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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.

Network226.72.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
226.72.0.0
Broadcast address
226.75.255.255
First usable
226.72.0.1
Last usable
226.75.255.254
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
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E2480000 · Integer 3796369408 to 3796631551
Reverse DNS zones
72.226.in-addr.arpa
73.226.in-addr.arpa
74.226.in-addr.arpa
75.226.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
Address11100010.01001000.00000000.00000000226.72.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network11100010.01001000.00000000.00000000226.72.0.0
Broadcast11100010.01001011.11111111.11111111226.75.255.255
Split into smaller subnets/26
/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)

226.72.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1226.72.0.0/26226.72.0.1 to 226.72.0.62226.72.0.6362
2226.72.0.64/26226.72.0.65 to 226.72.0.126226.72.0.12762
3226.72.0.128/26226.72.0.129 to 226.72.0.190226.72.0.19162
4226.72.0.192/26226.72.0.193 to 226.72.0.254226.72.0.25562
5226.72.1.0/26226.72.1.1 to 226.72.1.62226.72.1.6362
6226.72.1.64/26226.72.1.65 to 226.72.1.126226.72.1.12762
7226.72.1.128/26226.72.1.129 to 226.72.1.190226.72.1.19162
8226.72.1.192/26226.72.1.193 to 226.72.1.254226.72.1.25562
9226.72.2.0/26226.72.2.1 to 226.72.2.62226.72.2.6362
10226.72.2.64/26226.72.2.65 to 226.72.2.126226.72.2.12762
11226.72.2.128/26226.72.2.129 to 226.72.2.190226.72.2.19162
12226.72.2.192/26226.72.2.193 to 226.72.2.254226.72.2.25562
13226.72.3.0/26226.72.3.1 to 226.72.3.62226.72.3.6362
14226.72.3.64/26226.72.3.65 to 226.72.3.126226.72.3.12762
15226.72.3.128/26226.72.3.129 to 226.72.3.190226.72.3.19162
16226.72.3.192/26226.72.3.193 to 226.72.3.254226.72.3.25562
17226.72.4.0/26226.72.4.1 to 226.72.4.62226.72.4.6362
18226.72.4.64/26226.72.4.65 to 226.72.4.126226.72.4.12762
19226.72.4.128/26226.72.4.129 to 226.72.4.190226.72.4.19162
20226.72.4.192/26226.72.4.193 to 226.72.4.254226.72.4.25562
21226.72.5.0/26226.72.5.1 to 226.72.5.62226.72.5.6362
22226.72.5.64/26226.72.5.65 to 226.72.5.126226.72.5.12762
23226.72.5.128/26226.72.5.129 to 226.72.5.190226.72.5.19162
24226.72.5.192/26226.72.5.193 to 226.72.5.254226.72.5.25562
25226.72.6.0/26226.72.6.1 to 226.72.6.62226.72.6.6362
26226.72.6.64/26226.72.6.65 to 226.72.6.126226.72.6.12762
27226.72.6.128/26226.72.6.129 to 226.72.6.190226.72.6.19162
28226.72.6.192/26226.72.6.193 to 226.72.6.254226.72.6.25562
29226.72.7.0/26226.72.7.1 to 226.72.7.62226.72.7.6362
30226.72.7.64/26226.72.7.65 to 226.72.7.126226.72.7.12762
31226.72.7.128/26226.72.7.129 to 226.72.7.190226.72.7.19162
32226.72.7.192/26226.72.7.193 to 226.72.7.254226.72.7.25562
33226.72.8.0/26226.72.8.1 to 226.72.8.62226.72.8.6362
