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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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Update checkIs this computer, phone and browser up to date? With links to update.Camera and mic testCheck your webcam and microphone before a call.Test print pagePrint an A4 page to check a printer: edges, text, line art and colours.

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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/16
Addresses2^112
/64 networks2^48
Network
ff6e::/16
First address
ff6e::
Last address
ff6e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
5,192,296,858,534,827,628,530,496,329,220,096 (2^112)
/64 networks (LANs)
281,474,976,710,656 (2^48)
Full form
ff6e:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
e.6.f.f.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

ff6e::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
1ff6e::/24ff6e:ff:ffff:ffff:ffff:ffff:ffff:ffff
2ff6e:100::/24ff6e:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3ff6e:200::/24ff6e:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4ff6e:300::/24ff6e:3ff:ffff:ffff:ffff:ffff:ffff:ffff
5ff6e:400::/24ff6e:4ff:ffff:ffff:ffff:ffff:ffff:ffff
6ff6e:500::/24ff6e:5ff:ffff:ffff:ffff:ffff:ffff:ffff
7ff6e:600::/24ff6e:6ff:ffff:ffff:ffff:ffff:ffff:ffff
8ff6e:700::/24ff6e:7ff:ffff:ffff:ffff:ffff:ffff:ffff
9ff6e:800::/24ff6e:8ff:ffff:ffff:ffff:ffff:ffff:ffff
10ff6e:900::/24ff6e:9ff:ffff:ffff:ffff:ffff:ffff:ffff
11ff6e:a00::/24ff6e:aff:ffff:ffff:ffff:ffff:ffff:ffff
12ff6e:b00::/24ff6e:bff:ffff:ffff:ffff:ffff:ffff:ffff
13ff6e:c00::/24ff6e:cff:ffff:ffff:ffff:ffff:ffff:ffff
14ff6e:d00::/24ff6e:dff:ffff:ffff:ffff:ffff:ffff:ffff
15ff6e:e00::/24ff6e:eff:ffff:ffff:ffff:ffff:ffff:ffff
16ff6e:f00::/24ff6e:fff:ffff:ffff:ffff:ffff:ffff:ffff
17ff6e:1000::/24ff6e:10ff:ffff:ffff:ffff:ffff:ffff:ffff
18ff6e:1100::/24ff6e:11ff:ffff:ffff:ffff:ffff:ffff:ffff
19ff6e:1200::/24ff6e:12ff:ffff:ffff:ffff:ffff:ffff:ffff
20ff6e:1300::/24ff6e:13ff:ffff:ffff:ffff:ffff:ffff:ffff
21ff6e:1400::/24ff6e:14ff:ffff:ffff:ffff:ffff:ffff:ffff
22ff6e:1500::/24ff6e:15ff:ffff:ffff:ffff:ffff:ffff:ffff
23ff6e:1600::/24ff6e:16ff:ffff:ffff:ffff:ffff:ffff:ffff
24ff6e:1700::/24ff6e:17ff:ffff:ffff:ffff:ffff:ffff:ffff
25ff6e:1800::/24ff6e:18ff:ffff:ffff:ffff:ffff:ffff:ffff
26ff6e:1900::/24ff6e:19ff:ffff:ffff:ffff:ffff:ffff:ffff
27ff6e:1a00::/24ff6e:1aff:ffff:ffff:ffff:ffff:ffff:ffff
28ff6e:1b00::/24ff6e:1bff:ffff:ffff:ffff:ffff:ffff:ffff
29ff6e:1c00::/24ff6e:1cff:ffff:ffff:ffff:ffff:ffff:ffff
30ff6e:1d00::/24ff6e:1dff:ffff:ffff:ffff:ffff:ffff:ffff
31ff6e:1e00::/24ff6e:1eff:ffff:ffff:ffff:ffff:ffff:ffff
32ff6e:1f00::/24ff6e:1fff:ffff:ffff:ffff:ffff:ffff:ffff
33ff6e:2000::/24ff6e:20ff:ffff:ffff:ffff:ffff:ffff:ffff
