Free online tone generator · No signup · Runs in browser

Free online tone generator

Play pure test tones instantly — 20 Hz to 20 kHz, four waveforms, stereo check, live visualizer. This frequency generator online needs nothing installed and uploads nothing.

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LIVE OSCILLOSCOPE — draws the actual output waveform in real time

Hz
20 Hz200 Hz2 kHz20 kHz

Tip: type up to 22,000 Hz for edge-case testing. ↑/↓ = ±1 Hz, Shift + ↑/↓ = ±10 Hz. Dragging the slider bends pitch live without restarting.

Note
Waveform
Channel

Isolate a dead earbud or speaker.

-100 L0+100 R

Capped at 30% for safety. Start low, raise gradually — high frequencies can feel loud without sounding loud.

Stops automatically so an uncomfortable pitch can't run forever.

Safe use: start at the lowest volume, keep high-frequency tones brief, and stop if anything feels uncomfortable. Everything runs locally in your browser — nothing is recorded or uploaded.

Runs locally

Web Audio API, no upload

Tone generator free

No account, no limits

Capped for safety

Max 30%, auto-stop

Share & download

URL presets + WAV

HOW IT WORKS

Play a test tone in 3 steps

1

Pick a frequency

Drag the logarithmic slider, type an exact Hz value, tap a chip, or choose a musical note. The slider bends pitch live while playing — ideal as a hertz generator and pitch generator.

2

Choose waveform & volume

Sine for pure tones, square for harsh checks. Volume starts at 14% and is hard-capped at 30% — raise it slowly.

3

Press Play & inspect

Watch the live oscilloscope, check left/right channels, copy a shareable link, or use tone generator download to save a 10-second WAV.

TEST TONES EXPLAINED

What is an online tone generator?

A tone generator produces a steady audio signal at one exact frequency, measured in hertz (Hz). This online tone generator is also an online frequency generator and frequency generator online: type any tone generator Hz value from 20 Hz to 20,000 Hz and hear that hertz sound instantly. A 440 Hz sine wave — the A above middle C — is the standard tuning reference orchestras use. Low tones like 60 Hz feel like a deep hum through a subwoofer, while high tones like 12,000 Hz sound like a thin whistle.

Unlike MP3 test files, this tool synthesizes every tone live with the Web Audio API. An oscillator node generates the waveform, a gain node controls the safety-capped volume, and a stereo panner routes sound left, right, or center. Because a hertz generator runs entirely on your device, there is zero streaming delay and zero privacy cost — no audio is recorded, nothing is uploaded, and there is no backend at all. It works on phone, tablet, laptop, and desktop, with no app store required.

Why use this tone generator free?

Many frequency tools are cluttered with ads, require accounts, or lock sine waves behind paywalls. This tone generator free tool has no signup, no install, no watermark, and no per-day limit. As a pure frequency player, it starts playback the moment you press Play, bends pitch live as you drag, and syncs your frequency and waveform to the URL so any tone can be shared as a link such as ?freq=432&waveform=sine.

It is built for speed and honesty: a logarithmic slider that matches how pitch feels, a live oscilloscope that draws the real output, a left/right channel check for dead earbuds, one-tap preset chips from 20 Hz to 20 kHz, a musical-note picker across 88 notes, auto-stop timers, and client-side WAV export. Whether you call it a pitch generator, hertz generator, or frequency player, the job is the same — give you a trustworthy reference tone in under two seconds.

Sine wave generator and pure tone generator: waveforms explained

At its core this is a sine wave generator and pure tone generator. A sine wave contains a single frequency with no harmonics, so it sounds smooth and flute-like — the cleanest reference for speaker checks, earbud balance, and pitch matching. If you want the purest hertz sound, always start with sine.

Three extra waveforms turn the same pitch generator into a diagnostic kit. Triangle is a softer, mellower cousin of sine, easier on the ears during long sessions. Square is harsh and buzzy with strong odd harmonics, perfect for exposing distortion, testing alarms, and checking how small phone speakers handle stress. Sawtooth is bright and edgy with all harmonics, ideal for tweeter tests and synth calibration. Switch waveforms while playing — the oscillator morphs without restarting, and the oscilloscope shows the shape change live.

