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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.

Network226.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
226.0.0.0
Broadcast address
226.255.255.255
First usable
226.0.0.1
Last usable
226.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E2000000 · Integer 3791650816 to 3808428031
Reverse DNS zone
226.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100010..00000000.00000000.00000000226.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network11100010..00000000.00000000.00000000226.0.0.0
Broadcast11100010..11111111.11111111.11111111226.255.255.255
Split into smaller subnets/18
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

226.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1226.0.0.0/18226.0.0.1 to 226.0.63.254226.0.63.25516,382
2226.0.64.0/18226.0.64.1 to 226.0.127.254226.0.127.25516,382
3226.0.128.0/18226.0.128.1 to 226.0.191.254226.0.191.25516,382
4226.0.192.0/18226.0.192.1 to 226.0.255.254226.0.255.25516,382
5226.1.0.0/18226.1.0.1 to 226.1.63.254226.1.63.25516,382
6226.1.64.0/18226.1.64.1 to 226.1.127.254226.1.127.25516,382
7226.1.128.0/18226.1.128.1 to 226.1.191.254226.1.191.25516,382
8226.1.192.0/18226.1.192.1 to 226.1.255.254226.1.255.25516,382
9226.2.0.0/18226.2.0.1 to 226.2.63.254226.2.63.25516,382
10226.2.64.0/18226.2.64.1 to 226.2.127.254226.2.127.25516,382
11226.2.128.0/18226.2.128.1 to 226.2.191.254226.2.191.25516,382
12226.2.192.0/18226.2.192.1 to 226.2.255.254226.2.255.25516,382
13226.3.0.0/18226.3.0.1 to 226.3.63.254226.3.63.25516,382
14226.3.64.0/18226.3.64.1 to 226.3.127.254226.3.127.25516,382
15226.3.128.0/18226.3.128.1 to 226.3.191.254226.3.191.25516,382
16226.3.192.0/18226.3.192.1 to 226.3.255.254226.3.255.25516,382
17226.4.0.0/18226.4.0.1 to 226.4.63.254226.4.63.25516,382
18226.4.64.0/18226.4.64.1 to 226.4.127.254226.4.127.25516,382
19226.4.128.0/18226.4.128.1 to 226.4.191.254226.4.191.25516,382
20226.4.192.0/18226.4.192.1 to 226.4.255.254226.4.255.25516,382
21226.5.0.0/18226.5.0.1 to 226.5.63.254226.5.63.25516,382
22226.5.64.0/18226.5.64.1 to 226.5.127.254226.5.127.25516,382
23226.5.128.0/18226.5.128.1 to 226.5.191.254226.5.191.25516,382
24226.5.192.0/18226.5.192.1 to 226.5.255.254226.5.255.25516,382
25226.6.0.0/18226.6.0.1 to 226.6.63.254226.6.63.25516,382
26226.6.64.0/18226.6.64.1 to 226.6.127.254226.6.127.25516,382
27226.6.128.0/18226.6.128.1 to 226.6.191.254226.6.191.25516,382
28226.6.192.0/18226.6.192.1 to 226.6.255.254226.6.255.25516,382
29226.7.0.0/18226.7.0.1 to 226.7.63.254226.7.63.25516,382
30226.7.64.0/18226.7.64.1 to 226.7.127.254226.7.127.25516,382
31226.7.128.0/18226.7.128.1 to 226.7.191.254226.7.191.25516,382
32226.7.192.0/18226.7.192.1 to 226.7.255.254226.7.255.25516,382
33226.8.0.0/18226.8.0.1 to 226.8.63.254226.8.63.25516,382
34226.8.64.0/18226.8.64.1 to 226.8.127.254226.8.127.25516,382
35226.8.128.0/18226.8.128.1 to 226.8.191.254226.8.191.25516,382