34ff6e:2100::/24ff6e:21ff:ffff:ffff:ffff:ffff:ffff:ffff
35ff6e:2200::/24ff6e:22ff:ffff:ffff:ffff:ffff:ffff:ffff
36ff6e:2300::/24ff6e:23ff:ffff:ffff:ffff:ffff:ffff:ffff
37ff6e:2400::/24ff6e:24ff:ffff:ffff:ffff:ffff:ffff:ffff
38ff6e:2500::/24ff6e:25ff:ffff:ffff:ffff:ffff:ffff:ffff
39ff6e:2600::/24ff6e:26ff:ffff:ffff:ffff:ffff:ffff:ffff
40ff6e:2700::/24ff6e:27ff:ffff:ffff:ffff:ffff:ffff:ffff
41ff6e:2800::/24ff6e:28ff:ffff:ffff:ffff:ffff:ffff:ffff
42ff6e:2900::/24ff6e:29ff:ffff:ffff:ffff:ffff:ffff:ffff
43ff6e:2a00::/24ff6e:2aff:ffff:ffff:ffff:ffff:ffff:ffff
44ff6e:2b00::/24ff6e:2bff:ffff:ffff:ffff:ffff:ffff:ffff
45ff6e:2c00::/24ff6e:2cff:ffff:ffff:ffff:ffff:ffff:ffff
46ff6e:2d00::/24ff6e:2dff:ffff:ffff:ffff:ffff:ffff:ffff
47ff6e:2e00::/24ff6e:2eff:ffff:ffff:ffff:ffff:ffff:ffff
48ff6e:2f00::/24ff6e:2fff:ffff:ffff:ffff:ffff:ffff:ffff
49ff6e:3000::/24ff6e:30ff:ffff:ffff:ffff:ffff:ffff:ffff
50ff6e:3100::/24ff6e:31ff:ffff:ffff:ffff:ffff:ffff:ffff
51ff6e:3200::/24ff6e:32ff:ffff:ffff:ffff:ffff:ffff:ffff
52ff6e:3300::/24ff6e:33ff:ffff:ffff:ffff:ffff:ffff:ffff
53ff6e:3400::/24ff6e:34ff:ffff:ffff:ffff:ffff:ffff:ffff
54ff6e:3500::/24ff6e:35ff:ffff:ffff:ffff:ffff:ffff:ffff
55ff6e:3600::/24ff6e:36ff:ffff:ffff:ffff:ffff:ffff:ffff
56ff6e:3700::/24ff6e:37ff:ffff:ffff:ffff:ffff:ffff:ffff
57ff6e:3800::/24ff6e:38ff:ffff:ffff:ffff:ffff:ffff:ffff
58ff6e:3900::/24ff6e:39ff:ffff:ffff:ffff:ffff:ffff:ffff
59ff6e:3a00::/24ff6e:3aff:ffff:ffff:ffff:ffff:ffff:ffff
60ff6e:3b00::/24ff6e:3bff:ffff:ffff:ffff:ffff:ffff:ffff
61ff6e:3c00::/24ff6e:3cff:ffff:ffff:ffff:ffff:ffff:ffff
62ff6e:3d00::/24ff6e:3dff:ffff:ffff:ffff:ffff:ffff:ffff
63ff6e:3e00::/24ff6e:3eff:ffff:ffff:ffff:ffff:ffff:ffff
64ff6e:3f00::/24ff6e:3fff:ffff:ffff:ffff:ffff:ffff:ffff
65ff6e:4000::/24ff6e:40ff:ffff:ffff:ffff:ffff:ffff:ffff
66ff6e:4100::/24ff6e:41ff:ffff:ffff:ffff:ffff:ffff:ffff
67ff6e:4200::/24ff6e:42ff:ffff:ffff:ffff:ffff:ffff:ffff
68ff6e:4300::/24ff6e:43ff:ffff:ffff:ffff:ffff:ffff:ffff
69ff6e:4400::/24ff6e:44ff:ffff:ffff:ffff:ffff:ffff:ffff
70ff6e:4500::/24ff6e:45ff:ffff:ffff:ffff:ffff:ffff:ffff
71ff6e:4600::/24ff6e:46ff:ffff:ffff:ffff:ffff:ffff:ffff
72ff6e:4700::/24ff6e:47ff:ffff:ffff:ffff:ffff:ffff:ffff
73ff6e:4800::/24ff6e:48ff:ffff:ffff:ffff:ffff:ffff:ffff
74ff6e:4900::/24ff6e:49ff:ffff:ffff:ffff:ffff:ffff:ffff
75ff6e:4a00::/24ff6e:4aff:ffff:ffff:ffff:ffff:ffff:ffff
76ff6e:4b00::/24ff6e:4bff:ffff:ffff:ffff:ffff:ffff:ffff
77ff6e:4c00::/24ff6e:4cff:ffff:ffff:ffff:ffff:ffff:ffff
78ff6e:4d00::/24ff6e:4dff:ffff:ffff:ffff:ffff:ffff:ffff
79ff6e:4e00::/24ff6e:4eff:ffff:ffff:ffff:ffff:ffff:ffff
80ff6e:4f00::/24ff6e:4fff:ffff:ffff:ffff:ffff:ffff:ffff
81ff6e:5000::/24ff6e:50ff:ffff:ffff:ffff:ffff:ffff:ffff
82ff6e:5100::/24ff6e:51ff:ffff:ffff:ffff:ffff:ffff:ffff
