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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.

Network130.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
130.76.0.0
Broadcast address
130.79.255.255
First usable
130.76.0.1
Last usable
130.79.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
B (default /16)
As numbers
Hex 824C0000 · Integer 2186018816 to 2186280959
Reverse DNS zones
76.130.in-addr.arpa
77.130.in-addr.arpa
78.130.in-addr.arpa
79.130.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10000010.01001100.00000000.00000000130.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10000010.01001100.00000000.00000000130.76.0.0
Broadcast10000010.01001111.11111111.11111111130.79.255.255
Split into smaller subnets/25
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

130.76.0.0/14 makes 2,048 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1130.76.0.0/25130.76.0.1 to 130.76.0.126130.76.0.127126
2130.76.0.128/25130.76.0.129 to 130.76.0.254130.76.0.255126
3130.76.1.0/25130.76.1.1 to 130.76.1.126130.76.1.127126
4130.76.1.128/25130.76.1.129 to 130.76.1.254130.76.1.255126
5130.76.2.0/25130.76.2.1 to 130.76.2.126130.76.2.127126
6130.76.2.128/25130.76.2.129 to 130.76.2.254130.76.2.255126
7130.76.3.0/25130.76.3.1 to 130.76.3.126130.76.3.127126
8130.76.3.128/25130.76.3.129 to 130.76.3.254130.76.3.255126
9130.76.4.0/25130.76.4.1 to 130.76.4.126130.76.4.127126
10130.76.4.128/25130.76.4.129 to 130.76.4.254130.76.4.255126
11130.76.5.0/25130.76.5.1 to 130.76.5.126130.76.5.127126
12130.76.5.128/25130.76.5.129 to 130.76.5.254130.76.5.255126
13130.76.6.0/25130.76.6.1 to 130.76.6.126130.76.6.127126
14130.76.6.128/25130.76.6.129 to 130.76.6.254130.76.6.255126
15130.76.7.0/25130.76.7.1 to 130.76.7.126130.76.7.127126
16130.76.7.128/25130.76.7.129 to 130.76.7.254130.76.7.255126
17130.76.8.0/25130.76.8.1 to 130.76.8.126130.76.8.127126
18130.76.8.128/25130.76.8.129 to 130.76.8.254130.76.8.255126
19130.76.9.0/25130.76.9.1 to 130.76.9.126130.76.9.127126
20130.76.9.128/25130.76.9.129 to 130.76.9.254130.76.9.255126
21130.76.10.0/25130.76.10.1 to 130.76.10.126130.76.10.127126
22130.76.10.128/25130.76.10.129 to 130.76.10.254130.76.10.255126
23130.76.11.0/25130.76.11.1 to 130.76.11.126130.76.11.127126
24130.76.11.128/25130.76.11.129 to 130.76.11.254130.76.11.255126
25130.76.12.0/25130.76.12.1 to 130.76.12.126130.76.12.127126
26130.76.12.128/25130.76.12.129 to 130.76.12.254130.76.12.255126
27130.76.13.0/25130.76.13.1 to 130.76.13.126130.76.13.127126
28130.76.13.128/25130.76.13.129 to 130.76.13.254130.76.13.255126
29130.76.14.0/25130.76.14.1 to 130.76.14.126130.76.14.127126
30130.76.14.128/25130.76.14.129 to 130.76.14.254130.76.14.255126
31130.76.15.0/25130.76.15.1 to 130.76.15.126130.76.15.127126
32130.76.15.128/25130.76.15.129 to 130.76.15.254130.76.15.255126
33130.76.16.0/25130.76.16.1 to 130.76.16.126130.76.16.127126
