Welcome to the World Tone Database, dedicated to the A-Z of international call progress tones. From here you can research tone parameters in national tone plans and hear the tones on-line.
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| Country | Tone | Frequency/Hz | Cadence/s | Audio |
| Hong Kong | Busy tone | 480+620 | 0.5 on 0.5 off |  |
| Hong Kong | Congestion tone | 480+620 | 0.25 on 0.25 off | |
| Hong Kong | Dial tone | 350+440 | continuous | |
| Hong Kong | Disconnect tone | |||
| Hong Kong | Number unobtainable tone | |||
| Hong Kong | Ringing tone | |||
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