34226.72.8.64/26226.72.8.65 to 226.72.8.126226.72.8.12762
35226.72.8.128/26226.72.8.129 to 226.72.8.190226.72.8.19162
36226.72.8.192/26226.72.8.193 to 226.72.8.254226.72.8.25562
37226.72.9.0/26226.72.9.1 to 226.72.9.62226.72.9.6362
38226.72.9.64/26226.72.9.65 to 226.72.9.126226.72.9.12762
39226.72.9.128/26226.72.9.129 to 226.72.9.190226.72.9.19162
40226.72.9.192/26226.72.9.193 to 226.72.9.254226.72.9.25562
41226.72.10.0/26226.72.10.1 to 226.72.10.62226.72.10.6362
42226.72.10.64/26226.72.10.65 to 226.72.10.126226.72.10.12762
43226.72.10.128/26226.72.10.129 to 226.72.10.190226.72.10.19162
44226.72.10.192/26226.72.10.193 to 226.72.10.254226.72.10.25562
45226.72.11.0/26226.72.11.1 to 226.72.11.62226.72.11.6362
46226.72.11.64/26226.72.11.65 to 226.72.11.126226.72.11.12762
47226.72.11.128/26226.72.11.129 to 226.72.11.190226.72.11.19162
48226.72.11.192/26226.72.11.193 to 226.72.11.254226.72.11.25562
49226.72.12.0/26226.72.12.1 to 226.72.12.62226.72.12.6362
50226.72.12.64/26226.72.12.65 to 226.72.12.126226.72.12.12762
51226.72.12.128/26226.72.12.129 to 226.72.12.190226.72.12.19162
52226.72.12.192/26226.72.12.193 to 226.72.12.254226.72.12.25562
53226.72.13.0/26226.72.13.1 to 226.72.13.62226.72.13.6362
54226.72.13.64/26226.72.13.65 to 226.72.13.126226.72.13.12762
55226.72.13.128/26226.72.13.129 to 226.72.13.190226.72.13.19162
56226.72.13.192/26226.72.13.193 to 226.72.13.254226.72.13.25562
57226.72.14.0/26226.72.14.1 to 226.72.14.62226.72.14.6362
58226.72.14.64/26226.72.14.65 to 226.72.14.126226.72.14.12762
59226.72.14.128/26226.72.14.129 to 226.72.14.190226.72.14.19162
60226.72.14.192/26226.72.14.193 to 226.72.14.254226.72.14.25562
61226.72.15.0/26226.72.15.1 to 226.72.15.62226.72.15.6362
62226.72.15.64/26226.72.15.65 to 226.72.15.126226.72.15.12762
63226.72.15.128/26226.72.15.129 to 226.72.15.190226.72.15.19162
64226.72.15.192/26226.72.15.193 to 226.72.15.254226.72.15.25562
65226.72.16.0/26226.72.16.1 to 226.72.16.62226.72.16.6362
66226.72.16.64/26226.72.16.65 to 226.72.16.126226.72.16.12762
67226.72.16.128/26226.72.16.129 to 226.72.16.190226.72.16.19162
68226.72.16.192/26226.72.16.193 to 226.72.16.254226.72.16.25562
69226.72.17.0/26226.72.17.1 to 226.72.17.62226.72.17.6362
70226.72.17.64/26226.72.17.65 to 226.72.17.126226.72.17.12762
71226.72.17.128/26226.72.17.129 to 226.72.17.190226.72.17.19162
72226.72.17.192/26226.72.17.193 to 226.72.17.254226.72.17.25562
73226.72.18.0/26226.72.18.1 to 226.72.18.62226.72.18.6362
74226.72.18.64/26226.72.18.65 to 226.72.18.126226.72.18.12762
75226.72.18.128/26226.72.18.129 to 226.72.18.190226.72.18.19162
76226.72.18.192/26226.72.18.193 to 226.72.18.254226.72.18.25562
77226.72.19.0/26226.72.19.1 to 226.72.19.62226.72.19.6362
78226.72.19.64/26226.72.19.65 to 226.72.19.126226.72.19.12762