83ff6e:5200::/24ff6e:52ff:ffff:ffff:ffff:ffff:ffff:ffff
84ff6e:5300::/24ff6e:53ff:ffff:ffff:ffff:ffff:ffff:ffff
85ff6e:5400::/24ff6e:54ff:ffff:ffff:ffff:ffff:ffff:ffff
86ff6e:5500::/24ff6e:55ff:ffff:ffff:ffff:ffff:ffff:ffff
87ff6e:5600::/24ff6e:56ff:ffff:ffff:ffff:ffff:ffff:ffff
88ff6e:5700::/24ff6e:57ff:ffff:ffff:ffff:ffff:ffff:ffff
89ff6e:5800::/24ff6e:58ff:ffff:ffff:ffff:ffff:ffff:ffff
90ff6e:5900::/24ff6e:59ff:ffff:ffff:ffff:ffff:ffff:ffff
91ff6e:5a00::/24ff6e:5aff:ffff:ffff:ffff:ffff:ffff:ffff
92ff6e:5b00::/24ff6e:5bff:ffff:ffff:ffff:ffff:ffff:ffff
93ff6e:5c00::/24ff6e:5cff:ffff:ffff:ffff:ffff:ffff:ffff
94ff6e:5d00::/24ff6e:5dff:ffff:ffff:ffff:ffff:ffff:ffff
95ff6e:5e00::/24ff6e:5eff:ffff:ffff:ffff:ffff:ffff:ffff
96ff6e:5f00::/24ff6e:5fff:ffff:ffff:ffff:ffff:ffff:ffff
97ff6e:6000::/24ff6e:60ff:ffff:ffff:ffff:ffff:ffff:ffff
98ff6e:6100::/24ff6e:61ff:ffff:ffff:ffff:ffff:ffff:ffff
99ff6e:6200::/24ff6e:62ff:ffff:ffff:ffff:ffff:ffff:ffff
100ff6e:6300::/24ff6e:63ff:ffff:ffff:ffff:ffff:ffff:ffff
101ff6e:6400::/24ff6e:64ff:ffff:ffff:ffff:ffff:ffff:ffff
102ff6e:6500::/24ff6e:65ff:ffff:ffff:ffff:ffff:ffff:ffff
103ff6e:6600::/24ff6e:66ff:ffff:ffff:ffff:ffff:ffff:ffff
104ff6e:6700::/24ff6e:67ff:ffff:ffff:ffff:ffff:ffff:ffff
105ff6e:6800::/24ff6e:68ff:ffff:ffff:ffff:ffff:ffff:ffff
106ff6e:6900::/24ff6e:69ff:ffff:ffff:ffff:ffff:ffff:ffff
107ff6e:6a00::/24ff6e:6aff:ffff:ffff:ffff:ffff:ffff:ffff
108ff6e:6b00::/24ff6e:6bff:ffff:ffff:ffff:ffff:ffff:ffff
109ff6e:6c00::/24ff6e:6cff:ffff:ffff:ffff:ffff:ffff:ffff
110ff6e:6d00::/24ff6e:6dff:ffff:ffff:ffff:ffff:ffff:ffff
111ff6e:6e00::/24ff6e:6eff:ffff:ffff:ffff:ffff:ffff:ffff
112ff6e:6f00::/24ff6e:6fff:ffff:ffff:ffff:ffff:ffff:ffff
113ff6e:7000::/24ff6e:70ff:ffff:ffff:ffff:ffff:ffff:ffff
114ff6e:7100::/24ff6e:71ff:ffff:ffff:ffff:ffff:ffff:ffff
115ff6e:7200::/24ff6e:72ff:ffff:ffff:ffff:ffff:ffff:ffff
116ff6e:7300::/24ff6e:73ff:ffff:ffff:ffff:ffff:ffff:ffff
117ff6e:7400::/24ff6e:74ff:ffff:ffff:ffff:ffff:ffff:ffff
118ff6e:7500::/24ff6e:75ff:ffff:ffff:ffff:ffff:ffff:ffff
119ff6e:7600::/24ff6e:76ff:ffff:ffff:ffff:ffff:ffff:ffff
120ff6e:7700::/24ff6e:77ff:ffff:ffff:ffff:ffff:ffff:ffff
121ff6e:7800::/24ff6e:78ff:ffff:ffff:ffff:ffff:ffff:ffff
122ff6e:7900::/24ff6e:79ff:ffff:ffff:ffff:ffff:ffff:ffff
123ff6e:7a00::/24ff6e:7aff:ffff:ffff:ffff:ffff:ffff:ffff
124ff6e:7b00::/24ff6e:7bff:ffff:ffff:ffff:ffff:ffff:ffff
125ff6e:7c00::/24ff6e:7cff:ffff:ffff:ffff:ffff:ffff:ffff
126ff6e:7d00::/24ff6e:7dff:ffff:ffff:ffff:ffff:ffff:ffff
127ff6e:7e00::/24ff6e:7eff:ffff:ffff:ffff:ffff:ffff:ffff
128ff6e:7f00::/24ff6e:7fff:ffff:ffff:ffff:ffff:ffff:ffff
129ff6e:8000::/24ff6e:80ff:ffff:ffff:ffff:ffff:ffff:ffff
130ff6e:8100::/24ff6e:81ff:ffff:ffff:ffff:ffff:ffff:ffff
131ff6e:8200::/24ff6e:82ff:ffff:ffff:ffff:ffff:ffff:ffff
