Safety warning

Protect your hearing: Always start with low volume settings and gradually increase. Prolonged exposure to high-volume audio, especially at high frequencies, can cause permanent hearing damage. Use this tool responsibly.

What is an audio frequency?

An audio frequency is the rate at which sound waves oscillate, measured in Hertz (Hz). One Hertz equals one cycle per second. The human ear can typically detect frequencies between 20 Hz and 20,000 Hz (20 kHz), though this range decreases with age. Lower frequencies produce deep bass sounds, while higher frequencies create treble tones. The standard reference pitch for musical tuning is A4 at 440 Hz, known as "concert pitch."

How do sound waves work?

Sound travels as pressure waves through air or other mediums. These waves have two key properties: frequency (how fast they oscillate) and amplitude (how intense they are). When a speaker cone vibrates at a specific frequency, it pushes and pulls air molecules, creating compressions and rarefactions that our ears interpret as sound. Different waveform shapes—sine, square, triangle, and sawtooth—produce distinct tonal qualities even at the same frequency.

Tool description

The Audio Frequency Generator creates pure tones at any frequency within the human hearing range (20 Hz to 20,000 Hz). It uses the Web Audio API to generate real-time audio signals with adjustable waveform types, volume control, and live visualization. The tool is perfect for audio testing, ear training, calibration, and educational purposes.

Features

  • Precise frequency control: Generate any frequency from 20 Hz to 20,000 Hz with single-hertz precision
  • Multiple waveform types: Choose between sine, square, triangle, and sawtooth waves for different tonal characteristics
  • Real-time visualization: Watch the waveform oscillate on a live canvas display that reflects the actual audio output
  • Preset frequencies: Quick access to common frequencies including musical notes, test tones, and solfeggio frequencies
  • Volume adjustment: Fine-tune output volume from 0% to 100% to prevent hearing damage and match your needs

Waveform types explained

Waveform Description Sound character
Sine Pure, smooth oscillation Clean, pure tone with no harmonics
Square Alternates between two levels Hollow, buzzy sound rich in odd harmonics
Triangle Linear rise and fall Softer than square, slightly hollow
Sawtooth Linear rise, instant drop Bright, harsh sound with all harmonics

Common preset frequencies

Frequency Description
20 Hz Lower limit of human hearing
60 Hz Deep bass, common electrical hum frequency
261.63 Hz Middle C (C4) on a piano
440 Hz A4 - International concert pitch standard
528 Hz Solfeggio frequency, often called the "love frequency"
1000 Hz Standard test tone used in audio calibration
15000-20000 Hz Upper range, often inaudible to adults

Use cases

  • Speaker and headphone testing: Verify that your audio equipment can reproduce the full frequency range without distortion or dead spots
  • Hearing tests: Check your personal hearing range by identifying the highest and lowest frequencies you can perceive
  • Musical tuning reference: Use the 440 Hz tone or other musical frequencies to tune instruments by ear
  • Audio system calibration: Test subwoofers with low frequencies and tweeters with high frequencies to ensure balanced sound reproduction
  • Educational demonstrations: Teach students about sound waves, frequency, and the physics of audio in an interactive way