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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.

Network229.232.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
229.232.0.0
Broadcast address
229.239.255.255
First usable
229.232.0.1
Last usable
229.239.255.254
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 E5E80000 · Integer 3857186816 to 3857711103
Reverse DNS zones
232.229.in-addr.arpa
233.229.in-addr.arpa
234.229.in-addr.arpa
235.229.in-addr.arpa
236.229.in-addr.arpa
237.229.in-addr.arpa
238.229.in-addr.arpa
239.229.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
Address11100101.11101000.00000000.00000000229.232.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network11100101.11101000.00000000.00000000229.232.0.0
Broadcast11100101.11101111.11111111.11111111229.239.255.255
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)

229.232.0.0/13 makes 4,096 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1229.232.0.0/25229.232.0.1 to 229.232.0.126229.232.0.127126
2229.232.0.128/25229.232.0.129 to 229.232.0.254229.232.0.255126
3229.232.1.0/25229.232.1.1 to 229.232.1.126229.232.1.127126
4229.232.1.128/25229.232.1.129 to 229.232.1.254229.232.1.255126
5229.232.2.0/25229.232.2.1 to 229.232.2.126229.232.2.127126
6229.232.2.128/25229.232.2.129 to 229.232.2.254229.232.2.255126
7229.232.3.0/25229.232.3.1 to 229.232.3.126229.232.3.127126
8229.232.3.128/25229.232.3.129 to 229.232.3.254229.232.3.255126
9229.232.4.0/25229.232.4.1 to 229.232.4.126229.232.4.127126
10229.232.4.128/25229.232.4.129 to 229.232.4.254229.232.4.255126
11229.232.5.0/25229.232.5.1 to 229.232.5.126229.232.5.127126
12229.232.5.128/25229.232.5.129 to 229.232.5.254229.232.5.255126
13229.232.6.0/25229.232.6.1 to 229.232.6.126229.232.6.127126
14229.232.6.128/25229.232.6.129 to 229.232.6.254229.232.6.255126
15229.232.7.0/25229.232.7.1 to 229.232.7.126229.232.7.127126
16229.232.7.128/25229.232.7.129 to 229.232.7.254229.232.7.255126
17229.232.8.0/25229.232.8.1 to 229.232.8.126229.232.8.127126
18229.232.8.128/25229.232.8.129 to 229.232.8.254229.232.8.255126
19229.232.9.0/25229.232.9.1 to 229.232.9.126229.232.9.127126
20229.232.9.128/25229.232.9.129 to 229.232.9.254229.232.9.255126
21229.232.10.0/25229.232.10.1 to 229.232.10.126229.232.10.127126
22229.232.10.128/25229.232.10.129 to 229.232.10.254229.232.10.255126
23229.232.11.0/25229.232.11.1 to 229.232.11.126229.232.11.127126
24229.232.11.128/25229.232.11.129 to 229.232.11.254229.232.11.255126
25229.232.12.0/25229.232.12.1 to 229.232.12.126229.232.12.127126
26229.232.12.128/25229.232.12.129 to 229.232.12.254229.232.12.255126
27229.232.13.0/25229.232.13.1 to 229.232.13.126229.232.13.127126
28229.232.13.128/25229.232.13.129 to 229.232.13.254229.232.13.255126
29229.232.14.0/25229.232.14.1 to 229.232.14.126229.232.14.127126
30229.232.14.128/25229.232.14.129 to 229.232.14.254229.232.14.255126
31229.232.15.0/25229.232.15.1 to 229.232.15.126229.232.15.127126
32229.232.15.128/25229.232.15.129 to 229.232.15.254229.232.15.255126
33229.232.16.0/25229.232.16.1 to 229.232.16.126229.232.16.127126
