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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/20
/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 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1222.0.0.0/20222.0.0.1 to 222.0.15.254222.0.15.2554,094
2222.0.16.0/20222.0.16.1 to 222.0.31.254222.0.31.2554,094
3222.0.32.0/20222.0.32.1 to 222.0.47.254222.0.47.2554,094
4222.0.48.0/20222.0.48.1 to 222.0.63.254222.0.63.2554,094
5222.0.64.0/20222.0.64.1 to 222.0.79.254222.0.79.2554,094
6222.0.80.0/20222.0.80.1 to 222.0.95.254222.0.95.2554,094
7222.0.96.0/20222.0.96.1 to 222.0.111.254222.0.111.2554,094
8222.0.112.0/20222.0.112.1 to 222.0.127.254222.0.127.2554,094
9222.0.128.0/20222.0.128.1 to 222.0.143.254222.0.143.2554,094
10222.0.144.0/20222.0.144.1 to 222.0.159.254222.0.159.2554,094
11222.0.160.0/20222.0.160.1 to 222.0.175.254222.0.175.2554,094
12222.0.176.0/20222.0.176.1 to 222.0.191.254222.0.191.2554,094
13222.0.192.0/20222.0.192.1 to 222.0.207.254222.0.207.2554,094
14222.0.208.0/20222.0.208.1 to 222.0.223.254222.0.223.2554,094
15222.0.224.0/20222.0.224.1 to 222.0.239.254222.0.239.2554,094
16222.0.240.0/20222.0.240.1 to 222.0.255.254222.0.255.2554,094
17222.1.0.0/20222.1.0.1 to 222.1.15.254222.1.15.2554,094
18222.1.16.0/20222.1.16.1 to 222.1.31.254222.1.31.2554,094
19222.1.32.0/20222.1.32.1 to 222.1.47.254222.1.47.2554,094
20222.1.48.0/20222.1.48.1 to 222.1.63.254222.1.63.2554,094
21222.1.64.0/20222.1.64.1 to 222.1.79.254222.1.79.2554,094
22222.1.80.0/20222.1.80.1 to 222.1.95.254222.1.95.2554,094
23222.1.96.0/20222.1.96.1 to 222.1.111.254222.1.111.2554,094
24222.1.112.0/20222.1.112.1 to 222.1.127.254222.1.127.2554,094
25222.1.128.0/20222.1.128.1 to 222.1.143.254222.1.143.2554,094
26222.1.144.0/20222.1.144.1 to 222.1.159.254222.1.159.2554,094
27222.1.160.0/20222.1.160.1 to 222.1.175.254222.1.175.2554,094
28222.1.176.0/20222.1.176.1 to 222.1.191.254222.1.191.2554,094
29222.1.192.0/20222.1.192.1 to 222.1.207.254222.1.207.2554,094
30222.1.208.0/20222.1.208.1 to 222.1.223.254222.1.223.2554,094
31222.1.224.0/20222.1.224.1 to 222.1.239.254222.1.239.2554,094
32222.1.240.0/20222.1.240.1 to 222.1.255.254222.1.255.2554,094
33222.2.0.0/20222.2.0.1 to 222.2.15.254222.2.15.2554,094
34222.2.16.0/20222.2.16.1 to 222.2.31.254222.2.31.2554,094
35222.2.32.0/20222.2.32.1 to 222.2.47.254222.2.47.2554,094
36222.2.48.0/20222.2.48.1 to 222.2.63.254222.2.63.2554,094
37222.2.64.0/20222.2.64.1 to 222.2.79.254222.2.79.2554,094
38222.2.80.0/20222.2.80.1 to 222.2.95.254222.2.95.2554,094
39222.2.96.0/20222.2.96.1 to 222.2.111.254222.2.111.2554,094
40222.2.112.0/20222.2.112.1 to 222.2.127.254222.2.127.2554,094
41222.2.128.0/20222.2.128.1 to 222.2.143.254222.2.143.2554,094
42222.2.144.0/20222.2.144.1 to 222.2.159.254222.2.159.2554,094