132ff6e:8300::/24ff6e:83ff:ffff:ffff:ffff:ffff:ffff:ffff
133ff6e:8400::/24ff6e:84ff:ffff:ffff:ffff:ffff:ffff:ffff
134ff6e:8500::/24ff6e:85ff:ffff:ffff:ffff:ffff:ffff:ffff
135ff6e:8600::/24ff6e:86ff:ffff:ffff:ffff:ffff:ffff:ffff
136ff6e:8700::/24ff6e:87ff:ffff:ffff:ffff:ffff:ffff:ffff
137ff6e:8800::/24ff6e:88ff:ffff:ffff:ffff:ffff:ffff:ffff
138ff6e:8900::/24ff6e:89ff:ffff:ffff:ffff:ffff:ffff:ffff
139ff6e:8a00::/24ff6e:8aff:ffff:ffff:ffff:ffff:ffff:ffff
140ff6e:8b00::/24ff6e:8bff:ffff:ffff:ffff:ffff:ffff:ffff
141ff6e:8c00::/24ff6e:8cff:ffff:ffff:ffff:ffff:ffff:ffff
142ff6e:8d00::/24ff6e:8dff:ffff:ffff:ffff:ffff:ffff:ffff
143ff6e:8e00::/24ff6e:8eff:ffff:ffff:ffff:ffff:ffff:ffff
144ff6e:8f00::/24ff6e:8fff:ffff:ffff:ffff:ffff:ffff:ffff
145ff6e:9000::/24ff6e:90ff:ffff:ffff:ffff:ffff:ffff:ffff
146ff6e:9100::/24ff6e:91ff:ffff:ffff:ffff:ffff:ffff:ffff
147ff6e:9200::/24ff6e:92ff:ffff:ffff:ffff:ffff:ffff:ffff
148ff6e:9300::/24ff6e:93ff:ffff:ffff:ffff:ffff:ffff:ffff
149ff6e:9400::/24ff6e:94ff:ffff:ffff:ffff:ffff:ffff:ffff
150ff6e:9500::/24ff6e:95ff:ffff:ffff:ffff:ffff:ffff:ffff
151ff6e:9600::/24ff6e:96ff:ffff:ffff:ffff:ffff:ffff:ffff
152ff6e:9700::/24ff6e:97ff:ffff:ffff:ffff:ffff:ffff:ffff
153ff6e:9800::/24ff6e:98ff:ffff:ffff:ffff:ffff:ffff:ffff
154ff6e:9900::/24ff6e:99ff:ffff:ffff:ffff:ffff:ffff:ffff
155ff6e:9a00::/24ff6e:9aff:ffff:ffff:ffff:ffff:ffff:ffff
156ff6e:9b00::/24ff6e:9bff:ffff:ffff:ffff:ffff:ffff:ffff
157ff6e:9c00::/24ff6e:9cff:ffff:ffff:ffff:ffff:ffff:ffff
158ff6e:9d00::/24ff6e:9dff:ffff:ffff:ffff:ffff:ffff:ffff
159ff6e:9e00::/24ff6e:9eff:ffff:ffff:ffff:ffff:ffff:ffff
160ff6e:9f00::/24ff6e:9fff:ffff:ffff:ffff:ffff:ffff:ffff
161ff6e:a000::/24ff6e:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
162ff6e:a100::/24ff6e:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
163ff6e:a200::/24ff6e:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
164ff6e:a300::/24ff6e:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
165ff6e:a400::/24ff6e:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
166ff6e:a500::/24ff6e:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
167ff6e:a600::/24ff6e:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
168ff6e:a700::/24ff6e:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
169ff6e:a800::/24ff6e:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
170ff6e:a900::/24ff6e:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
171ff6e:aa00::/24ff6e:aaff:ffff:ffff:ffff:ffff:ffff:ffff
172ff6e:ab00::/24ff6e:abff:ffff:ffff:ffff:ffff:ffff:ffff
173ff6e:ac00::/24ff6e:acff:ffff:ffff:ffff:ffff:ffff:ffff
174ff6e:ad00::/24ff6e:adff:ffff:ffff:ffff:ffff:ffff:ffff
175ff6e:ae00::/24ff6e:aeff:ffff:ffff:ffff:ffff:ffff:ffff
176ff6e:af00::/24ff6e:afff:ffff:ffff:ffff:ffff:ffff:ffff