34229.232.16.128/25229.232.16.129 to 229.232.16.254229.232.16.255126
35229.232.17.0/25229.232.17.1 to 229.232.17.126229.232.17.127126
36229.232.17.128/25229.232.17.129 to 229.232.17.254229.232.17.255126
37229.232.18.0/25229.232.18.1 to 229.232.18.126229.232.18.127126
38229.232.18.128/25229.232.18.129 to 229.232.18.254229.232.18.255126
39229.232.19.0/25229.232.19.1 to 229.232.19.126229.232.19.127126
40229.232.19.128/25229.232.19.129 to 229.232.19.254229.232.19.255126
41229.232.20.0/25229.232.20.1 to 229.232.20.126229.232.20.127126
42229.232.20.128/25229.232.20.129 to 229.232.20.254229.232.20.255126
43229.232.21.0/25229.232.21.1 to 229.232.21.126229.232.21.127126
44229.232.21.128/25229.232.21.129 to 229.232.21.254229.232.21.255126
45229.232.22.0/25229.232.22.1 to 229.232.22.126229.232.22.127126
46229.232.22.128/25229.232.22.129 to 229.232.22.254229.232.22.255126
47229.232.23.0/25229.232.23.1 to 229.232.23.126229.232.23.127126
48229.232.23.128/25229.232.23.129 to 229.232.23.254229.232.23.255126
49229.232.24.0/25229.232.24.1 to 229.232.24.126229.232.24.127126
50229.232.24.128/25229.232.24.129 to 229.232.24.254229.232.24.255126
51229.232.25.0/25229.232.25.1 to 229.232.25.126229.232.25.127126
52229.232.25.128/25229.232.25.129 to 229.232.25.254229.232.25.255126
53229.232.26.0/25229.232.26.1 to 229.232.26.126229.232.26.127126
54229.232.26.128/25229.232.26.129 to 229.232.26.254229.232.26.255126
55229.232.27.0/25229.232.27.1 to 229.232.27.126229.232.27.127126
56229.232.27.128/25229.232.27.129 to 229.232.27.254229.232.27.255126
57229.232.28.0/25229.232.28.1 to 229.232.28.126229.232.28.127126
58229.232.28.128/25229.232.28.129 to 229.232.28.254229.232.28.255126
59229.232.29.0/25229.232.29.1 to 229.232.29.126229.232.29.127126
60229.232.29.128/25229.232.29.129 to 229.232.29.254229.232.29.255126
61229.232.30.0/25229.232.30.1 to 229.232.30.126229.232.30.127126
62229.232.30.128/25229.232.30.129 to 229.232.30.254229.232.30.255126
63229.232.31.0/25229.232.31.1 to 229.232.31.126229.232.31.127126
64229.232.31.128/25229.232.31.129 to 229.232.31.254229.232.31.255126
65229.232.32.0/25229.232.32.1 to 229.232.32.126229.232.32.127126
66229.232.32.128/25229.232.32.129 to 229.232.32.254229.232.32.255126
67229.232.33.0/25229.232.33.1 to 229.232.33.126229.232.33.127126
68229.232.33.128/25229.232.33.129 to 229.232.33.254229.232.33.255126
69229.232.34.0/25229.232.34.1 to 229.232.34.126229.232.34.127126
70229.232.34.128/25229.232.34.129 to 229.232.34.254229.232.34.255126
71229.232.35.0/25229.232.35.1 to 229.232.35.126229.232.35.127126
72229.232.35.128/25229.232.35.129 to 229.232.35.254229.232.35.255126
73229.232.36.0/25229.232.36.1 to 229.232.36.126229.232.36.127126
74229.232.36.128/25229.232.36.129 to 229.232.36.254229.232.36.255126
75229.232.37.0/25229.232.37.1 to 229.232.37.126229.232.37.127126
76229.232.37.128/25229.232.37.129 to 229.232.37.254229.232.37.255126
77229.232.38.0/25229.232.38.1 to 229.232.38.126229.232.38.127126
78229.232.38.128/25229.232.38.129 to 229.232.38.254229.232.38.255126
79229.232.39.0/25229.232.39.1 to 229.232.39.126229.232.39.127126