Hertz generator and pitch generator: practical everyday uses

People open a frequency generator online for surprisingly practical reasons. The most common is the speaker and headphone check: play 100 Hz, 440 Hz, and 1 kHz in the left ear, then the right, to catch a dead earbud, a loose cable, or a blown driver. Bass lovers sweep 30–80 Hz to find the lowest note a subwoofer or soundbar reproduces without rattling, while producers hunt room buzzes and vibrating objects with slow sine tones.

Musicians use this pitch generator as a tuning fork that never wears out — dial 440 Hz for A4, 432 Hz for alternative tuning, or pick any note from A0 to C8 to tune guitars, pianos, and synths by ear. Teachers demonstrate octaves, harmonics, and logarithmic hearing with it; testers verify microphone chains, video-call audio, and hearing-aid feedback; meditators layer low drones for focus and relaxation. It confirms a pitch plays through your gear — it is not a calibrated meter and never a medical hearing test.

Multi tone generator and frequency sweep generator, built in

A single tone answers simple questions, but stacked tones reveal beats, distortion, and room problems one tone hides. Our dedicated multi tone generator layers up to four simultaneous frequencies with independent waveform, volume, and pan — try 440 Hz plus 442 Hz to hear a slow 2 Hz pulsing beat, or 220, 277, and 330 Hz for a detuned chord idea.

For full-range testing, the frequency sweep generator glides from any start hertz to any end hertz over a set duration, linear or logarithmic. A 20 Hz to 20 kHz logarithmic sweep is the classic speaker and room response check: listen for volume dips, rattles, and the points where bass or treble fades. Headphone listeners can also explore the binaural beats generator — two close frequencies, one per ear — as a novelty relaxation toy.

Tone generator app and tone generator download: install and save tones

Prefer an app feel? This tone generator app experience needs no app-store tone generator download. It is a lightweight web app: open it in Chrome, Safari, Edge, or Firefox, tap “Add to Home Screen” or “Install,” and it launches full-screen like a native tone generator app while staying under a megabyte. Because synthesis is local, it even keeps working through short connection drops once loaded.

When you need an actual audio file, tone generator download is one click: the “Download 10s WAV” button renders a 10-second, 44.1 kHz stereo WAV of your exact frequency and waveform on-device and saves it as tone-440hz-sine-10s.wav. Use downloads for video editing, ringtones, alarm testing, classroom demos, or playing tones on speakers without a browser. Sharing is equally easy — every setting lives in the URL, so copying the link shares your exact test.

Tone generator Hz chart: what different hertz sounds feel like

Not sure which tone generator Hz value to try? Human hearing spans roughly 20 Hz to 20,000 Hz, but most music lives between 40 Hz and 8,000 Hz. Start low, raise volume slowly, and keep high hertz sound exposure brief.

RangeWhat you hearTry
20–60 HzSub-bass rumble, felt more than heard40 Hz
60–250 HzBass body — kick drums, bass guitar100 Hz
250–2 kHzMids — voice warmth and tuning reference440 Hz
2–6 kHzPresence — clarity, baby cries, alarms4 kHz
6–20 kHzBrilliance — thin whistle, tweeter test8–12 kHz

Tip: test 440 Hz first to set a comfortable level, then explore outward. If a frequency suddenly sounds much quieter, you have likely found your speaker’s roll-off — not a hearing result. Learn more about this project on the about page.

✓ What this tone generator can tell you

  • Whether a pitch plays through your headphones, speakers, or phone
  • Whether the left and right channels both work (dead-earbud check)
  • Roughly where your gear starts rolling off bass or treble
  • A reference pitch to tune an instrument against by ear

✕ What it can't do

  • It is NOT a calibrated instrument — loudness varies by device
  • It is NOT a hearing test — see an audiologist for hearing concerns
  • It cannot diagnose tinnitus, hearing loss, or any medical condition
  • It cannot measure your room or speakers precisely like lab gear

FAQ

Tone generator — frequently asked questions

What is a tone generator? +

A tone generator is an online tool that plays a steady audio signal at one exact frequency, measured in hertz (Hz). This online tone generator is also a frequency generator online and online frequency generator: enter any tone generator Hz value from 20 Hz to 20,000 Hz and hear that hertz sound instantly as a sine wave generator and pure tone generator.

