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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.

Network222.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
222.0.0.0
Broadcast address
222.255.255.255
First usable
222.0.0.1
Last usable
222.255.255.254
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
Public public
Old class
C (default /24)
As numbers
Hex DE000000 · Integer 3724541952 to 3741319167
Reverse DNS zone
222.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11011110..00000000.00000000.00000000222.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network11011110..00000000.00000000.00000000222.0.0.0
Broadcast11011110..11111111.11111111.11111111222.255.255.255
Split into smaller subnets/17
/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)

222.0.0.0/8 makes 512 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1222.0.0.0/17222.0.0.1 to 222.0.127.254222.0.127.25532,766
2222.0.128.0/17222.0.128.1 to 222.0.255.254222.0.255.25532,766
3222.1.0.0/17222.1.0.1 to 222.1.127.254222.1.127.25532,766
4222.1.128.0/17222.1.128.1 to 222.1.255.254222.1.255.25532,766
5222.2.0.0/17222.2.0.1 to 222.2.127.254222.2.127.25532,766
6222.2.128.0/17222.2.128.1 to 222.2.255.254222.2.255.25532,766
7222.3.0.0/17222.3.0.1 to 222.3.127.254222.3.127.25532,766
8222.3.128.0/17222.3.128.1 to 222.3.255.254222.3.255.25532,766
9222.4.0.0/17222.4.0.1 to 222.4.127.254222.4.127.25532,766
10222.4.128.0/17222.4.128.1 to 222.4.255.254222.4.255.25532,766
11222.5.0.0/17222.5.0.1 to 222.5.127.254222.5.127.25532,766
12222.5.128.0/17222.5.128.1 to 222.5.255.254222.5.255.25532,766
13222.6.0.0/17222.6.0.1 to 222.6.127.254222.6.127.25532,766
14222.6.128.0/17222.6.128.1 to 222.6.255.254222.6.255.25532,766
15222.7.0.0/17222.7.0.1 to 222.7.127.254222.7.127.25532,766
16222.7.128.0/17222.7.128.1 to 222.7.255.254222.7.255.25532,766
17222.8.0.0/17222.8.0.1 to 222.8.127.254222.8.127.25532,766
18222.8.128.0/17222.8.128.1 to 222.8.255.254222.8.255.25532,766
19222.9.0.0/17222.9.0.1 to 222.9.127.254222.9.127.25532,766
20222.9.128.0/17222.9.128.1 to 222.9.255.254222.9.255.25532,766
21222.10.0.0/17222.10.0.1 to 222.10.127.254222.10.127.25532,766
22222.10.128.0/17222.10.128.1 to 222.10.255.254222.10.255.25532,766
23222.11.0.0/17222.11.0.1 to 222.11.127.254222.11.127.25532,766
24222.11.128.0/17222.11.128.1 to 222.11.255.254222.11.255.25532,766
25222.12.0.0/17222.12.0.1 to 222.12.127.254222.12.127.25532,766
26222.12.128.0/17222.12.128.1 to 222.12.255.254222.12.255.25532,766
27222.13.0.0/17222.13.0.1 to 222.13.127.254222.13.127.25532,766
28222.13.128.0/17222.13.128.1 to 222.13.255.254222.13.255.25532,766
29222.14.0.0/17222.14.0.1 to 222.14.127.254222.14.127.25532,766
30222.14.128.0/17222.14.128.1 to 222.14.255.254222.14.255.25532,766
31222.15.0.0/17222.15.0.1 to 222.15.127.254222.15.127.25532,766
32222.15.128.0/17222.15.128.1 to 222.15.255.254222.15.255.25532,766
33222.16.0.0/17222.16.0.1 to 222.16.127.254222.16.127.25532,766
34222.16.128.0/17222.16.128.1 to 222.16.255.254222.16.255.25532,766