177ff6e:b000::/24ff6e:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
178ff6e:b100::/24ff6e:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
179ff6e:b200::/24ff6e:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
180ff6e:b300::/24ff6e:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
181ff6e:b400::/24ff6e:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
182ff6e:b500::/24ff6e:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
183ff6e:b600::/24ff6e:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
184ff6e:b700::/24ff6e:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
185ff6e:b800::/24ff6e:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
186ff6e:b900::/24ff6e:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
187ff6e:ba00::/24ff6e:baff:ffff:ffff:ffff:ffff:ffff:ffff
188ff6e:bb00::/24ff6e:bbff:ffff:ffff:ffff:ffff:ffff:ffff
189ff6e:bc00::/24ff6e:bcff:ffff:ffff:ffff:ffff:ffff:ffff
190ff6e:bd00::/24ff6e:bdff:ffff:ffff:ffff:ffff:ffff:ffff
191ff6e:be00::/24ff6e:beff:ffff:ffff:ffff:ffff:ffff:ffff
192ff6e:bf00::/24ff6e:bfff:ffff:ffff:ffff:ffff:ffff:ffff
193ff6e:c000::/24ff6e:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
194ff6e:c100::/24ff6e:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
195ff6e:c200::/24ff6e:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
196ff6e:c300::/24ff6e:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
197ff6e:c400::/24ff6e:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
198ff6e:c500::/24ff6e:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
199ff6e:c600::/24ff6e:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
200ff6e:c700::/24ff6e:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
201ff6e:c800::/24ff6e:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
202ff6e:c900::/24ff6e:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
203ff6e:ca00::/24ff6e:caff:ffff:ffff:ffff:ffff:ffff:ffff
204ff6e:cb00::/24ff6e:cbff:ffff:ffff:ffff:ffff:ffff:ffff
205ff6e:cc00::/24ff6e:ccff:ffff:ffff:ffff:ffff:ffff:ffff
206ff6e:cd00::/24ff6e:cdff:ffff:ffff:ffff:ffff:ffff:ffff
207ff6e:ce00::/24ff6e:ceff:ffff:ffff:ffff:ffff:ffff:ffff
208ff6e:cf00::/24ff6e:cfff:ffff:ffff:ffff:ffff:ffff:ffff
209ff6e:d000::/24ff6e:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
210ff6e:d100::/24ff6e:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
211ff6e:d200::/24ff6e:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
212ff6e:d300::/24ff6e:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
213ff6e:d400::/24ff6e:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
214ff6e:d500::/24ff6e:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
215ff6e:d600::/24ff6e:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
