,382
63135.15.128.0/18135.15.128.1 to 135.15.191.254135.15.191.25516,382
64135.15.192.0/18135.15.192.1 to 135.15.255.254135.15.255.25516,382
65135.16.0.0/18135.16.0.1 to 135.16.63.254135.16.63.25516,382
66135.16.64.0/18135.16.64.1 to 135.16.127.254135.16.127.25516,382
67135.16.128.0/18135.16.128.1 to 135.16.191.254135.16.191.25516,382
68135.16.192.0/18135.16.192.1 to 135.16.255.254135.16.255.25516,382
69135.17.0.0/18135.17.0.1 to 135.17.63.254135.17.63.25516,382
70135.17.64.0/18135.17.64.1 to 135.17.127.254135.17.127.25516,382
71135.17.128.0/18135.17.128.1 to 135.17.191.254135.17.191.25516,382
72135.17.192.0/18135.17.192.1 to 135.17.255.254135.17.255.25516,382
73135.18.0.0/18135.18.0.1 to 135.18.63.254135.18.63.25516,382
74135.18.64.0/18135.18.64.1 to 135.18.127.254135.18.127.25516,382
75135.18.128.0/18135.18.128.1 to 135.18.191.254135.18.191.25516,382
76135.18.192.0/18135.18.192.1 to 135.18.255.254135.18.255.25516,382
77135.19.0.0/18135.19.0.1 to 135.19.63.254135.19.63.25516,382
78135.19.64.0/18135.19.64.1 to 135.19.127.254135.19.127.25516,382
79135.19.128.0/18135.19.128.1 to 135.19.191.254135.19.191.25516,382
80135.19.192.0/18135.19.192.1 to 135.19.255.254135.19.255.25516,382
81135.20.0.0/18135.20.0.1 to 135.20.63.254135.20.63.25516,382
82135.20.64.0/18135.20.64.1 to 135.20.127.254135.20.127.25516,382
83135.20.128.0/18135.20.128.1 to 135.20.191.254135.20.191.25516,382
84135.20.192.0/18135.20.192.1 to 135.20.255.254135.20.255.25516,382
85135.21.0.0/18135.21.0.1 to 135.21.63.254135.21.63.25516,382
86135.21.64.0/18135.21.64.1 to 135.21.127.254135.21.127.25516,382
87135.21.128.0/18135.21.128.1 to 135.21.191.254135.21.191.25516,382
88135.21.192.0/18135.21.192.1 to 135.21.255.254135.21.255.25516,382
89135.22.0.0/18135.22.0.1 to 135.22.63.254135.22.63.25516,382
90135.22.64.0/18135.22.64.1 to 135.22.127.254135.22.127.25516,382
91135.22.128.0/18135.22.128.1 to 135.22.191.254135.22.191.25516,382
92135.22.192.0/18135.22.192.1 to 135.22.255.254135.22.255.25516,382
93135.23.0.0/18135.23.0.1 to 135.23.63.254135.23.63.25516,382
94135.23.64.0/18135.23.64.1 to 135.23.127.254135.23.127.25516,382
95135.23.128.0/18135.23.128.1 to 135.23.191.254135.23.191.25516,382
96135.23.192.0/18135.23.192.1 to 135.23.255.254135.23.255.25516,382
97135.24.0.0/18135.24.0.1 to 135.24.63.254135.24.63.25516,382
98135.24.64.0/18135.24.64.1 to 135.24.127.254135.24.127.25516,382
99135.24.128.0/18135.24.128.1 to 135.24.191.254135.24.191.25516,382
100135.24.192.0/18135.24.192.1 to 135.24.255.254135.24.255.25516,382
101135.25.0.0/18135.25.0.1 to 135.25.63.254135.25.63.25516,382
102135.25.64.0/18135.25.64.1 to 135.25.127.254135.25.127.25516,382
103135.25.128.0/18135.25.128.1 to 135.25.191.254135.25.191.25516,382
104135.25.192.0/18135.25.192.1 to 135.25.255.254135.25.255.25516,382
105135.26.0.0/18135.26.0.1 to 135.26.63.254135.26.63.25516,382
106135.26.64.0/18135.26.64.1 to 135.26.127.254135.26.127.25516,382
107135.26.128.0/18135.26.128.1 to 135.26.191.254135.26.191.25516,382
108135.26.192.0/18135.26.192.1 to 135.26.255.254135.26.255.25516,382
109135.27.0.0/18135.27.0.1 to 135.27.63.254135.27.63.25516,382
110135.27.64.0/18135.27.64.1 to 135.27.127.254135.27.127.25516,382
111135.27.128.0/18135.27.128.1 to 135.27.191.254135.27.191.25516,382
