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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.

Network200.232.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
200.232.0.0
Broadcast address
200.239.255.255
First usable
200.232.0.1
Last usable
200.239.255.254
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
Public public
Old class
C (default /24)
As numbers
Hex C8E80000 · Integer 3370647552 to 3371171839
Reverse DNS zones
232.200.in-addr.arpa
233.200.in-addr.arpa
234.200.in-addr.arpa
235.200.in-addr.arpa
236.200.in-addr.arpa
237.200.in-addr.arpa
238.200.in-addr.arpa
239.200.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
Address11001000.11101000.00000000.00000000200.232.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network11001000.11101000.00000000.00000000200.232.0.0
Broadcast11001000.11101111.11111111.11111111200.239.255.255
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)

200.232.0.0/13 makes 4,096 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1200.232.0.0/25200.232.0.1 to 200.232.0.126200.232.0.127126
2200.232.0.128/25200.232.0.129 to 200.232.0.254200.232.0.255126
3200.232.1.0/25200.232.1.1 to 200.232.1.126200.232.1.127126
4200.232.1.128/25200.232.1.129 to 200.232.1.254200.232.1.255126
5200.232.2.0/25200.232.2.1 to 200.232.2.126200.232.2.127126
6200.232.2.128/25200.232.2.129 to 200.232.2.254200.232.2.255126
7200.232.3.0/25200.232.3.1 to 200.232.3.126200.232.3.127126
8200.232.3.128/25200.232.3.129 to 200.232.3.254200.232.3.255126
9200.232.4.0/25200.232.4.1 to 200.232.4.126200.232.4.127126
10200.232.4.128/25200.232.4.129 to 200.232.4.254200.232.4.255126
11200.232.5.0/25200.232.5.1 to 200.232.5.126200.232.5.127126
12200.232.5.128/25200.232.5.129 to 200.232.5.254200.232.5.255126
13200.232.6.0/25200.232.6.1 to 200.232.6.126200.232.6.127126
14200.232.6.128/25200.232.6.129 to 200.232.6.254200.232.6.255126
15200.232.7.0/25200.232.7.1 to 200.232.7.126200.232.7.127126
16200.232.7.128/25200.232.7.129 to 200.232.7.254200.232.7.255126
17200.232.8.0/25200.232.8.1 to 200.232.8.126200.232.8.127126
18200.232.8.128/25200.232.8.129 to 200.232.8.254200.232.8.255126
19200.232.9.0/25200.232.9.1 to 200.232.9.126200.232.9.127126
20200.232.9.128/25200.232.9.129 to 200.232.9.254200.232.9.255126
21200.232.10.0/25200.232.10.1 to 200.232.10.126200.232.10.127126
22200.232.10.128/25200.232.10.129 to 200.232.10.254200.232.10.255126
23200.232.11.0/25200.232.11.1 to 200.232.11.126200.232.11.127126
24200.232.11.128/25200.232.11.129 to 200.232.11.254200.232.11.255126
25200.232.12.0/25200.232.12.1 to 200.232.12.126200.232.12.127126
26200.232.12.128/25200.232.12.129 to 200.232.12.254200.232.12.255126
27200.232.13.0/25200.232.13.1 to 200.232.13.126200.232.13.127126
28200.232.13.128/25200.232.13.129 to 200.232.13.254200.232.13.255126
29200.232.14.0/25200.232.14.1 to 200.232.14.126200.232.14.127126
30200.232.14.128/25200.232.14.129 to 200.232.14.254200.232.14.255126
31200.232.15.0/25200.232.15.1 to 200.232.15.126200.232.15.127126
32200.232.15.128/25200.232.15.129 to 200.232.15.254200.232.15.255126