79226.72.19.128/26226.72.19.129 to 226.72.19.190226.72.19.19162
80226.72.19.192/26226.72.19.193 to 226.72.19.254226.72.19.25562
81226.72.20.0/26226.72.20.1 to 226.72.20.62226.72.20.6362
82226.72.20.64/26226.72.20.65 to 226.72.20.126226.72.20.12762
83226.72.20.128/26226.72.20.129 to 226.72.20.190226.72.20.19162
84226.72.20.192/26226.72.20.193 to 226.72.20.254226.72.20.25562
85226.72.21.0/26226.72.21.1 to 226.72.21.62226.72.21.6362
86226.72.21.64/26226.72.21.65 to 226.72.21.126226.72.21.12762
87226.72.21.128/26226.72.21.129 to 226.72.21.190226.72.21.19162
88226.72.21.192/26226.72.21.193 to 226.72.21.254226.72.21.25562
89226.72.22.0/26226.72.22.1 to 226.72.22.62226.72.22.6362
90226.72.22.64/26226.72.22.65 to 226.72.22.126226.72.22.12762
91226.72.22.128/26226.72.22.129 to 226.72.22.190226.72.22.19162
92226.72.22.192/26226.72.22.193 to 226.72.22.254226.72.22.25562
93226.72.23.0/26226.72.23.1 to 226.72.23.62226.72.23.6362
94226.72.23.64/26226.72.23.65 to 226.72.23.126226.72.23.12762
95226.72.23.128/26226.72.23.129 to 226.72.23.190226.72.23.19162
96226.72.23.192/26226.72.23.193 to 226.72.23.254226.72.23.25562
97226.72.24.0/26226.72.24.1 to 226.72.24.62226.72.24.6362
98226.72.24.64/26226.72.24.65 to 226.72.24.126226.72.24.12762
99226.72.24.128/26226.72.24.129 to 226.72.24.190226.72.24.19162
100226.72.24.192/26226.72.24.193 to 226.72.24.254226.72.24.25562
101226.72.25.0/26226.72.25.1 to 226.72.25.62226.72.25.6362
102226.72.25.64/26226.72.25.65 to 226.72.25.126226.72.25.12762
103226.72.25.128/26226.72.25.129 to 226.72.25.190226.72.25.19162
104226.72.25.192/26226.72.25.193 to 226.72.25.254226.72.25.25562
105226.72.26.0/26226.72.26.1 to 226.72.26.62226.72.26.6362
106226.72.26.64/26226.72.26.65 to 226.72.26.126226.72.26.12762
107226.72.26.128/26226.72.26.129 to 226.72.26.190226.72.26.19162
108226.72.26.192/26226.72.26.193 to 226.72.26.254226.72.26.25562
109226.72.27.0/26226.72.27.1 to 226.72.27.62226.72.27.6362
110226.72.27.64/26226.72.27.65 to 226.72.27.126226.72.27.12762
111226.72.27.128/26226.72.27.129 to 226.72.27.190226.72.27.19162
112226.72.27.192/26226.72.27.193 to 226.72.27.254226.72.27.25562
113226.72.28.0/26226.72.28.1 to 226.72.28.62226.72.28.6362
114226.72.28.64/26226.72.28.65 to 226.72.28.126226.72.28.12762
115226.72.28.128/26226.72.28.129 to 226.72.28.190226.72.28.19162
116226.72.28.192/26226.72.28.193 to 226.72.28.254226.72.28.25562
117226.72.29.0/26226.72.29.1 to 226.72.29.62226.72.29.6362
118226.72.29.64/26226.72.29.65 to 226.72.29.126226.72.29.12762
119226.72.29.128/26226.72.29.129 to 226.72.29.190226.72.29.19162
120226.72.29.192/26226.72.29.193 to 226.72.29.254226.72.29.25562
121226.72.30.0/26226.72.30.1 to 226.72.30.62226.72.30.6362
122226.72.30.64/26226.72.30.65 to 226.72.30.126226.72.30.12762
123226.72.30.128/26226.72.30.129 to 226.72.30.190226.72.30.19162
