Tone Generator
Pick any frequency and waveform and play it instantly — for testing speakers, hearing or tuning.
How to use
- 1Start with low volume, especially on headphones.
- 2Drag the slider or type a frequency between 20 and 20,000 Hz.
- 3Choose a waveform.
- 4Tap Play. Adjust frequency while it plays; tap Stop to finish.
What a tone generator is used for
- Checking the frequency range of speakers and headphones.
- Finding rattles or buzzes in a speaker, car door or room.
- Rough hearing range checks (not a medical test).
- Tuning instruments to a reference pitch like 440 Hz.
- Science classes and audio experiments.
Waveforms explained
Sine
A pure tone with a single frequency. Best for speaker and hearing checks.
Square
Buzzy and rich in odd harmonics. Sounds louder at the same volume.
Sawtooth
Bright and harsh, containing all harmonics. Common in synthesisers.
Triangle
Softer than square, with weaker harmonics. Sounds like a muted flute.
Protect your ears and speakers
High frequencies can be uncomfortable even when they seem quiet, and some people can't hear them at all, which makes it easy to turn the volume too high. Start low and increase slowly. Avoid long sessions with very loud tones, and don't play extreme low frequencies at full volume on small speakers.
Why some frequencies are silent
Phone speakers rarely reproduce much below 150–200 Hz, and many adults can't hear above 14–16 kHz. If a tone seems silent, try headphones or a different speaker before assuming something is broken.
Helpful products
Affiliate links — we may earn a commission.
- Wired over-ear headphones
Wired headphones avoid Bluetooth compression when testing tones.
- Clip-on instrument tuner
A dedicated tuner is handier for regular instrument tuning.
Frequently asked questions
What frequency range can humans hear?
Roughly 20 Hz to 20 kHz for young people, with the upper limit dropping with age.
Is this a hearing test?
No. It can give a rough idea, but only an audiologist can test your hearing properly.
Why does square wave sound louder?
It contains extra harmonics, so it carries more energy at the same peak level.
What is 440 Hz?
The standard tuning pitch for the A above middle C.
Can I damage my speaker?
Very loud low tones over long periods can stress small speakers. Use moderate volume.
Does it work in the background?
Browsers may pause audio when the screen locks or the tab is hidden.
Related tools
Speaker & Stereo Test
Play sound from the left, right or both speakers and check frequency response.
Speaker Cleaner (Water Eject)
Play low tones that help push small water droplets out of your speaker grille.
Microphone Test
Check your mic with a live waveform, level meter and 5-second recording.