33200.232.16.0/25200.232.16.1 to 200.232.16.126200.232.16.127126
34200.232.16.128/25200.232.16.129 to 200.232.16.254200.232.16.255126
35200.232.17.0/25200.232.17.1 to 200.232.17.126200.232.17.127126
36200.232.17.128/25200.232.17.129 to 200.232.17.254200.232.17.255126
37200.232.18.0/25200.232.18.1 to 200.232.18.126200.232.18.127126
38200.232.18.128/25200.232.18.129 to 200.232.18.254200.232.18.255126
39200.232.19.0/25200.232.19.1 to 200.232.19.126200.232.19.127126
40200.232.19.128/25200.232.19.129 to 200.232.19.254200.232.19.255126
41200.232.20.0/25200.232.20.1 to 200.232.20.126200.232.20.127126
42200.232.20.128/25200.232.20.129 to 200.232.20.254200.232.20.255126
43200.232.21.0/25200.232.21.1 to 200.232.21.126200.232.21.127126
44200.232.21.128/25200.232.21.129 to 200.232.21.254200.232.21.255126
45200.232.22.0/25200.232.22.1 to 200.232.22.126200.232.22.127126
46200.232.22.128/25200.232.22.129 to 200.232.22.254200.232.22.255126
47200.232.23.0/25200.232.23.1 to 200.232.23.126200.232.23.127126
48200.232.23.128/25200.232.23.129 to 200.232.23.254200.232.23.255126
49200.232.24.0/25200.232.24.1 to 200.232.24.126200.232.24.127126
50200.232.24.128/25200.232.24.129 to 200.232.24.254200.232.24.255126
51200.232.25.0/25200.232.25.1 to 200.232.25.126200.232.25.127126
52200.232.25.128/25200.232.25.129 to 200.232.25.254200.232.25.255126
53200.232.26.0/25200.232.26.1 to 200.232.26.126200.232.26.127126
54200.232.26.128/25200.232.26.129 to 200.232.26.254200.232.26.255126
55200.232.27.0/25200.232.27.1 to 200.232.27.126200.232.27.127126
56200.232.27.128/25200.232.27.129 to 200.232.27.254200.232.27.255126
57200.232.28.0/25200.232.28.1 to 200.232.28.126200.232.28.127126
58200.232.28.128/25200.232.28.129 to 200.232.28.254200.232.28.255126
59200.232.29.0/25200.232.29.1 to 200.232.29.126200.232.29.127126
60200.232.29.128/25200.232.29.129 to 200.232.29.254200.232.29.255126
61200.232.30.0/25200.232.30.1 to 200.232.30.126200.232.30.127126
62200.232.30.128/25200.232.30.129 to 200.232.30.254200.232.30.255126
63200.232.31.0/25200.232.31.1 to 200.232.31.126200.232.31.127126
64200.232.31.128/25200.232.31.129 to 200.232.31.254200.232.31.255126
65200.232.32.0/25200.232.32.1 to 200.232.32.126200.232.32.127126
66200.232.32.128/25200.232.32.129 to 200.232.32.254200.232.32.255126
67200.232.33.0/25200.232.33.1 to 200.232.33.126200.232.33.127126
68200.232.33.128/25200.232.33.129 to 200.232.33.254200.232.33.255126
69200.232.34.0/25200.232.34.1 to 200.232.34.126200.232.34.127126
70200.232.34.128/25200.232.34.129 to 200.232.34.254200.232.34.255126
71200.232.35.0/25200.232.35.1 to 200.232.35.126200.232.35.127126
72200.232.35.128/25200.232.35.129 to 200.232.35.254200.232.35.255126
73200.232.36.0/25200.232.36.1 to 200.232.36.126200.232.36.127126
74200.232.36.128/25200.232.36.129 to 200.232.36.254200.232.36.255126
75200.232.37.0/25200.232.37.1 to 200.232.37.126200.232.37.127126
76200.232.37.128/25200.232.37.129 to 200.232.37.254200.232.37.255126
77200.232.38.0/25200.232.38.1 to 200.232.38.126200.232.38.127126
78200.232.38.128/25200.232.38.129 to 200.232.38.254200.232.38.255126
