Online Tone Generator – Free 20Hz to 20kHz Frequency Generator
Generate precise sine, square, sawtooth and triangle test tones from 20Hz to 20,000Hz directly in your browser – 100% free, no signup.
This online tone generator lets you enter an exact frequency between 20Hz and 20,000Hz and press Play to instantly hear a pure test tone sampled at professional 44.1kHz quality. The sound continues until you press Stop, making it ideal for extended audio tests and experiments.
Our tone and frequency generator supports four different waveforms: Sine (smooth pure tone), Square (rich in harmonics), Sawtooth (bright, sharp sound), and Triangle (mellow alternative to sine). Click the waveform buttons to choose the character that best fits your test.
How to use this online tone generator: enter a frequency between 20Hz and 20,000Hz, choose a waveform, then click Play and adjust the volume slider to a comfortable, safe level before listening.
Important Safety Notice: Always ensure headphones or speakers are at low volume before playing tones to prevent hearing damage or equipment harm. High frequencies at loud volumes can be particularly dangerous.
Browser Compatibility
Our Online Tone Generator works flawlessly with Chrome, Firefox, Safari and Edge. If you don't hear sound:
- Update your browser to the latest version
- Check your volume settings and mute switches
- Try our downloadable WAV option as a universal fallback
Pro Tips for Using the Tone Generator
Keyboard shortcuts: click the frequency box, then use:
- Up/Down arrows: adjust by 1Hz increments for fine tuning
- Shift + Up/Down: adjust by 10Hz increments for faster changes
- Use a reference tone like 440Hz for tuning instruments or 1,000Hz for equipment calibration
Share Custom Tones Easily
Create shareable links for specific frequencies and waveforms so you and others can open the same settings instantly:
- Single frequency: /?freq=432 (432Hz example)
- Waveform only: /?waveform=square
- Combined: /?freq=500&waveform=square
Common Frequency Uses
Popular frequencies and how people use this online tone generator:
- 440Hz: standard musical pitch (A above middle C) for tuning instruments
- 432Hz: alternative tuning favoured by some musicians for a warmer sound
- 1,000Hz: common reference tone for audio equipment testing and calibration
- 17.4Hz: very low frequency for subwoofer testing – use our subwoofer test for more tools
- 8,000–20,000Hz: high-frequency hearing range tests – see the dedicated online hearing test
What Can You Do With This Online Tone Generator?
People use ToneGeneratorOnline.net for many real-world audio tasks. Here are some of the most common:
- Hearing checks: sweep through different frequencies to get a basic sense of which tones you can hear. For a structured experience, use the dedicated online hearing test.
- Speaker and subwoofer testing: play low frequencies (for example 20–80Hz) to reveal rattles, buzzes or limitations in your subwoofer. You can also visit the subwoofer testing tool for focused tests.
- Instrument tuning: use reference pitches like 440Hz or 432Hz to tune guitars, keyboards and other instruments, or try the specialised instrument tuning page.
- Acoustic experiments & education: demonstrate waveforms, harmonics and frequency response for students or in the studio using the different wave shapes.
- Sound design & calibration: generate test tones to align levels between different devices, audio interfaces and mixing environments.
More Free Online Audio Tools
ToneGeneratorOnline.net includes a full suite of free browser-based tools that complement the main tone generator:
- Multiple Tone Generator – play or export several tones at once.
- Frequency Sweep Generator – sweep through a range of frequencies automatically.
- Online Noise Generator – create white, pink and other noise types for testing and masking.
- Binaural Beats – generate brainwave entrainment-style tones in your browser.
- Online Voice Generator and Online Voice Recorder – basic voice tools for quick recording and playback.
- Metronome – keep perfect time when practising music.
- Acoustic Theory – learn the basics of sound, frequency and acoustics.
Why Musicians and Engineers Trust ToneGeneratorOnline.net
Since 2015, ToneGeneratorOnline.net has focused on doing one thing extremely well: providing accurate, reliable test tones and audio tools directly in the browser.
- Free and instant: no account, no paywall, no software to install.
- Browser-based: works on modern versions of Chrome, Safari, Firefox and Microsoft Edge on desktop and mobile.
- Professional-quality output: tones are generated at 44.1kHz using the HTML5 Web Audio API.
- Multiple companion tools: from sweeps and noise to hearing tests and metronomes, everything is designed for practical, everyday use.
- Transparent about safety and privacy: we emphasise safe listening levels and provide a clear privacy policy.
Safety and Hearing Health
Test tones can become uncomfortable or harmful at high volumes, especially at very low or very high frequencies. Always start with your device volume low and increase gradually.
- Avoid playing extremely loud tones for long periods of time.
- Be extra careful with headphones and in-ear monitors where the driver is close to your eardrum.
- If you experience ringing in the ears, pain or discomfort, stop immediately and rest in a quiet environment.
- For medical questions or concerns about your hearing, consult a qualified hearing specialist.
Tone Generator Online – Frequently Asked Questions
Is the online tone generator free to use?
Yes. The tone generator online and all core tools on ToneGeneratorOnline.net are completely free to use in your browser. No registration or login is required.
What frequencies can I generate with this tone generator online?
You can generate pure tones from 20Hz up to 20,000Hz, which covers the typical human hearing range from low bass to very high treble.
What can I use the tone generator online for?
Common uses include quick hearing checks, speaker and subwoofer testing, audio equipment calibration, acoustic experiments and educational demonstrations. For more specialised tools, explore our subwoofer testing and online hearing test pages.
Do I need to install any software or plugins?
No installation is required. The tone generator online runs entirely in your web browser using the HTML5 Web Audio API and works on all modern desktop and mobile devices.