34130.76.16.128/25130.76.16.129 to 130.76.16.254130.76.16.255126
35130.76.17.0/25130.76.17.1 to 130.76.17.126130.76.17.127126
36130.76.17.128/25130.76.17.129 to 130.76.17.254130.76.17.255126
37130.76.18.0/25130.76.18.1 to 130.76.18.126130.76.18.127126
38130.76.18.128/25130.76.18.129 to 130.76.18.254130.76.18.255126
39130.76.19.0/25130.76.19.1 to 130.76.19.126130.76.19.127126
40130.76.19.128/25130.76.19.129 to 130.76.19.254130.76.19.255126
41130.76.20.0/25130.76.20.1 to 130.76.20.126130.76.20.127126
42130.76.20.128/25130.76.20.129 to 130.76.20.254130.76.20.255126
43130.76.21.0/25130.76.21.1 to 130.76.21.126130.76.21.127126
44130.76.21.128/25130.76.21.129 to 130.76.21.254130.76.21.255126
45130.76.22.0/25130.76.22.1 to 130.76.22.126130.76.22.127126
46130.76.22.128/25130.76.22.129 to 130.76.22.254130.76.22.255126
47130.76.23.0/25130.76.23.1 to 130.76.23.126130.76.23.127126
48130.76.23.128/25130.76.23.129 to 130.76.23.254130.76.23.255126
49130.76.24.0/25130.76.24.1 to 130.76.24.126130.76.24.127126
50130.76.24.128/25130.76.24.129 to 130.76.24.254130.76.24.255126
51130.76.25.0/25130.76.25.1 to 130.76.25.126130.76.25.127126
52130.76.25.128/25130.76.25.129 to 130.76.25.254130.76.25.255126
53130.76.26.0/25130.76.26.1 to 130.76.26.126130.76.26.127126
54130.76.26.128/25130.76.26.129 to 130.76.26.254130.76.26.255126
55130.76.27.0/25130.76.27.1 to 130.76.27.126130.76.27.127126
56130.76.27.128/25130.76.27.129 to 130.76.27.254130.76.27.255126
57130.76.28.0/25130.76.28.1 to 130.76.28.126130.76.28.127126
58130.76.28.128/25130.76.28.129 to 130.76.28.254130.76.28.255126
59130.76.29.0/25130.76.29.1 to 130.76.29.126130.76.29.127126
60130.76.29.128/25130.76.29.129 to 130.76.29.254130.76.29.255126
61130.76.30.0/25130.76.30.1 to 130.76.30.126130.76.30.127126
62130.76.30.128/25130.76.30.129 to 130.76.30.254130.76.30.255126
63130.76.31.0/25130.76.31.1 to 130.76.31.126130.76.31.127126
64130.76.31.128/25130.76.31.129 to 130.76.31.254130.76.31.255126
65130.76.32.0/25130.76.32.1 to 130.76.32.126130.76.32.127126
66130.76.32.128/25130.76.32.129 to 130.76.32.254130.76.32.255126
67130.76.33.0/25130.76.33.1 to 130.76.33.126130.76.33.127126
68130.76.33.128/25130.76.33.129 to 130.76.33.254130.76.33.255126
69130.76.34.0/25130.76.34.1 to 130.76.34.126130.76.34.127126
70130.76.34.128/25130.76.34.129 to 130.76.34.254130.76.34.255126
71130.76.35.0/25130.76.35.1 to 130.76.35.126130.76.35.127126
72130.76.35.128/25130.76.35.129 to 130.76.35.254130.76.35.255126
73130.76.36.0/25130.76.36.1 to 130.76.36.126130.76.36.127126
74130.76.36.128/25130.76.36.129 to 130.76.36.254130.76.36.255126
75130.76.37.0/25130.76.37.1 to 130.76.37.126130.76.37.127126
76130.76.37.128/25130.76.37.129 to 130.76.37.254130.76.37.255126
77130.76.38.0/25130.76.38.1 to 130.76.38.126130.76.38.127126
78130.76.38.128/25130.76.38.129 to 130.76.38.254130.76.38.255126
79130.76.39.0/25130.76.39.1 to 130.76.39.126130.76.39.127126
