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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.

Network228.152.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
228.152.0.0
Broadcast address
228.159.255.255
First usable
228.152.0.1
Last usable
228.159.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E4980000 · Integer 3835166720 to 3835691007
Reverse DNS zones
152.228.in-addr.arpa
153.228.in-addr.arpa
154.228.in-addr.arpa
155.228.in-addr.arpa
156.228.in-addr.arpa
157.228.in-addr.arpa
158.228.in-addr.arpa
159.228.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100100.10011000.00000000.00000000228.152.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network11100100.10011000.00000000.00000000228.152.0.0
Broadcast11100100.10011111.11111111.11111111228.159.255.255
Split into smaller subnets/25
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

228.152.0.0/13 makes 4,096 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1228.152.0.0/25228.152.0.1 to 228.152.0.126228.152.0.127126
2228.152.0.128/25228.152.0.129 to 228.152.0.254228.152.0.255126
3228.152.1.0/25228.152.1.1 to 228.152.1.126228.152.1.127126
4228.152.1.128/25228.152.1.129 to 228.152.1.254228.152.1.255126
5228.152.2.0/25228.152.2.1 to 228.152.2.126228.152.2.127126
6228.152.2.128/25228.152.2.129 to 228.152.2.254228.152.2.255126
7228.152.3.0/25228.152.3.1 to 228.152.3.126228.152.3.127126
8228.152.3.128/25228.152.3.129 to 228.152.3.254228.152.3.255126
9228.152.4.0/25228.152.4.1 to 228.152.4.126228.152.4.127126
10228.152.4.128/25228.152.4.129 to 228.152.4.254228.152.4.255126
11228.152.5.0/25228.152.5.1 to 228.152.5.126228.152.5.127126
12228.152.5.128/25228.152.5.129 to 228.152.5.254228.152.5.255126
13228.152.6.0/25228.152.6.1 to 228.152.6.126228.152.6.127126
14228.152.6.128/25228.152.6.129 to 228.152.6.254228.152.6.255126
15228.152.7.0/25228.152.7.1 to 228.152.7.126228.152.7.127126
16228.152.7.128/25228.152.7.129 to 228.152.7.254228.152.7.255126
17228.152.8.0/25228.152.8.1 to 228.152.8.126228.152.8.127126
18228.152.8.128/25228.152.8.129 to 228.152.8.254228.152.8.255126
19228.152.9.0/25228.152.9.1 to 228.152.9.126228.152.9.127126
20228.152.9.128/25228.152.9.129 to 228.152.9.254228.152.9.255126
21228.152.10.0/25228.152.10.1 to 228.152.10.126228.152.10.127126
22228.152.10.128/25228.152.10.129 to 228.152.10.254228.152.10.255126
23228.152.11.0/25228.152.11.1 to 228.152.11.126228.152.11.127126
24228.152.11.128/25228.152.11.129 to 228.152.11.254228.152.11.255126
25228.152.12.0/25228.152.12.1 to 228.152.12.126228.152.12.127126
26228.152.12.128/25228.152.12.129 to 228.152.12.254228.152.12.255126
27228.152.13.0/25228.152.13.1 to 228.152.13.126228.152.13.127126
28228.152.13.128/25228.152.13.129 to 228.152.13.254228.152.13.255126
29228.152.14.0/25228.152.14.1 to 228.152.14.126228.152.14.127126
30228.152.14.128/25228.152.14.129 to 228.152.14.254228.152.14.255126
31228.152.15.0/25228.152.15.1 to 228.152.15.126228.152.15.127126
32228.152.15.128/25228.152.15.129 to 228.152.15.254228.152.15.255126
33228.152.16.0/25228.152.16.1 to 228.152.16.126228.152.16.127126
