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Speed and call quality testTest delay, jitter and speed, with a focus on phone calls.My IP addressYour public IPv4 and IPv6 addresses, provider and address range.WhoIs lookupWho owns a domain or IP address, when it expires, and its DNS.DNS reportEvery DNS record for a domain, with email setup checked.IP subnet calculatorWork out a network's range, mask and hosts, and split it into subnets.

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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.

Prefix/20
Addresses2^108
/64 networks2^44
Network
ff0a:d000::/20
First address
ff0a:d000::
Last address
ff0a:dfff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
324,518,553,658,426,726,783,156,020,576,256 (2^108)
/64 networks (LANs)
17,592,186,044,416 (2^44)
Full form
ff0a:d000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
d.a.0.f.f.ip6.arpa
Split into smaller subnets/32
/21 (2)/22 (4)/23 (8)/24 (16)/28 (256)/32 (4,096)/36 (65,536)

ff0a:d000::/20 makes 4,096 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
1ff0a:d000::/32ff0a:d000:ffff:ffff:ffff:ffff:ffff:ffff
2ff0a:d001::/32ff0a:d001:ffff:ffff:ffff:ffff:ffff:ffff
3ff0a:d002::/32ff0a:d002:ffff:ffff:ffff:ffff:ffff:ffff
4ff0a:d003::/32ff0a:d003:ffff:ffff:ffff:ffff:ffff:ffff
5ff0a:d004::/32ff0a:d004:ffff:ffff:ffff:ffff:ffff:ffff
6ff0a:d005::/32ff0a:d005:ffff:ffff:ffff:ffff:ffff:ffff
7ff0a:d006::/32ff0a:d006:ffff:ffff:ffff:ffff:ffff:ffff
8ff0a:d007::/32ff0a:d007:ffff:ffff:ffff:ffff:ffff:ffff
9ff0a:d008::/32ff0a:d008:ffff:ffff:ffff:ffff:ffff:ffff
10ff0a:d009::/32ff0a:d009:ffff:ffff:ffff:ffff:ffff:ffff
11ff0a:d00a::/32ff0a:d00a:ffff:ffff:ffff:ffff:ffff:ffff
12ff0a:d00b::/32ff0a:d00b:ffff:ffff:ffff:ffff:ffff:ffff
13ff0a:d00c::/32ff0a:d00c:ffff:ffff:ffff:ffff:ffff:ffff
14ff0a:d00d::/32ff0a:d00d:ffff:ffff:ffff:ffff:ffff:ffff
15ff0a:d00e::/32ff0a:d00e:ffff:ffff:ffff:ffff:ffff:ffff
16ff0a:d00f::/32ff0a:d00f:ffff:ffff:ffff:ffff:ffff:ffff
17ff0a:d010::/32ff0a:d010:ffff:ffff:ffff:ffff:ffff:ffff
18ff0a:d011::/32ff0a:d011:ffff:ffff:ffff:ffff:ffff:ffff
19ff0a:d012::/32ff0a:d012:ffff:ffff:ffff:ffff:ffff:ffff
20ff0a:d013::/32ff0a:d013:ffff:ffff:ffff:ffff:ffff:ffff
21ff0a:d014::/32ff0a:d014:ffff:ffff:ffff:ffff:ffff:ffff