80229.232.39.128/25229.232.39.129 to 229.232.39.254229.232.39.255126
81229.232.40.0/25229.232.40.1 to 229.232.40.126229.232.40.127126
82229.232.40.128/25229.232.40.129 to 229.232.40.254229.232.40.255126
83229.232.41.0/25229.232.41.1 to 229.232.41.126229.232.41.127126
84229.232.41.128/25229.232.41.129 to 229.232.41.254229.232.41.255126
85229.232.42.0/25229.232.42.1 to 229.232.42.126229.232.42.127126
86229.232.42.128/25229.232.42.129 to 229.232.42.254229.232.42.255126
87229.232.43.0/25229.232.43.1 to 229.232.43.126229.232.43.127126
88229.232.43.128/25229.232.43.129 to 229.232.43.254229.232.43.255126
89229.232.44.0/25229.232.44.1 to 229.232.44.126229.232.44.127126
90229.232.44.128/25229.232.44.129 to 229.232.44.254229.232.44.255126
91229.232.45.0/25229.232.45.1 to 229.232.45.126229.232.45.127126
92229.232.45.128/25229.232.45.129 to 229.232.45.254229.232.45.255126
93229.232.46.0/25229.232.46.1 to 229.232.46.126229.232.46.127126
94229.232.46.128/25229.232.46.129 to 229.232.46.254229.232.46.255126
95229.232.47.0/25229.232.47.1 to 229.232.47.126229.232.47.127126
96229.232.47.128/25229.232.47.129 to 229.232.47.254229.232.47.255126
97229.232.48.0/25229.232.48.1 to 229.232.48.126229.232.48.127126
98229.232.48.128/25229.232.48.129 to 229.232.48.254229.232.48.255126
99229.232.49.0/25229.232.49.1 to 229.232.49.126229.232.49.127126
100229.232.49.128/25229.232.49.129 to 229.232.49.254229.232.49.255126
101229.232.50.0/25229.232.50.1 to 229.232.50.126229.232.50.127126
102229.232.50.128/25229.232.50.129 to 229.232.50.254229.232.50.255126
103229.232.51.0/25229.232.51.1 to 229.232.51.126229.232.51.127126
104229.232.51.128/25229.232.51.129 to 229.232.51.254229.232.51.255126
105229.232.52.0/25229.232.52.1 to 229.232.52.126229.232.52.127126
106229.232.52.128/25229.232.52.129 to 229.232.52.254229.232.52.255126
107229.232.53.0/25229.232.53.1 to 229.232.53.126229.232.53.127126
108229.232.53.128/25229.232.53.129 to 229.232.53.254229.232.53.255126
109229.232.54.0/25229.232.54.1 to 229.232.54.126229.232.54.127126
110229.232.54.128/25229.232.54.129 to 229.232.54.254229.232.54.255126
111229.232.55.0/25229.232.55.1 to 229.232.55.126229.232.55.127126
112229.232.55.128/25229.232.55.129 to 229.232.55.254229.232.55.255126
113229.232.56.0/25229.232.56.1 to 229.232.56.126229.232.56.127126
114229.232.56.128/25229.232.56.129 to 229.232.56.254229.232.56.255126
115229.232.57.0/25229.232.57.1 to 229.232.57.126229.232.57.127126
116229.232.57.128/25229.232.57.129 to 229.232.57.254229.232.57.255126
117229.232.58.0/25229.232.58.1 to 229.232.58.126229.232.58.127126
118229.232.58.128/25229.232.58.129 to 229.232.58.254229.232.58.255126
119229.232.59.0/25229.232.59.1 to 229.232.59.126229.232.59.127126
120229.232.59.128/25229.232.59.129 to 229.232.59.254229.232.59.255126
121229.232.60.0/25229.232.60.1 to 229.232.60.126229.232.60.127126
122229.232.60.128/25229.232.60.129 to 229.232.60.254229.232.60.255126
123229.232.61.0/25229.232.61.1 to 229.232.61.126229.232.61.127126
124229.232.61.128/25229.232.61.129 to 229.232.61.254229.232.61.255126