34228.152.16.128/25228.152.16.129 to 228.152.16.254228.152.16.255126
35228.152.17.0/25228.152.17.1 to 228.152.17.126228.152.17.127126
36228.152.17.128/25228.152.17.129 to 228.152.17.254228.152.17.255126
37228.152.18.0/25228.152.18.1 to 228.152.18.126228.152.18.127126
38228.152.18.128/25228.152.18.129 to 228.152.18.254228.152.18.255126
39228.152.19.0/25228.152.19.1 to 228.152.19.126228.152.19.127126
40228.152.19.128/25228.152.19.129 to 228.152.19.254228.152.19.255126
41228.152.20.0/25228.152.20.1 to 228.152.20.126228.152.20.127126
42228.152.20.128/25228.152.20.129 to 228.152.20.254228.152.20.255126
43228.152.21.0/25228.152.21.1 to 228.152.21.126228.152.21.127126
44228.152.21.128/25228.152.21.129 to 228.152.21.254228.152.21.255126
45228.152.22.0/25228.152.22.1 to 228.152.22.126228.152.22.127126
46228.152.22.128/25228.152.22.129 to 228.152.22.254228.152.22.255126
47228.152.23.0/25228.152.23.1 to 228.152.23.126228.152.23.127126
48228.152.23.128/25228.152.23.129 to 228.152.23.254228.152.23.255126
49228.152.24.0/25228.152.24.1 to 228.152.24.126228.152.24.127126
50228.152.24.128/25228.152.24.129 to 228.152.24.254228.152.24.255126
51228.152.25.0/25228.152.25.1 to 228.152.25.126228.152.25.127126
52228.152.25.128/25228.152.25.129 to 228.152.25.254228.152.25.255126
53228.152.26.0/25228.152.26.1 to 228.152.26.126228.152.26.127126
54228.152.26.128/25228.152.26.129 to 228.152.26.254228.152.26.255126
55228.152.27.0/25228.152.27.1 to 228.152.27.126228.152.27.127126
56228.152.27.128/25228.152.27.129 to 228.152.27.254228.152.27.255126
57228.152.28.0/25228.152.28.1 to 228.152.28.126228.152.28.127126
58228.152.28.128/25228.152.28.129 to 228.152.28.254228.152.28.255126
59228.152.29.0/25228.152.29.1 to 228.152.29.126228.152.29.127126
60228.152.29.128/25228.152.29.129 to 228.152.29.254228.152.29.255126
61228.152.30.0/25228.152.30.1 to 228.152.30.126228.152.30.127126
62228.152.30.128/25228.152.30.129 to 228.152.30.254228.152.30.255126
63228.152.31.0/25228.152.31.1 to 228.152.31.126228.152.31.127126
64228.152.31.128/25228.152.31.129 to 228.152.31.254228.152.31.255126
65228.152.32.0/25228.152.32.1 to 228.152.32.126228.152.32.127126
66228.152.32.128/25228.152.32.129 to 228.152.32.254228.152.32.255126
67228.152.33.0/25228.152.33.1 to 228.152.33.126228.152.33.127126
68228.152.33.128/25228.152.33.129 to 228.152.33.254228.152.33.255126
69228.152.34.0/25228.152.34.1 to 228.152.34.126228.152.34.127126
70228.152.34.128/25228.152.34.129 to 228.152.34.254228.152.34.255126
71228.152.35.0/25228.152.35.1 to 228.152.35.126228.152.35.127126
72228.152.35.128/25228.152.35.129 to 228.152.35.254228.152.35.255126
73228.152.36.0/25228.152.36.1 to 228.152.36.126228.152.36.127126
74228.152.36.128/25228.152.36.129 to 228.152.36.254228.152.36.255126
75228.152.37.0/25228.152.37.1 to 228.152.37.126228.152.37.127126
76228.152.37.128/25228.152.37.129 to 228.152.37.254228.152.37.255126
77228.152.38.0/25228.152.38.1 to 228.152.38.126228.152.38.127126
78228.152.38.128/25228.152.38.129 to 228.152.38.254228.152.38.255126
79228.152.39.0/25228.152.39.1 to 228.152.39.126228.152.39.127126