112135.27.192.0/18135.27.192.1 to 135.27.255.254135.27.255.25516,382
113135.28.0.0/18135.28.0.1 to 135.28.63.254135.28.63.25516,382
114135.28.64.0/18135.28.64.1 to 135.28.127.254135.28.127.25516,382
115135.28.128.0/18135.28.128.1 to 135.28.191.254135.28.191.25516,382
116135.28.192.0/18135.28.192.1 to 135.28.255.254135.28.255.25516,382
117135.29.0.0/18135.29.0.1 to 135.29.63.254135.29.63.25516,382
118135.29.64.0/18135.29.64.1 to 135.29.127.254135.29.127.25516,382
119135.29.128.0/18135.29.128.1 to 135.29.191.254135.29.191.25516,382
120135.29.192.0/18135.29.192.1 to 135.29.255.254135.29.255.25516,382
121135.30.0.0/18135.30.0.1 to 135.30.63.254135.30.63.25516,382
122135.30.64.0/18135.30.64.1 to 135.30.127.254135.30.127.25516,382
123135.30.128.0/18135.30.128.1 to 135.30.191.254135.30.191.25516,382
124135.30.192.0/18135.30.192.1 to 135.30.255.254135.30.255.25516,382
125135.31.0.0/18135.31.0.1 to 135.31.63.254135.31.63.25516,382
126135.31.64.0/18135.31.64.1 to 135.31.127.254135.31.127.25516,382
127135.31.128.0/18135.31.128.1 to 135.31.191.254135.31.191.25516,382
128135.31.192.0/18135.31.192.1 to 135.31.255.254135.31.255.25516,382
129135.32.0.0/18135.32.0.1 to 135.32.63.254135.32.63.25516,382
130135.32.64.0/18135.32.64.1 to 135.32.127.254135.32.127.25516,382
131135.32.128.0/18135.32.128.1 to 135.32.191.254135.32.191.25516,382
132135.32.192.0/18135.32.192.1 to 135.32.255.254135.32.255.25516,382
133135.33.0.0/18135.33.0.1 to 135.33.63.254135.33.63.25516,382
134135.33.64.0/18135.33.64.1 to 135.33.127.254135.33.127.25516,382
135135.33.128.0/18135.33.128.1 to 135.33.191.254135.33.191.25516,382
136135.33.192.0/18135.33.192.1 to 135.33.255.254135.33.255.25516,382
137135.34.0.0/18135.34.0.1 to 135.34.63.254135.34.63.25516,382
138135.34.64.0/18135.34.64.1 to 135.34.127.254135.34.127.25516,382
139135.34.128.0/18135.34.128.1 to 135.34.191.254135.34.191.25516,382
140135.34.192.0/18135.34.192.1 to 135.34.255.254135.34.255.25516,382
141135.35.0.0/18135.35.0.1 to 135.35.63.254135.35.63.25516,382
142135.35.64.0/18135.35.64.1 to 135.35.127.254135.35.127.25516,382
143135.35.128.0/18135.35.128.1 to 135.35.191.254135.35.191.25516,382
144135.35.192.0/18135.35.192.1 to 135.35.255.254135.35.255.25516,382
145135.36.0.0/18135.36.0.1 to 135.36.63.254135.36.63.25516,382
146135.36.64.0/18135.36.64.1 to 135.36.127.254135.36.127.25516,382
147135.36.128.0/18135.36.128.1 to 135.36.191.254135.36.191.25516,382
148135.36.192.0/18135.36.192.1 to 135.36.255.254135.36.255.25516,382
149135.37.0.0/18135.37.0.1 to 135.37.63.254135.37.63.25516,382
150135.37.64.0/18135.37.64.1 to 135.37.127.254135.37.127.25516,382
151135.37.128.0/18135.37.128.1 to 135.37.191.254135.37.191.25516,382
152135.37.192.0/18135.37.192.1 to 135.37.255.254135.37.255.25516,382
153135.38.0.0/18135.38.0.1 to 135.38.63.254135.38.63.25516,382
154135.38.64.0/18135.38.64.1 to 135.38.127.254135.38.127.25516,382
155135.38.128.0/18135.38.128.1 to 135.38.191.254135.38.191.25516,382
156135.38.192.0/18135.38.192.1 to 135.38.255.254135.38.255.25516,382
157135.39.0.0/18135.39.0.1 to 135.39.63.254135.39.63.25516,382
158135.39.64.0/18135.39.64.1 to 135.39.127.254135.39.127.25516,382
159135.39.128.0/18135.39.128.1 to 135.39.191.254135.39.191.25516,382
160135.39.192.0/18135.39.192.1 to 135.39.255.254135.39.255.25516,382
