Online Tone Generator — Test Frequencies

How to use

1. Pick a waveform. Choose Sine for a pure tone, the other shapes for harsher timbres, or White/Pink noise for a full-spectrum sound.
2. Set the frequency. Drag the slider or type an exact value in Hz. Start low and keep the volume modest. High frequencies can be piercing.
3. Play and route it. Hit Play, then send the output to both channels, left or right to test a specific speaker or your hearing in each ear.

Why test this

A pure, controllable tone is a measuring stick for everything audio. With one you can map the upper edge of your own hearing, a quick proxy for age-related hearing loss, by sweeping up until the sound vanishes. You can confirm whether a speaker or headphone actually reproduces the deep bass or sparkly highs it claims, since cheap drivers quietly roll off at the extremes. You can hunt down a rattle or a room resonance by parking a low frequency and listening for what buzzes. And pink noise, played through each speaker, is the classic way to check that a system sounds balanced rather than boomy or harsh. None of this needs an app or a signal generator on the bench. A browser oscillator is accurate enough for every practical check short of lab calibration.

What the results mean

A sine tone should sound smooth and pure at any frequency your gear and ears can handle. Sweep slowly upward at a modest volume and note where it fades to nothing. That number is roughly your hearing ceiling, and anything past the mid-teens of kHz is already good for an adult. At the low end, if a deep tone produces only a faint click or nothing at all, your speaker can't move enough air for that frequency, which is normal for laptop and phone speakers. Buzzing or rattling on a steady tone usually isn't the driver but something loose vibrating nearby, or a room mode at that frequency. With the harsher waveforms expect an edgy, harmonic-rich sound; if even a sine tone breaks up, you're clipping, so drop the volume. Use the left/right routing to compare your two ears or two speakers at the exact same frequency and level.

FAQ

What is a tone generator used for?

It produces a precise, steady frequency you can use to check the high-end limit of your hearing, test whether a speaker reproduces a given frequency, find a buzzing resonance in a room, or tune and calibrate audio gear.

What frequency range can I hear?

Healthy young ears reach roughly 20 Hz to 20 kHz. The upper limit drops with age, and many adults stop hearing above 15 to 17 kHz. Sweep upward at a modest volume and note where the tone disappears for you.

What's the difference between white and pink noise?

White noise has equal energy per frequency and sounds bright and hissy. Pink noise has equal energy per octave, sounds fuller and more balanced, and is the standard signal for checking speakers and room response.

Why does the tone sound distorted or harsh?

Square and sawtooth waves are rich in harmonics and sound buzzy by design. Real distortion at high volume usually means clipping, so lower the volume slider. A small speaker may also struggle with very low or very high frequencies.

Can a tone generator damage my speakers or hearing?

Sustained loud tones can stress small drivers and tire your ears, especially at high frequencies. Keep the volume low, avoid long bursts, and never crank an inaudible high tone you can't gauge by ear.

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