80130.76.39.128/25130.76.39.129 to 130.76.39.254130.76.39.255126
81130.76.40.0/25130.76.40.1 to 130.76.40.126130.76.40.127126
82130.76.40.128/25130.76.40.129 to 130.76.40.254130.76.40.255126
83130.76.41.0/25130.76.41.1 to 130.76.41.126130.76.41.127126
84130.76.41.128/25130.76.41.129 to 130.76.41.254130.76.41.255126
85130.76.42.0/25130.76.42.1 to 130.76.42.126130.76.42.127126
86130.76.42.128/25130.76.42.129 to 130.76.42.254130.76.42.255126
87130.76.43.0/25130.76.43.1 to 130.76.43.126130.76.43.127126
88130.76.43.128/25130.76.43.129 to 130.76.43.254130.76.43.255126
89130.76.44.0/25130.76.44.1 to 130.76.44.126130.76.44.127126
90130.76.44.128/25130.76.44.129 to 130.76.44.254130.76.44.255126
91130.76.45.0/25130.76.45.1 to 130.76.45.126130.76.45.127126
92130.76.45.128/25130.76.45.129 to 130.76.45.254130.76.45.255126
93130.76.46.0/25130.76.46.1 to 130.76.46.126130.76.46.127126
94130.76.46.128/25130.76.46.129 to 130.76.46.254130.76.46.255126
95130.76.47.0/25130.76.47.1 to 130.76.47.126130.76.47.127126
96130.76.47.128/25130.76.47.129 to 130.76.47.254130.76.47.255126
97130.76.48.0/25130.76.48.1 to 130.76.48.126130.76.48.127126
98130.76.48.128/25130.76.48.129 to 130.76.48.254130.76.48.255126
99130.76.49.0/25130.76.49.1 to 130.76.49.126130.76.49.127126
100130.76.49.128/25130.76.49.129 to 130.76.49.254130.76.49.255126
101130.76.50.0/25130.76.50.1 to 130.76.50.126130.76.50.127126
102130.76.50.128/25130.76.50.129 to 130.76.50.254130.76.50.255126
103130.76.51.0/25130.76.51.1 to 130.76.51.126130.76.51.127126
104130.76.51.128/25130.76.51.129 to 130.76.51.254130.76.51.255126
105130.76.52.0/25130.76.52.1 to 130.76.52.126130.76.52.127126
106130.76.52.128/25130.76.52.129 to 130.76.52.254130.76.52.255126
107130.76.53.0/25130.76.53.1 to 130.76.53.126130.76.53.127126
108130.76.53.128/25130.76.53.129 to 130.76.53.254130.76.53.255126
109130.76.54.0/25130.76.54.1 to 130.76.54.126130.76.54.127126
110130.76.54.128/25130.76.54.129 to 130.76.54.254130.76.54.255126
111130.76.55.0/25130.76.55.1 to 130.76.55.126130.76.55.127126
112130.76.55.128/25130.76.55.129 to 130.76.55.254130.76.55.255126
113130.76.56.0/25130.76.56.1 to 130.76.56.126130.76.56.127126
114130.76.56.128/25130.76.56.129 to 130.76.56.254130.76.56.255126
115130.76.57.0/25130.76.57.1 to 130.76.57.126130.76.57.127126
116130.76.57.128/25130.76.57.129 to 130.76.57.254130.76.57.255126
117130.76.58.0/25130.76.58.1 to 130.76.58.126130.76.58.127126
118130.76.58.128/25130.76.58.129 to 130.76.58.254130.76.58.255126
119130.76.59.0/25130.76.59.1 to 130.76.59.126130.76.59.127126
120130.76.59.128/25130.76.59.129 to 130.76.59.254130.76.59.255126
121130.76.60.0/25130.76.60.1 to 130.76.60.126130.76.60.127126
122130.76.60.128/25130.76.60.129 to 130.76.60.254130.76.60.255126
123130.76.61.0/25130.76.61.1 to 130.76.61.126130.76.61.127126
124130.76.61.128/25130.76.61.129 to 130.76.61.254130.76.61.255126
125130.76.62.0/25130.76.62.1 to 130.76.62.126130.76.62.127126