22ff0a:d015::/32ff0a:d015:ffff:ffff:ffff:ffff:ffff:ffff
23ff0a:d016::/32ff0a:d016:ffff:ffff:ffff:ffff:ffff:ffff
24ff0a:d017::/32ff0a:d017:ffff:ffff:ffff:ffff:ffff:ffff
25ff0a:d018::/32ff0a:d018:ffff:ffff:ffff:ffff:ffff:ffff
26ff0a:d019::/32ff0a:d019:ffff:ffff:ffff:ffff:ffff:ffff
27ff0a:d01a::/32ff0a:d01a:ffff:ffff:ffff:ffff:ffff:ffff
28ff0a:d01b::/32ff0a:d01b:ffff:ffff:ffff:ffff:ffff:ffff
29ff0a:d01c::/32ff0a:d01c:ffff:ffff:ffff:ffff:ffff:ffff
30ff0a:d01d::/32ff0a:d01d:ffff:ffff:ffff:ffff:ffff:ffff
31ff0a:d01e::/32ff0a:d01e:ffff:ffff:ffff:ffff:ffff:ffff
32ff0a:d01f::/32ff0a:d01f:ffff:ffff:ffff:ffff:ffff:ffff
33ff0a:d020::/32ff0a:d020:ffff:ffff:ffff:ffff:ffff:ffff
34ff0a:d021::/32ff0a:d021:ffff:ffff:ffff:ffff:ffff:ffff
35ff0a:d022::/32ff0a:d022:ffff:ffff:ffff:ffff:ffff:ffff
36ff0a:d023::/32ff0a:d023:ffff:ffff:ffff:ffff:ffff:ffff
37ff0a:d024::/32ff0a:d024:ffff:ffff:ffff:ffff:ffff:ffff
38ff0a:d025::/32ff0a:d025:ffff:ffff:ffff:ffff:ffff:ffff
39ff0a:d026::/32ff0a:d026:ffff:ffff:ffff:ffff:ffff:ffff
40ff0a:d027::/32ff0a:d027:ffff:ffff:ffff:ffff:ffff:ffff
41ff0a:d028::/32ff0a:d028:ffff:ffff:ffff:ffff:ffff:ffff
42ff0a:d029::/32ff0a:d029:ffff:ffff:ffff:ffff:ffff:ffff
43ff0a:d02a::/32ff0a:d02a:ffff:ffff:ffff:ffff:ffff:ffff
44ff0a:d02b::/32ff0a:d02b:ffff:ffff:ffff:ffff:ffff:ffff
45ff0a:d02c::/32ff0a:d02c:ffff:ffff:ffff:ffff:ffff:ffff
46ff0a:d02d::/32ff0a:d02d:ffff:ffff:ffff:ffff:ffff:ffff
47ff0a:d02e::/32ff0a:d02e:ffff:ffff:ffff:ffff:ffff:ffff
48ff0a:d02f::/32ff0a:d02f:ffff:ffff:ffff:ffff:ffff:ffff
49ff0a:d030::/32ff0a:d030:ffff:ffff:ffff:ffff:ffff:ffff
50ff0a:d031::/32ff0a:d031:ffff:ffff:ffff:ffff:ffff:ffff
51ff0a:d032::/32ff0a:d032:ffff:ffff:ffff:ffff:ffff:ffff
52ff0a:d033::/32ff0a:d033:ffff:ffff:ffff:ffff:ffff:ffff
53ff0a:d034::/32ff0a:d034:ffff:ffff:ffff:ffff:ffff:ffff
54ff0a:d035::/32ff0a:d035:ffff:ffff:ffff:ffff:ffff:ffff
55ff0a:d036::/32ff0a:d036:ffff:ffff:ffff:ffff:ffff:ffff
56ff0a:d037::/32ff0a:d037:ffff:ffff:ffff:ffff:ffff:ffff
57ff0a:d038::/32ff0a:d038:ffff:ffff:ffff:ffff:ffff:ffff
58ff0a:d039::/32ff0a:d039:ffff:ffff:ffff:ffff:ffff:ffff
59ff0a:d03a::/32ff0a:d03a:ffff:ffff:ffff:ffff:ffff:ffff
60ff0a:d03b::/32ff0a:d03b:ffff:ffff:ffff:ffff:ffff:ffff