79200.232.39.0/25200.232.39.1 to 200.232.39.126200.232.39.127126
80200.232.39.128/25200.232.39.129 to 200.232.39.254200.232.39.255126
81200.232.40.0/25200.232.40.1 to 200.232.40.126200.232.40.127126
82200.232.40.128/25200.232.40.129 to 200.232.40.254200.232.40.255126
83200.232.41.0/25200.232.41.1 to 200.232.41.126200.232.41.127126
84200.232.41.128/25200.232.41.129 to 200.232.41.254200.232.41.255126
85200.232.42.0/25200.232.42.1 to 200.232.42.126200.232.42.127126
86200.232.42.128/25200.232.42.129 to 200.232.42.254200.232.42.255126
87200.232.43.0/25200.232.43.1 to 200.232.43.126200.232.43.127126
88200.232.43.128/25200.232.43.129 to 200.232.43.254200.232.43.255126
89200.232.44.0/25200.232.44.1 to 200.232.44.126200.232.44.127126
90200.232.44.128/25200.232.44.129 to 200.232.44.254200.232.44.255126
91200.232.45.0/25200.232.45.1 to 200.232.45.126200.232.45.127126
92200.232.45.128/25200.232.45.129 to 200.232.45.254200.232.45.255126
93200.232.46.0/25200.232.46.1 to 200.232.46.126200.232.46.127126
94200.232.46.128/25200.232.46.129 to 200.232.46.254200.232.46.255126
95200.232.47.0/25200.232.47.1 to 200.232.47.126200.232.47.127126
96200.232.47.128/25200.232.47.129 to 200.232.47.254200.232.47.255126
97200.232.48.0/25200.232.48.1 to 200.232.48.126200.232.48.127126
98200.232.48.128/25200.232.48.129 to 200.232.48.254200.232.48.255126
99200.232.49.0/25200.232.49.1 to 200.232.49.126200.232.49.127126
100200.232.49.128/25200.232.49.129 to 200.232.49.254200.232.49.255126
101200.232.50.0/25200.232.50.1 to 200.232.50.126200.232.50.127126
102200.232.50.128/25200.232.50.129 to 200.232.50.254200.232.50.255126
103200.232.51.0/25200.232.51.1 to 200.232.51.126200.232.51.127126
104200.232.51.128/25200.232.51.129 to 200.232.51.254200.232.51.255126
105200.232.52.0/25200.232.52.1 to 200.232.52.126200.232.52.127126
106200.232.52.128/25200.232.52.129 to 200.232.52.254200.232.52.255126
107200.232.53.0/25200.232.53.1 to 200.232.53.126200.232.53.127126
108200.232.53.128/25200.232.53.129 to 200.232.53.254200.232.53.255126
109200.232.54.0/25200.232.54.1 to 200.232.54.126200.232.54.127126
110200.232.54.128/25200.232.54.129 to 200.232.54.254200.232.54.255126
111200.232.55.0/25200.232.55.1 to 200.232.55.126200.232.55.127126
112200.232.55.128/25200.232.55.129 to 200.232.55.254200.232.55.255126
113200.232.56.0/25200.232.56.1 to 200.232.56.126200.232.56.127126
114200.232.56.128/25200.232.56.129 to 200.232.56.254200.232.56.255126
115200.232.57.0/25200.232.57.1 to 200.232.57.126200.232.57.127126
116200.232.57.128/25200.232.57.129 to 200.232.57.254200.232.57.255126
117200.232.58.0/25200.232.58.1 to 200.232.58.126200.232.58.127126
118200.232.58.128/25200.232.58.129 to 200.232.58.254200.232.58.255126
119200.232.59.0/25200.232.59.1 to 200.232.59.126200.232.59.127126
120200.232.59.128/25200.232.59.129 to 200.232.59.254200.232.59.255126
121200.232.60.0/25200.232.60.1 to 200.232.60.126200.232.60.127126
122200.232.60.128/25200.232.60.129 to 200.232.60.254200.232.60.255126
123200.232.61.0/25200.232.61.1 to 200.232.61.126200.232.61.127126
124200.232.61.128/25200.232.61.129 to 200.232.61.254200.232.61.255126