126130.76.62.128/25130.76.62.129 to 130.76.62.254130.76.62.255126
127130.76.63.0/25130.76.63.1 to 130.76.63.126130.76.63.127126
128130.76.63.128/25130.76.63.129 to 130.76.63.254130.76.63.255126
129130.76.64.0/25130.76.64.1 to 130.76.64.126130.76.64.127126
130130.76.64.128/25130.76.64.129 to 130.76.64.254130.76.64.255126
131130.76.65.0/25130.76.65.1 to 130.76.65.126130.76.65.127126
132130.76.65.128/25130.76.65.129 to 130.76.65.254130.76.65.255126
133130.76.66.0/25130.76.66.1 to 130.76.66.126130.76.66.127126
134130.76.66.128/25130.76.66.129 to 130.76.66.254130.76.66.255126
135130.76.67.0/25130.76.67.1 to 130.76.67.126130.76.67.127126
136130.76.67.128/25130.76.67.129 to 130.76.67.254130.76.67.255126
137130.76.68.0/25130.76.68.1 to 130.76.68.126130.76.68.127126
138130.76.68.128/25130.76.68.129 to 130.76.68.254130.76.68.255126
139130.76.69.0/25130.76.69.1 to 130.76.69.126130.76.69.127126
140130.76.69.128/25130.76.69.129 to 130.76.69.254130.76.69.255126
141130.76.70.0/25130.76.70.1 to 130.76.70.126130.76.70.127126
142130.76.70.128/25130.76.70.129 to 130.76.70.254130.76.70.255126
143130.76.71.0/25130.76.71.1 to 130.76.71.126130.76.71.127126
144130.76.71.128/25130.76.71.129 to 130.76.71.254130.76.71.255126
145130.76.72.0/25130.76.72.1 to 130.76.72.126130.76.72.127126
146130.76.72.128/25130.76.72.129 to 130.76.72.254130.76.72.255126
147130.76.73.0/25130.76.73.1 to 130.76.73.126130.76.73.127126
148130.76.73.128/25130.76.73.129 to 130.76.73.254130.76.73.255126
149130.76.74.0/25130.76.74.1 to 130.76.74.126130.76.74.127126
150130.76.74.128/25130.76.74.129 to 130.76.74.254130.76.74.255126
151130.76.75.0/25130.76.75.1 to 130.76.75.126130.76.75.127126
152130.76.75.128/25130.76.75.129 to 130.76.75.254130.76.75.255126
153130.76.76.0/25130.76.76.1 to 130.76.76.126130.76.76.127126
154130.76.76.128/25130.76.76.129 to 130.76.76.254130.76.76.255126
155130.76.77.0/25130.76.77.1 to 130.76.77.126130.76.77.127126
156130.76.77.128/25130.76.77.129 to 130.76.77.254130.76.77.255126
157130.76.78.0/25130.76.78.1 to 130.76.78.126130.76.78.127126
158130.76.78.128/25130.76.78.129 to 130.76.78.254130.76.78.255126
159130.76.79.0/25130.76.79.1 to 130.76.79.126130.76.79.127126
160130.76.79.128/25130.76.79.129 to 130.76.79.254130.76.79.255126
161130.76.80.0/25130.76.80.1 to 130.76.80.126130.76.80.127126
162130.76.80.128/25130.76.80.129 to 130.76.80.254130.76.80.255126
163130.76.81.0/25130.76.81.1 to 130.76.81.126130.76.81.127126
164130.76.81.128/25130.76.81.129 to 130.76.81.254130.76.81.255126
165130.76.82.0/25130.76.82.1 to 130.76.82.126130.76.82.127126
166130.76.82.128/25130.76.82.129 to 130.76.82.254130.76.82.255126
167130.76.83.0/25130.76.83.1 to 130.76.83.126130.76.83.127126
168130.76.83.128/25130.76.83.129 to 130.76.83.254130.76.83.255126
169130.76.84.0/25130.76.84.1 to 130.76.84.126130.76.84.127126
170130.76.84.128/25130.76.84.129 to 130.76.84.254130.76.84.255126