61ff0a:d03c::/32ff0a:d03c:ffff:ffff:ffff:ffff:ffff:ffff
62ff0a:d03d::/32ff0a:d03d:ffff:ffff:ffff:ffff:ffff:ffff
63ff0a:d03e::/32ff0a:d03e:ffff:ffff:ffff:ffff:ffff:ffff
64ff0a:d03f::/32ff0a:d03f:ffff:ffff:ffff:ffff:ffff:ffff
65ff0a:d040::/32ff0a:d040:ffff:ffff:ffff:ffff:ffff:ffff
66ff0a:d041::/32ff0a:d041:ffff:ffff:ffff:ffff:ffff:ffff
67ff0a:d042::/32ff0a:d042:ffff:ffff:ffff:ffff:ffff:ffff
68ff0a:d043::/32ff0a:d043:ffff:ffff:ffff:ffff:ffff:ffff
69ff0a:d044::/32ff0a:d044:ffff:ffff:ffff:ffff:ffff:ffff
70ff0a:d045::/32ff0a:d045:ffff:ffff:ffff:ffff:ffff:ffff
71ff0a:d046::/32ff0a:d046:ffff:ffff:ffff:ffff:ffff:ffff
72ff0a:d047::/32ff0a:d047:ffff:ffff:ffff:ffff:ffff:ffff
73ff0a:d048::/32ff0a:d048:ffff:ffff:ffff:ffff:ffff:ffff
74ff0a:d049::/32ff0a:d049:ffff:ffff:ffff:ffff:ffff:ffff
75ff0a:d04a::/32ff0a:d04a:ffff:ffff:ffff:ffff:ffff:ffff
76ff0a:d04b::/32ff0a:d04b:ffff:ffff:ffff:ffff:ffff:ffff
77ff0a:d04c::/32ff0a:d04c:ffff:ffff:ffff:ffff:ffff:ffff
78ff0a:d04d::/32ff0a:d04d:ffff:ffff:ffff:ffff:ffff:ffff
79ff0a:d04e::/32ff0a:d04e:ffff:ffff:ffff:ffff:ffff:ffff
80ff0a:d04f::/32ff0a:d04f:ffff:ffff:ffff:ffff:ffff:ffff
81ff0a:d050::/32ff0a:d050:ffff:ffff:ffff:ffff:ffff:ffff
82ff0a:d051::/32ff0a:d051:ffff:ffff:ffff:ffff:ffff:ffff
83ff0a:d052::/32ff0a:d052:ffff:ffff:ffff:ffff:ffff:ffff
84ff0a:d053::/32ff0a:d053:ffff:ffff:ffff:ffff:ffff:ffff
85ff0a:d054::/32ff0a:d054:ffff:ffff:ffff:ffff:ffff:ffff
86ff0a:d055::/32ff0a:d055:ffff:ffff:ffff:ffff:ffff:ffff
87ff0a:d056::/32ff0a:d056:ffff:ffff:ffff:ffff:ffff:ffff
88ff0a:d057::/32ff0a:d057:ffff:ffff:ffff:ffff:ffff:ffff
89ff0a:d058::/32ff0a:d058:ffff:ffff:ffff:ffff:ffff:ffff
90ff0a:d059::/32ff0a:d059:ffff:ffff:ffff:ffff:ffff:ffff
91ff0a:d05a::/32ff0a:d05a:ffff:ffff:ffff:ffff:ffff:ffff
92ff0a:d05b::/32ff0a:d05b:ffff:ffff:ffff:ffff:ffff:ffff
93ff0a:d05c::/32ff0a:d05c:ffff:ffff:ffff:ffff:ffff:ffff
94ff0a:d05d::/32ff0a:d05d:ffff:ffff:ffff:ffff:ffff:ffff
95ff0a:d05e::/32ff0a:d05e:ffff:ffff:ffff:ffff:ffff:ffff
96ff0a:d05f::/32ff0a:d05f:ffff:ffff:ffff:ffff:ffff:ffff
97ff0a:d060::/32ff0a:d060:ffff:ffff:ffff:ffff:ffff:ffff
98ff0a:d061::/32ff0a:d061:ffff:ffff:ffff:ffff:ffff:ffff
99ff0a:d062::/32ff0a:d062:ffff:ffff:ffff:ffff:ffff:ffff
100ff0a:d063::/32ff0a:d063:ffff:ffff:ffff:ffff:ffff:ffff