35222.17.0.0/17222.17.0.1 to 222.17.127.254222.17.127.25532,766
36222.17.128.0/17222.17.128.1 to 222.17.255.254222.17.255.25532,766
37222.18.0.0/17222.18.0.1 to 222.18.127.254222.18.127.25532,766
38222.18.128.0/17222.18.128.1 to 222.18.255.254222.18.255.25532,766
39222.19.0.0/17222.19.0.1 to 222.19.127.254222.19.127.25532,766
40222.19.128.0/17222.19.128.1 to 222.19.255.254222.19.255.25532,766
41222.20.0.0/17222.20.0.1 to 222.20.127.254222.20.127.25532,766
42222.20.128.0/17222.20.128.1 to 222.20.255.254222.20.255.25532,766
43222.21.0.0/17222.21.0.1 to 222.21.127.254222.21.127.25532,766
44222.21.128.0/17222.21.128.1 to 222.21.255.254222.21.255.25532,766
45222.22.0.0/17222.22.0.1 to 222.22.127.254222.22.127.25532,766
46222.22.128.0/17222.22.128.1 to 222.22.255.254222.22.255.25532,766
47222.23.0.0/17222.23.0.1 to 222.23.127.254222.23.127.25532,766
48222.23.128.0/17222.23.128.1 to 222.23.255.254222.23.255.25532,766
49222.24.0.0/17222.24.0.1 to 222.24.127.254222.24.127.25532,766
50222.24.128.0/17222.24.128.1 to 222.24.255.254222.24.255.25532,766
51222.25.0.0/17222.25.0.1 to 222.25.127.254222.25.127.25532,766
52222.25.128.0/17222.25.128.1 to 222.25.255.254222.25.255.25532,766
53222.26.0.0/17222.26.0.1 to 222.26.127.254222.26.127.25532,766
54222.26.128.0/17222.26.128.1 to 222.26.255.254222.26.255.25532,766
55222.27.0.0/17222.27.0.1 to 222.27.127.254222.27.127.25532,766
56222.27.128.0/17222.27.128.1 to 222.27.255.254222.27.255.25532,766
57222.28.0.0/17222.28.0.1 to 222.28.127.254222.28.127.25532,766
58222.28.128.0/17222.28.128.1 to 222.28.255.254222.28.255.25532,766
59222.29.0.0/17222.29.0.1 to 222.29.127.254222.29.127.25532,766
60222.29.128.0/17222.29.128.1 to 222.29.255.254222.29.255.25532,766
61222.30.0.0/17222.30.0.1 to 222.30.127.254222.30.127.25532,766
62222.30.128.0/17222.30.128.1 to 222.30.255.254222.30.255.25532,766
63222.31.0.0/17222.31.0.1 to 222.31.127.254222.31.127.25532,766
64222.31.128.0/17222.31.128.1 to 222.31.255.254222.31.255.25532,766
65222.32.0.0/17222.32.0.1 to 222.32.127.254222.32.127.25532,766
66222.32.128.0/17222.32.128.1 to 222.32.255.254222.32.255.25532,766
67222.33.0.0/17222.33.0.1 to 222.33.127.254222.33.127.25532,766
68222.33.128.0/17222.33.128.1 to 222.33.255.254222.33.255.25532,766
69222.34.0.0/17222.34.0.1 to 222.34.127.254222.34.127.25532,766
70222.34.128.0/17222.34.128.1 to 222.34.255.254222.34.255.25532,766
71222.35.0.0/17222.35.0.1 to 222.35.127.254222.35.127.25532,766
72222.35.128.0/17222.35.128.1 to 222.35.255.254222.35.255.25532,766
73222.36.0.0/17222.36.0.1 to 222.36.127.254222.36.127.25532,766
74222.36.128.0/17222.36.128.1 to 222.36.255.254222.36.255.25532,766
75222.37.0.0/17222.37.0.1 to 222.37.127.254222.37.127.25532,766
76222.37.128.0/17222.37.128.1 to 222.37.255.254222.37.255.25532,766
77222.38.0.0/17222.38.0.1 to 222.38.127.254222.38.127.25532,766
78222.38.128.0/17222.38.128.1 to 222.38.255.254222.38.255.25532,766
79222.39.0.0/17222.39.0.1 to 222.39.127.254222.39.127.25532,766
80222.39.128.0/17222.39.128.1 to 222.39.255.254222.39.255.25532,766
