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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.

Network226.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
226.0.0.0
Broadcast address
227.255.255.255
First usable
226.0.0.1
Last usable
227.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
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 3825205247
Reverse DNS zones
226.in-addr.arpa
227.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100010.00000000.00000000.00000000226.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network11100010.00000000.00000000.00000000226.0.0.0
Broadcast11100011.11111111.11111111.11111111227.255.255.255
Split into smaller subnets/17
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

226.0.0.0/7 makes 1,024 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1226.0.0.0/17226.0.0.1 to 226.0.127.254226.0.127.25532,766
2226.0.128.0/17226.0.128.1 to 226.0.255.254226.0.255.25532,766
3226.1.0.0/17226.1.0.1 to 226.1.127.254226.1.127.25532,766
4226.1.128.0/17226.1.128.1 to 226.1.255.254226.1.255.25532,766
5226.2.0.0/17226.2.0.1 to 226.2.127.254226.2.127.25532,766
6226.2.128.0/17226.2.128.1 to 226.2.255.254226.2.255.25532,766
7226.3.0.0/17226.3.0.1 to 226.3.127.254226.3.127.25532,766
8226.3.128.0/17226.3.128.1 to 226.3.255.254226.3.255.25532,766
9226.4.0.0/17226.4.0.1 to 226.4.127.254226.4.127.25532,766
10226.4.128.0/17226.4.128.1 to 226.4.255.254226.4.255.25532,766
11226.5.0.0/17226.5.0.1 to 226.5.127.254226.5.127.25532,766
12226.5.128.0/17226.5.128.1 to 226.5.255.254226.5.255.25532,766
13226.6.0.0/17226.6.0.1 to 226.6.127.254226.6.127.25532,766
14226.6.128.0/17226.6.128.1 to 226.6.255.254226.6.255.25532,766
15226.7.0.0/17226.7.0.1 to 226.7.127.254226.7.127.25532,766
16226.7.128.0/17226.7.128.1 to 226.7.255.254226.7.255.25532,766
17226.8.0.0/17226.8.0.1 to 226.8.127.254226.8.127.25532,766
18226.8.128.0/17226.8.128.1 to 226.8.255.254226.8.255.25532,766
19226.9.0.0/17226.9.0.1 to 226.9.127.254226.9.127.25532,766
20226.9.128.0/17226.9.128.1 to 226.9.255.254226.9.255.25532,766
21226.10.0.0/17226.10.0.1 to 226.10.127.254226.10.127.25532,766
22226.10.128.0/17226.10.128.1 to 226.10.255.254226.10.255.25532,766
23226.11.0.0/17226.11.0.1 to 226.11.127.254226.11.127.25532,766
24226.11.128.0/17226.11.128.1 to 226.11.255.254226.11.255.25532,766
25226.12.0.0/17226.12.0.1 to 226.12.127.254226.12.127.25532,766
26226.12.128.0/17226.12.128.1 to 226.12.255.254226.12.255.25532,766
27226.13.0.0/17226.13.0.1 to 226.13.127.254226.13.127.25532,766
28226.13.128.0/17226.13.128.1 to 226.13.255.254226.13.255.25532,766
29226.14.0.0/17226.14.0.1 to 226.14.127.254226.14.127.25532,766
30226.14.128.0/17226.14.128.1 to 226.14.255.254226.14.255.25532,766
31226.15.0.0/17226.15.0.1 to 226.15.127.254226.15.127.25532,766
32226.15.128.0/17226.15.128.1 to 226.15.255.254226.15.255.25532,766
33226.16.0.0/17226.16.0.1 to 226.16.127.254226.16.127.25532,766
34226.16.128.0/17226.16.128.1 to 226.16.255.254226.16.255.25532,766