171130.76.85.0/25130.76.85.1 to 130.76.85.126130.76.85.127126
172130.76.85.128/25130.76.85.129 to 130.76.85.254130.76.85.255126
173130.76.86.0/25130.76.86.1 to 130.76.86.126130.76.86.127126
174130.76.86.128/25130.76.86.129 to 130.76.86.254130.76.86.255126
175130.76.87.0/25130.76.87.1 to 130.76.87.126130.76.87.127126
176130.76.87.128/25130.76.87.129 to 130.76.87.254130.76.87.255126
177130.76.88.0/25130.76.88.1 to 130.76.88.126130.76.88.127126
178130.76.88.128/25130.76.88.129 to 130.76.88.254130.76.88.255126
179130.76.89.0/25130.76.89.1 to 130.76.89.126130.76.89.127126
180130.76.89.128/25130.76.89.129 to 130.76.89.254130.76.89.255126
181130.76.90.0/25130.76.90.1 to 130.76.90.126130.76.90.127126
182130.76.90.128/25130.76.90.129 to 130.76.90.254130.76.90.255126
183130.76.91.0/25130.76.91.1 to 130.76.91.126130.76.91.127126
184130.76.91.128/25130.76.91.129 to 130.76.91.254130.76.91.255126
185130.76.92.0/25130.76.92.1 to 130.76.92.126130.76.92.127126
186130.76.92.128/25130.76.92.129 to 130.76.92.254130.76.92.255126
187130.76.93.0/25130.76.93.1 to 130.76.93.126130.76.93.127126
188130.76.93.128/25130.76.93.129 to 130.76.93.254130.76.93.255126
189130.76.94.0/25130.76.94.1 to 130.76.94.126130.76.94.127126
190130.76.94.128/25130.76.94.129 to 130.76.94.254130.76.94.255126
191130.76.95.0/25130.76.95.1 to 130.76.95.126130.76.95.127126
192130.76.95.128/25130.76.95.129 to 130.76.95.254130.76.95.255126
193130.76.96.0/25130.76.96.1 to 130.76.96.126130.76.96.127126
194130.76.96.128/25130.76.96.129 to 130.76.96.254130.76.96.255126
195130.76.97.0/25130.76.97.1 to 130.76.97.126130.76.97.127126
196130.76.97.128/25130.76.97.129 to 130.76.97.254130.76.97.255126
197130.76.98.0/25130.76.98.1 to 130.76.98.126130.76.98.127126
198130.76.98.128/25130.76.98.129 to 130.76.98.254130.76.98.255126
199130.76.99.0/25130.76.99.1 to 130.76.99.126130.76.99.127126
200130.76.99.128/25130.76.99.129 to 130.76.99.254130.76.99.255126
201130.76.100.0/25130.76.100.1 to 130.76.100.126130.76.100.127126
202130.76.100.128/25130.76.100.129 to 130.76.100.254130.76.100.255126
203130.76.101.0/25130.76.101.1 to 130.76.101.126130.76.101.127126
204130.76.101.128/25130.76.101.129 to 130.76.101.254130.76.101.255126
205130.76.102.0/25130.76.102.1 to 130.76.102.126130.76.102.127126
206130.76.102.128/25130.76.102.129 to 130.76.102.254130.76.102.255126
207130.76.103.0/25130.76.103.1 to 130.76.103.126130.76.103.127126
208130.76.103.128/25130.76.103.129 to 130.76.103.254130.76.103.255126
209130.76.104.0/25130.76.104.1 to 130.76.104.126130.76.104.127126
210130.76.104.128/25130.76.104.129 to 130.76.104.254130.76.104.255126
211130.76.105.0/25130.76.105.1 to 130.76.105.126130.76.105.127126
212130.76.105.128/25130.76.105.129 to 130.76.105.254130.76.105.255126
213130.76.106.0/25130.76.106.1 to 130.76.106.126130.76.106.127126
214130.76.106.128/25130.76.106.129 to 130.76.106.254130.76.106.255126