124226.72.30.192/26226.72.30.193 to 226.72.30.254226.72.30.25562
125226.72.31.0/26226.72.31.1 to 226.72.31.62226.72.31.6362
126226.72.31.64/26226.72.31.65 to 226.72.31.126226.72.31.12762
127226.72.31.128/26226.72.31.129 to 226.72.31.190226.72.31.19162
128226.72.31.192/26226.72.31.193 to 226.72.31.254226.72.31.25562
129226.72.32.0/26226.72.32.1 to 226.72.32.62226.72.32.6362
130226.72.32.64/26226.72.32.65 to 226.72.32.126226.72.32.12762
131226.72.32.128/26226.72.32.129 to 226.72.32.190226.72.32.19162
132226.72.32.192/26226.72.32.193 to 226.72.32.254226.72.32.25562
133226.72.33.0/26226.72.33.1 to 226.72.33.62226.72.33.6362
134226.72.33.64/26226.72.33.65 to 226.72.33.126226.72.33.12762
135226.72.33.128/26226.72.33.129 to 226.72.33.190226.72.33.19162
136226.72.33.192/26226.72.33.193 to 226.72.33.254226.72.33.25562
137226.72.34.0/26226.72.34.1 to 226.72.34.62226.72.34.6362
138226.72.34.64/26226.72.34.65 to 226.72.34.126226.72.34.12762
139226.72.34.128/26226.72.34.129 to 226.72.34.190226.72.34.19162
140226.72.34.192/26226.72.34.193 to 226.72.34.254226.72.34.25562
141226.72.35.0/26226.72.35.1 to 226.72.35.62226.72.35.6362
142226.72.35.64/26226.72.35.65 to 226.72.35.126226.72.35.12762
143226.72.35.128/26226.72.35.129 to 226.72.35.190226.72.35.19162
144226.72.35.192/26226.72.35.193 to 226.72.35.254226.72.35.25562
145226.72.36.0/26226.72.36.1 to 226.72.36.62226.72.36.6362
146226.72.36.64/26226.72.36.65 to 226.72.36.126226.72.36.12762
147226.72.36.128/26226.72.36.129 to 226.72.36.190226.72.36.19162
148226.72.36.192/26226.72.36.193 to 226.72.36.254226.72.36.25562
149226.72.37.0/26226.72.37.1 to 226.72.37.62226.72.37.6362
150226.72.37.64/26226.72.37.65 to 226.72.37.126226.72.37.12762
151226.72.37.128/26226.72.37.129 to 226.72.37.190226.72.37.19162
152226.72.37.192/26226.72.37.193 to 226.72.37.254226.72.37.25562
153226.72.38.0/26226.72.38.1 to 226.72.38.62226.72.38.6362
154226.72.38.64/26226.72.38.65 to 226.72.38.126226.72.38.12762
155226.72.38.128/26226.72.38.129 to 226.72.38.190226.72.38.19162
156226.72.38.192/26226.72.38.193 to 226.72.38.254226.72.38.25562
157226.72.39.0/26226.72.39.1 to 226.72.39.62226.72.39.6362
158226.72.39.64/26226.72.39.65 to 226.72.39.126226.72.39.12762
159226.72.39.128/26226.72.39.129 to 226.72.39.190226.72.39.19162
160226.72.39.192/26226.72.39.193 to 226.72.39.254226.72.39.25562
161226.72.40.0/26226.72.40.1 to 226.72.40.62226.72.40.6362
162226.72.40.64/26226.72.40.65 to 226.72.40.126226.72.40.12762
163226.72.40.128/26226.72.40.129 to 226.72.40.190226.72.40.19162
164226.72.40.192/26226.72.40.193 to 226.72.40.254226.72.40.25562
165226.72.41.0/26226.72.41.1 to 226.72.41.62226.72.41.6362
166226.72.41.64/26226.72.41.65 to 226.72.41.126226.72.41.12762
167226.72.41.128/26226.72.41.129 to 226.72.41.190226.72.41.19162
168226.72.41.192/26226.72.41.193 to 226.72.41.254226.72.41.25562