101ff0a:d064::/32ff0a:d064:ffff:ffff:ffff:ffff:ffff:ffff
102ff0a:d065::/32ff0a:d065:ffff:ffff:ffff:ffff:ffff:ffff
103ff0a:d066::/32ff0a:d066:ffff:ffff:ffff:ffff:ffff:ffff
104ff0a:d067::/32ff0a:d067:ffff:ffff:ffff:ffff:ffff:ffff
105ff0a:d068::/32ff0a:d068:ffff:ffff:ffff:ffff:ffff:ffff
106ff0a:d069::/32ff0a:d069:ffff:ffff:ffff:ffff:ffff:ffff
107ff0a:d06a::/32ff0a:d06a:ffff:ffff:ffff:ffff:ffff:ffff
108ff0a:d06b::/32ff0a:d06b:ffff:ffff:ffff:ffff:ffff:ffff
109ff0a:d06c::/32ff0a:d06c:ffff:ffff:ffff:ffff:ffff:ffff
110ff0a:d06d::/32ff0a:d06d:ffff:ffff:ffff:ffff:ffff:ffff
111ff0a:d06e::/32ff0a:d06e:ffff:ffff:ffff:ffff:ffff:ffff
112ff0a:d06f::/32ff0a:d06f:ffff:ffff:ffff:ffff:ffff:ffff
113ff0a:d070::/32ff0a:d070:ffff:ffff:ffff:ffff:ffff:ffff
114ff0a:d071::/32ff0a:d071:ffff:ffff:ffff:ffff:ffff:ffff
115ff0a:d072::/32ff0a:d072:ffff:ffff:ffff:ffff:ffff:ffff
116ff0a:d073::/32ff0a:d073:ffff:ffff:ffff:ffff:ffff:ffff
117ff0a:d074::/32ff0a:d074:ffff:ffff:ffff:ffff:ffff:ffff
118ff0a:d075::/32ff0a:d075:ffff:ffff:ffff:ffff:ffff:ffff
119ff0a:d076::/32ff0a:d076:ffff:ffff:ffff:ffff:ffff:ffff
120ff0a:d077::/32ff0a:d077:ffff:ffff:ffff:ffff:ffff:ffff
121ff0a:d078::/32ff0a:d078:ffff:ffff:ffff:ffff:ffff:ffff
122ff0a:d079::/32ff0a:d079:ffff:ffff:ffff:ffff:ffff:ffff
123ff0a:d07a::/32ff0a:d07a:ffff:ffff:ffff:ffff:ffff:ffff
124ff0a:d07b::/32ff0a:d07b:ffff:ffff:ffff:ffff:ffff:ffff
125ff0a:d07c::/32ff0a:d07c:ffff:ffff:ffff:ffff:ffff:ffff
126ff0a:d07d::/32ff0a:d07d:ffff:ffff:ffff:ffff:ffff:ffff
127ff0a:d07e::/32ff0a:d07e:ffff:ffff:ffff:ffff:ffff:ffff
128ff0a:d07f::/32ff0a:d07f:ffff:ffff:ffff:ffff:ffff:ffff
129ff0a:d080::/32ff0a:d080:ffff:ffff:ffff:ffff:ffff:ffff
130ff0a:d081::/32ff0a:d081:ffff:ffff:ffff:ffff:ffff:ffff
131ff0a:d082::/32ff0a:d082:ffff:ffff:ffff:ffff:ffff:ffff
132ff0a:d083::/32ff0a:d083:ffff:ffff:ffff:ffff:ffff:ffff
133ff0a:d084::/32ff0a:d084:ffff:ffff:ffff:ffff:ffff:ffff
134ff0a:d085::/32ff0a:d085:ffff:ffff:ffff:ffff:ffff:ffff
135ff0a:d086::/32ff0a:d086:ffff:ffff:ffff:ffff:ffff:ffff
136ff0a:d087::/32ff0a:d087:ffff:ffff:ffff:ffff:ffff:ffff
137ff0a:d088::/32ff0a:d088:ffff:ffff:ffff:ffff:ffff:ffff
138ff0a:d089::/32ff0a:d089:ffff:ffff:ffff:ffff:ffff:ffff
139ff0a:d08a::/32ff0a:d08a:ffff:ffff:ffff:ffff:ffff:ffff
