Pitch Detector
The detector finds the pitch of one note at a time from your microphone with the YIN algorithm, in a range of 50 Hz to 2,000 Hz. It shows the nearest note, the frequency and how many cents sharp or flat you are, with A4 at 440 Hz.
How to use
- Press Start listening and allow microphone access. Nothing is requested until you press the button.
- Sing, whistle, hum or play one note at a time. The large label shows the nearest note and octave, with the frequency in Hz and how many cents sharp or flat you are.
- Press Hold to freeze the reading, or watch the graph to see how steady your pitch was over the last ten seconds. Change A4 if you play with a different reference pitch.
How it works
The pitch is found with the YIN algorithm, which looks for the shortest repeat period in the latest fraction of a second of sound. Frequency is the sample rate divided by that period. The range covered is 50 Hz to 2,000 Hz.
The nearest note comes from equal temperament: MIDI note = 69 + 12 x log2(f / A4). The note name and octave come from that number, with A4 = 440 Hz by default and C4 as middle C.
Cents measure the gap to the nearest note: cents = 1200 x log2(f / note frequency). One semitone is 100 cents, so the reading always falls between -50 and +50.
FAQ
Can it read chords or several people singing?
No. It follows a single melodic line. Chords, harmony and background music contain several pitches at once, so the result will jump or show nothing.
Why does the note sometimes jump an octave?
Some voices and instruments have strong overtones, and the detector can lock onto a harmonic instead of the fundamental. Keep the note steady, sing closer to the microphone and avoid background sound.
Why is the pitch graph blank?
The graph only draws while a clear pitch is heard. Silence, breath noise and very quiet sounds are ignored.
Is my audio recorded?
No. The signal is analyzed in your browser and is never stored or sent anywhere.