36226.8.192.0/18226.8.192.1 to 226.8.255.254226.8.255.25516,382
37226.9.0.0/18226.9.0.1 to 226.9.63.254226.9.63.25516,382
38226.9.64.0/18226.9.64.1 to 226.9.127.254226.9.127.25516,382
39226.9.128.0/18226.9.128.1 to 226.9.191.254226.9.191.25516,382
40226.9.192.0/18226.9.192.1 to 226.9.255.254226.9.255.25516,382
41226.10.0.0/18226.10.0.1 to 226.10.63.254226.10.63.25516,382
42226.10.64.0/18226.10.64.1 to 226.10.127.254226.10.127.25516,382
43226.10.128.0/18226.10.128.1 to 226.10.191.254226.10.191.25516,382
44226.10.192.0/18226.10.192.1 to 226.10.255.254226.10.255.25516,382
45226.11.0.0/18226.11.0.1 to 226.11.63.254226.11.63.25516,382
46226.11.64.0/18226.11.64.1 to 226.11.127.254226.11.127.25516,382
47226.11.128.0/18226.11.128.1 to 226.11.191.254226.11.191.25516,382
48226.11.192.0/18226.11.192.1 to 226.11.255.254226.11.255.25516,382
49226.12.0.0/18226.12.0.1 to 226.12.63.254226.12.63.25516,382
50226.12.64.0/18226.12.64.1 to 226.12.127.254226.12.127.25516,382
51226.12.128.0/18226.12.128.1 to 226.12.191.254226.12.191.25516,382
52226.12.192.0/18226.12.192.1 to 226.12.255.254226.12.255.25516,382
53226.13.0.0/18226.13.0.1 to 226.13.63.254226.13.63.25516,382
54226.13.64.0/18226.13.64.1 to 226.13.127.254226.13.127.25516,382
55226.13.128.0/18226.13.128.1 to 226.13.191.254226.13.191.25516,382
56226.13.192.0/18226.13.192.1 to 226.13.255.254226.13.255.25516,382
57226.14.0.0/18226.14.0.1 to 226.14.63.254226.14.63.25516,382
58226.14.64.0/18226.14.64.1 to 226.14.127.254226.14.127.25516,382
59226.14.128.0/18226.14.128.1 to 226.14.191.254226.14.191.25516,382
60226.14.192.0/18226.14.192.1 to 226.14.255.254226.14.255.25516,382
61226.15.0.0/18226.15.0.1 to 226.15.63.254226.15.63.25516,382
62226.15.64.0/18226.15.64.1 to 226.15.127.254226.15.127.25516,382
63226.15.128.0/18226.15.128.1 to 226.15.191.254226.15.191.25516,382
64226.15.192.0/18226.15.192.1 to 226.15.255.254226.15.255.25516,382
65226.16.0.0/18226.16.0.1 to 226.16.63.254226.16.63.25516,382
66226.16.64.0/18226.16.64.1 to 226.16.127.254226.16.127.25516,382
67226.16.128.0/18226.16.128.1 to 226.16.191.254226.16.191.25516,382
68226.16.192.0/18226.16.192.1 to 226.16.255.254226.16.255.25516,382
69226.17.0.0/18226.17.0.1 to 226.17.63.254226.17.63.25516,382
70226.17.64.0/18226.17.64.1 to 226.17.127.254226.17.127.25516,382
71226.17.128.0/18226.17.128.1 to 226.17.191.254226.17.191.25516,382
72226.17.192.0/18226.17.192.1 to 226.17.255.254226.17.255.25516,382
73226.18.0.0/18226.18.0.1 to 226.18.63.254226.18.63.25516,382
74226.18.64.0/18226.18.64.1 to 226.18.127.254226.18.127.25516,382
75226.18.128.0/18226.18.128.1 to 226.18.191.254226.18.191.25516,382
76226.18.192.0/18226.18.192.1 to 226.18.255.254226.18.255.25516,382
77226.19.0.0/18226.19.0.1 to 226.19.63.254226.19.63.25516,382
78226.19.64.0/18226.19.64.1 to 226.19.127.254226.19.127.25516,382
79226.19.128.0/18226.19.128.1 to 226.19.191.254226.19.191.25516,382
80226.19.192.0/18226.19.192.1 to 226.19.255.254226.19.255.25516,382