43222.2.160.0/20222.2.160.1 to 222.2.175.254222.2.175.2554,094
44222.2.176.0/20222.2.176.1 to 222.2.191.254222.2.191.2554,094
45222.2.192.0/20222.2.192.1 to 222.2.207.254222.2.207.2554,094
46222.2.208.0/20222.2.208.1 to 222.2.223.254222.2.223.2554,094
47222.2.224.0/20222.2.224.1 to 222.2.239.254222.2.239.2554,094
48222.2.240.0/20222.2.240.1 to 222.2.255.254222.2.255.2554,094
49222.3.0.0/20222.3.0.1 to 222.3.15.254222.3.15.2554,094
50222.3.16.0/20222.3.16.1 to 222.3.31.254222.3.31.2554,094
51222.3.32.0/20222.3.32.1 to 222.3.47.254222.3.47.2554,094
52222.3.48.0/20222.3.48.1 to 222.3.63.254222.3.63.2554,094
53222.3.64.0/20222.3.64.1 to 222.3.79.254222.3.79.2554,094
54222.3.80.0/20222.3.80.1 to 222.3.95.254222.3.95.2554,094
55222.3.96.0/20222.3.96.1 to 222.3.111.254222.3.111.2554,094
56222.3.112.0/20222.3.112.1 to 222.3.127.254222.3.127.2554,094
57222.3.128.0/20222.3.128.1 to 222.3.143.254222.3.143.2554,094
58222.3.144.0/20222.3.144.1 to 222.3.159.254222.3.159.2554,094
59222.3.160.0/20222.3.160.1 to 222.3.175.254222.3.175.2554,094
60222.3.176.0/20222.3.176.1 to 222.3.191.254222.3.191.2554,094
61222.3.192.0/20222.3.192.1 to 222.3.207.254222.3.207.2554,094
62222.3.208.0/20222.3.208.1 to 222.3.223.254222.3.223.2554,094
63222.3.224.0/20222.3.224.1 to 222.3.239.254222.3.239.2554,094
64222.3.240.0/20222.3.240.1 to 222.3.255.254222.3.255.2554,094
65222.4.0.0/20222.4.0.1 to 222.4.15.254222.4.15.2554,094
66222.4.16.0/20222.4.16.1 to 222.4.31.254222.4.31.2554,094
67222.4.32.0/20222.4.32.1 to 222.4.47.254222.4.47.2554,094
68222.4.48.0/20222.4.48.1 to 222.4.63.254222.4.63.2554,094
69222.4.64.0/20222.4.64.1 to 222.4.79.254222.4.79.2554,094
70222.4.80.0/20222.4.80.1 to 222.4.95.254222.4.95.2554,094
71222.4.96.0/20222.4.96.1 to 222.4.111.254222.4.111.2554,094
72222.4.112.0/20222.4.112.1 to 222.4.127.254222.4.127.2554,094
73222.4.128.0/20222.4.128.1 to 222.4.143.254222.4.143.2554,094
74222.4.144.0/20222.4.144.1 to 222.4.159.254222.4.159.2554,094
75222.4.160.0/20222.4.160.1 to 222.4.175.254222.4.175.2554,094
76222.4.176.0/20222.4.176.1 to 222.4.191.254222.4.191.2554,094
77222.4.192.0/20222.4.192.1 to 222.4.207.254222.4.207.2554,094
78222.4.208.0/20222.4.208.1 to 222.4.223.254222.4.223.2554,094
79222.4.224.0/20222.4.224.1 to 222.4.239.254222.4.239.2554,094
80222.4.240.0/20222.4.240.1 to 222.4.255.254222.4.255.2554,094
81222.5.0.0/20222.5.0.1 to 222.5.15.254222.5.15.2554,094
82222.5.16.0/20222.5.16.1 to 222.5.31.254222.5.31.2554,094
83222.5.32.0/20222.5.32.1 to 222.5.47.254222.5.47.2554,094
84222.5.48.0/20222.5.48.1 to 222.5.63.254222.5.63.2554,094
85222.5.64.0/20222.5.64.1 to 222.5.79.254222.5.79.2554,094
86222.5.80.0/20222.5.80.1 to 222.5.95.254222.5.95.2554,094
87222.5.96.0/20222.5.96.1 to 222.5.111.254222.5.111.2554,094