140ff0a:d08b::/32ff0a:d08b:ffff:ffff:ffff:ffff:ffff:ffff
141ff0a:d08c::/32ff0a:d08c:ffff:ffff:ffff:ffff:ffff:ffff
142ff0a:d08d::/32ff0a:d08d:ffff:ffff:ffff:ffff:ffff:ffff
143ff0a:d08e::/32ff0a:d08e:ffff:ffff:ffff:ffff:ffff:ffff
144ff0a:d08f::/32ff0a:d08f:ffff:ffff:ffff:ffff:ffff:ffff
145ff0a:d090::/32ff0a:d090:ffff:ffff:ffff:ffff:ffff:ffff
146ff0a:d091::/32ff0a:d091:ffff:ffff:ffff:ffff:ffff:ffff
147ff0a:d092::/32ff0a:d092:ffff:ffff:ffff:ffff:ffff:ffff
148ff0a:d093::/32ff0a:d093:ffff:ffff:ffff:ffff:ffff:ffff
149ff0a:d094::/32ff0a:d094:ffff:ffff:ffff:ffff:ffff:ffff
150ff0a:d095::/32ff0a:d095:ffff:ffff:ffff:ffff:ffff:ffff
151ff0a:d096::/32ff0a:d096:ffff:ffff:ffff:ffff:ffff:ffff
152ff0a:d097::/32ff0a:d097:ffff:ffff:ffff:ffff:ffff:ffff
153ff0a:d098::/32ff0a:d098:ffff:ffff:ffff:ffff:ffff:ffff
154ff0a:d099::/32ff0a:d099:ffff:ffff:ffff:ffff:ffff:ffff
155ff0a:d09a::/32ff0a:d09a:ffff:ffff:ffff:ffff:ffff:ffff
156ff0a:d09b::/32ff0a:d09b:ffff:ffff:ffff:ffff:ffff:ffff
157ff0a:d09c::/32ff0a:d09c:ffff:ffff:ffff:ffff:ffff:ffff
158ff0a:d09d::/32ff0a:d09d:ffff:ffff:ffff:ffff:ffff:ffff
159ff0a:d09e::/32ff0a:d09e:ffff:ffff:ffff:ffff:ffff:ffff
160ff0a:d09f::/32ff0a:d09f:ffff:ffff:ffff:ffff:ffff:ffff
161ff0a:d0a0::/32ff0a:d0a0:ffff:ffff:ffff:ffff:ffff:ffff
162ff0a:d0a1::/32ff0a:d0a1:ffff:ffff:ffff:ffff:ffff:ffff
163ff0a:d0a2::/32ff0a:d0a2:ffff:ffff:ffff:ffff:ffff:ffff
164ff0a:d0a3::/32ff0a:d0a3:ffff:ffff:ffff:ffff:ffff:ffff
165ff0a:d0a4::/32ff0a:d0a4:ffff:ffff:ffff:ffff:ffff:ffff
166ff0a:d0a5::/32ff0a:d0a5:ffff:ffff:ffff:ffff:ffff:ffff
167ff0a:d0a6::/32ff0a:d0a6:ffff:ffff:ffff:ffff:ffff:ffff
168ff0a:d0a7::/32ff0a:d0a7:ffff:ffff:ffff:ffff:ffff:ffff
169ff0a:d0a8::/32ff0a:d0a8:ffff:ffff:ffff:ffff:ffff:ffff
170ff0a:d0a9::/32ff0a:d0a9:ffff:ffff:ffff:ffff:ffff:ffff
171ff0a:d0aa::/32ff0a:d0aa:ffff:ffff:ffff:ffff:ffff:ffff
172ff0a:d0ab::/32ff0a:d0ab:ffff:ffff:ffff:ffff:ffff:ffff
173ff0a:d0ac::/32ff0a:d0ac:ffff:ffff:ffff:ffff:ffff:ffff
174ff0a:d0ad::/32ff0a:d0ad:ffff:ffff:ffff:ffff:ffff:ffff
175ff0a:d0ae::/32ff0a:d0ae:ffff:ffff:ffff:ffff:ffff:ffff
176ff0a:d0af::/32ff0a:d0af:ffff:ffff:ffff:ffff:ffff:ffff
177ff0a:d0b0::/32ff0a:d0b0:ffff:ffff:ffff:ffff:ffff:ffff
178ff0a:d0b1::/32ff0a:d0b1:ffff:ffff:ffff:ffff:ffff:ffff
179ff0a:d0b2::/32ff0a:d0b2:ffff:ffff:ffff:ffff:ffff:ffff