81222.40.0.0/17222.40.0.1 to 222.40.127.254222.40.127.25532,766
82222.40.128.0/17222.40.128.1 to 222.40.255.254222.40.255.25532,766
83222.41.0.0/17222.41.0.1 to 222.41.127.254222.41.127.25532,766
84222.41.128.0/17222.41.128.1 to 222.41.255.254222.41.255.25532,766
85222.42.0.0/17222.42.0.1 to 222.42.127.254222.42.127.25532,766
86222.42.128.0/17222.42.128.1 to 222.42.255.254222.42.255.25532,766
87222.43.0.0/17222.43.0.1 to 222.43.127.254222.43.127.25532,766
88222.43.128.0/17222.43.128.1 to 222.43.255.254222.43.255.25532,766
89222.44.0.0/17222.44.0.1 to 222.44.127.254222.44.127.25532,766
90222.44.128.0/17222.44.128.1 to 222.44.255.254222.44.255.25532,766
91222.45.0.0/17222.45.0.1 to 222.45.127.254222.45.127.25532,766
92222.45.128.0/17222.45.128.1 to 222.45.255.254222.45.255.25532,766
93222.46.0.0/17222.46.0.1 to 222.46.127.254222.46.127.25532,766
94222.46.128.0/17222.46.128.1 to 222.46.255.254222.46.255.25532,766
95222.47.0.0/17222.47.0.1 to 222.47.127.254222.47.127.25532,766
96222.47.128.0/17222.47.128.1 to 222.47.255.254222.47.255.25532,766
97222.48.0.0/17222.48.0.1 to 222.48.127.254222.48.127.25532,766
98222.48.128.0/17222.48.128.1 to 222.48.255.254222.48.255.25532,766
99222.49.0.0/17222.49.0.1 to 222.49.127.254222.49.127.25532,766
100222.49.128.0/17222.49.128.1 to 222.49.255.254222.49.255.25532,766
101222.50.0.0/17222.50.0.1 to 222.50.127.254222.50.127.25532,766
102222.50.128.0/17222.50.128.1 to 222.50.255.254222.50.255.25532,766
103222.51.0.0/17222.51.0.1 to 222.51.127.254222.51.127.25532,766
104222.51.128.0/17222.51.128.1 to 222.51.255.254222.51.255.25532,766
105222.52.0.0/17222.52.0.1 to 222.52.127.254222.52.127.25532,766
106222.52.128.0/17222.52.128.1 to 222.52.255.254222.52.255.25532,766
107222.53.0.0/17222.53.0.1 to 222.53.127.254222.53.127.25532,766
108222.53.128.0/17222.53.128.1 to 222.53.255.254222.53.255.25532,766
109222.54.0.0/17222.54.0.1 to 222.54.127.254222.54.127.25532,766
110222.54.128.0/17222.54.128.1 to 222.54.255.254222.54.255.25532,766
111222.55.0.0/17222.55.0.1 to 222.55.127.254222.55.127.25532,766
112222.55.128.0/17222.55.128.1 to 222.55.255.254222.55.255.25532,766
113222.56.0.0/17222.56.0.1 to 222.56.127.254222.56.127.25532,766
114222.56.128.0/17222.56.128.1 to 222.56.255.254222.56.255.25532,766
115222.57.0.0/17222.57.0.1 to 222.57.127.254222.57.127.25532,766
116222.57.128.0/17222.57.128.1 to 222.57.255.254222.57.255.25532,766
117222.58.0.0/17222.58.0.1 to 222.58.127.254222.58.127.25532,766
118222.58.128.0/17222.58.128.1 to 222.58.255.254222.58.255.25532,766
119222.59.0.0/17222.59.0.1 to 222.59.127.254222.59.127.25532,766
120222.59.128.0/17222.59.128.1 to 222.59.255.254222.59.255.25532,766
121222.60.0.0/17222.60.0.1 to 222.60.127.254222.60.127.25532,766
122222.60.128.0/17222.60.128.1 to 222.60.255.254222.60.255.25532,766
123222.61.0.0/17222.61.0.1 to 222.61.127.254222.61.127.25532,766
124222.61.128.0/17222.61.128.1 to 222.61.255.254222.61.255.25532,766
125222.62.0.0/17222.62.0.1 to 222.62.127.254222.62.127.25532,766
