Frequency Generator Online — Free Browser-Based Signal Generator
Generate any audio frequency online — from 20 Hz deep bass to 20 kHz brilliance — with sine, square, sawtooth, and triangle waveforms. The fast, free, browser-based signal generator for engineers, musicians, and tinkerers.
What is a Frequency Generator?
A frequency generator (also called a signal generator or function generator) is a tool that produces periodic electrical or audio signals at a specified frequency and waveform. In hardware form these are key bench-test instruments; in software, they let engineers, audio professionals, and hobbyists generate test tones without specialised equipment.
Our online frequency generator runs entirely in your browser using the Web Audio API. You get full audible-range coverage (20 Hz – 20 kHz), four classic waveforms, and one-tap presets for the frequencies you use most.
Features
Full Audible Range
20 Hz to 20 kHz coverage in 1 Hz steps — everything from sub-bass to upper treble.
4 Classic Waveforms
Switch instantly between sine, square, sawtooth, and triangle waves.
Quick Presets
One-tap shortcuts to the most-used reference frequencies (100, 440, 1k, 4k, 8k).
Real-Time Adjust
Drag the slider and the frequency updates live with sample-accurate timing.
Mobile First
Beautifully usable on phones — no fiddly menus, no pop-up ads.
Volume Limited
Smooth fade-in prevents pops. Hearing safety reminders for high frequencies.
Common Uses
Sweep tones to find where your speakers peak, dip, or rattle.
Use presets for Concert A, C, and other reference frequencies.
Find your personal high-frequency cutoff and any frequency gaps.
Demonstrate beats, resonance, harmonics, and Fourier concepts.
How to Use
1. Choose Waveform
Pick sine, square, sawtooth, or triangle depending on the tone character you need.
2. Set Frequency
Use the slider or tap a preset to dial the exact frequency you need.
3. Adjust Volume
Start at low volume — pure tones can be louder than they feel.
4. Press Play
Hit Play and the tone keeps playing continuously until stopped.
Frequently Asked Questions
They are essentially the same thing — both produce continuous waveforms at a specific frequency. "Tone generator" is more common for musical use; "frequency generator" is more common for engineering and testing.
1 kHz is the universal standard test tone. To test full-range response, sweep from 20 Hz up to 20 kHz and listen for dips, peaks, or distortion.
Sine waves are best for clean frequency-response testing because they contain only one frequency. Square waves are useful for testing speaker transient response.
The slider snaps to whole Hz, but the underlying engine accepts any decimal frequency. Future updates will expose direct numeric input.
Once the page is loaded, the tone generation runs entirely in your browser without any network calls.
Hearing Safety
Pure tones — especially below 40 Hz or above 10 kHz — carry significant energy at high volumes. Start low and protect your hearing and speakers.