81226.20.0.0/18226.20.0.1 to 226.20.63.254226.20.63.25516,382
82226.20.64.0/18226.20.64.1 to 226.20.127.254226.20.127.25516,382
83226.20.128.0/18226.20.128.1 to 226.20.191.254226.20.191.25516,382
84226.20.192.0/18226.20.192.1 to 226.20.255.254226.20.255.25516,382
85226.21.0.0/18226.21.0.1 to 226.21.63.254226.21.63.25516,382
86226.21.64.0/18226.21.64.1 to 226.21.127.254226.21.127.25516,382
87226.21.128.0/18226.21.128.1 to 226.21.191.254226.21.191.25516,382
88226.21.192.0/18226.21.192.1 to 226.21.255.254226.21.255.25516,382
89226.22.0.0/18226.22.0.1 to 226.22.63.254226.22.63.25516,382
90226.22.64.0/18226.22.64.1 to 226.22.127.254226.22.127.25516,382
91226.22.128.0/18226.22.128.1 to 226.22.191.254226.22.191.25516,382
92226.22.192.0/18226.22.192.1 to 226.22.255.254226.22.255.25516,382
93226.23.0.0/18226.23.0.1 to 226.23.63.254226.23.63.25516,382
94226.23.64.0/18226.23.64.1 to 226.23.127.254226.23.127.25516,382
95226.23.128.0/18226.23.128.1 to 226.23.191.254226.23.191.25516,382
96226.23.192.0/18226.23.192.1 to 226.23.255.254226.23.255.25516,382
97226.24.0.0/18226.24.0.1 to 226.24.63.254226.24.63.25516,382
98226.24.64.0/18226.24.64.1 to 226.24.127.254226.24.127.25516,382
99226.24.128.0/18226.24.128.1 to 226.24.191.254226.24.191.25516,382
100226.24.192.0/18226.24.192.1 to 226.24.255.254226.24.255.25516,382
101226.25.0.0/18226.25.0.1 to 226.25.63.254226.25.63.25516,382
102226.25.64.0/18226.25.64.1 to 226.25.127.254226.25.127.25516,382
103226.25.128.0/18226.25.128.1 to 226.25.191.254226.25.191.25516,382
104226.25.192.0/18226.25.192.1 to 226.25.255.254226.25.255.25516,382
105226.26.0.0/18226.26.0.1 to 226.26.63.254226.26.63.25516,382
106226.26.64.0/18226.26.64.1 to 226.26.127.254226.26.127.25516,382
107226.26.128.0/18226.26.128.1 to 226.26.191.254226.26.191.25516,382
108226.26.192.0/18226.26.192.1 to 226.26.255.254226.26.255.25516,382
109226.27.0.0/18226.27.0.1 to 226.27.63.254226.27.63.25516,382
110226.27.64.0/18226.27.64.1 to 226.27.127.254226.27.127.25516,382
111226.27.128.0/18226.27.128.1 to 226.27.191.254226.27.191.25516,382
112226.27.192.0/18226.27.192.1 to 226.27.255.254226.27.255.25516,382
113226.28.0.0/18226.28.0.1 to 226.28.63.254226.28.63.25516,382
114226.28.64.0/18226.28.64.1 to 226.28.127.254226.28.127.25516,382
115226.28.128.0/18226.28.128.1 to 226.28.191.254226.28.191.25516,382
116226.28.192.0/18226.28.192.1 to 226.28.255.254226.28.255.25516,382
117226.29.0.0/18226.29.0.1 to 226.29.63.254226.29.63.25516,382
118226.29.64.0/18226.29.64.1 to 226.29.127.254226.29.127.25516,382
119226.29.128.0/18226.29.128.1 to 226.29.191.254226.29.191.25516,382
120226.29.192.0/18226.29.192.1 to 226.29.255.254226.29.255.25516,382
121226.30.0.0/18226.30.0.1 to 226.30.63.254226.30.63.25516,382
122226.30.64.0/18226.30.64.1 to 226.30.127.254226.30.127.25516,382
123226.30.128.0/18226.30.128.1 to 226.30.191.254226.30.191.25516,382
124226.30.192.0/18226.30.192.1 to 226.30.255.254226.30.255.25516,382
125226.31.0.0/18226.31.0.1 to 226.31.63.254226.31.63.25516,382
