Tone Generator
Drag the frequency slider while playing to hear the pitch change.
Start at low volume. High frequencies and square waves can be harsh.
Status
Press Play to start the tone.
Frequency
440 Hz
Waveform
sine
Play a pure tone at any frequency from 20 to 20000 Hz. Choose sine, square, sawtooth, or triangle waves, run a full-range sweep, and test speakers.
Drag the frequency slider while playing to hear the pitch change.
Press Play to start the tone.
Hearing is logarithmic: the jump from 100 to 200 Hz sounds as big as 1000 to 2000 Hz. The slider maps exponentially so each millimeter of drag changes the perceived pitch evenly, with fine control down low where it matters most.
Sine is a pure single pitch. Triangle adds soft harmonics, square sounds hollow and buzzy, and sawtooth is bright and harsh. Use sine for hearing tests and square or sawtooth to stress-test speakers.