35226.17.0.0/17226.17.0.1 to 226.17.127.254226.17.127.25532,766
36226.17.128.0/17226.17.128.1 to 226.17.255.254226.17.255.25532,766
37226.18.0.0/17226.18.0.1 to 226.18.127.254226.18.127.25532,766
38226.18.128.0/17226.18.128.1 to 226.18.255.254226.18.255.25532,766
39226.19.0.0/17226.19.0.1 to 226.19.127.254226.19.127.25532,766
40226.19.128.0/17226.19.128.1 to 226.19.255.254226.19.255.25532,766
41226.20.0.0/17226.20.0.1 to 226.20.127.254226.20.127.25532,766
42226.20.128.0/17226.20.128.1 to 226.20.255.254226.20.255.25532,766
43226.21.0.0/17226.21.0.1 to 226.21.127.254226.21.127.25532,766
44226.21.128.0/17226.21.128.1 to 226.21.255.254226.21.255.25532,766
45226.22.0.0/17226.22.0.1 to 226.22.127.254226.22.127.25532,766
46226.22.128.0/17226.22.128.1 to 226.22.255.254226.22.255.25532,766
47226.23.0.0/17226.23.0.1 to 226.23.127.254226.23.127.25532,766
48226.23.128.0/17226.23.128.1 to 226.23.255.254226.23.255.25532,766
49226.24.0.0/17226.24.0.1 to 226.24.127.254226.24.127.25532,766
50226.24.128.0/17226.24.128.1 to 226.24.255.254226.24.255.25532,766
51226.25.0.0/17226.25.0.1 to 226.25.127.254226.25.127.25532,766
52226.25.128.0/17226.25.128.1 to 226.25.255.254226.25.255.25532,766
53226.26.0.0/17226.26.0.1 to 226.26.127.254226.26.127.25532,766
54226.26.128.0/17226.26.128.1 to 226.26.255.254226.26.255.25532,766
55226.27.0.0/17226.27.0.1 to 226.27.127.254226.27.127.25532,766
56226.27.128.0/17226.27.128.1 to 226.27.255.254226.27.255.25532,766
57226.28.0.0/17226.28.0.1 to 226.28.127.254226.28.127.25532,766
58226.28.128.0/17226.28.128.1 to 226.28.255.254226.28.255.25532,766
59226.29.0.0/17226.29.0.1 to 226.29.127.254226.29.127.25532,766
60226.29.128.0/17226.29.128.1 to 226.29.255.254226.29.255.25532,766
61226.30.0.0/17226.30.0.1 to 226.30.127.254226.30.127.25532,766
62226.30.128.0/17226.30.128.1 to 226.30.255.254226.30.255.25532,766
63226.31.0.0/17226.31.0.1 to 226.31.127.254226.31.127.25532,766
64226.31.128.0/17226.31.128.1 to 226.31.255.254226.31.255.25532,766
65226.32.0.0/17226.32.0.1 to 226.32.127.254226.32.127.25532,766
66226.32.128.0/17226.32.128.1 to 226.32.255.254226.32.255.25532,766
67226.33.0.0/17226.33.0.1 to 226.33.127.254226.33.127.25532,766
68226.33.128.0/17226.33.128.1 to 226.33.255.254226.33.255.25532,766
69226.34.0.0/17226.34.0.1 to 226.34.127.254226.34.127.25532,766
70226.34.128.0/17226.34.128.1 to 226.34.255.254226.34.255.25532,766
71226.35.0.0/17226.35.0.1 to 226.35.127.254226.35.127.25532,766
72226.35.128.0/17226.35.128.1 to 226.35.255.254226.35.255.25532,766
73226.36.0.0/17226.36.0.1 to 226.36.127.254226.36.127.25532,766
74226.36.128.0/17226.36.128.1 to 226.36.255.254226.36.255.25532,766
75226.37.0.0/17226.37.0.1 to 226.37.127.254226.37.127.25532,766
76226.37.128.0/17226.37.128.1 to 226.37.255.254226.37.255.25532,766
77226.38.0.0/17226.38.0.1 to 226.38.127.254226.38.127.25532,766
78226.38.128.0/17226.38.128.1 to 226.38.255.254226.38.255.25532,766
79226.39.0.0/17226.39.0.1 to 226.39.127.254226.39.127.25532,766
80226.39.128.0/17226.39.128.1 to 226.39.255.254226.39.255.25532,766