80228.152.39.128/25228.152.39.129 to 228.152.39.254228.152.39.255126
81228.152.40.0/25228.152.40.1 to 228.152.40.126228.152.40.127126
82228.152.40.128/25228.152.40.129 to 228.152.40.254228.152.40.255126
83228.152.41.0/25228.152.41.1 to 228.152.41.126228.152.41.127126
84228.152.41.128/25228.152.41.129 to 228.152.41.254228.152.41.255126
85228.152.42.0/25228.152.42.1 to 228.152.42.126228.152.42.127126
86228.152.42.128/25228.152.42.129 to 228.152.42.254228.152.42.255126
87228.152.43.0/25228.152.43.1 to 228.152.43.126228.152.43.127126
88228.152.43.128/25228.152.43.129 to 228.152.43.254228.152.43.255126
89228.152.44.0/25228.152.44.1 to 228.152.44.126228.152.44.127126
90228.152.44.128/25228.152.44.129 to 228.152.44.254228.152.44.255126
91228.152.45.0/25228.152.45.1 to 228.152.45.126228.152.45.127126
92228.152.45.128/25228.152.45.129 to 228.152.45.254228.152.45.255126
93228.152.46.0/25228.152.46.1 to 228.152.46.126228.152.46.127126
94228.152.46.128/25228.152.46.129 to 228.152.46.254228.152.46.255126
95228.152.47.0/25228.152.47.1 to 228.152.47.126228.152.47.127126
96228.152.47.128/25228.152.47.129 to 228.152.47.254228.152.47.255126
97228.152.48.0/25228.152.48.1 to 228.152.48.126228.152.48.127126
98228.152.48.128/25228.152.48.129 to 228.152.48.254228.152.48.255126
99228.152.49.0/25228.152.49.1 to 228.152.49.126228.152.49.127126
100228.152.49.128/25228.152.49.129 to 228.152.49.254228.152.49.255126
101228.152.50.0/25228.152.50.1 to 228.152.50.126228.152.50.127126
102228.152.50.128/25228.152.50.129 to 228.152.50.254228.152.50.255126
103228.152.51.0/25228.152.51.1 to 228.152.51.126228.152.51.127126
104228.152.51.128/25228.152.51.129 to 228.152.51.254228.152.51.255126
105228.152.52.0/25228.152.52.1 to 228.152.52.126228.152.52.127126
106228.152.52.128/25228.152.52.129 to 228.152.52.254228.152.52.255126
107228.152.53.0/25228.152.53.1 to 228.152.53.126228.152.53.127126
108228.152.53.128/25228.152.53.129 to 228.152.53.254228.152.53.255126
109228.152.54.0/25228.152.54.1 to 228.152.54.126228.152.54.127126
110228.152.54.128/25228.152.54.129 to 228.152.54.254228.152.54.255126
111228.152.55.0/25228.152.55.1 to 228.152.55.126228.152.55.127126
112228.152.55.128/25228.152.55.129 to 228.152.55.254228.152.55.255126
113228.152.56.0/25228.152.56.1 to 228.152.56.126228.152.56.127126
114228.152.56.128/25228.152.56.129 to 228.152.56.254228.152.56.255126
115228.152.57.0/25228.152.57.1 to 228.152.57.126228.152.57.127126
116228.152.57.128/25228.152.57.129 to 228.152.57.254228.152.57.255126
117228.152.58.0/25228.152.58.1 to 228.152.58.126228.152.58.127126
118228.152.58.128/25228.152.58.129 to 228.152.58.254228.152.58.255126
119228.152.59.0/25228.152.59.1 to 228.152.59.126228.152.59.127126
120228.152.59.128/25228.152.59.129 to 228.152.59.254228.152.59.255126
121228.152.60.0/25228.152.60.1 to 228.152.60.126228.152.60.127126
122228.152.60.128/25228.152.60.129 to 228.152.60.254228.152.60.255126
123228.152.61.0/25228.152.61.1 to 228.152.61.126228.152.61.127126
124228.152.61.128/25228.152.61.129 to 228.152.61.254228.152.61.255126
