20 Hz to 20 kHz tone generator
Frequency Test
Use an online tone generator for exact frequencies, practical presets, or a 20 Hz to 20 kHz audio sweep.
Start at low volume. No audio leaves your device.
20 Hz - 20 kHz generator
ReadyKeep volume low, especially below 60 Hz and above 10 kHz. Stop immediately if you feel discomfort.
How to use the frequency tone generator
Use the midrange preset at low volume to confirm comfortable playback.
Enter a frequency or use the slider without making sudden volume changes.
Note repeatable buzzes or dropouts and retest them with a fixed tone.
This frequency test generates a sine wave from 20 Hz to 20 kHz inside your browser. Enter an exact number, move the slider, choose a preset, or run the automatic sweep. The fixed tone continues until you press Stop, making it useful for locating a repeatable rattle or comparing the same frequency across two devices.
A sine wave contains one fundamental frequency without the harmonics found in most instruments. That makes problems easier to isolate, but it also concentrates energy. Keep system volume low and use short sessions. Very low frequencies can demand large driver movement, while high frequencies can feel uncomfortable before they seem loud.
Use fixed tones for targeted checks
Start at 440 Hz because most audio systems reproduce this midrange region comfortably. Once level is set, change the number gradually. A 100 Hz preset is useful for basic bass behavior, and 1 kHz is a common midrange reference. The tool updates a playing oscillator smoothly so changing frequency does not require restarting playback.
If you hear a buzz at one value, stop the tone and repeat it at a lower volume. Move loose objects away from speakers and check whether the sound comes from a driver, cabinet, desk, or nearby item. A room object can resonate at a narrow frequency even when the speaker is working correctly.
Understand the automatic sweep
The eight-second sweep rises exponentially from 20 Hz to 20 kHz. Exponential movement gives each octave a more useful share of time than a simple linear sweep. Listen for sudden discontinuities, rattles, or one channel dropping out. Do not expect equal perceived loudness across the range.
Hearing sensitivity changes with frequency, and every transducer has its own response. Rooms create strong peaks and cancellations at bass frequencies. Bluetooth codecs, equalizers, hearing protection features, and volume normalization can also influence the result. A smooth-sounding sweep is encouraging, but it is not a calibrated response measurement.
Limits of an online tone generator
The Web Audio API schedules the oscillator accurately enough for practical listening checks. The browser then passes it through the operating system, sound device, amplifier, and transducer. Any stage can resample, filter, limit, or enhance the output. Use dedicated calibrated hardware when a test requires traceable frequency or level accuracy.
Do not use the upper limit as a competition or hearing diagnosis. Many adults do not hear 18 or 20 kHz, and many products do not reproduce those tones strongly. Never increase the volume sharply at an inaudible frequency. For guided hardware checks, use the headphone or speaker page, which limits each tone to a short, task-specific interval.