Device Bench

Device test · Audio

Tone Generator

Pick a frequency from 20 Hz to 20 kHz and press play.

Hz440 Wavesine Vol20% Statusidle
Hz · log scale
Waveform

Sustained pure tones can damage hearing. Start at a low volume and raise it gradually, especially with headphones or earbuds, and turn it down before changing waveforms: square and sawtooth waves can sound much louder than a sine at the same setting. With the volume slider at 100 the tone leaves this page at −6 dBFS, half of digital full scale. That is a ceiling on the signal, not a safe listening level, and your device's volume control decides how loud it gets from there.

How this test works

Set a frequency, then press Play tone to play it as a continuous sine, square, triangle, or sawtooth wave. A steady tone holds one point of the spectrum still, so you can hear where a speaker fades out at the bottom of its range, where a cabinet or desk starts to rattle, or whether the left and right drivers sound the same. You can change any setting while the tone plays, and Stop tone fades it out. Setting Volume to zero mutes the tone without stopping it, so the status stays playing. Your settings stay in place when you stop.

The tone comes from the Web Audio API's oscillator, running at your browser's audio sample rate, typically 44.1 or 48 kHz. The frequency slider is logarithmic, like pitch perception: equal movements multiply the frequency, so each octave gets the same travel. Type into the number field to set a frequency directly; values outside 20 Hz to 20 kHz are clamped to that range. The readout rounds to the nearest hertz, while the oscillator gets the exact value. Starting and stopping use a gain ramp of roughly 20 milliseconds, and frequency and volume changes are smoothed too, because a sudden jump in the waveform makes a click that has nothing to do with your equipment. Waveform changes apply at once. The Volume slider follows a squared curve up to the −6 dBFS ceiling, so 50% gives a quarter of the top level.

The page does not listen to its own output, so a playing status cannot tell you whether you hear anything. Your browser, output device, connection, and speakers or headphones decide what reaches you, especially at the very low and very high ends. At the top of the range, inexpensive converters and Bluetooth codecs can add artifacts that the oscillator did not produce. Because the output level is uncalibrated, this generator cannot measure loudness, frequency response, or anything about your hearing.

Frequently asked questions

What frequencies should I use to check speakers or a subwoofer?
Start with the default 440 Hz sine tone at a low volume, then work through the range in stages. Most full-size speakers hold output down to somewhere between 50 and 80 Hz, and dedicated subwoofers reach 30 Hz or lower, so sweep the low end slowly and note where the tone fades. Around 500–2,000 Hz, listen for buzzes and cabinet rattles, which show up clearly on a steady tone. Then step through 8–15 kHz to check that the tweeter stays clean. Stop the tone if you hear distortion.
Why can square and sawtooth waves sound louder than a sine?
A sine wave puts all of its energy at the one frequency you set. Square and sawtooth waves add a stack of harmonics above it, which makes them sound louder and harsher than a sine at the same Volume setting. Turn the volume down before switching waveforms, not after.
I hear nothing at some frequencies. Is my speaker broken?
Usually not. First check that the status says playing, Volume is above zero, neither the tab nor the device is muted, and the right output device is selected. If all of that is fine, you have most likely reached the edge of what your speakers or headphones reproduce: small speakers often give nothing usable below about 80 Hz, and many devices fade well before 20 kHz. Try the same frequency on a second device or on wired headphones instead of turning the volume up. If only one device goes quiet at a frequency the other plays, that difference is worth looking into.
Is this a hearing test?
No. This page is not a hearing test and cannot be used as one. Its output level is uncalibrated, and how far into the high frequencies anyone hears varies with age, equipment and volume, so it cannot diagnose hearing loss or any other condition. Nothing you do or do not hear here carries medical meaning. A real hearing assessment uses calibrated equipment administered by a qualified professional.
Can a continuous tone damage my speakers or headphones?
Yes, if it is loud and sustained. A continuous tone has none of music's quiet passages, so it heats a driver's voice coil steadily, and loud deep bass can push a small speaker's cone past its limits. At moderate volume, drivers handle steady signals fine. Keep both this page's Volume and your device's volume low, keep checks brief, and stop immediately if you hear distortion, buzzing, or flapping.

Related tools