126226.31.64.0/18226.31.64.1 to 226.31.127.254226.31.127.25516,382
127226.31.128.0/18226.31.128.1 to 226.31.191.254226.31.191.25516,382
128226.31.192.0/18226.31.192.1 to 226.31.255.254226.31.255.25516,382
129226.32.0.0/18226.32.0.1 to 226.32.63.254226.32.63.25516,382
130226.32.64.0/18226.32.64.1 to 226.32.127.254226.32.127.25516,382
131226.32.128.0/18226.32.128.1 to 226.32.191.254226.32.191.25516,382
132226.32.192.0/18226.32.192.1 to 226.32.255.254226.32.255.25516,382
133226.33.0.0/18226.33.0.1 to 226.33.63.254226.33.63.25516,382
134226.33.64.0/18226.33.64.1 to 226.33.127.254226.33.127.25516,382
135226.33.128.0/18226.33.128.1 to 226.33.191.254226.33.191.25516,382
136226.33.192.0/18226.33.192.1 to 226.33.255.254226.33.255.25516,382
137226.34.0.0/18226.34.0.1 to 226.34.63.254226.34.63.25516,382
138226.34.64.0/18226.34.64.1 to 226.34.127.254226.34.127.25516,382
139226.34.128.0/18226.34.128.1 to 226.34.191.254226.34.191.25516,382
140226.34.192.0/18226.34.192.1 to 226.34.255.254226.34.255.25516,382
141226.35.0.0/18226.35.0.1 to 226.35.63.254226.35.63.25516,382
142226.35.64.0/18226.35.64.1 to 226.35.127.254226.35.127.25516,382
143226.35.128.0/18226.35.128.1 to 226.35.191.254226.35.191.25516,382
144226.35.192.0/18226.35.192.1 to 226.35.255.254226.35.255.25516,382
145226.36.0.0/18226.36.0.1 to 226.36.63.254226.36.63.25516,382
146226.36.64.0/18226.36.64.1 to 226.36.127.254226.36.127.25516,382
147226.36.128.0/18226.36.128.1 to 226.36.191.254226.36.191.25516,382
148226.36.192.0/18226.36.192.1 to 226.36.255.254226.36.255.25516,382
149226.37.0.0/18226.37.0.1 to 226.37.63.254226.37.63.25516,382
150226.37.64.0/18226.37.64.1 to 226.37.127.254226.37.127.25516,382
151226.37.128.0/18226.37.128.1 to 226.37.191.254226.37.191.25516,382
152226.37.192.0/18226.37.192.1 to 226.37.255.254226.37.255.25516,382
153226.38.0.0/18226.38.0.1 to 226.38.63.254226.38.63.25516,382
154226.38.64.0/18226.38.64.1 to 226.38.127.254226.38.127.25516,382
155226.38.128.0/18226.38.128.1 to 226.38.191.254226.38.191.25516,382
156226.38.192.0/18226.38.192.1 to 226.38.255.254226.38.255.25516,382
157226.39.0.0/18226.39.0.1 to 226.39.63.254226.39.63.25516,382
158226.39.64.0/18226.39.64.1 to 226.39.127.254226.39.127.25516,382
159226.39.128.0/18226.39.128.1 to 226.39.191.254226.39.191.25516,382
160226.39.192.0/18226.39.192.1 to 226.39.255.254226.39.255.25516,382
161226.40.0.0/18226.40.0.1 to 226.40.63.254226.40.63.25516,382
162226.40.64.0/18226.40.64.1 to 226.40.127.254226.40.127.25516,382
163226.40.128.0/18226.40.128.1 to 226.40.191.254226.40.191.25516,382
164226.40.192.0/18226.40.192.1 to 226.40.255.254226.40.255.25516,382
165226.41.0.0/18226.41.0.1 to 226.41.63.254226.41.63.25516,382
166226.41.64.0/18226.41.64.1 to 226.41.127.254226.41.127.25516,382
167226.41.128.0/18226.41.128.1 to 226.41.191.254226.41.191.25516,382
168226.41.192.0/18226.41.192.1 to 226.41.255.254226.41.255.25516,382
169226.42.0.0/18226.42.0.1 to 226.42.63.254226.42.63.25516,382