81226.40.0.0/17226.40.0.1 to 226.40.127.254226.40.127.25532,766
82226.40.128.0/17226.40.128.1 to 226.40.255.254226.40.255.25532,766
83226.41.0.0/17226.41.0.1 to 226.41.127.254226.41.127.25532,766
84226.41.128.0/17226.41.128.1 to 226.41.255.254226.41.255.25532,766
85226.42.0.0/17226.42.0.1 to 226.42.127.254226.42.127.25532,766
86226.42.128.0/17226.42.128.1 to 226.42.255.254226.42.255.25532,766
87226.43.0.0/17226.43.0.1 to 226.43.127.254226.43.127.25532,766
88226.43.128.0/17226.43.128.1 to 226.43.255.254226.43.255.25532,766
89226.44.0.0/17226.44.0.1 to 226.44.127.254226.44.127.25532,766
90226.44.128.0/17226.44.128.1 to 226.44.255.254226.44.255.25532,766
91226.45.0.0/17226.45.0.1 to 226.45.127.254226.45.127.25532,766
92226.45.128.0/17226.45.128.1 to 226.45.255.254226.45.255.25532,766
93226.46.0.0/17226.46.0.1 to 226.46.127.254226.46.127.25532,766
94226.46.128.0/17226.46.128.1 to 226.46.255.254226.46.255.25532,766
95226.47.0.0/17226.47.0.1 to 226.47.127.254226.47.127.25532,766
96226.47.128.0/17226.47.128.1 to 226.47.255.254226.47.255.25532,766
97226.48.0.0/17226.48.0.1 to 226.48.127.254226.48.127.25532,766
98226.48.128.0/17226.48.128.1 to 226.48.255.254226.48.255.25532,766
99226.49.0.0/17226.49.0.1 to 226.49.127.254226.49.127.25532,766
100226.49.128.0/17226.49.128.1 to 226.49.255.254226.49.255.25532,766
101226.50.0.0/17226.50.0.1 to 226.50.127.254226.50.127.25532,766
102226.50.128.0/17226.50.128.1 to 226.50.255.254226.50.255.25532,766
103226.51.0.0/17226.51.0.1 to 226.51.127.254226.51.127.25532,766
104226.51.128.0/17226.51.128.1 to 226.51.255.254226.51.255.25532,766
105226.52.0.0/17226.52.0.1 to 226.52.127.254226.52.127.25532,766
106226.52.128.0/17226.52.128.1 to 226.52.255.254226.52.255.25532,766
107226.53.0.0/17226.53.0.1 to 226.53.127.254226.53.127.25532,766
108226.53.128.0/17226.53.128.1 to 226.53.255.254226.53.255.25532,766
109226.54.0.0/17226.54.0.1 to 226.54.127.254226.54.127.25532,766
110226.54.128.0/17226.54.128.1 to 226.54.255.254226.54.255.25532,766
111226.55.0.0/17226.55.0.1 to 226.55.127.254226.55.127.25532,766
112226.55.128.0/17226.55.128.1 to 226.55.255.254226.55.255.25532,766
113226.56.0.0/17226.56.0.1 to 226.56.127.254226.56.127.25532,766
114226.56.128.0/17226.56.128.1 to 226.56.255.254226.56.255.25532,766
115226.57.0.0/17226.57.0.1 to 226.57.127.254226.57.127.25532,766
116226.57.128.0/17226.57.128.1 to 226.57.255.254226.57.255.25532,766
117226.58.0.0/17226.58.0.1 to 226.58.127.254226.58.127.25532,766
118226.58.128.0/17226.58.128.1 to 226.58.255.254226.58.255.25532,766
119226.59.0.0/17226.59.0.1 to 226.59.127.254226.59.127.25532,766
120226.59.128.0/17226.59.128.1 to 226.59.255.254226.59.255.25532,766
121226.60.0.0/17226.60.0.1 to 226.60.127.254226.60.127.25532,766
122226.60.128.0/17226.60.128.1 to 226.60.255.254226.60.255.25532,766
123226.61.0.0/17226.61.0.1 to 226.61.127.254226.61.127.25532,766
124226.61.128.0/17226.61.128.1 to 226.61.255.254226.61.255.25532,766
125226.62.0.0/17226.62.0.1 to 226.62.127.254226.62.127.25532,766