125200.232.62.0/25200.232.62.1 to 200.232.62.126200.232.62.127126
126200.232.62.128/25200.232.62.129 to 200.232.62.254200.232.62.255126
127200.232.63.0/25200.232.63.1 to 200.232.63.126200.232.63.127126
128200.232.63.128/25200.232.63.129 to 200.232.63.254200.232.63.255126
129200.232.64.0/25200.232.64.1 to 200.232.64.126200.232.64.127126
130200.232.64.128/25200.232.64.129 to 200.232.64.254200.232.64.255126
131200.232.65.0/25200.232.65.1 to 200.232.65.126200.232.65.127126
132200.232.65.128/25200.232.65.129 to 200.232.65.254200.232.65.255126
133200.232.66.0/25200.232.66.1 to 200.232.66.126200.232.66.127126
134200.232.66.128/25200.232.66.129 to 200.232.66.254200.232.66.255126
135200.232.67.0/25200.232.67.1 to 200.232.67.126200.232.67.127126
136200.232.67.128/25200.232.67.129 to 200.232.67.254200.232.67.255126
137200.232.68.0/25200.232.68.1 to 200.232.68.126200.232.68.127126
138200.232.68.128/25200.232.68.129 to 200.232.68.254200.232.68.255126
139200.232.69.0/25200.232.69.1 to 200.232.69.126200.232.69.127126
140200.232.69.128/25200.232.69.129 to 200.232.69.254200.232.69.255126
141200.232.70.0/25200.232.70.1 to 200.232.70.126200.232.70.127126
142200.232.70.128/25200.232.70.129 to 200.232.70.254200.232.70.255126
143200.232.71.0/25200.232.71.1 to 200.232.71.126200.232.71.127126
144200.232.71.128/25200.232.71.129 to 200.232.71.254200.232.71.255126
145200.232.72.0/25200.232.72.1 to 200.232.72.126200.232.72.127126
146200.232.72.128/25200.232.72.129 to 200.232.72.254200.232.72.255126
147200.232.73.0/25200.232.73.1 to 200.232.73.126200.232.73.127126
148200.232.73.128/25200.232.73.129 to 200.232.73.254200.232.73.255126
149200.232.74.0/25200.232.74.1 to 200.232.74.126200.232.74.127126
150200.232.74.128/25200.232.74.129 to 200.232.74.254200.232.74.255126
151200.232.75.0/25200.232.75.1 to 200.232.75.126200.232.75.127126
152200.232.75.128/25200.232.75.129 to 200.232.75.254200.232.75.255126
153200.232.76.0/25200.232.76.1 to 200.232.76.126200.232.76.127126
154200.232.76.128/25200.232.76.129 to 200.232.76.254200.232.76.255126
155200.232.77.0/25200.232.77.1 to 200.232.77.126200.232.77.127126
156200.232.77.128/25200.232.77.129 to 200.232.77.254200.232.77.255126
157200.232.78.0/25200.232.78.1 to 200.232.78.126200.232.78.127126
158200.232.78.128/25200.232.78.129 to 200.232.78.254200.232.78.255126
159200.232.79.0/25200.232.79.1 to 200.232.79.126200.232.79.127126
160200.232.79.128/25200.232.79.129 to 200.232.79.254200.232.79.255126
161200.232.80.0/25200.232.80.1 to 200.232.80.126200.232.80.127126
162200.232.80.128/25200.232.80.129 to 200.232.80.254200.232.80.255126
163200.232.81.0/25200.232.81.1 to 200.232.81.126200.232.81.127126
164200.232.81.128/25200.232.81.129 to 200.232.81.254200.232.81.255126
165200.232.82.0/25200.232.82.1 to 200.232.82.126200.232.82.127126
166200.232.82.128/25200.232.82.129 to 200.232.82.254200.232.82.255126
167200.232.83.0/25200.232.83.1 to 200.232.83.126200.232.83.127126
168200.232.83.128/25200.232.83.129 to 200.232.83.254200.232.83.255126
169200.232.84.0/25200.232.84.1 to 200.232.84.126200.232.84.127126