126222.62.128.0/17222.62.128.1 to 222.62.255.254222.62.255.25532,766
127222.63.0.0/17222.63.0.1 to 222.63.127.254222.63.127.25532,766
128222.63.128.0/17222.63.128.1 to 222.63.255.254222.63.255.25532,766
129222.64.0.0/17222.64.0.1 to 222.64.127.254222.64.127.25532,766
130222.64.128.0/17222.64.128.1 to 222.64.255.254222.64.255.25532,766
131222.65.0.0/17222.65.0.1 to 222.65.127.254222.65.127.25532,766
132222.65.128.0/17222.65.128.1 to 222.65.255.254222.65.255.25532,766
133222.66.0.0/17222.66.0.1 to 222.66.127.254222.66.127.25532,766
134222.66.128.0/17222.66.128.1 to 222.66.255.254222.66.255.25532,766
135222.67.0.0/17222.67.0.1 to 222.67.127.254222.67.127.25532,766
136222.67.128.0/17222.67.128.1 to 222.67.255.254222.67.255.25532,766
137222.68.0.0/17222.68.0.1 to 222.68.127.254222.68.127.25532,766
138222.68.128.0/17222.68.128.1 to 222.68.255.254222.68.255.25532,766
139222.69.0.0/17222.69.0.1 to 222.69.127.254222.69.127.25532,766
140222.69.128.0/17222.69.128.1 to 222.69.255.254222.69.255.25532,766
141222.70.0.0/17222.70.0.1 to 222.70.127.254222.70.127.25532,766
142222.70.128.0/17222.70.128.1 to 222.70.255.254222.70.255.25532,766
143222.71.0.0/17222.71.0.1 to 222.71.127.254222.71.127.25532,766
144222.71.128.0/17222.71.128.1 to 222.71.255.254222.71.255.25532,766
145222.72.0.0/17222.72.0.1 to 222.72.127.254222.72.127.25532,766
146222.72.128.0/17222.72.128.1 to 222.72.255.254222.72.255.25532,766
147222.73.0.0/17222.73.0.1 to 222.73.127.254222.73.127.25532,766
148222.73.128.0/17222.73.128.1 to 222.73.255.254222.73.255.25532,766
149222.74.0.0/17222.74.0.1 to 222.74.127.254222.74.127.25532,766
150222.74.128.0/17222.74.128.1 to 222.74.255.254222.74.255.25532,766
151222.75.0.0/17222.75.0.1 to 222.75.127.254222.75.127.25532,766
152222.75.128.0/17222.75.128.1 to 222.75.255.254222.75.255.25532,766
153222.76.0.0/17222.76.0.1 to 222.76.127.254222.76.127.25532,766
154222.76.128.0/17222.76.128.1 to 222.76.255.254222.76.255.25532,766
155222.77.0.0/17222.77.0.1 to 222.77.127.254222.77.127.25532,766
156222.77.128.0/17222.77.128.1 to 222.77.255.254222.77.255.25532,766
157222.78.0.0/17222.78.0.1 to 222.78.127.254222.78.127.25532,766
158222.78.128.0/17222.78.128.1 to 222.78.255.254222.78.255.25532,766
159222.79.0.0/17222.79.0.1 to 222.79.127.254222.79.127.25532,766
160222.79.128.0/17222.79.128.1 to 222.79.255.254222.79.255.25532,766
161222.80.0.0/17222.80.0.1 to 222.80.127.254222.80.127.25532,766
162222.80.128.0/17222.80.128.1 to 222.80.255.254222.80.255.25532,766
163222.81.0.0/17222.81.0.1 to 222.81.127.254222.81.127.25532,766
164222.81.128.0/17222.81.128.1 to 222.81.255.254222.81.255.25532,766
165222.82.0.0/17222.82.0.1 to 222.82.127.254222.82.127.25532,766
166222.82.128.0/17222.82.128.1 to 222.82.255.254222.82.255.25532,766
167222.83.0.0/17222.83.0.1 to 222.83.127.254222.83.127.25532,766
168222.83.128.0/17222.83.128.1 to 222.83.255.254222.83.255.25532,766
169222.84.0.0/17222.84.0.1 to 222.84.127.254222.84.127.25532,766
170222.84.128.0/17222.84.128.1 to 222.84.255.254222.84.255.25532,766