126226.62.128.0/17226.62.128.1 to 226.62.255.254226.62.255.25532,766
127226.63.0.0/17226.63.0.1 to 226.63.127.254226.63.127.25532,766
128226.63.128.0/17226.63.128.1 to 226.63.255.254226.63.255.25532,766
129226.64.0.0/17226.64.0.1 to 226.64.127.254226.64.127.25532,766
130226.64.128.0/17226.64.128.1 to 226.64.255.254226.64.255.25532,766
131226.65.0.0/17226.65.0.1 to 226.65.127.254226.65.127.25532,766
132226.65.128.0/17226.65.128.1 to 226.65.255.254226.65.255.25532,766
133226.66.0.0/17226.66.0.1 to 226.66.127.254226.66.127.25532,766
134226.66.128.0/17226.66.128.1 to 226.66.255.254226.66.255.25532,766
135226.67.0.0/17226.67.0.1 to 226.67.127.254226.67.127.25532,766
136226.67.128.0/17226.67.128.1 to 226.67.255.254226.67.255.25532,766
137226.68.0.0/17226.68.0.1 to 226.68.127.254226.68.127.25532,766
138226.68.128.0/17226.68.128.1 to 226.68.255.254226.68.255.25532,766
139226.69.0.0/17226.69.0.1 to 226.69.127.254226.69.127.25532,766
140226.69.128.0/17226.69.128.1 to 226.69.255.254226.69.255.25532,766
141226.70.0.0/17226.70.0.1 to 226.70.127.254226.70.127.25532,766
142226.70.128.0/17226.70.128.1 to 226.70.255.254226.70.255.25532,766
143226.71.0.0/17226.71.0.1 to 226.71.127.254226.71.127.25532,766
144226.71.128.0/17226.71.128.1 to 226.71.255.254226.71.255.25532,766
145226.72.0.0/17226.72.0.1 to 226.72.127.254226.72.127.25532,766
146226.72.128.0/17226.72.128.1 to 226.72.255.254226.72.255.25532,766
147226.73.0.0/17226.73.0.1 to 226.73.127.254226.73.127.25532,766
148226.73.128.0/17226.73.128.1 to 226.73.255.254226.73.255.25532,766
149226.74.0.0/17226.74.0.1 to 226.74.127.254226.74.127.25532,766
150226.74.128.0/17226.74.128.1 to 226.74.255.254226.74.255.25532,766
151226.75.0.0/17226.75.0.1 to 226.75.127.254226.75.127.25532,766
152226.75.128.0/17226.75.128.1 to 226.75.255.254226.75.255.25532,766
153226.76.0.0/17226.76.0.1 to 226.76.127.254226.76.127.25532,766
154226.76.128.0/17226.76.128.1 to 226.76.255.254226.76.255.25532,766
155226.77.0.0/17226.77.0.1 to 226.77.127.254226.77.127.25532,766
156226.77.128.0/17226.77.128.1 to 226.77.255.254226.77.255.25532,766
157226.78.0.0/17226.78.0.1 to 226.78.127.254226.78.127.25532,766
158226.78.128.0/17226.78.128.1 to 226.78.255.254226.78.255.25532,766
159226.79.0.0/17226.79.0.1 to 226.79.127.254226.79.127.25532,766
160226.79.128.0/17226.79.128.1 to 226.79.255.254226.79.255.25532,766
161226.80.0.0/17226.80.0.1 to 226.80.127.254226.80.127.25532,766
162226.80.128.0/17226.80.128.1 to 226.80.255.254226.80.255.25532,766
163226.81.0.0/17226.81.0.1 to 226.81.127.254226.81.127.25532,766
164226.81.128.0/17226.81.128.1 to 226.81.255.254226.81.255.25532,766
165226.82.0.0/17226.82.0.1 to 226.82.127.254226.82.127.25532,766
166226.82.128.0/17226.82.128.1 to 226.82.255.254226.82.255.25532,766
167226.83.0.0/17226.83.0.1 to 226.83.127.254226.83.127.25532,766
168226.83.128.0/17226.83.128.1 to 226.83.255.254226.83.255.25532,766
169226.84.0.0/17226.84.0.1 to 226.84.127.254226.84.127.25532,766
170226.84.128.0/17226.84.128.1 to 226.84.255.254226.84.255.25532,766
