Tone generator · 20 Hz – 20 kHz
Tone generator.
Play any frequency from 20 Hz to 20 kHz. The generator knows your A4, so it shows the note and the cents for every pitch.
Tone generator
Any pitch, any A.
A4 0.0 ¢ at A = 440
Start quiet: high tones and square waves tire your ears fast.
Keys: Space play or stop · ← → half step · ↑ ↓ 1 Hz (Shift: 0.1 Hz)
Reference pitch
Reference A
Slider 380–500 Hz. Type any value from 300 to 600 Hz. The tuner uses the same A.
Note names
Notes and cents
A tone generator that knows music
Type any frequency from 20 Hz to 20,000 Hz, drag the slider, or step by half steps and single cents. The generator always shows the nearest note and how many cents away it is, at your A4. Set A4 to 432, 442 or anything else, and the note names follow.
Use it to tune by ear against a steady A, to train your ear on intervals, to check a speaker or subwoofer, or to find the frequency of a hum.
Useful frequencies
| What | Hz |
|---|---|
| A4 at standard pitch | 440.00 |
| A4 at 432 | 432.00 |
| A4 at orchestra pitch | 442.00 |
| Middle C (C4) | 261.63 |
| Low E of a guitar (E2) | 82.41 |
| Low E of a bass (E1) | 41.20 |
| Mains hum (Europe / US) | 50 / 60 |
| Test tone | 1000.00 |
Shortcuts
Keyboard
- Space plays and stops
- ← → move a half step
- ↑ ↓ move 1 Hz; with Shift, 0.1 Hz
Safety
Look after your ears and speakers
Start quiet: high tones and square waves tire your ears fast. Turn the volume up slowly, take breaks, and never test hearing limits at high volume. Small speakers cannot play very low tones; if you hear nothing below about 100 Hz on a phone, try headphones.
Questions
Can I play a 432 Hz or 440 Hz tone?
Yes. Tap the 432 or 440 preset, or type any value. The tone keeps playing until you stop it, so you can tune an instrument to it by ear.
Why can I not hear low tones on my phone?
Phone and laptop speakers are too small to play deep bass. Below about 100 to 200 Hz they get very quiet. Use headphones or a proper speaker for low tones.
Is it safe to play high frequencies?
At a low volume, yes. Start quiet, raise the volume slowly and take breaks. High tones and square waves tire your ears fast, and loud test tones can damage hearing and tweeters.