Left / right channels
Best tested with headphones. Mono audio or device settings can change what you hear.
Online Tone Generator
Play any frequency from 20 Hz to 20,000 Hz. Adjust your tone instantly, run a sweep, or check your speakers — no download or signup.
Set your tone
Ready
20 – 20,000 Hz
Hz
20 Hz200 Hz2 kHz20 kHz
Start with low volume, especially with headphones. Tones can be uncomfortable at high levels.
Waveform preview
STOPPED
WAVEFORM / SINEIllustration
QUICK FREQUENCIES
WAVEFORM
Works in your browser. No uploads required.
Frequency sweep
Glide through frequencies to explore how your speakers respond. If something sounds unusual, hold that frequency and check nearby tones.
The sweep uses a logarithmic scale. Set a low device volume before starting.
CURRENT FREQUENCYREADY
80 Hz
80 Hz8 kHz
LAST MARKED FREQUENCYNone yet
Mark & hold freezes the tone you hear. Recheck sweeps around that marked frequency, then returns to it.
Speaker & headphone check
Play short test tones in the left or right channel, or try a couple of low-frequency tones. Each check stops automatically after 3 seconds.
Low-frequency tones
Compare 100 Hz and 200 Hz at a low volume. Small speakers may not reproduce deep bass.
These are informal playback checks, not calibrated hearing tests or a diagnosis. Never raise the volume to compensate for a tone you cannot hear.
How to use this tone generator
Enter a frequency between 20 and 20,000 Hz, choose a waveform, and press Play tone. You can change the frequency or volume while the sound is playing. Start at a low device volume, especially when using headphones.
Which waveform should you use?
Different waveforms have different harmonic content, even at the same frequency.
Sine wave
A pure, smooth tone with no added harmonics. A useful starting point for frequency exploration.
Square wave
A buzzy sound with strong odd harmonics.
Triangle wave
A softer sound with weaker odd harmonics.
Sawtooth wave
A bright, rich sound containing both even and odd harmonics.
Frequently asked questions
Can I generate a 440 Hz tone?
Yes. The generator starts at 440 Hz, a common reference pitch for musical tuning. Press Play tone, or enter another frequency in the box.
What frequency range does the tool support?
You can select values from 20 Hz to 20,000 Hz. Whether you actually hear the tone depends on your hearing, speakers, headphones, and their frequency response.
Why can't I hear very low or high tones?
Small speakers often cannot reproduce deep bass, and many people cannot hear the highest frequencies. Keep the volume low rather than turning it up to compensate for an inaudible tone.
Does the tool record audio or upload files?
No. It generates sound in your browser using the Web Audio API. There is no microphone access, upload, or account requirement.
How does the frequency sweep work?
Choose a start frequency, an end frequency, and a duration. The browser smoothly changes the sine-wave frequency on a logarithmic scale. Mark a troublesome spot to hold it or recheck a small nearby range.
Do these checks diagnose hearing loss or certify speakers?
No. Output levels are not calibrated and devices vary. These checks are for general audio experimentation, not diagnosis or certification.