Online Tone Generator (20 Hz – 20 kHz)

How to use the tone generator

1. Drag the slider or type a value in the Frequency (Hz) box. The slider is logarithmic, so low and high frequencies are equally easy to reach.
2. Choose a waveform. Sine is a pure tone; square, triangle and sawtooth add harmonics and sound brighter or buzzier.
3. Press Play. While it plays you can keep moving the slider, nudge by ±1 Hz, or jump an octave up (×2) or down (÷2).
4. Use Balance to send the tone to the left or right speaker only.

What can you do with a frequency generator?

• Clean a speaker — 165 Hz is the classic water-ejection frequency. For a guided cycle, use the water eject sound.
• Test speakers and subwoofers — find where your bass rolls off or where a panel starts to buzz. Our bass test and sweep test automate this.
• Tune instruments — A4 = 440 Hz is concert pitch; middle C is 261.63 Hz.
• Check your hearing range — most adults stop hearing somewhere between 14 kHz and 17 kHz. Always do this at low volume.
• Find rattles and resonances in cars, rooms, desks and speaker cabinets by slowly moving through the low frequencies.
• Science and teaching — demonstrate pitch, octaves, beats and waveforms.

Useful frequencies at a glance

Frequency	What it is / what it’s used for
20–60 Hz	Sub-bass. Felt more than heard; tests subwoofers.
60–250 Hz	Bass. Kick drums, bass guitar. Phone speakers start here.
165 Hz	Popular water-eject / speaker-cleaning frequency.
261.63 Hz	Middle C (C4).
440 Hz	A4 — standard tuning pitch.
1,000 Hz	Standard test tone for audio levels.
2–5 kHz	Where human hearing is most sensitive. Keep volume low.
8–15 kHz	Treble, “air”, cymbals. Hearing-range checks.
17.4 kHz	The so-called “mosquito tone” that many adults cannot hear.

Safety: protect your ears and speakers

Pure tones can be fatiguing, and high frequencies are perceived as much louder than they look on a volume slider. Start quiet, avoid long exposure above 2 kHz, and never play high-volume tones through headphones. Small phone and laptop speakers cannot reproduce very low frequencies; pushing a 30 Hz tone at full volume just makes them buzz.

Does a “10000 Hz speaker cleaner sound” work?

Very high tones such as 10,000 Hz or 20,000 Hz move the speaker cone only a tiny distance, so they are poor at pushing out water. They can help shake loose very fine dust from the mesh, which is why our dust cleaner includes a short high-frequency stage. Tones marketed as “50,000 Hz” cannot be played by any phone speaker at all — the limit for normal audio is about 20 kHz.

Frequently asked questions

What is the best frequency to clean a speaker?

For water, around 165 Hz. For fine dust on the grille, a short burst of higher frequencies (4–12 kHz) helps. Our water eject tool combines both.

What is the highest frequency a human can hear?

Young people can hear up to about 20,000 Hz. With age the upper limit drops, and many adults cannot hear above 14–16 kHz.

Why can’t I hear low frequencies on my phone?

Phone and laptop speakers are tiny and physically cannot move enough air below roughly 100–200 Hz. Use headphones or a subwoofer to hear deep bass.

Is this tone generator free?

Yes, completely free with no app or sign-up. It uses the Web Audio API built into your browser.

Related free tools

• Frequency Sweep Test
• Bass & Subwoofer Test
• Speaker Test (Left/Right)
• Water Eject Sound
• Speaker Dust Cleaner