171226.85.0.0/17226.85.0.1 to 226.85.127.254226.85.127.25532,766
172226.85.128.0/17226.85.128.1 to 226.85.255.254226.85.255.25532,766
173226.86.0.0/17226.86.0.1 to 226.86.127.254226.86.127.25532,766
174226.86.128.0/17226.86.128.1 to 226.86.255.254226.86.255.25532,766
175226.87.0.0/17226.87.0.1 to 226.87.127.254226.87.127.25532,766
176226.87.128.0/17226.87.128.1 to 226.87.255.254226.87.255.25532,766
177226.88.0.0/17226.88.0.1 to 226.88.127.254226.88.127.25532,766
178226.88.128.0/17226.88.128.1 to 226.88.255.254226.88.255.25532,766
179226.89.0.0/17226.89.0.1 to 226.89.127.254226.89.127.25532,766
180226.89.128.0/17226.89.128.1 to 226.89.255.254226.89.255.25532,766
181226.90.0.0/17226.90.0.1 to 226.90.127.254226.90.127.25532,766
182226.90.128.0/17226.90.128.1 to 226.90.255.254226.90.255.25532,766
183226.91.0.0/17226.91.0.1 to 226.91.127.254226.91.127.25532,766
184226.91.128.0/17226.91.128.1 to 226.91.255.254226.91.255.25532,766
185226.92.0.0/17226.92.0.1 to 226.92.127.254226.92.127.25532,766
186226.92.128.0/17226.92.128.1 to 226.92.255.254226.92.255.25532,766
187226.93.0.0/17226.93.0.1 to 226.93.127.254226.93.127.25532,766
188226.93.128.0/17226.93.128.1 to 226.93.255.254226.93.255.25532,766
189226.94.0.0/17226.94.0.1 to 226.94.127.254226.94.127.25532,766
190226.94.128.0/17226.94.128.1 to 226.94.255.254226.94.255.25532,766
191226.95.0.0/17226.95.0.1 to 226.95.127.254226.95.127.25532,766
192226.95.128.0/17226.95.128.1 to 226.95.255.254226.95.255.25532,766
193226.96.0.0/17226.96.0.1 to 226.96.127.254226.96.127.25532,766
194226.96.128.0/17226.96.128.1 to 226.96.255.254226.96.255.25532,766
195226.97.0.0/17226.97.0.1 to 226.97.127.254226.97.127.25532,766
196226.97.128.0/17226.97.128.1 to 226.97.255.254226.97.255.25532,766
197226.98.0.0/17226.98.0.1 to 226.98.127.254226.98.127.25532,766
198226.98.128.0/17226.98.128.1 to 226.98.255.254226.98.255.25532,766
199226.99.0.0/17226.99.0.1 to 226.99.127.254226.99.127.25532,766
200226.99.128.0/17226.99.128.1 to 226.99.255.254226.99.255.25532,766
201226.100.0.0/17226.100.0.1 to 226.100.127.254226.100.127.25532,766
202226.100.128.0/17226.100.128.1 to 226.100.255.254226.100.255.25532,766
203226.101.0.0/17226.101.0.1 to 226.101.127.254226.101.127.25532,766
204226.101.128.0/17226.101.128.1 to 226.101.255.254226.101.255.25532,766
205226.102.0.0/17226.102.0.1 to 226.102.127.254226.102.127.25532,766
206226.102.128.0/17226.102.128.1 to 226.102.255.254226.102.255.25532,766
207226.103.0.0/17226.103.0.1 to 226.103.127.254226.103.127.25532,766
208226.103.128.0/17226.103.128.1 to 226.103.255.254226.103.255.25532,766
209226.104.0.0/17226.104.0.1 to 226.104.127.254226.104.127.25532,766
210226.104.128.0/17226.104.128.1 to 226.104.255.254226.104.255.25532,766
211226.105.0.0/17226.105.0.1 to 226.105.127.254226.105.127.25532,766
212226.105.128.0/17226.105.128.1 to 226.105.255.254226.105.255.25532,766
213226.106.0.0/17226.106.0.1 to 226.106.127.254226.106.127.25532,766
214226.106.128.0/17226.106.128.1 to 226.106.255.254226.106.255.25532,766