171222.85.0.0/17222.85.0.1 to 222.85.127.254222.85.127.25532,766
172222.85.128.0/17222.85.128.1 to 222.85.255.254222.85.255.25532,766
173222.86.0.0/17222.86.0.1 to 222.86.127.254222.86.127.25532,766
174222.86.128.0/17222.86.128.1 to 222.86.255.254222.86.255.25532,766
175222.87.0.0/17222.87.0.1 to 222.87.127.254222.87.127.25532,766
176222.87.128.0/17222.87.128.1 to 222.87.255.254222.87.255.25532,766
177222.88.0.0/17222.88.0.1 to 222.88.127.254222.88.127.25532,766
178222.88.128.0/17222.88.128.1 to 222.88.255.254222.88.255.25532,766
179222.89.0.0/17222.89.0.1 to 222.89.127.254222.89.127.25532,766
180222.89.128.0/17222.89.128.1 to 222.89.255.254222.89.255.25532,766
181222.90.0.0/17222.90.0.1 to 222.90.127.254222.90.127.25532,766
182222.90.128.0/17222.90.128.1 to 222.90.255.254222.90.255.25532,766
183222.91.0.0/17222.91.0.1 to 222.91.127.254222.91.127.25532,766
184222.91.128.0/17222.91.128.1 to 222.91.255.254222.91.255.25532,766
185222.92.0.0/17222.92.0.1 to 222.92.127.254222.92.127.25532,766
186222.92.128.0/17222.92.128.1 to 222.92.255.254222.92.255.25532,766
187222.93.0.0/17222.93.0.1 to 222.93.127.254222.93.127.25532,766
188222.93.128.0/17222.93.128.1 to 222.93.255.254222.93.255.25532,766
189222.94.0.0/17222.94.0.1 to 222.94.127.254222.94.127.25532,766
190222.94.128.0/17222.94.128.1 to 222.94.255.254222.94.255.25532,766
191222.95.0.0/17222.95.0.1 to 222.95.127.254222.95.127.25532,766
192222.95.128.0/17222.95.128.1 to 222.95.255.254222.95.255.25532,766
193222.96.0.0/17222.96.0.1 to 222.96.127.254222.96.127.25532,766
194222.96.128.0/17222.96.128.1 to 222.96.255.254222.96.255.25532,766
195222.97.0.0/17222.97.0.1 to 222.97.127.254222.97.127.25532,766
196222.97.128.0/17222.97.128.1 to 222.97.255.254222.97.255.25532,766
197222.98.0.0/17222.98.0.1 to 222.98.127.254222.98.127.25532,766
198222.98.128.0/17222.98.128.1 to 222.98.255.254222.98.255.25532,766
199222.99.0.0/17222.99.0.1 to 222.99.127.254222.99.127.25532,766
200222.99.128.0/17222.99.128.1 to 222.99.255.254222.99.255.25532,766
201222.100.0.0/17222.100.0.1 to 222.100.127.254222.100.127.25532,766
202222.100.128.0/17222.100.128.1 to 222.100.255.254222.100.255.25532,766
203222.101.0.0/17222.101.0.1 to 222.101.127.254222.101.127.25532,766
204222.101.128.0/17222.101.128.1 to 222.101.255.254222.101.255.25532,766
205222.102.0.0/17222.102.0.1 to 222.102.127.254222.102.127.25532,766
206222.102.128.0/17222.102.128.1 to 222.102.255.254222.102.255.25532,766
207222.103.0.0/17222.103.0.1 to 222.103.127.254222.103.127.25532,766
208222.103.128.0/17222.103.128.1 to 222.103.255.254222.103.255.25532,766
209222.104.0.0/17222.104.0.1 to 222.104.127.254222.104.127.25532,766
210222.104.128.0/17222.104.128.1 to 222.104.255.254222.104.255.25532,766
211222.105.0.0/17222.105.0.1 to 222.105.127.254222.105.127.25532,766
212222.105.128.0/17222.105.128.1 to 222.105.255.254222.105.255.25532,766
213222.106.0.0/17222.106.0.1 to 222.106.127.254222.106.127.25532,766
214222.106.128.0/17222.106.128.1 to 222.106.255.254222.106.255.25532,766