125229.232.62.0/25229.232.62.1 to 229.232.62.126229.232.62.127126
126229.232.62.128/25229.232.62.129 to 229.232.62.254229.232.62.255126
127229.232.63.0/25229.232.63.1 to 229.232.63.126229.232.63.127126
128229.232.63.128/25229.232.63.129 to 229.232.63.254229.232.63.255126
129229.232.64.0/25229.232.64.1 to 229.232.64.126229.232.64.127126
130229.232.64.128/25229.232.64.129 to 229.232.64.254229.232.64.255126
131229.232.65.0/25229.232.65.1 to 229.232.65.126229.232.65.127126
132229.232.65.128/25229.232.65.129 to 229.232.65.254229.232.65.255126
133229.232.66.0/25229.232.66.1 to 229.232.66.126229.232.66.127126
134229.232.66.128/25229.232.66.129 to 229.232.66.254229.232.66.255126
135229.232.67.0/25229.232.67.1 to 229.232.67.126229.232.67.127126
136229.232.67.128/25229.232.67.129 to 229.232.67.254229.232.67.255126
137229.232.68.0/25229.232.68.1 to 229.232.68.126229.232.68.127126
138229.232.68.128/25229.232.68.129 to 229.232.68.254229.232.68.255126
139229.232.69.0/25229.232.69.1 to 229.232.69.126229.232.69.127126
140229.232.69.128/25229.232.69.129 to 229.232.69.254229.232.69.255126
141229.232.70.0/25229.232.70.1 to 229.232.70.126229.232.70.127126
142229.232.70.128/25229.232.70.129 to 229.232.70.254229.232.70.255126
143229.232.71.0/25229.232.71.1 to 229.232.71.126229.232.71.127126
144229.232.71.128/25229.232.71.129 to 229.232.71.254229.232.71.255126
145229.232.72.0/25229.232.72.1 to 229.232.72.126229.232.72.127126
146229.232.72.128/25229.232.72.129 to 229.232.72.254229.232.72.255126
147229.232.73.0/25229.232.73.1 to 229.232.73.126229.232.73.127126
148229.232.73.128/25229.232.73.129 to 229.232.73.254229.232.73.255126
149229.232.74.0/25229.232.74.1 to 229.232.74.126229.232.74.127126
150229.232.74.128/25229.232.74.129 to 229.232.74.254229.232.74.255126
151229.232.75.0/25229.232.75.1 to 229.232.75.126229.232.75.127126
152229.232.75.128/25229.232.75.129 to 229.232.75.254229.232.75.255126
153229.232.76.0/25229.232.76.1 to 229.232.76.126229.232.76.127126
154229.232.76.128/25229.232.76.129 to 229.232.76.254229.232.76.255126
155229.232.77.0/25229.232.77.1 to 229.232.77.126229.232.77.127126
156229.232.77.128/25229.232.77.129 to 229.232.77.254229.232.77.255126
157229.232.78.0/25229.232.78.1 to 229.232.78.126229.232.78.127126
158229.232.78.128/25229.232.78.129 to 229.232.78.254229.232.78.255126
159229.232.79.0/25229.232.79.1 to 229.232.79.126229.232.79.127126
160229.232.79.128/25229.232.79.129 to 229.232.79.254229.232.79.255126
161229.232.80.0/25229.232.80.1 to 229.232.80.126229.232.80.127126
162229.232.80.128/25229.232.80.129 to 229.232.80.254229.232.80.255126
163229.232.81.0/25229.232.81.1 to 229.232.81.126229.232.81.127126
164229.232.81.128/25229.232.81.129 to 229.232.81.254229.232.81.255126
165229.232.82.0/25229.232.82.1 to 229.232.82.126229.232.82.127126
166229.232.82.128/25229.232.82.129 to 229.232.82.254229.232.82.255126
167229.232.83.0/25229.232.83.1 to 229.232.83.126229.232.83.127126
168229.232.83.128/25229.232.83.129 to 229.232.83.254229.232.83.255126
169229.232.84.0/25229.232.84.1 to 229.232.84.126229.232.84.127126
170229.232.84.128/25229.232.84.129 to 229.232.84.254229.232.84.255126