169226.72.42.0/26226.72.42.1 to 226.72.42.62226.72.42.6362
170226.72.42.64/26226.72.42.65 to 226.72.42.126226.72.42.12762
171226.72.42.128/26226.72.42.129 to 226.72.42.190226.72.42.19162
172226.72.42.192/26226.72.42.193 to 226.72.42.254226.72.42.25562
173226.72.43.0/26226.72.43.1 to 226.72.43.62226.72.43.6362
174226.72.43.64/26226.72.43.65 to 226.72.43.126226.72.43.12762
175226.72.43.128/26226.72.43.129 to 226.72.43.190226.72.43.19162
176226.72.43.192/26226.72.43.193 to 226.72.43.254226.72.43.25562
177226.72.44.0/26226.72.44.1 to 226.72.44.62226.72.44.6362
178226.72.44.64/26226.72.44.65 to 226.72.44.126226.72.44.12762
179226.72.44.128/26226.72.44.129 to 226.72.44.190226.72.44.19162
180226.72.44.192/26226.72.44.193 to 226.72.44.254226.72.44.25562
181226.72.45.0/26226.72.45.1 to 226.72.45.62226.72.45.6362
182226.72.45.64/26226.72.45.65 to 226.72.45.126226.72.45.12762
183226.72.45.128/26226.72.45.129 to 226.72.45.190226.72.45.19162
184226.72.45.192/26226.72.45.193 to 226.72.45.254226.72.45.25562
185226.72.46.0/26226.72.46.1 to 226.72.46.62226.72.46.6362
186226.72.46.64/26226.72.46.65 to 226.72.46.126226.72.46.12762
187226.72.46.128/26226.72.46.129 to 226.72.46.190226.72.46.19162
188226.72.46.192/26226.72.46.193 to 226.72.46.254226.72.46.25562
189226.72.47.0/26226.72.47.1 to 226.72.47.62226.72.47.6362
190226.72.47.64/26226.72.47.65 to 226.72.47.126226.72.47.12762
191226.72.47.128/26226.72.47.129 to 226.72.47.190226.72.47.19162
192226.72.47.192/26226.72.47.193 to 226.72.47.254226.72.47.25562
193226.72.48.0/26226.72.48.1 to 226.72.48.62226.72.48.6362
194226.72.48.64/26226.72.48.65 to 226.72.48.126226.72.48.12762
195226.72.48.128/26226.72.48.129 to 226.72.48.190226.72.48.19162
196226.72.48.192/26226.72.48.193 to 226.72.48.254226.72.48.25562
197226.72.49.0/26226.72.49.1 to 226.72.49.62226.72.49.6362
198226.72.49.64/26226.72.49.65 to 226.72.49.126226.72.49.12762
199226.72.49.128/26226.72.49.129 to 226.72.49.190226.72.49.19162
200226.72.49.192/26226.72.49.193 to 226.72.49.254226.72.49.25562
201226.72.50.0/26226.72.50.1 to 226.72.50.62226.72.50.6362
202226.72.50.64/26226.72.50.65 to 226.72.50.126226.72.50.12762
203226.72.50.128/26226.72.50.129 to 226.72.50.190226.72.50.19162
204226.72.50.192/26226.72.50.193 to 226.72.50.254226.72.50.25562
205226.72.51.0/26226.72.51.1 to 226.72.51.62226.72.51.6362
206226.72.51.64/26226.72.51.65 to 226.72.51.126226.72.51.12762
207226.72.51.128/26226.72.51.129 to 226.72.51.190226.72.51.19162
208226.72.51.192/26226.72.51.193 to 226.72.51.254226.72.51.25562
209226.72.52.0/26226.72.52.1 to 226.72.52.62226.72.52.6362
210226.72.52.64/26226.72.52.65 to 226.72.52.126226.72.52.12762
211226.72.52.128/26226.72.52.129 to 226.72.52.190226.72.52.19162
212226.72.52.192/26226.72.52.193 to 226.72.52.254226.72.52.25562