216ff6e:d700::/24ff6e:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
217ff6e:d800::/24ff6e:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
218ff6e:d900::/24ff6e:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
219ff6e:da00::/24ff6e:daff:ffff:ffff:ffff:ffff:ffff:ffff
220ff6e:db00::/24ff6e:dbff:ffff:ffff:ffff:ffff:ffff:ffff
221ff6e:dc00::/24ff6e:dcff:ffff:ffff:ffff:ffff:ffff:ffff
222ff6e:dd00::/24ff6e:ddff:ffff:ffff:ffff:ffff:ffff:ffff
223ff6e:de00::/24ff6e:deff:ffff:ffff:ffff:ffff:ffff:ffff
224ff6e:df00::/24ff6e:dfff:ffff:ffff:ffff:ffff:ffff:ffff
225ff6e:e000::/24ff6e:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
226ff6e:e100::/24ff6e:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
227ff6e:e200::/24ff6e:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
228ff6e:e300::/24ff6e:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
229ff6e:e400::/24ff6e:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
230ff6e:e500::/24ff6e:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
231ff6e:e600::/24ff6e:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
232ff6e:e700::/24ff6e:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
233ff6e:e800::/24ff6e:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
234ff6e:e900::/24ff6e:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
235ff6e:ea00::/24ff6e:eaff:ffff:ffff:ffff:ffff:ffff:ffff
236ff6e:eb00::/24ff6e:ebff:ffff:ffff:ffff:ffff:ffff:ffff
237ff6e:ec00::/24ff6e:ecff:ffff:ffff:ffff:ffff:ffff:ffff
238ff6e:ed00::/24ff6e:edff:ffff:ffff:ffff:ffff:ffff:ffff
239ff6e:ee00::/24ff6e:eeff:ffff:ffff:ffff:ffff:ffff:ffff
240ff6e:ef00::/24ff6e:efff:ffff:ffff:ffff:ffff:ffff:ffff
241ff6e:f000::/24ff6e:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
242ff6e:f100::/24ff6e:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
243ff6e:f200::/24ff6e:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
244ff6e:f300::/24ff6e:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
245ff6e:f400::/24ff6e:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
246ff6e:f500::/24ff6e:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
247ff6e:f600::/24ff6e:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
248ff6e:f700::/24ff6e:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
249ff6e:f800::/24ff6e:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
250ff6e:f900::/24ff6e:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
251ff6e:fa00::/24ff6e:faff:ffff:ffff:ffff:ffff:ffff:ffff
252ff6e:fb00::/24ff6e:fbff:ffff:ffff:ffff:ffff:ffff:ffff
253ff6e:fc00::/24ff6e:fcff:ffff:ffff:ffff:ffff:ffff:ffff
254ff6e:fd00::/24ff6e:fdff:ffff:ffff:ffff:ffff:ffff:ffff
255ff6e:fe00::/24ff6e:feff:ffff:ffff:ffff:ffff:ffff:ffff
256ff6e:ff00::/24ff6e:ffff: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.