170226.42.64.0/18226.42.64.1 to 226.42.127.254226.42.127.25516,382
171226.42.128.0/18226.42.128.1 to 226.42.191.254226.42.191.25516,382
172226.42.192.0/18226.42.192.1 to 226.42.255.254226.42.255.25516,382
173226.43.0.0/18226.43.0.1 to 226.43.63.254226.43.63.25516,382
174226.43.64.0/18226.43.64.1 to 226.43.127.254226.43.127.25516,382
175226.43.128.0/18226.43.128.1 to 226.43.191.254226.43.191.25516,382
176226.43.192.0/18226.43.192.1 to 226.43.255.254226.43.255.25516,382
177226.44.0.0/18226.44.0.1 to 226.44.63.254226.44.63.25516,382
178226.44.64.0/18226.44.64.1 to 226.44.127.254226.44.127.25516,382
179226.44.128.0/18226.44.128.1 to 226.44.191.254226.44.191.25516,382
180226.44.192.0/18226.44.192.1 to 226.44.255.254226.44.255.25516,382
181226.45.0.0/18226.45.0.1 to 226.45.63.254226.45.63.25516,382
182226.45.64.0/18226.45.64.1 to 226.45.127.254226.45.127.25516,382
183226.45.128.0/18226.45.128.1 to 226.45.191.254226.45.191.25516,382
184226.45.192.0/18226.45.192.1 to 226.45.255.254226.45.255.25516,382
185226.46.0.0/18226.46.0.1 to 226.46.63.254226.46.63.25516,382
186226.46.64.0/18226.46.64.1 to 226.46.127.254226.46.127.25516,382
187226.46.128.0/18226.46.128.1 to 226.46.191.254226.46.191.25516,382
188226.46.192.0/18226.46.192.1 to 226.46.255.254226.46.255.25516,382
189226.47.0.0/18226.47.0.1 to 226.47.63.254226.47.63.25516,382
190226.47.64.0/18226.47.64.1 to 226.47.127.254226.47.127.25516,382
191226.47.128.0/18226.47.128.1 to 226.47.191.254226.47.191.25516,382
192226.47.192.0/18226.47.192.1 to 226.47.255.254226.47.255.25516,382
193226.48.0.0/18226.48.0.1 to 226.48.63.254226.48.63.25516,382
194226.48.64.0/18226.48.64.1 to 226.48.127.254226.48.127.25516,382
195226.48.128.0/18226.48.128.1 to 226.48.191.254226.48.191.25516,382
196226.48.192.0/18226.48.192.1 to 226.48.255.254226.48.255.25516,382
197226.49.0.0/18226.49.0.1 to 226.49.63.254226.49.63.25516,382
198226.49.64.0/18226.49.64.1 to 226.49.127.254226.49.127.25516,382
199226.49.128.0/18226.49.128.1 to 226.49.191.254226.49.191.25516,382
200226.49.192.0/18226.49.192.1 to 226.49.255.254226.49.255.25516,382
201226.50.0.0/18226.50.0.1 to 226.50.63.254226.50.63.25516,382
202226.50.64.0/18226.50.64.1 to 226.50.127.254226.50.127.25516,382
203226.50.128.0/18226.50.128.1 to 226.50.191.254226.50.191.25516,382
204226.50.192.0/18226.50.192.1 to 226.50.255.254226.50.255.25516,382
205226.51.0.0/18226.51.0.1 to 226.51.63.254226.51.63.25516,382
206226.51.64.0/18226.51.64.1 to 226.51.127.254226.51.127.25516,382
207226.51.128.0/18226.51.128.1 to 226.51.191.254226.51.191.25516,382
208226.51.192.0/18226.51.192.1 to 226.51.255.254226.51.255.25516,382
209226.52.0.0/18226.52.0.1 to 226.52.63.254226.52.63.25516,382
210226.52.64.0/18226.52.64.1 to 226.52.127.254226.52.127.25516,382
211226.52.128.0/18226.52.128.1 to 226.52.191.254226.52.191.25516,382
212226.52.192.0/18226.52.192.1 to 226.52.255.254226.52.255.25516,382
213226.53.0.0/18226.53.0.1 to 226.53.63.254226.53.63.25516,382