161135.40.0.0/18135.40.0.1 to 135.40.63.254135.40.63.25516,382
162135.40.64.0/18135.40.64.1 to 135.40.127.254135.40.127.25516,382
163135.40.128.0/18135.40.128.1 to 135.40.191.254135.40.191.25516,382
164135.40.192.0/18135.40.192.1 to 135.40.255.254135.40.255.25516,382
165135.41.0.0/18135.41.0.1 to 135.41.63.254135.41.63.25516,382
166135.41.64.0/18135.41.64.1 to 135.41.127.254135.41.127.25516,382
167135.41.128.0/18135.41.128.1 to 135.41.191.254135.41.191.25516,382
168135.41.192.0/18135.41.192.1 to 135.41.255.254135.41.255.25516,382
169135.42.0.0/18135.42.0.1 to 135.42.63.254135.42.63.25516,382
170135.42.64.0/18135.42.64.1 to 135.42.127.254135.42.127.25516,382
171135.42.128.0/18135.42.128.1 to 135.42.191.254135.42.191.25516,382
172135.42.192.0/18135.42.192.1 to 135.42.255.254135.42.255.25516,382
173135.43.0.0/18135.43.0.1 to 135.43.63.254135.43.63.25516,382
174135.43.64.0/18135.43.64.1 to 135.43.127.254135.43.127.25516,382
175135.43.128.0/18135.43.128.1 to 135.43.191.254135.43.191.25516,382
176135.43.192.0/18135.43.192.1 to 135.43.255.254135.43.255.25516,382
177135.44.0.0/18135.44.0.1 to 135.44.63.254135.44.63.25516,382
178135.44.64.0/18135.44.64.1 to 135.44.127.254135.44.127.25516,382
179135.44.128.0/18135.44.128.1 to 135.44.191.254135.44.191.25516,382
180135.44.192.0/18135.44.192.1 to 135.44.255.254135.44.255.25516,382
181135.45.0.0/18135.45.0.1 to 135.45.63.254135.45.63.25516,382
182135.45.64.0/18135.45.64.1 to 135.45.127.254135.45.127.25516,382
183135.45.128.0/18135.45.128.1 to 135.45.191.254135.45.191.25516,382
184135.45.192.0/18135.45.192.1 to 135.45.255.254135.45.255.25516,382
185135.46.0.0/18135.46.0.1 to 135.46.63.254135.46.63.25516,382
186135.46.64.0/18135.46.64.1 to 135.46.127.254135.46.127.25516,382
187135.46.128.0/18135.46.128.1 to 135.46.191.254135.46.191.25516,382
188135.46.192.0/18135.46.192.1 to 135.46.255.254135.46.255.25516,382
189135.47.0.0/18135.47.0.1 to 135.47.63.254135.47.63.25516,382
190135.47.64.0/18135.47.64.1 to 135.47.127.254135.47.127.25516,382
191135.47.128.0/18135.47.128.1 to 135.47.191.254135.47.191.25516,382
192135.47.192.0/18135.47.192.1 to 135.47.255.254135.47.255.25516,382
193135.48.0.0/18135.48.0.1 to 135.48.63.254135.48.63.25516,382
194135.48.64.0/18135.48.64.1 to 135.48.127.254135.48.127.25516,382
195135.48.128.0/18135.48.128.1 to 135.48.191.254135.48.191.25516,382
196135.48.192.0/18135.48.192.1 to 135.48.255.254135.48.255.25516,382
197135.49.0.0/18135.49.0.1 to 135.49.63.254135.49.63.25516,382
198135.49.64.0/18135.49.64.1 to 135.49.127.254135.49.127.25516,382
199135.49.128.0/18135.49.128.1 to 135.49.191.254135.49.191.25516,382
200135.49.192.0/18135.49.192.1 to 135.49.255.254135.49.255.25516,382
201135.50.0.0/18135.50.0.1 to 135.50.63.254135.50.63.25516,382
202135.50.64.0/18135.50.64.1 to 135.50.127.254135.50.127.25516,382
203135.50.128.0/18135.50.128.1 to 135.50.191.254135.50.191.25516,382
204135.50.192.0/18135.50.192.1 to 135.50.255.254135.50.255.25516,382
205135.51.0.0/18135.51.0.1 to 135.51.63.254135.51.63.25516,382
206135.51.64.0/18135.51.64.1 to 135.51.127.254135.51.127.25516,382
207135.51.128.0/18135.51.128.1 to 135.51.191.254135.51.191.25516,382
208135.51.192.0/18135.51.192.1 to 135.51.255.254135.51.255.25516,382