213226.72.53.0/26226.72.53.1 to 226.72.53.62226.72.53.6362
214226.72.53.64/26226.72.53.65 to 226.72.53.126226.72.53.12762
215226.72.53.128/26226.72.53.129 to 226.72.53.190226.72.53.19162
216226.72.53.192/26226.72.53.193 to 226.72.53.254226.72.53.25562
217226.72.54.0/26226.72.54.1 to 226.72.54.62226.72.54.6362
218226.72.54.64/26226.72.54.65 to 226.72.54.126226.72.54.12762
219226.72.54.128/26226.72.54.129 to 226.72.54.190226.72.54.19162
220226.72.54.192/26226.72.54.193 to 226.72.54.254226.72.54.25562
221226.72.55.0/26226.72.55.1 to 226.72.55.62226.72.55.6362
222226.72.55.64/26226.72.55.65 to 226.72.55.126226.72.55.12762
223226.72.55.128/26226.72.55.129 to 226.72.55.190226.72.55.19162
224226.72.55.192/26226.72.55.193 to 226.72.55.254226.72.55.25562
225226.72.56.0/26226.72.56.1 to 226.72.56.62226.72.56.6362
226226.72.56.64/26226.72.56.65 to 226.72.56.126226.72.56.12762
227226.72.56.128/26226.72.56.129 to 226.72.56.190226.72.56.19162
228226.72.56.192/26226.72.56.193 to 226.72.56.254226.72.56.25562
229226.72.57.0/26226.72.57.1 to 226.72.57.62226.72.57.6362
230226.72.57.64/26226.72.57.65 to 226.72.57.126226.72.57.12762
231226.72.57.128/26226.72.57.129 to 226.72.57.190226.72.57.19162
232226.72.57.192/26226.72.57.193 to 226.72.57.254226.72.57.25562
233226.72.58.0/26226.72.58.1 to 226.72.58.62226.72.58.6362
234226.72.58.64/26226.72.58.65 to 226.72.58.126226.72.58.12762
235226.72.58.128/26226.72.58.129 to 226.72.58.190226.72.58.19162
236226.72.58.192/26226.72.58.193 to 226.72.58.254226.72.58.25562
237226.72.59.0/26226.72.59.1 to 226.72.59.62226.72.59.6362
238226.72.59.64/26226.72.59.65 to 226.72.59.126226.72.59.12762
239226.72.59.128/26226.72.59.129 to 226.72.59.190226.72.59.19162
240226.72.59.192/26226.72.59.193 to 226.72.59.254226.72.59.25562
241226.72.60.0/26226.72.60.1 to 226.72.60.62226.72.60.6362
242226.72.60.64/26226.72.60.65 to 226.72.60.126226.72.60.12762
243226.72.60.128/26226.72.60.129 to 226.72.60.190226.72.60.19162
244226.72.60.192/26226.72.60.193 to 226.72.60.254226.72.60.25562
245226.72.61.0/26226.72.61.1 to 226.72.61.62226.72.61.6362
246226.72.61.64/26226.72.61.65 to 226.72.61.126226.72.61.12762
247226.72.61.128/26226.72.61.129 to 226.72.61.190226.72.61.19162
248226.72.61.192/26226.72.61.193 to 226.72.61.254226.72.61.25562
249226.72.62.0/26226.72.62.1 to 226.72.62.62226.72.62.6362
250226.72.62.64/26226.72.62.65 to 226.72.62.126226.72.62.12762
251226.72.62.128/26226.72.62.129 to 226.72.62.190226.72.62.19162
252226.72.62.192/26226.72.62.193 to 226.72.62.254226.72.62.25562
253226.72.63.0/26226.72.63.1 to 226.72.63.62226.72.63.6362
254226.72.63.64/26226.72.63.65 to 226.72.63.126226.72.63.12762
255226.72.63.128/26226.72.63.129 to 226.72.63.190226.72.63.19162
256226.72.63.192/26226.72.63.193 to 226.72.63.254226.72.63.25562

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.