About PitchDetector.io

A free online tool for identifying musical pitches in real-time.

Purpose and Scope

PitchDetector.io is a measurement and learning tool for individual pitched sounds. It combines a live microphone detector and timed pitch-stability test with a frequency-to-note calculator, a complete note-frequency chart, and an explanation of how browser pitch estimation works. It is designed for musicians, singers, students, and developers who need to inspect a note rather than follow an instrument-specific tuning preset.

Method and Privacy

The live detector uses the Web Audio API to read short microphone samples and an autocorrelation-style calculation to estimate the strongest repeating period. That period becomes a frequency, which is mapped to the nearest note at A4 = 440 Hz.

Microphone processing happens locally in the browser. Audio is not uploaded or stored. A browser microphone is appropriate for practice and exploration, but room noise, harmonics, vibrato, and device processing can affect the result.

What the Tools Help You Do

  • Ear training — verify the notes you hear
  • Vocal practice — check your singing pitch
  • Instrument tuning — fine-tune any instrument
  • Music transcription — identify notes in a melody
  • Sound analysis — measure frequencies of any sound

Maintenance and Corrections

PitchDetector.io is built and maintained by independent developer John Sorrentino. Frequency tables use 12-tone equal temperament, and calculation pages show their reference pitch and formulas so results can be checked independently. Use the contact page to report a reproducible browser, device, frequency, or note-mapping issue.