What you can use a tone generator for
- Testing speakers and headphones. Find where the bass fades out and listen for rattles and buzzing at certain frequencies.
- Tuning instruments. 440 Hz is the standard pitch for the note A above middle C. The note name updates as you change the frequency.
- Finding room problems. Sweep slowly through the low range to find boomy spots where the room makes some notes louder.
- Hearing range checks for fun. Most adults stop hearing somewhere between 14 and 17 kHz. This is not a medical hearing test.
Waveforms explained
| Wave | Sound | Good for |
|---|---|---|
| Sine | Pure, smooth tone with a single frequency | Speaker and hearing checks, tuning |
| Square | Hollow, buzzy, rich in odd harmonics | Old video game sounds, testing distortion |
| Triangle | Softer than square, slightly flute-like | Gentle test tones |
| Sawtooth | Bright and harsh, all harmonics | Synth sounds, testing high frequencies |
Protect your ears and speakers
Pure tones can sound quiet while carrying a lot of energy, especially at high and very low frequencies. Start with the system volume low and raise it slowly. Small speakers and tweeters can be damaged by long, loud tones, so keep tests short.
Frequently asked questions
Short answers to the questions people ask most about this test.
What frequency is middle C?
Middle C (C4) is about 261.6 Hz. The A above it (A4) is 440 Hz, the usual tuning pitch.
Why can I not hear the highest tones?
Most adults lose sensitivity at high frequencies with age. Many cannot hear above 15 or 16 kHz, which is normal. Some laptop speakers also stop well below 20 kHz.
Can I play a tone in only one ear?
Yes. Move the Left / right slider all the way to one side.
Does the tone generator work offline?
Yes. Once the page has loaded, the tone is created in your browser and needs no connection.