215222.107.0.0/17222.107.0.1 to 222.107.127.254222.107.127.25532,766
216222.107.128.0/17222.107.128.1 to 222.107.255.254222.107.255.25532,766
217222.108.0.0/17222.108.0.1 to 222.108.127.254222.108.127.25532,766
218222.108.128.0/17222.108.128.1 to 222.108.255.254222.108.255.25532,766
219222.109.0.0/17222.109.0.1 to 222.109.127.254222.109.127.25532,766
220222.109.128.0/17222.109.128.1 to 222.109.255.254222.109.255.25532,766
221222.110.0.0/17222.110.0.1 to 222.110.127.254222.110.127.25532,766
222222.110.128.0/17222.110.128.1 to 222.110.255.254222.110.255.25532,766
223222.111.0.0/17222.111.0.1 to 222.111.127.254222.111.127.25532,766
224222.111.128.0/17222.111.128.1 to 222.111.255.254222.111.255.25532,766
225222.112.0.0/17222.112.0.1 to 222.112.127.254222.112.127.25532,766
226222.112.128.0/17222.112.128.1 to 222.112.255.254222.112.255.25532,766
227222.113.0.0/17222.113.0.1 to 222.113.127.254222.113.127.25532,766
228222.113.128.0/17222.113.128.1 to 222.113.255.254222.113.255.25532,766
229222.114.0.0/17222.114.0.1 to 222.114.127.254222.114.127.25532,766
230222.114.128.0/17222.114.128.1 to 222.114.255.254222.114.255.25532,766
231222.115.0.0/17222.115.0.1 to 222.115.127.254222.115.127.25532,766
232222.115.128.0/17222.115.128.1 to 222.115.255.254222.115.255.25532,766
233222.116.0.0/17222.116.0.1 to 222.116.127.254222.116.127.25532,766
234222.116.128.0/17222.116.128.1 to 222.116.255.254222.116.255.25532,766
235222.117.0.0/17222.117.0.1 to 222.117.127.254222.117.127.25532,766
236222.117.128.0/17222.117.128.1 to 222.117.255.254222.117.255.25532,766
237222.118.0.0/17222.118.0.1 to 222.118.127.254222.118.127.25532,766
238222.118.128.0/17222.118.128.1 to 222.118.255.254222.118.255.25532,766
239222.119.0.0/17222.119.0.1 to 222.119.127.254222.119.127.25532,766
240222.119.128.0/17222.119.128.1 to 222.119.255.254222.119.255.25532,766
241222.120.0.0/17222.120.0.1 to 222.120.127.254222.120.127.25532,766
242222.120.128.0/17222.120.128.1 to 222.120.255.254222.120.255.25532,766
243222.121.0.0/17222.121.0.1 to 222.121.127.254222.121.127.25532,766
244222.121.128.0/17222.121.128.1 to 222.121.255.254222.121.255.25532,766
245222.122.0.0/17222.122.0.1 to 222.122.127.254222.122.127.25532,766
246222.122.128.0/17222.122.128.1 to 222.122.255.254222.122.255.25532,766
247222.123.0.0/17222.123.0.1 to 222.123.127.254222.123.127.25532,766
248222.123.128.0/17222.123.128.1 to 222.123.255.254222.123.255.25532,766
249222.124.0.0/17222.124.0.1 to 222.124.127.254222.124.127.25532,766
250222.124.128.0/17222.124.128.1 to 222.124.255.254222.124.255.25532,766
251222.125.0.0/17222.125.0.1 to 222.125.127.254222.125.127.25532,766
252222.125.128.0/17222.125.128.1 to 222.125.255.254222.125.255.25532,766
253222.126.0.0/17222.126.0.1 to 222.126.127.254222.126.127.25532,766
254222.126.128.0/17222.126.128.1 to 222.126.255.254222.126.255.25532,766
255222.127.0.0/17222.127.0.1 to 222.127.127.254222.127.127.25532,766
256222.127.128.0/17222.127.128.1 to 222.127.255.254222.127.255.25532,766

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.