Play a pure tone at any frequency from 20 Hz to 20 kHz. Choose the waveform, jump to any musical note, and move the sound to the left or right.
Free, no sign-up
4 waveforms
Note picker
Stereo balance
Frequency
Hz
A4 · 0¢
201001k10k20k Hz
Waveform
Jump to note
Octave
Note frequencies (octave 4)
A4 = 440 Hz
Note
Frequency
C4
261.63 Hz
C♯4
277.18 Hz
D4
293.66 Hz
D♯4
311.13 Hz
E4
329.63 Hz
F4
349.23 Hz
F♯4
369.99 Hz
G4
392.00 Hz
G♯4
415.30 Hz
A4
440.00 Hz
A♯4
466.16 Hz
B4
493.88 Hz
Protect your ears
Start with the volume low and raise it slowly, especially with headphones. High frequencies can sound quiet but still harm your ears when the volume is high.
Speaker test: slowly move the slider up from 20 Hz to hear where your speakers start to play bass. Use the balance control to check the left and right channels one at a time.
How to use the tone generator
Why use it
A pure tone at an exact frequency is useful for tuning by ear, testing speakers and headphones, and hearing experiments.
How to use it
Set a frequency with the slider, the number field or the note picker, choose a waveform and press Play. Start with the volume low.
Frequently asked questions
What can I use a tone generator for?
You can use it for tuning instruments by ear, testing speakers and headphones, finding room resonances, hearing tests, science experiments and sound design.
What frequency range can humans hear?
About 20 Hz to 20,000 Hz for young people. The upper limit drops with age, and many adults can’t hear above 15–17 kHz.
Is it safe to play loud tones?
Start at a low volume, especially with headphones. Loud tones played for a long time, especially high ones, can damage your hearing and your speakers.