171229.232.85.0/25229.232.85.1 to 229.232.85.126229.232.85.127126
172229.232.85.128/25229.232.85.129 to 229.232.85.254229.232.85.255126
173229.232.86.0/25229.232.86.1 to 229.232.86.126229.232.86.127126
174229.232.86.128/25229.232.86.129 to 229.232.86.254229.232.86.255126
175229.232.87.0/25229.232.87.1 to 229.232.87.126229.232.87.127126
176229.232.87.128/25229.232.87.129 to 229.232.87.254229.232.87.255126
177229.232.88.0/25229.232.88.1 to 229.232.88.126229.232.88.127126
178229.232.88.128/25229.232.88.129 to 229.232.88.254229.232.88.255126
179229.232.89.0/25229.232.89.1 to 229.232.89.126229.232.89.127126
180229.232.89.128/25229.232.89.129 to 229.232.89.254229.232.89.255126
181229.232.90.0/25229.232.90.1 to 229.232.90.126229.232.90.127126
182229.232.90.128/25229.232.90.129 to 229.232.90.254229.232.90.255126
183229.232.91.0/25229.232.91.1 to 229.232.91.126229.232.91.127126
184229.232.91.128/25229.232.91.129 to 229.232.91.254229.232.91.255126
185229.232.92.0/25229.232.92.1 to 229.232.92.126229.232.92.127126
186229.232.92.128/25229.232.92.129 to 229.232.92.254229.232.92.255126
187229.232.93.0/25229.232.93.1 to 229.232.93.126229.232.93.127126
188229.232.93.128/25229.232.93.129 to 229.232.93.254229.232.93.255126
189229.232.94.0/25229.232.94.1 to 229.232.94.126229.232.94.127126
190229.232.94.128/25229.232.94.129 to 229.232.94.254229.232.94.255126
191229.232.95.0/25229.232.95.1 to 229.232.95.126229.232.95.127126
192229.232.95.128/25229.232.95.129 to 229.232.95.254229.232.95.255126
193229.232.96.0/25229.232.96.1 to 229.232.96.126229.232.96.127126
194229.232.96.128/25229.232.96.129 to 229.232.96.254229.232.96.255126
195229.232.97.0/25229.232.97.1 to 229.232.97.126229.232.97.127126
196229.232.97.128/25229.232.97.129 to 229.232.97.254229.232.97.255126
197229.232.98.0/25229.232.98.1 to 229.232.98.126229.232.98.127126
198229.232.98.128/25229.232.98.129 to 229.232.98.254229.232.98.255126
199229.232.99.0/25229.232.99.1 to 229.232.99.126229.232.99.127126
200229.232.99.128/25229.232.99.129 to 229.232.99.254229.232.99.255126
201229.232.100.0/25229.232.100.1 to 229.232.100.126229.232.100.127126
202229.232.100.128/25229.232.100.129 to 229.232.100.254229.232.100.255126
203229.232.101.0/25229.232.101.1 to 229.232.101.126229.232.101.127126
204229.232.101.128/25229.232.101.129 to 229.232.101.254229.232.101.255126
205229.232.102.0/25229.232.102.1 to 229.232.102.126229.232.102.127126
206229.232.102.128/25229.232.102.129 to 229.232.102.254229.232.102.255126
207229.232.103.0/25229.232.103.1 to 229.232.103.126229.232.103.127126
208229.232.103.128/25229.232.103.129 to 229.232.103.254229.232.103.255126
209229.232.104.0/25229.232.104.1 to 229.232.104.126229.232.104.127126
210229.232.104.128/25229.232.104.129 to 229.232.104.254229.232.104.255126
211229.232.105.0/25229.232.105.1 to 229.232.105.126229.232.105.127126
212229.232.105.128/25229.232.105.129 to 229.232.105.254229.232.105.255126
213229.232.106.0/25229.232.106.1 to 229.232.106.126229.232.106.127126
214229.232.106.128/25229.232.106.129 to 229.232.106.254229.232.106.255126