125228.152.62.0/25228.152.62.1 to 228.152.62.126228.152.62.127126
126228.152.62.128/25228.152.62.129 to 228.152.62.254228.152.62.255126
127228.152.63.0/25228.152.63.1 to 228.152.63.126228.152.63.127126
128228.152.63.128/25228.152.63.129 to 228.152.63.254228.152.63.255126
129228.152.64.0/25228.152.64.1 to 228.152.64.126228.152.64.127126
130228.152.64.128/25228.152.64.129 to 228.152.64.254228.152.64.255126
131228.152.65.0/25228.152.65.1 to 228.152.65.126228.152.65.127126
132228.152.65.128/25228.152.65.129 to 228.152.65.254228.152.65.255126
133228.152.66.0/25228.152.66.1 to 228.152.66.126228.152.66.127126
134228.152.66.128/25228.152.66.129 to 228.152.66.254228.152.66.255126
135228.152.67.0/25228.152.67.1 to 228.152.67.126228.152.67.127126
136228.152.67.128/25228.152.67.129 to 228.152.67.254228.152.67.255126
137228.152.68.0/25228.152.68.1 to 228.152.68.126228.152.68.127126
138228.152.68.128/25228.152.68.129 to 228.152.68.254228.152.68.255126
139228.152.69.0/25228.152.69.1 to 228.152.69.126228.152.69.127126
140228.152.69.128/25228.152.69.129 to 228.152.69.254228.152.69.255126
141228.152.70.0/25228.152.70.1 to 228.152.70.126228.152.70.127126
142228.152.70.128/25228.152.70.129 to 228.152.70.254228.152.70.255126
143228.152.71.0/25228.152.71.1 to 228.152.71.126228.152.71.127126
144228.152.71.128/25228.152.71.129 to 228.152.71.254228.152.71.255126
145228.152.72.0/25228.152.72.1 to 228.152.72.126228.152.72.127126
146228.152.72.128/25228.152.72.129 to 228.152.72.254228.152.72.255126
147228.152.73.0/25228.152.73.1 to 228.152.73.126228.152.73.127126
148228.152.73.128/25228.152.73.129 to 228.152.73.254228.152.73.255126
149228.152.74.0/25228.152.74.1 to 228.152.74.126228.152.74.127126
150228.152.74.128/25228.152.74.129 to 228.152.74.254228.152.74.255126
151228.152.75.0/25228.152.75.1 to 228.152.75.126228.152.75.127126
152228.152.75.128/25228.152.75.129 to 228.152.75.254228.152.75.255126
153228.152.76.0/25228.152.76.1 to 228.152.76.126228.152.76.127126
154228.152.76.128/25228.152.76.129 to 228.152.76.254228.152.76.255126
155228.152.77.0/25228.152.77.1 to 228.152.77.126228.152.77.127126
156228.152.77.128/25228.152.77.129 to 228.152.77.254228.152.77.255126
157228.152.78.0/25228.152.78.1 to 228.152.78.126228.152.78.127126
158228.152.78.128/25228.152.78.129 to 228.152.78.254228.152.78.255126
159228.152.79.0/25228.152.79.1 to 228.152.79.126228.152.79.127126
160228.152.79.128/25228.152.79.129 to 228.152.79.254228.152.79.255126
161228.152.80.0/25228.152.80.1 to 228.152.80.126228.152.80.127126
162228.152.80.128/25228.152.80.129 to 228.152.80.254228.152.80.255126
163228.152.81.0/25228.152.81.1 to 228.152.81.126228.152.81.127126
164228.152.81.128/25228.152.81.129 to 228.152.81.254228.152.81.255126
165228.152.82.0/25228.152.82.1 to 228.152.82.126228.152.82.127126
166228.152.82.128/25228.152.82.129 to 228.152.82.254228.152.82.255126
167228.152.83.0/25228.152.83.1 to 228.152.83.126228.152.83.127126
168228.152.83.128/25228.152.83.129 to 228.152.83.254228.152.83.255126
169228.152.84.0/25228.152.84.1 to 228.152.84.126228.152.84.127126
170228.152.84.128/25228.152.84.129 to 228.152.84.254228.152.84.255126