What is a tone generator used for? +

A tone generator is used to test headphones, earbuds, speakers, and subwoofers, check left/right stereo balance, find bass and treble roll-off, tune instruments to a reference pitch like 440 Hz, calibrate synth patches, demonstrate harmonics in class, verify microphone and video-call audio chains, and play low focus or relaxation drones.

How do I use a tone generator? +

Pick a frequency with the logarithmic slider, the Hz number box, a preset chip, or the musical-note picker, choose a waveform and a low volume, then press Play tone. While it plays as a live frequency player you can bend pitch, switch waveforms, pan left/right, set auto-stop, copy a shareable link, or download the tone.

What does a tone generator do? +

It plays one continuous hertz sound at the exact pitch you choose — for example 60 Hz as deep bass hum, 440 Hz as concert-pitch A4, or 8,000 Hz as a high whistle. As a pitch generator and hertz generator it gives you a trustworthy reference tone for testing gear and tuning by ear.

How does a tone generator work? +

This free frequency generator online synthesizes every tone live with the Web Audio API. An oscillator node creates the waveform, a gain node controls the safety-capped volume, and a stereo panner routes it left, right, or center. Because synthesis happens on your device, there is no streaming delay and no backend.

Is there a free tone generator? +

Yes — this tone generator free tool is free forever with no account, no install, and no usage limits. Every sine wave, pitch, and hertz sound is synthesized locally in your browser, so there are no per-tone server costs.

Is there a tone generator app I need to download? +

No app-store tone generator download is needed. This tone generator app works directly in Chrome, Safari, Edge, and Firefox — just open it and press Play. For an app feel, use “Add to Home Screen” or “Install” to launch it full-screen like a native app.

Can I download a tone generator as a file? +

Yes. Use tone generator download (Download 10s WAV) to save your exact frequency and waveform as a 10-second, 44.1 kHz stereo WAV file, for example tone-440hz-sine-10s.wav. Use it for video editing, ringtones, classroom demos, alarm testing, or offline playback without a browser.

What's the difference between sine, square, sawtooth and triangle waves? +

Sine is a pure tone generator signal with one frequency and no harmonics — smoothest and best for reference checks. Triangle is a softer sine alternative. Square is harsh and buzzy with strong odd harmonics, good for distortion and alarm tests. Sawtooth is bright and edgy with all harmonics, good for tweeter and synth tests.

Can I use this to test if one earbud or speaker is dead? +

Yes. Play 440 Hz or 1,000 Hz sine, then switch Channel to Left only and Right only, or drag Pan from −100 to +100. If one side stays silent, that earbud, cable, or speaker driver is dead or disconnected. Also try the frequency sweep generator for a full-range check.

Can I play multiple tones at once? +

Yes. Open the multi tone generator to layer up to 4 simultaneous tones with independent frequency, waveform, volume, and pan. Try 440 Hz + 442 Hz sine waves to hear a slow 2 Hz interference beat, or stack 220, 277, and 330 Hz for a chord drone.

What is a frequency sweep? +

A frequency sweep glides from a start hertz value to an end hertz value over a set duration instead of holding one pitch. Use the frequency sweep generator in logarithmic mode for musical speaker and room tests (20 Hz to 20 kHz), or linear mode to demonstrate how pitch perception works. Listen for rattles, volume dips, and bass/treble fade points.

Is it safe to use a tone generator at full volume? +

Be cautious. This tool caps volume at 30% and starts at 14% for safety, but high hertz sounds can still feel loud without sounding loud. Start low, raise gradually, keep high-frequency tones brief, never hold a phone speaker to your ear, supervise kids and pets, and stop if you feel discomfort, ringing, or dizziness. This is not a medical device or hearing test.

Does this work on iPhone and Android? +

Yes. This online frequency generator works on iPhone, Android, tablets, laptops, and desktops with no install. Browsers require a tap before audio starts, so press Play, then check the silent switch, Bluetooth output, and volume if you hear nothing. As a fallback, download the 10s WAV and play the file directly.

Is my audio recorded or uploaded anywhere? +

No. All synthesis runs locally via the Web Audio API — no microphone access, no recording, nothing uploaded, and no audio requests leave your device. Only a theme preference is stored in your browser, plus frequency settings in the URL when you copy a share link.