215229.232.107.0/25229.232.107.1 to 229.232.107.126229.232.107.127126
216229.232.107.128/25229.232.107.129 to 229.232.107.254229.232.107.255126
217229.232.108.0/25229.232.108.1 to 229.232.108.126229.232.108.127126
218229.232.108.128/25229.232.108.129 to 229.232.108.254229.232.108.255126
219229.232.109.0/25229.232.109.1 to 229.232.109.126229.232.109.127126
220229.232.109.128/25229.232.109.129 to 229.232.109.254229.232.109.255126
221229.232.110.0/25229.232.110.1 to 229.232.110.126229.232.110.127126
222229.232.110.128/25229.232.110.129 to 229.232.110.254229.232.110.255126
223229.232.111.0/25229.232.111.1 to 229.232.111.126229.232.111.127126
224229.232.111.128/25229.232.111.129 to 229.232.111.254229.232.111.255126
225229.232.112.0/25229.232.112.1 to 229.232.112.126229.232.112.127126
226229.232.112.128/25229.232.112.129 to 229.232.112.254229.232.112.255126
227229.232.113.0/25229.232.113.1 to 229.232.113.126229.232.113.127126
228229.232.113.128/25229.232.113.129 to 229.232.113.254229.232.113.255126
229229.232.114.0/25229.232.114.1 to 229.232.114.126229.232.114.127126
230229.232.114.128/25229.232.114.129 to 229.232.114.254229.232.114.255126
231229.232.115.0/25229.232.115.1 to 229.232.115.126229.232.115.127126
232229.232.115.128/25229.232.115.129 to 229.232.115.254229.232.115.255126
233229.232.116.0/25229.232.116.1 to 229.232.116.126229.232.116.127126
234229.232.116.128/25229.232.116.129 to 229.232.116.254229.232.116.255126
235229.232.117.0/25229.232.117.1 to 229.232.117.126229.232.117.127126
236229.232.117.128/25229.232.117.129 to 229.232.117.254229.232.117.255126
237229.232.118.0/25229.232.118.1 to 229.232.118.126229.232.118.127126
238229.232.118.128/25229.232.118.129 to 229.232.118.254229.232.118.255126
239229.232.119.0/25229.232.119.1 to 229.232.119.126229.232.119.127126
240229.232.119.128/25229.232.119.129 to 229.232.119.254229.232.119.255126
241229.232.120.0/25229.232.120.1 to 229.232.120.126229.232.120.127126
242229.232.120.128/25229.232.120.129 to 229.232.120.254229.232.120.255126
243229.232.121.0/25229.232.121.1 to 229.232.121.126229.232.121.127126
244229.232.121.128/25229.232.121.129 to 229.232.121.254229.232.121.255126
245229.232.122.0/25229.232.122.1 to 229.232.122.126229.232.122.127126
246229.232.122.128/25229.232.122.129 to 229.232.122.254229.232.122.255126
247229.232.123.0/25229.232.123.1 to 229.232.123.126229.232.123.127126
248229.232.123.128/25229.232.123.129 to 229.232.123.254229.232.123.255126
249229.232.124.0/25229.232.124.1 to 229.232.124.126229.232.124.127126
250229.232.124.128/25229.232.124.129 to 229.232.124.254229.232.124.255126
251229.232.125.0/25229.232.125.1 to 229.232.125.126229.232.125.127126
252229.232.125.128/25229.232.125.129 to 229.232.125.254229.232.125.255126
253229.232.126.0/25229.232.126.1 to 229.232.126.126229.232.126.127126
254229.232.126.128/25229.232.126.129 to 229.232.126.254229.232.126.255126
255229.232.127.0/25229.232.127.1 to 229.232.127.126229.232.127.127126
256229.232.127.128/25229.232.127.129 to 229.232.127.254229.232.127.255126

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.