171228.152.85.0/25228.152.85.1 to 228.152.85.126228.152.85.127126
172228.152.85.128/25228.152.85.129 to 228.152.85.254228.152.85.255126
173228.152.86.0/25228.152.86.1 to 228.152.86.126228.152.86.127126
174228.152.86.128/25228.152.86.129 to 228.152.86.254228.152.86.255126
175228.152.87.0/25228.152.87.1 to 228.152.87.126228.152.87.127126
176228.152.87.128/25228.152.87.129 to 228.152.87.254228.152.87.255126
177228.152.88.0/25228.152.88.1 to 228.152.88.126228.152.88.127126
178228.152.88.128/25228.152.88.129 to 228.152.88.254228.152.88.255126
179228.152.89.0/25228.152.89.1 to 228.152.89.126228.152.89.127126
180228.152.89.128/25228.152.89.129 to 228.152.89.254228.152.89.255126
181228.152.90.0/25228.152.90.1 to 228.152.90.126228.152.90.127126
182228.152.90.128/25228.152.90.129 to 228.152.90.254228.152.90.255126
183228.152.91.0/25228.152.91.1 to 228.152.91.126228.152.91.127126
184228.152.91.128/25228.152.91.129 to 228.152.91.254228.152.91.255126
185228.152.92.0/25228.152.92.1 to 228.152.92.126228.152.92.127126
186228.152.92.128/25228.152.92.129 to 228.152.92.254228.152.92.255126
187228.152.93.0/25228.152.93.1 to 228.152.93.126228.152.93.127126
188228.152.93.128/25228.152.93.129 to 228.152.93.254228.152.93.255126
189228.152.94.0/25228.152.94.1 to 228.152.94.126228.152.94.127126
190228.152.94.128/25228.152.94.129 to 228.152.94.254228.152.94.255126
191228.152.95.0/25228.152.95.1 to 228.152.95.126228.152.95.127126
192228.152.95.128/25228.152.95.129 to 228.152.95.254228.152.95.255126
193228.152.96.0/25228.152.96.1 to 228.152.96.126228.152.96.127126
194228.152.96.128/25228.152.96.129 to 228.152.96.254228.152.96.255126
195228.152.97.0/25228.152.97.1 to 228.152.97.126228.152.97.127126
196228.152.97.128/25228.152.97.129 to 228.152.97.254228.152.97.255126
197228.152.98.0/25228.152.98.1 to 228.152.98.126228.152.98.127126
198228.152.98.128/25228.152.98.129 to 228.152.98.254228.152.98.255126
199228.152.99.0/25228.152.99.1 to 228.152.99.126228.152.99.127126
200228.152.99.128/25228.152.99.129 to 228.152.99.254228.152.99.255126
201228.152.100.0/25228.152.100.1 to 228.152.100.126228.152.100.127126
202228.152.100.128/25228.152.100.129 to 228.152.100.254228.152.100.255126
203228.152.101.0/25228.152.101.1 to 228.152.101.126228.152.101.127126
204228.152.101.128/25228.152.101.129 to 228.152.101.254228.152.101.255126
205228.152.102.0/25228.152.102.1 to 228.152.102.126228.152.102.127126
206228.152.102.128/25228.152.102.129 to 228.152.102.254228.152.102.255126
207228.152.103.0/25228.152.103.1 to 228.152.103.126228.152.103.127126
208228.152.103.128/25228.152.103.129 to 228.152.103.254228.152.103.255126
209228.152.104.0/25228.152.104.1 to 228.152.104.126228.152.104.127126
210228.152.104.128/25228.152.104.129 to 228.152.104.254228.152.104.255126
211228.152.105.0/25228.152.105.1 to 228.152.105.126228.152.105.127126
212228.152.105.128/25228.152.105.129 to 228.152.105.254228.152.105.255126
213228.152.106.0/25228.152.106.1 to 228.152.106.126228.152.106.127126
214228.152.106.128/25228.152.106.129 to 228.152.106.254228.152.106.255126