88222.5.112.0/20222.5.112.1 to 222.5.127.254222.5.127.2554,094
89222.5.128.0/20222.5.128.1 to 222.5.143.254222.5.143.2554,094
90222.5.144.0/20222.5.144.1 to 222.5.159.254222.5.159.2554,094
91222.5.160.0/20222.5.160.1 to 222.5.175.254222.5.175.2554,094
92222.5.176.0/20222.5.176.1 to 222.5.191.254222.5.191.2554,094
93222.5.192.0/20222.5.192.1 to 222.5.207.254222.5.207.2554,094
94222.5.208.0/20222.5.208.1 to 222.5.223.254222.5.223.2554,094
95222.5.224.0/20222.5.224.1 to 222.5.239.254222.5.239.2554,094
96222.5.240.0/20222.5.240.1 to 222.5.255.254222.5.255.2554,094
97222.6.0.0/20222.6.0.1 to 222.6.15.254222.6.15.2554,094
98222.6.16.0/20222.6.16.1 to 222.6.31.254222.6.31.2554,094
99222.6.32.0/20222.6.32.1 to 222.6.47.254222.6.47.2554,094
100222.6.48.0/20222.6.48.1 to 222.6.63.254222.6.63.2554,094
101222.6.64.0/20222.6.64.1 to 222.6.79.254222.6.79.2554,094
102222.6.80.0/20222.6.80.1 to 222.6.95.254222.6.95.2554,094
103222.6.96.0/20222.6.96.1 to 222.6.111.254222.6.111.2554,094
104222.6.112.0/20222.6.112.1 to 222.6.127.254222.6.127.2554,094
105222.6.128.0/20222.6.128.1 to 222.6.143.254222.6.143.2554,094
106222.6.144.0/20222.6.144.1 to 222.6.159.254222.6.159.2554,094
107222.6.160.0/20222.6.160.1 to 222.6.175.254222.6.175.2554,094
108222.6.176.0/20222.6.176.1 to 222.6.191.254222.6.191.2554,094
109222.6.192.0/20222.6.192.1 to 222.6.207.254222.6.207.2554,094
110222.6.208.0/20222.6.208.1 to 222.6.223.254222.6.223.2554,094
111222.6.224.0/20222.6.224.1 to 222.6.239.254222.6.239.2554,094
112222.6.240.0/20222.6.240.1 to 222.6.255.254222.6.255.2554,094
113222.7.0.0/20222.7.0.1 to 222.7.15.254222.7.15.2554,094
114222.7.16.0/20222.7.16.1 to 222.7.31.254222.7.31.2554,094
115222.7.32.0/20222.7.32.1 to 222.7.47.254222.7.47.2554,094
116222.7.48.0/20222.7.48.1 to 222.7.63.254222.7.63.2554,094
117222.7.64.0/20222.7.64.1 to 222.7.79.254222.7.79.2554,094
118222.7.80.0/20222.7.80.1 to 222.7.95.254222.7.95.2554,094
119222.7.96.0/20222.7.96.1 to 222.7.111.254222.7.111.2554,094
120222.7.112.0/20222.7.112.1 to 222.7.127.254222.7.127.2554,094
121222.7.128.0/20222.7.128.1 to 222.7.143.254222.7.143.2554,094
122222.7.144.0/20222.7.144.1 to 222.7.159.254222.7.159.2554,094
123222.7.160.0/20222.7.160.1 to 222.7.175.254222.7.175.2554,094
124222.7.176.0/20222.7.176.1 to 222.7.191.254222.7.191.2554,094
125222.7.192.0/20222.7.192.1 to 222.7.207.254222.7.207.2554,094
126222.7.208.0/20222.7.208.1 to 222.7.223.254222.7.223.2554,094
127222.7.224.0/20222.7.224.1 to 222.7.239.254222.7.239.2554,094
128222.7.240.0/20222.7.240.1 to 222.7.255.254222.7.255.2554,094
129222.8.0.0/20222.8.0.1 to 222.8.15.254222.8.15.2554,094
130222.8.16.0/20222.8.16.1 to 222.8.31.254222.8.31.2554,094
131222.8.32.0/20222.8.32.1 to 222.8.47.254222.8.47.2554,094