180ff0a:d0b3::/32ff0a:d0b3:ffff:ffff:ffff:ffff:ffff:ffff
181ff0a:d0b4::/32ff0a:d0b4:ffff:ffff:ffff:ffff:ffff:ffff
182ff0a:d0b5::/32ff0a:d0b5:ffff:ffff:ffff:ffff:ffff:ffff
183ff0a:d0b6::/32ff0a:d0b6:ffff:ffff:ffff:ffff:ffff:ffff
184ff0a:d0b7::/32ff0a:d0b7:ffff:ffff:ffff:ffff:ffff:ffff
185ff0a:d0b8::/32ff0a:d0b8:ffff:ffff:ffff:ffff:ffff:ffff
186ff0a:d0b9::/32ff0a:d0b9:ffff:ffff:ffff:ffff:ffff:ffff
187ff0a:d0ba::/32ff0a:d0ba:ffff:ffff:ffff:ffff:ffff:ffff
188ff0a:d0bb::/32ff0a:d0bb:ffff:ffff:ffff:ffff:ffff:ffff
189ff0a:d0bc::/32ff0a:d0bc:ffff:ffff:ffff:ffff:ffff:ffff
190ff0a:d0bd::/32ff0a:d0bd:ffff:ffff:ffff:ffff:ffff:ffff
191ff0a:d0be::/32ff0a:d0be:ffff:ffff:ffff:ffff:ffff:ffff
192ff0a:d0bf::/32ff0a:d0bf:ffff:ffff:ffff:ffff:ffff:ffff
193ff0a:d0c0::/32ff0a:d0c0:ffff:ffff:ffff:ffff:ffff:ffff
194ff0a:d0c1::/32ff0a:d0c1:ffff:ffff:ffff:ffff:ffff:ffff
195ff0a:d0c2::/32ff0a:d0c2:ffff:ffff:ffff:ffff:ffff:ffff
196ff0a:d0c3::/32ff0a:d0c3:ffff:ffff:ffff:ffff:ffff:ffff
197ff0a:d0c4::/32ff0a:d0c4:ffff:ffff:ffff:ffff:ffff:ffff
198ff0a:d0c5::/32ff0a:d0c5:ffff:ffff:ffff:ffff:ffff:ffff
199ff0a:d0c6::/32ff0a:d0c6:ffff:ffff:ffff:ffff:ffff:ffff
200ff0a:d0c7::/32ff0a:d0c7:ffff:ffff:ffff:ffff:ffff:ffff
201ff0a:d0c8::/32ff0a:d0c8:ffff:ffff:ffff:ffff:ffff:ffff
202ff0a:d0c9::/32ff0a:d0c9:ffff:ffff:ffff:ffff:ffff:ffff
203ff0a:d0ca::/32ff0a:d0ca:ffff:ffff:ffff:ffff:ffff:ffff
204ff0a:d0cb::/32ff0a:d0cb:ffff:ffff:ffff:ffff:ffff:ffff
205ff0a:d0cc::/32ff0a:d0cc:ffff:ffff:ffff:ffff:ffff:ffff
206ff0a:d0cd::/32ff0a:d0cd:ffff:ffff:ffff:ffff:ffff:ffff
207ff0a:d0ce::/32ff0a:d0ce:ffff:ffff:ffff:ffff:ffff:ffff
208ff0a:d0cf::/32ff0a:d0cf:ffff:ffff:ffff:ffff:ffff:ffff
209ff0a:d0d0::/32ff0a:d0d0:ffff:ffff:ffff:ffff:ffff:ffff
210ff0a:d0d1::/32ff0a:d0d1:ffff:ffff:ffff:ffff:ffff:ffff
211ff0a:d0d2::/32ff0a:d0d2:ffff:ffff:ffff:ffff:ffff:ffff
212ff0a:d0d3::/32ff0a:d0d3:ffff:ffff:ffff:ffff:ffff:ffff
213ff0a:d0d4::/32ff0a:d0d4:ffff:ffff:ffff:ffff:ffff:ffff
214ff0a:d0d5::/32ff0a:d0d5:ffff:ffff:ffff:ffff:ffff:ffff
215ff0a:d0d6::/32ff0a:d0d6:ffff:ffff:ffff:ffff:ffff:ffff
216ff0a:d0d7::/32ff0a:d0d7:ffff:ffff:ffff:ffff:ffff:ffff
217ff0a:d0d8::/32ff0a:d0d8:ffff:ffff:ffff:ffff:ffff:ffff
218ff0a:d0d9::/32ff0a:d0d9:ffff:ffff:ffff:ffff:ffff:ffff