214226.53.64.0/18226.53.64.1 to 226.53.127.254226.53.127.25516,382
215226.53.128.0/18226.53.128.1 to 226.53.191.254226.53.191.25516,382
216226.53.192.0/18226.53.192.1 to 226.53.255.254226.53.255.25516,382
217226.54.0.0/18226.54.0.1 to 226.54.63.254226.54.63.25516,382
218226.54.64.0/18226.54.64.1 to 226.54.127.254226.54.127.25516,382
219226.54.128.0/18226.54.128.1 to 226.54.191.254226.54.191.25516,382
220226.54.192.0/18226.54.192.1 to 226.54.255.254226.54.255.25516,382
221226.55.0.0/18226.55.0.1 to 226.55.63.254226.55.63.25516,382
222226.55.64.0/18226.55.64.1 to 226.55.127.254226.55.127.25516,382
223226.55.128.0/18226.55.128.1 to 226.55.191.254226.55.191.25516,382
224226.55.192.0/18226.55.192.1 to 226.55.255.254226.55.255.25516,382
225226.56.0.0/18226.56.0.1 to 226.56.63.254226.56.63.25516,382
226226.56.64.0/18226.56.64.1 to 226.56.127.254226.56.127.25516,382
227226.56.128.0/18226.56.128.1 to 226.56.191.254226.56.191.25516,382
228226.56.192.0/18226.56.192.1 to 226.56.255.254226.56.255.25516,382
229226.57.0.0/18226.57.0.1 to 226.57.63.254226.57.63.25516,382
230226.57.64.0/18226.57.64.1 to 226.57.127.254226.57.127.25516,382
231226.57.128.0/18226.57.128.1 to 226.57.191.254226.57.191.25516,382
232226.57.192.0/18226.57.192.1 to 226.57.255.254226.57.255.25516,382
233226.58.0.0/18226.58.0.1 to 226.58.63.254226.58.63.25516,382
234226.58.64.0/18226.58.64.1 to 226.58.127.254226.58.127.25516,382
235226.58.128.0/18226.58.128.1 to 226.58.191.254226.58.191.25516,382
236226.58.192.0/18226.58.192.1 to 226.58.255.254226.58.255.25516,382
237226.59.0.0/18226.59.0.1 to 226.59.63.254226.59.63.25516,382
238226.59.64.0/18226.59.64.1 to 226.59.127.254226.59.127.25516,382
239226.59.128.0/18226.59.128.1 to 226.59.191.254226.59.191.25516,382
240226.59.192.0/18226.59.192.1 to 226.59.255.254226.59.255.25516,382
241226.60.0.0/18226.60.0.1 to 226.60.63.254226.60.63.25516,382
242226.60.64.0/18226.60.64.1 to 226.60.127.254226.60.127.25516,382
243226.60.128.0/18226.60.128.1 to 226.60.191.254226.60.191.25516,382
244226.60.192.0/18226.60.192.1 to 226.60.255.254226.60.255.25516,382
245226.61.0.0/18226.61.0.1 to 226.61.63.254226.61.63.25516,382
246226.61.64.0/18226.61.64.1 to 226.61.127.254226.61.127.25516,382
247226.61.128.0/18226.61.128.1 to 226.61.191.254226.61.191.25516,382
248226.61.192.0/18226.61.192.1 to 226.61.255.254226.61.255.25516,382
249226.62.0.0/18226.62.0.1 to 226.62.63.254226.62.63.25516,382
250226.62.64.0/18226.62.64.1 to 226.62.127.254226.62.127.25516,382
251226.62.128.0/18226.62.128.1 to 226.62.191.254226.62.191.25516,382
252226.62.192.0/18226.62.192.1 to 226.62.255.254226.62.255.25516,382
253226.63.0.0/18226.63.0.1 to 226.63.63.254226.63.63.25516,382
254226.63.64.0/18226.63.64.1 to 226.63.127.254226.63.127.25516,382
255226.63.128.0/18226.63.128.1 to 226.63.191.254226.63.191.25516,382
256226.63.192.0/18226.63.192.1 to 226.63.255.254226.63.255.25516,382

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.