132222.8.48.0/20222.8.48.1 to 222.8.63.254222.8.63.2554,094
133222.8.64.0/20222.8.64.1 to 222.8.79.254222.8.79.2554,094
134222.8.80.0/20222.8.80.1 to 222.8.95.254222.8.95.2554,094
135222.8.96.0/20222.8.96.1 to 222.8.111.254222.8.111.2554,094
136222.8.112.0/20222.8.112.1 to 222.8.127.254222.8.127.2554,094
137222.8.128.0/20222.8.128.1 to 222.8.143.254222.8.143.2554,094
138222.8.144.0/20222.8.144.1 to 222.8.159.254222.8.159.2554,094
139222.8.160.0/20222.8.160.1 to 222.8.175.254222.8.175.2554,094
140222.8.176.0/20222.8.176.1 to 222.8.191.254222.8.191.2554,094
141222.8.192.0/20222.8.192.1 to 222.8.207.254222.8.207.2554,094
142222.8.208.0/20222.8.208.1 to 222.8.223.254222.8.223.2554,094
143222.8.224.0/20222.8.224.1 to 222.8.239.254222.8.239.2554,094
144222.8.240.0/20222.8.240.1 to 222.8.255.254222.8.255.2554,094
145222.9.0.0/20222.9.0.1 to 222.9.15.254222.9.15.2554,094
146222.9.16.0/20222.9.16.1 to 222.9.31.254222.9.31.2554,094
147222.9.32.0/20222.9.32.1 to 222.9.47.254222.9.47.2554,094
148222.9.48.0/20222.9.48.1 to 222.9.63.254222.9.63.2554,094
149222.9.64.0/20222.9.64.1 to 222.9.79.254222.9.79.2554,094
150222.9.80.0/20222.9.80.1 to 222.9.95.254222.9.95.2554,094
151222.9.96.0/20222.9.96.1 to 222.9.111.254222.9.111.2554,094
152222.9.112.0/20222.9.112.1 to 222.9.127.254222.9.127.2554,094
153222.9.128.0/20222.9.128.1 to 222.9.143.254222.9.143.2554,094
154222.9.144.0/20222.9.144.1 to 222.9.159.254222.9.159.2554,094
155222.9.160.0/20222.9.160.1 to 222.9.175.254222.9.175.2554,094
156222.9.176.0/20222.9.176.1 to 222.9.191.254222.9.191.2554,094
157222.9.192.0/20222.9.192.1 to 222.9.207.254222.9.207.2554,094
158222.9.208.0/20222.9.208.1 to 222.9.223.254222.9.223.2554,094
159222.9.224.0/20222.9.224.1 to 222.9.239.254222.9.239.2554,094
160222.9.240.0/20222.9.240.1 to 222.9.255.254222.9.255.2554,094
161222.10.0.0/20222.10.0.1 to 222.10.15.254222.10.15.2554,094
162222.10.16.0/20222.10.16.1 to 222.10.31.254222.10.31.2554,094
163222.10.32.0/20222.10.32.1 to 222.10.47.254222.10.47.2554,094
164222.10.48.0/20222.10.48.1 to 222.10.63.254222.10.63.2554,094
165222.10.64.0/20222.10.64.1 to 222.10.79.254222.10.79.2554,094
166222.10.80.0/20222.10.80.1 to 222.10.95.254222.10.95.2554,094
167222.10.96.0/20222.10.96.1 to 222.10.111.254222.10.111.2554,094
168222.10.112.0/20222.10.112.1 to 222.10.127.254222.10.127.2554,094
169222.10.128.0/20222.10.128.1 to 222.10.143.254222.10.143.2554,094
170222.10.144.0/20222.10.144.1 to 222.10.159.254222.10.159.2554,094
171222.10.160.0/20222.10.160.1 to 222.10.175.254222.10.175.2554,094
172222.10.176.0/20222.10.176.1 to 222.10.191.254222.10.191.2554,094
173222.10.192.0/20222.10.192.1 to 222.10.207.254222.10.207.2554,094
174222.10.208.0/20222.10.208.1 to 222.10.223.254222.10.223.2554,094