170200.232.84.128/25200.232.84.129 to 200.232.84.254200.232.84.255126
171200.232.85.0/25200.232.85.1 to 200.232.85.126200.232.85.127126
172200.232.85.128/25200.232.85.129 to 200.232.85.254200.232.85.255126
173200.232.86.0/25200.232.86.1 to 200.232.86.126200.232.86.127126
174200.232.86.128/25200.232.86.129 to 200.232.86.254200.232.86.255126
175200.232.87.0/25200.232.87.1 to 200.232.87.126200.232.87.127126
176200.232.87.128/25200.232.87.129 to 200.232.87.254200.232.87.255126
177200.232.88.0/25200.232.88.1 to 200.232.88.126200.232.88.127126
178200.232.88.128/25200.232.88.129 to 200.232.88.254200.232.88.255126
179200.232.89.0/25200.232.89.1 to 200.232.89.126200.232.89.127126
180200.232.89.128/25200.232.89.129 to 200.232.89.254200.232.89.255126
181200.232.90.0/25200.232.90.1 to 200.232.90.126200.232.90.127126
182200.232.90.128/25200.232.90.129 to 200.232.90.254200.232.90.255126
183200.232.91.0/25200.232.91.1 to 200.232.91.126200.232.91.127126
184200.232.91.128/25200.232.91.129 to 200.232.91.254200.232.91.255126
185200.232.92.0/25200.232.92.1 to 200.232.92.126200.232.92.127126
186200.232.92.128/25200.232.92.129 to 200.232.92.254200.232.92.255126
187200.232.93.0/25200.232.93.1 to 200.232.93.126200.232.93.127126
188200.232.93.128/25200.232.93.129 to 200.232.93.254200.232.93.255126
189200.232.94.0/25200.232.94.1 to 200.232.94.126200.232.94.127126
190200.232.94.128/25200.232.94.129 to 200.232.94.254200.232.94.255126
191200.232.95.0/25200.232.95.1 to 200.232.95.126200.232.95.127126
192200.232.95.128/25200.232.95.129 to 200.232.95.254200.232.95.255126
193200.232.96.0/25200.232.96.1 to 200.232.96.126200.232.96.127126
194200.232.96.128/25200.232.96.129 to 200.232.96.254200.232.96.255126
195200.232.97.0/25200.232.97.1 to 200.232.97.126200.232.97.127126
196200.232.97.128/25200.232.97.129 to 200.232.97.254200.232.97.255126
197200.232.98.0/25200.232.98.1 to 200.232.98.126200.232.98.127126
198200.232.98.128/25200.232.98.129 to 200.232.98.254200.232.98.255126
199200.232.99.0/25200.232.99.1 to 200.232.99.126200.232.99.127126
200200.232.99.128/25200.232.99.129 to 200.232.99.254200.232.99.255126
201200.232.100.0/25200.232.100.1 to 200.232.100.126200.232.100.127126
202200.232.100.128/25200.232.100.129 to 200.232.100.254200.232.100.255126
203200.232.101.0/25200.232.101.1 to 200.232.101.126200.232.101.127126
204200.232.101.128/25200.232.101.129 to 200.232.101.254200.232.101.255126
205200.232.102.0/25200.232.102.1 to 200.232.102.126200.232.102.127126
206200.232.102.128/25200.232.102.129 to 200.232.102.254200.232.102.255126
207200.232.103.0/25200.232.103.1 to 200.232.103.126200.232.103.127126
208200.232.103.128/25200.232.103.129 to 200.232.103.254200.232.103.255126
209200.232.104.0/25200.232.104.1 to 200.232.104.126200.232.104.127126
210200.232.104.128/25200.232.104.129 to 200.232.104.254200.232.104.255126
211200.232.105.0/25200.232.105.1 to 200.232.105.126200.232.105.127126
212200.232.105.128/25200.232.105.129 to 200.232.105.254200.232.105.255126
213200.232.106.0/25200.232.106.1 to 200.232.106.126200.232.106.127126
214200.232.106.128/25200.232.106.129 to 200.232.106.254200.232.106.255126
