Generator Tools
Online Tone Generator
Generate sine, square, triangle, and sawtooth tones from 1 Hz to 22 kHz in your browser. Stereo, left, or right channel. No signup, no upload.
Listen at low volume first
Some tones, especially high frequencies and square or sawtooth waves, can sound louder than they look on the meter. Start at the default 20 percent, then nudge the volume up only if you need it.
Frequency
440.0 Hz
Nearest note: A4 (+0 cents)
Accepts plain numbers (440), decimals (261.63), and k or kHz shortcuts (1k, 1.5 kHz). Range 1 Hz to 22050 Hz.
Waveform
The four standard oscillator shapes. Sine is the cleanest. Square, triangle, and sawtooth add harmonics and sound richer.
Output channel
Switch between stereo, left-only, and right-only to test individual headphone or speaker channels.
Volume
A linear master gain applied to the oscillator output. The dBFS readout is the headroom below digital clipping at full scale 1.0.
20 %
-14.0 dBFS
Frequency presets
Common tones for tuning, hearing checks, broadcast reference, and testing. Tap any preset to load it; the tone continues playing if it was already on.
Tuning
Hearing test
Reference
Tinnitus
Hum and noise
What the waveforms actually sound like
- Sine is the fundamental at one frequency with no harmonics. It sounds soft and pure, the closest match to a tuning fork.
- Square contains only odd harmonics (1, 3, 5, 7 times the fundamental) at decreasing amplitude. It is bright, hollow, and noticeably louder than a sine at the same gain.
- Triangle also contains only odd harmonics, but the amplitude falls off faster than a square. It is mellower than square and brighter than sine.
- Sawtooth contains every harmonic (both even and odd) and is the buzziest. It is the building block for synthesised strings and brass.
Hearing safety
- Sine waves carry less perceived loudness than square or sawtooth waves at the same digital level. Drop the volume before changing waveform.
- Long sustained tones can damage hearing well below the volume that feels uncomfortable. Use short tests, take breaks, and start at 20 percent or below.
- This tool is not a substitute for medical audiometry. Use it for quick checks, audio gear tests, and tuning, not for diagnosis.
How to use
- Set a frequency in the input or drag the logarithmic slider, then press Play tone to start the oscillator.
- Choose a waveform: Sine is the cleanest pure tone, while Square, Triangle, and Sawtooth add progressively richer harmonics.
- Switch the output channel to Both, Left only, or Right only to test individual speakers or headphone drivers.
- Adjust the volume slider (defaults to 20 percent) and use the percent chips for quick presets. Stay at the lowest level that lets you hear the tone clearly.
- Tap a preset for tuning, hearing-test bands, broadcast reference tones, tinnitus frequencies, or mains-hum frequencies. Use the +1 semitone, +1 octave, and Hz nudge buttons to move precisely from there.
About this tool
Online Tone Generator plays sine, square, triangle, and sawtooth tones in your browser using the Web Audio API. Set the frequency anywhere from 1 hertz up to 22050 hertz (the Nyquist limit at the common 44.1 kHz audio sample rate) and the oscillator runs in real time with no latency, no ads, and no audio file fetched from a server. The frequency field accepts plain numbers, decimals, and k or kHz shorthand (1k, 1.5 kHz), and a logarithmic slider from 20 Hz to 20 kHz gives smooth musical resolution across the full human hearing range. Step controls move the pitch by 1 Hz, 10 Hz, a single semitone, or a full octave, so you can sweep to a target note by ear without recalculating ratios. A live readout shows the nearest 12-TET note name (with cents offset from A4 = 440 Hz), the wavelength in air at 20 degrees Celsius, and the volume in both percent and dBFS, so every setting is auditable at a glance. Output routing handles stereo, left-only, and right-only modes for testing individual headphone or speaker channels, plus temporary left and right mute switches for quick A/B comparisons. The volume slider is capped well below digital full-scale and defaults to 20 percent to protect hearing, with safe quick-set chips at 5, 10, 20, 35, 50, and 70 percent and a one-click mute. Built-in frequency presets cover concert-pitch tuning (A4 at 440 Hz and 432 Hz, middle C, common string fundamentals), audiometric hearing test bands (125 Hz, 250, 500, 1k, 2k, 4k, 8k, 12k), broadcast reference tones (1 kHz line-up, 400 Hz EBU), tinnitus reference frequencies (6, 8, and 10 kHz), and the 50 and 60 Hz mains-hum frequencies used in Europe and Asia (50) and North America (60). Useful for tuning instruments, calibrating speakers and headphones, checking left-right balance, identifying ground-loop hum, finding the pitch of a noise complaint, building reference tracks, demonstrating harmonics for music students, and any quick test that needs a steady audible signal. Audio playback starts and stops with smooth gain ramps to prevent clicks, and the AudioContext is closed when you leave the page so no audio resource is left running in the background. Everything happens in your browser; no audio is uploaded, recorded, or stored, and no microphone access is requested.
Free to use. Works in your browser. No signup, no login.
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