175222.10.224.0/20222.10.224.1 to 222.10.239.254222.10.239.2554,094
176222.10.240.0/20222.10.240.1 to 222.10.255.254222.10.255.2554,094
177222.11.0.0/20222.11.0.1 to 222.11.15.254222.11.15.2554,094
178222.11.16.0/20222.11.16.1 to 222.11.31.254222.11.31.2554,094
179222.11.32.0/20222.11.32.1 to 222.11.47.254222.11.47.2554,094
180222.11.48.0/20222.11.48.1 to 222.11.63.254222.11.63.2554,094
181222.11.64.0/20222.11.64.1 to 222.11.79.254222.11.79.2554,094
182222.11.80.0/20222.11.80.1 to 222.11.95.254222.11.95.2554,094
183222.11.96.0/20222.11.96.1 to 222.11.111.254222.11.111.2554,094
184222.11.112.0/20222.11.112.1 to 222.11.127.254222.11.127.2554,094
185222.11.128.0/20222.11.128.1 to 222.11.143.254222.11.143.2554,094
186222.11.144.0/20222.11.144.1 to 222.11.159.254222.11.159.2554,094
187222.11.160.0/20222.11.160.1 to 222.11.175.254222.11.175.2554,094
188222.11.176.0/20222.11.176.1 to 222.11.191.254222.11.191.2554,094
189222.11.192.0/20222.11.192.1 to 222.11.207.254222.11.207.2554,094
190222.11.208.0/20222.11.208.1 to 222.11.223.254222.11.223.2554,094
191222.11.224.0/20222.11.224.1 to 222.11.239.254222.11.239.2554,094
192222.11.240.0/20222.11.240.1 to 222.11.255.254222.11.255.2554,094
193222.12.0.0/20222.12.0.1 to 222.12.15.254222.12.15.2554,094
194222.12.16.0/20222.12.16.1 to 222.12.31.254222.12.31.2554,094
195222.12.32.0/20222.12.32.1 to 222.12.47.254222.12.47.2554,094
196222.12.48.0/20222.12.48.1 to 222.12.63.254222.12.63.2554,094
197222.12.64.0/20222.12.64.1 to 222.12.79.254222.12.79.2554,094
198222.12.80.0/20222.12.80.1 to 222.12.95.254222.12.95.2554,094
199222.12.96.0/20222.12.96.1 to 222.12.111.254222.12.111.2554,094
200222.12.112.0/20222.12.112.1 to 222.12.127.254222.12.127.2554,094
201222.12.128.0/20222.12.128.1 to 222.12.143.254222.12.143.2554,094
202222.12.144.0/20222.12.144.1 to 222.12.159.254222.12.159.2554,094
203222.12.160.0/20222.12.160.1 to 222.12.175.254222.12.175.2554,094
204222.12.176.0/20222.12.176.1 to 222.12.191.254222.12.191.2554,094
205222.12.192.0/20222.12.192.1 to 222.12.207.254222.12.207.2554,094
206222.12.208.0/20222.12.208.1 to 222.12.223.254222.12.223.2554,094
207222.12.224.0/20222.12.224.1 to 222.12.239.254222.12.239.2554,094
208222.12.240.0/20222.12.240.1 to 222.12.255.254222.12.255.2554,094
209222.13.0.0/20222.13.0.1 to 222.13.15.254222.13.15.2554,094
210222.13.16.0/20222.13.16.1 to 222.13.31.254222.13.31.2554,094
211222.13.32.0/20222.13.32.1 to 222.13.47.254222.13.47.2554,094
212222.13.48.0/20222.13.48.1 to 222.13.63.254222.13.63.2554,094
213222.13.64.0/20222.13.64.1 to 222.13.79.254222.13.79.2554,094
214222.13.80.0/20222.13.80.1 to 222.13.95.254222.13.95.2554,094
215222.13.96.0/20222.13.96.1 to 222.13.111.254222.13.111.2554,094
216222.13.112.0/20222.13.112.1 to 222.13.127.254222.13.127.2554,094