215200.232.107.0/25200.232.107.1 to 200.232.107.126200.232.107.127126
216200.232.107.128/25200.232.107.129 to 200.232.107.254200.232.107.255126
217200.232.108.0/25200.232.108.1 to 200.232.108.126200.232.108.127126
218200.232.108.128/25200.232.108.129 to 200.232.108.254200.232.108.255126
219200.232.109.0/25200.232.109.1 to 200.232.109.126200.232.109.127126
220200.232.109.128/25200.232.109.129 to 200.232.109.254200.232.109.255126
221200.232.110.0/25200.232.110.1 to 200.232.110.126200.232.110.127126
222200.232.110.128/25200.232.110.129 to 200.232.110.254200.232.110.255126
223200.232.111.0/25200.232.111.1 to 200.232.111.126200.232.111.127126
224200.232.111.128/25200.232.111.129 to 200.232.111.254200.232.111.255126
225200.232.112.0/25200.232.112.1 to 200.232.112.126200.232.112.127126
226200.232.112.128/25200.232.112.129 to 200.232.112.254200.232.112.255126
227200.232.113.0/25200.232.113.1 to 200.232.113.126200.232.113.127126
228200.232.113.128/25200.232.113.129 to 200.232.113.254200.232.113.255126
229200.232.114.0/25200.232.114.1 to 200.232.114.126200.232.114.127126
230200.232.114.128/25200.232.114.129 to 200.232.114.254200.232.114.255126
231200.232.115.0/25200.232.115.1 to 200.232.115.126200.232.115.127126
232200.232.115.128/25200.232.115.129 to 200.232.115.254200.232.115.255126
233200.232.116.0/25200.232.116.1 to 200.232.116.126200.232.116.127126
234200.232.116.128/25200.232.116.129 to 200.232.116.254200.232.116.255126
235200.232.117.0/25200.232.117.1 to 200.232.117.126200.232.117.127126
236200.232.117.128/25200.232.117.129 to 200.232.117.254200.232.117.255126
237200.232.118.0/25200.232.118.1 to 200.232.118.126200.232.118.127126
238200.232.118.128/25200.232.118.129 to 200.232.118.254200.232.118.255126
239200.232.119.0/25200.232.119.1 to 200.232.119.126200.232.119.127126
240200.232.119.128/25200.232.119.129 to 200.232.119.254200.232.119.255126
241200.232.120.0/25200.232.120.1 to 200.232.120.126200.232.120.127126
242200.232.120.128/25200.232.120.129 to 200.232.120.254200.232.120.255126
243200.232.121.0/25200.232.121.1 to 200.232.121.126200.232.121.127126
244200.232.121.128/25200.232.121.129 to 200.232.121.254200.232.121.255126
245200.232.122.0/25200.232.122.1 to 200.232.122.126200.232.122.127126
246200.232.122.128/25200.232.122.129 to 200.232.122.254200.232.122.255126
247200.232.123.0/25200.232.123.1 to 200.232.123.126200.232.123.127126
248200.232.123.128/25200.232.123.129 to 200.232.123.254200.232.123.255126
249200.232.124.0/25200.232.124.1 to 200.232.124.126200.232.124.127126
250200.232.124.128/25200.232.124.129 to 200.232.124.254200.232.124.255126
251200.232.125.0/25200.232.125.1 to 200.232.125.126200.232.125.127126
252200.232.125.128/25200.232.125.129 to 200.232.125.254200.232.125.255126
253200.232.126.0/25200.232.126.1 to 200.232.126.126200.232.126.127126
254200.232.126.128/25200.232.126.129 to 200.232.126.254200.232.126.255126
255200.232.127.0/25200.232.127.1 to 200.232.127.126200.232.127.127126
256200.232.127.128/25200.232.127.129 to 200.232.127.254200.232.127.255126

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.