219ff0a:d0da::/32ff0a:d0da:ffff:ffff:ffff:ffff:ffff:ffff
220ff0a:d0db::/32ff0a:d0db:ffff:ffff:ffff:ffff:ffff:ffff
221ff0a:d0dc::/32ff0a:d0dc:ffff:ffff:ffff:ffff:ffff:ffff
222ff0a:d0dd::/32ff0a:d0dd:ffff:ffff:ffff:ffff:ffff:ffff
223ff0a:d0de::/32ff0a:d0de:ffff:ffff:ffff:ffff:ffff:ffff
224ff0a:d0df::/32ff0a:d0df:ffff:ffff:ffff:ffff:ffff:ffff
225ff0a:d0e0::/32ff0a:d0e0:ffff:ffff:ffff:ffff:ffff:ffff
226ff0a:d0e1::/32ff0a:d0e1:ffff:ffff:ffff:ffff:ffff:ffff
227ff0a:d0e2::/32ff0a:d0e2:ffff:ffff:ffff:ffff:ffff:ffff
228ff0a:d0e3::/32ff0a:d0e3:ffff:ffff:ffff:ffff:ffff:ffff
229ff0a:d0e4::/32ff0a:d0e4:ffff:ffff:ffff:ffff:ffff:ffff
230ff0a:d0e5::/32ff0a:d0e5:ffff:ffff:ffff:ffff:ffff:ffff
231ff0a:d0e6::/32ff0a:d0e6:ffff:ffff:ffff:ffff:ffff:ffff
232ff0a:d0e7::/32ff0a:d0e7:ffff:ffff:ffff:ffff:ffff:ffff
233ff0a:d0e8::/32ff0a:d0e8:ffff:ffff:ffff:ffff:ffff:ffff
234ff0a:d0e9::/32ff0a:d0e9:ffff:ffff:ffff:ffff:ffff:ffff
235ff0a:d0ea::/32ff0a:d0ea:ffff:ffff:ffff:ffff:ffff:ffff
236ff0a:d0eb::/32ff0a:d0eb:ffff:ffff:ffff:ffff:ffff:ffff
237ff0a:d0ec::/32ff0a:d0ec:ffff:ffff:ffff:ffff:ffff:ffff
238ff0a:d0ed::/32ff0a:d0ed:ffff:ffff:ffff:ffff:ffff:ffff
239ff0a:d0ee::/32ff0a:d0ee:ffff:ffff:ffff:ffff:ffff:ffff
240ff0a:d0ef::/32ff0a:d0ef:ffff:ffff:ffff:ffff:ffff:ffff
241ff0a:d0f0::/32ff0a:d0f0:ffff:ffff:ffff:ffff:ffff:ffff
242ff0a:d0f1::/32ff0a:d0f1:ffff:ffff:ffff:ffff:ffff:ffff
243ff0a:d0f2::/32ff0a:d0f2:ffff:ffff:ffff:ffff:ffff:ffff
244ff0a:d0f3::/32ff0a:d0f3:ffff:ffff:ffff:ffff:ffff:ffff
245ff0a:d0f4::/32ff0a:d0f4:ffff:ffff:ffff:ffff:ffff:ffff
246ff0a:d0f5::/32ff0a:d0f5:ffff:ffff:ffff:ffff:ffff:ffff
247ff0a:d0f6::/32ff0a:d0f6:ffff:ffff:ffff:ffff:ffff:ffff
248ff0a:d0f7::/32ff0a:d0f7:ffff:ffff:ffff:ffff:ffff:ffff
249ff0a:d0f8::/32ff0a:d0f8:ffff:ffff:ffff:ffff:ffff:ffff
250ff0a:d0f9::/32ff0a:d0f9:ffff:ffff:ffff:ffff:ffff:ffff
251ff0a:d0fa::/32ff0a:d0fa:ffff:ffff:ffff:ffff:ffff:ffff
252ff0a:d0fb::/32ff0a:d0fb:ffff:ffff:ffff:ffff:ffff:ffff
253ff0a:d0fc::/32ff0a:d0fc:ffff:ffff:ffff:ffff:ffff:ffff
254ff0a:d0fd::/32ff0a:d0fd:ffff:ffff:ffff:ffff:ffff:ffff
255ff0a:d0fe::/32ff0a:d0fe:ffff:ffff:ffff:ffff:ffff:ffff
256ff0a:d0ff::/32ff0a:d0ff:ffff:ffff:ffff:ffff:ffff:ffff

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.