217222.13.128.0/20222.13.128.1 to 222.13.143.254222.13.143.2554,094
218222.13.144.0/20222.13.144.1 to 222.13.159.254222.13.159.2554,094
219222.13.160.0/20222.13.160.1 to 222.13.175.254222.13.175.2554,094
220222.13.176.0/20222.13.176.1 to 222.13.191.254222.13.191.2554,094
221222.13.192.0/20222.13.192.1 to 222.13.207.254222.13.207.2554,094
222222.13.208.0/20222.13.208.1 to 222.13.223.254222.13.223.2554,094
223222.13.224.0/20222.13.224.1 to 222.13.239.254222.13.239.2554,094
224222.13.240.0/20222.13.240.1 to 222.13.255.254222.13.255.2554,094
225222.14.0.0/20222.14.0.1 to 222.14.15.254222.14.15.2554,094
226222.14.16.0/20222.14.16.1 to 222.14.31.254222.14.31.2554,094
227222.14.32.0/20222.14.32.1 to 222.14.47.254222.14.47.2554,094
228222.14.48.0/20222.14.48.1 to 222.14.63.254222.14.63.2554,094
229222.14.64.0/20222.14.64.1 to 222.14.79.254222.14.79.2554,094
230222.14.80.0/20222.14.80.1 to 222.14.95.254222.14.95.2554,094
231222.14.96.0/20222.14.96.1 to 222.14.111.254222.14.111.2554,094
232222.14.112.0/20222.14.112.1 to 222.14.127.254222.14.127.2554,094
233222.14.128.0/20222.14.128.1 to 222.14.143.254222.14.143.2554,094
234222.14.144.0/20222.14.144.1 to 222.14.159.254222.14.159.2554,094
235222.14.160.0/20222.14.160.1 to 222.14.175.254222.14.175.2554,094
236222.14.176.0/20222.14.176.1 to 222.14.191.254222.14.191.2554,094
237222.14.192.0/20222.14.192.1 to 222.14.207.254222.14.207.2554,094
238222.14.208.0/20222.14.208.1 to 222.14.223.254222.14.223.2554,094
239222.14.224.0/20222.14.224.1 to 222.14.239.254222.14.239.2554,094
240222.14.240.0/20222.14.240.1 to 222.14.255.254222.14.255.2554,094
241222.15.0.0/20222.15.0.1 to 222.15.15.254222.15.15.2554,094
242222.15.16.0/20222.15.16.1 to 222.15.31.254222.15.31.2554,094
243222.15.32.0/20222.15.32.1 to 222.15.47.254222.15.47.2554,094
244222.15.48.0/20222.15.48.1 to 222.15.63.254222.15.63.2554,094
245222.15.64.0/20222.15.64.1 to 222.15.79.254222.15.79.2554,094
246222.15.80.0/20222.15.80.1 to 222.15.95.254222.15.95.2554,094
247222.15.96.0/20222.15.96.1 to 222.15.111.254222.15.111.2554,094
248222.15.112.0/20222.15.112.1 to 222.15.127.254222.15.127.2554,094
249222.15.128.0/20222.15.128.1 to 222.15.143.254222.15.143.2554,094
250222.15.144.0/20222.15.144.1 to 222.15.159.254222.15.159.2554,094
251222.15.160.0/20222.15.160.1 to 222.15.175.254222.15.175.2554,094
252222.15.176.0/20222.15.176.1 to 222.15.191.254222.15.191.2554,094
253222.15.192.0/20222.15.192.1 to 222.15.207.254222.15.207.2554,094
254222.15.208.0/20222.15.208.1 to 222.15.223.254222.15.223.2554,094
255222.15.224.0/20222.15.224.1 to 222.15.239.254222.15.239.2554,094
256222.15.240.0/20222.15.240.1 to 222.15.255.254222.15.255.2554,094

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.