215228.152.107.0/25228.152.107.1 to 228.152.107.126228.152.107.127126
216228.152.107.128/25228.152.107.129 to 228.152.107.254228.152.107.255126
217228.152.108.0/25228.152.108.1 to 228.152.108.126228.152.108.127126
218228.152.108.128/25228.152.108.129 to 228.152.108.254228.152.108.255126
219228.152.109.0/25228.152.109.1 to 228.152.109.126228.152.109.127126
220228.152.109.128/25228.152.109.129 to 228.152.109.254228.152.109.255126
221228.152.110.0/25228.152.110.1 to 228.152.110.126228.152.110.127126
222228.152.110.128/25228.152.110.129 to 228.152.110.254228.152.110.255126
223228.152.111.0/25228.152.111.1 to 228.152.111.126228.152.111.127126
224228.152.111.128/25228.152.111.129 to 228.152.111.254228.152.111.255126
225228.152.112.0/25228.152.112.1 to 228.152.112.126228.152.112.127126
226228.152.112.128/25228.152.112.129 to 228.152.112.254228.152.112.255126
227228.152.113.0/25228.152.113.1 to 228.152.113.126228.152.113.127126
228228.152.113.128/25228.152.113.129 to 228.152.113.254228.152.113.255126
229228.152.114.0/25228.152.114.1 to 228.152.114.126228.152.114.127126
230228.152.114.128/25228.152.114.129 to 228.152.114.254228.152.114.255126
231228.152.115.0/25228.152.115.1 to 228.152.115.126228.152.115.127126
232228.152.115.128/25228.152.115.129 to 228.152.115.254228.152.115.255126
233228.152.116.0/25228.152.116.1 to 228.152.116.126228.152.116.127126
234228.152.116.128/25228.152.116.129 to 228.152.116.254228.152.116.255126
235228.152.117.0/25228.152.117.1 to 228.152.117.126228.152.117.127126
236228.152.117.128/25228.152.117.129 to 228.152.117.254228.152.117.255126
237228.152.118.0/25228.152.118.1 to 228.152.118.126228.152.118.127126
238228.152.118.128/25228.152.118.129 to 228.152.118.254228.152.118.255126
239228.152.119.0/25228.152.119.1 to 228.152.119.126228.152.119.127126
240228.152.119.128/25228.152.119.129 to 228.152.119.254228.152.119.255126
241228.152.120.0/25228.152.120.1 to 228.152.120.126228.152.120.127126
242228.152.120.128/25228.152.120.129 to 228.152.120.254228.152.120.255126
243228.152.121.0/25228.152.121.1 to 228.152.121.126228.152.121.127126
244228.152.121.128/25228.152.121.129 to 228.152.121.254228.152.121.255126
245228.152.122.0/25228.152.122.1 to 228.152.122.126228.152.122.127126
246228.152.122.128/25228.152.122.129 to 228.152.122.254228.152.122.255126
247228.152.123.0/25228.152.123.1 to 228.152.123.126228.152.123.127126
248228.152.123.128/25228.152.123.129 to 228.152.123.254228.152.123.255126
249228.152.124.0/25228.152.124.1 to 228.152.124.126228.152.124.127126
250228.152.124.128/25228.152.124.129 to 228.152.124.254228.152.124.255126
251228.152.125.0/25228.152.125.1 to 228.152.125.126228.152.125.127126
252228.152.125.128/25228.152.125.129 to 228.152.125.254228.152.125.255126
253228.152.126.0/25228.152.126.1 to 228.152.126.126228.152.126.127126
254228.152.126.128/25228.152.126.129 to 228.152.126.254228.152.126.255126
255228.152.127.0/25228.152.127.1 to 228.152.127.126228.152.127.127126
256228.152.127.128/25228.152.127.129 to 228.152.127.254228.152.127.255126

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.