215226.107.0.0/17226.107.0.1 to 226.107.127.254226.107.127.25532,766
216226.107.128.0/17226.107.128.1 to 226.107.255.254226.107.255.25532,766
217226.108.0.0/17226.108.0.1 to 226.108.127.254226.108.127.25532,766
218226.108.128.0/17226.108.128.1 to 226.108.255.254226.108.255.25532,766
219226.109.0.0/17226.109.0.1 to 226.109.127.254226.109.127.25532,766
220226.109.128.0/17226.109.128.1 to 226.109.255.254226.109.255.25532,766
221226.110.0.0/17226.110.0.1 to 226.110.127.254226.110.127.25532,766
222226.110.128.0/17226.110.128.1 to 226.110.255.254226.110.255.25532,766
223226.111.0.0/17226.111.0.1 to 226.111.127.254226.111.127.25532,766
224226.111.128.0/17226.111.128.1 to 226.111.255.254226.111.255.25532,766
225226.112.0.0/17226.112.0.1 to 226.112.127.254226.112.127.25532,766
226226.112.128.0/17226.112.128.1 to 226.112.255.254226.112.255.25532,766
227226.113.0.0/17226.113.0.1 to 226.113.127.254226.113.127.25532,766
228226.113.128.0/17226.113.128.1 to 226.113.255.254226.113.255.25532,766
229226.114.0.0/17226.114.0.1 to 226.114.127.254226.114.127.25532,766
230226.114.128.0/17226.114.128.1 to 226.114.255.254226.114.255.25532,766
231226.115.0.0/17226.115.0.1 to 226.115.127.254226.115.127.25532,766
232226.115.128.0/17226.115.128.1 to 226.115.255.254226.115.255.25532,766
233226.116.0.0/17226.116.0.1 to 226.116.127.254226.116.127.25532,766
234226.116.128.0/17226.116.128.1 to 226.116.255.254226.116.255.25532,766
235226.117.0.0/17226.117.0.1 to 226.117.127.254226.117.127.25532,766
236226.117.128.0/17226.117.128.1 to 226.117.255.254226.117.255.25532,766
237226.118.0.0/17226.118.0.1 to 226.118.127.254226.118.127.25532,766
238226.118.128.0/17226.118.128.1 to 226.118.255.254226.118.255.25532,766
239226.119.0.0/17226.119.0.1 to 226.119.127.254226.119.127.25532,766
240226.119.128.0/17226.119.128.1 to 226.119.255.254226.119.255.25532,766
241226.120.0.0/17226.120.0.1 to 226.120.127.254226.120.127.25532,766
242226.120.128.0/17226.120.128.1 to 226.120.255.254226.120.255.25532,766
243226.121.0.0/17226.121.0.1 to 226.121.127.254226.121.127.25532,766
244226.121.128.0/17226.121.128.1 to 226.121.255.254226.121.255.25532,766
245226.122.0.0/17226.122.0.1 to 226.122.127.254226.122.127.25532,766
246226.122.128.0/17226.122.128.1 to 226.122.255.254226.122.255.25532,766
247226.123.0.0/17226.123.0.1 to 226.123.127.254226.123.127.25532,766
248226.123.128.0/17226.123.128.1 to 226.123.255.254226.123.255.25532,766
249226.124.0.0/17226.124.0.1 to 226.124.127.254226.124.127.25532,766
250226.124.128.0/17226.124.128.1 to 226.124.255.254226.124.255.25532,766
251226.125.0.0/17226.125.0.1 to 226.125.127.254226.125.127.25532,766
252226.125.128.0/17226.125.128.1 to 226.125.255.254226.125.255.25532,766
253226.126.0.0/17226.126.0.1 to 226.126.127.254226.126.127.25532,766
254226.126.128.0/17226.126.128.1 to 226.126.255.254226.126.255.25532,766
255226.127.0.0/17226.127.0.1 to 226.127.127.254226.127.127.25532,766
256226.127.128.0/17226.127.128.1 to 226.127.255.254226.127.255.25532,766

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.