215130.76.107.0/25130.76.107.1 to 130.76.107.126130.76.107.127126
216130.76.107.128/25130.76.107.129 to 130.76.107.254130.76.107.255126
217130.76.108.0/25130.76.108.1 to 130.76.108.126130.76.108.127126
218130.76.108.128/25130.76.108.129 to 130.76.108.254130.76.108.255126
219130.76.109.0/25130.76.109.1 to 130.76.109.126130.76.109.127126
220130.76.109.128/25130.76.109.129 to 130.76.109.254130.76.109.255126
221130.76.110.0/25130.76.110.1 to 130.76.110.126130.76.110.127126
222130.76.110.128/25130.76.110.129 to 130.76.110.254130.76.110.255126
223130.76.111.0/25130.76.111.1 to 130.76.111.126130.76.111.127126
224130.76.111.128/25130.76.111.129 to 130.76.111.254130.76.111.255126
225130.76.112.0/25130.76.112.1 to 130.76.112.126130.76.112.127126
226130.76.112.128/25130.76.112.129 to 130.76.112.254130.76.112.255126
227130.76.113.0/25130.76.113.1 to 130.76.113.126130.76.113.127126
228130.76.113.128/25130.76.113.129 to 130.76.113.254130.76.113.255126
229130.76.114.0/25130.76.114.1 to 130.76.114.126130.76.114.127126
230130.76.114.128/25130.76.114.129 to 130.76.114.254130.76.114.255126
231130.76.115.0/25130.76.115.1 to 130.76.115.126130.76.115.127126
232130.76.115.128/25130.76.115.129 to 130.76.115.254130.76.115.255126
233130.76.116.0/25130.76.116.1 to 130.76.116.126130.76.116.127126
234130.76.116.128/25130.76.116.129 to 130.76.116.254130.76.116.255126
235130.76.117.0/25130.76.117.1 to 130.76.117.126130.76.117.127126
236130.76.117.128/25130.76.117.129 to 130.76.117.254130.76.117.255126
237130.76.118.0/25130.76.118.1 to 130.76.118.126130.76.118.127126
238130.76.118.128/25130.76.118.129 to 130.76.118.254130.76.118.255126
239130.76.119.0/25130.76.119.1 to 130.76.119.126130.76.119.127126
240130.76.119.128/25130.76.119.129 to 130.76.119.254130.76.119.255126
241130.76.120.0/25130.76.120.1 to 130.76.120.126130.76.120.127126
242130.76.120.128/25130.76.120.129 to 130.76.120.254130.76.120.255126
243130.76.121.0/25130.76.121.1 to 130.76.121.126130.76.121.127126
244130.76.121.128/25130.76.121.129 to 130.76.121.254130.76.121.255126
245130.76.122.0/25130.76.122.1 to 130.76.122.126130.76.122.127126
246130.76.122.128/25130.76.122.129 to 130.76.122.254130.76.122.255126
247130.76.123.0/25130.76.123.1 to 130.76.123.126130.76.123.127126
248130.76.123.128/25130.76.123.129 to 130.76.123.254130.76.123.255126
249130.76.124.0/25130.76.124.1 to 130.76.124.126130.76.124.127126
250130.76.124.128/25130.76.124.129 to 130.76.124.254130.76.124.255126
251130.76.125.0/25130.76.125.1 to 130.76.125.126130.76.125.127126
252130.76.125.128/25130.76.125.129 to 130.76.125.254130.76.125.255126
253130.76.126.0/25130.76.126.1 to 130.76.126.126130.76.126.127126
254130.76.126.128/25130.76.126.129 to 130.76.126.254130.76.126.255126
255130.76.127.0/25130.76.127.1 to 130.76.127.126130.76.127.127126
256130.76.127.128/25130.76.127.129 to 130.76.127.254130.76.127.255126

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.