How to Use the Tone Generator

Set Frequency: Type an exact number into the Hz box, or use the slider below it to sweep through frequencies continuously.
Select Waveform: Choose between Sine (smooth, pure tone), Square (hollow, buzzy), Triangle (soft, brassy), or Sawtooth (bright, raspy).
Press Play: Click the large play button to start generating the tone. Warning: Be careful when using headphones, especially with high frequencies. Start with low volume on your device to prevent hearing damage.

Understanding Waveforms

The "shape" of a sound wave determines its timbre (tone color). While a frequency determines the pitch, the waveform determines the character.

Sine Wave: The purest possible sound. It contains only a single fundamental frequency with absolutely no overtones (harmonics). It sounds like a smooth whistle and is perfect for hearing tests.
Square Wave: Contains only odd harmonics. It has a hollow, slightly reedy sound (resembling a clarinet or early 8-bit video games).
Sawtooth Wave: Contains both even and odd harmonics. It sounds very bright, raspy, and buzzing (like a bowed string instrument or a brass section). Because it is rich in overtones, it is the primary building block of subtractive synthesizers.
Triangle Wave: Like the square wave, it contains only odd harmonics, but their volume rolls off much faster. The result is a sound that is softer than a square wave but slightly brighter than a pure sine wave (resembling a flute).

Common Uses for Tone Generators

Hearing Tests: Sweeping a sine wave from 20 Hz up to 20,000 Hz allows you to test the upper and lower limits of your hearing.
Speaker Calibration: Sound engineers use a 1000 Hz (1 kHz) sine wave as a standard reference tone to calibrate audio equipment and align levels across different mixers and speakers.
Tinnitus Relief: Some individuals find temporary relief from tinnitus (ringing in the ears) by listening to specific frequencies or matching the pitch of the ringing.
Tuning Instruments: A tone generator can act as an infinite pitch pipe. You can generate a 440 Hz tone to tune your orchestra or band.

Frequently Asked Questions

As we age, it is completely normal to lose the ability to hear very high frequencies—a condition known as presbycusis. While a healthy teenager might hear up to 18,000 Hz or even 20,000 Hz, an adult in their 40s might only hear up to 14,000 Hz or 15,000 Hz. Also, your device's speakers (especially laptop or phone speakers) might not physically be able to reproduce frequencies above 15kHz or below 50Hz. For the most accurate test, use high-quality studio headphones.

Hertz is the unit of measurement for frequency. It represents the number of cycles (or vibrations) per second. A frequency of 440 Hz means the sound wave vibrates 440 times every single second.