209135.52.0.0/18135.52.0.1 to 135.52.63.254135.52.63.25516,382
210135.52.64.0/18135.52.64.1 to 135.52.127.254135.52.127.25516,382
211135.52.128.0/18135.52.128.1 to 135.52.191.254135.52.191.25516,382
212135.52.192.0/18135.52.192.1 to 135.52.255.254135.52.255.25516,382
213135.53.0.0/18135.53.0.1 to 135.53.63.254135.53.63.25516,382
214135.53.64.0/18135.53.64.1 to 135.53.127.254135.53.127.25516,382
215135.53.128.0/18135.53.128.1 to 135.53.191.254135.53.191.25516,382
216135.53.192.0/18135.53.192.1 to 135.53.255.254135.53.255.25516,382
217135.54.0.0/18135.54.0.1 to 135.54.63.254135.54.63.25516,382
218135.54.64.0/18135.54.64.1 to 135.54.127.254135.54.127.25516,382
219135.54.128.0/18135.54.128.1 to 135.54.191.254135.54.191.25516,382
220135.54.192.0/18135.54.192.1 to 135.54.255.254135.54.255.25516,382
221135.55.0.0/18135.55.0.1 to 135.55.63.254135.55.63.25516,382
222135.55.64.0/18135.55.64.1 to 135.55.127.254135.55.127.25516,382
223135.55.128.0/18135.55.128.1 to 135.55.191.254135.55.191.25516,382
224135.55.192.0/18135.55.192.1 to 135.55.255.254135.55.255.25516,382
225135.56.0.0/18135.56.0.1 to 135.56.63.254135.56.63.25516,382
226135.56.64.0/18135.56.64.1 to 135.56.127.254135.56.127.25516,382
227135.56.128.0/18135.56.128.1 to 135.56.191.254135.56.191.25516,382
228135.56.192.0/18135.56.192.1 to 135.56.255.254135.56.255.25516,382
229135.57.0.0/18135.57.0.1 to 135.57.63.254135.57.63.25516,382
230135.57.64.0/18135.57.64.1 to 135.57.127.254135.57.127.25516,382
231135.57.128.0/18135.57.128.1 to 135.57.191.254135.57.191.25516,382
232135.57.192.0/18135.57.192.1 to 135.57.255.254135.57.255.25516,382
233135.58.0.0/18135.58.0.1 to 135.58.63.254135.58.63.25516,382
234135.58.64.0/18135.58.64.1 to 135.58.127.254135.58.127.25516,382
235135.58.128.0/18135.58.128.1 to 135.58.191.254135.58.191.25516,382
236135.58.192.0/18135.58.192.1 to 135.58.255.254135.58.255.25516,382
237135.59.0.0/18135.59.0.1 to 135.59.63.254135.59.63.25516,382
238135.59.64.0/18135.59.64.1 to 135.59.127.254135.59.127.25516,382
239135.59.128.0/18135.59.128.1 to 135.59.191.254135.59.191.25516,382
240135.59.192.0/18135.59.192.1 to 135.59.255.254135.59.255.25516,382
241135.60.0.0/18135.60.0.1 to 135.60.63.254135.60.63.25516,382
242135.60.64.0/18135.60.64.1 to 135.60.127.254135.60.127.25516,382
243135.60.128.0/18135.60.128.1 to 135.60.191.254135.60.191.25516,382
244135.60.192.0/18135.60.192.1 to 135.60.255.254135.60.255.25516,382
245135.61.0.0/18135.61.0.1 to 135.61.63.254135.61.63.25516,382
246135.61.64.0/18135.61.64.1 to 135.61.127.254135.61.127.25516,382
247135.61.128.0/18135.61.128.1 to 135.61.191.254135.61.191.25516,382
248135.61.192.0/18135.61.192.1 to 135.61.255.254135.61.255.25516,382
249135.62.0.0/18135.62.0.1 to 135.62.63.254135.62.63.25516,382
250135.62.64.0/18135.62.64.1 to 135.62.127.254135.62.127.25516,382
251135.62.128.0/18135.62.128.1 to 135.62.191.254135.62.191.25516,382
252135.62.192.0/18135.62.192.1 to 135.62.255.254135.62.255.25516,382
253135.63.0.0/18135.63.0.1 to 135.63.63.254135.63.63.25516,382
254135.63.64.0/18135.63.64.1 to 135.63.127.254135.63.127.25516,382
255135.63.128.0/18135.63.128.1 to 135.63.191.254135.63.191.25516,382
256135.63.192.0/18135.63.192.1 to 135.63.255.254135.63.255.25516,382

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.