UNDERSTAND YOUR RESULT
What note am I singing or playing?
The large letter is the nearest musical note. The small number is its octave: A4 is the A above middle C and, with the usual concert reference, measures 440 Hz.
A sharp sign (♯) means the note is one semitone above its letter. The cents reading shows how close your sound is to the displayed note: negative values are flat, positive values are sharp, and a value near zero is centered.
For the clearest answer, use one sustained tone in a quiet room. Background noise, strong overtones, vibrato, and more than one note at once can make the display flicker or select another octave.
Want to practise matching the note after you find it? Use the online pitch detector as a tuning guide.
UNDERSTAND PITCH
What is a pitch detector?
A pitch detector listens for the repeating pattern in a single sound and estimates its fundamental frequency. Frequency is measured in hertz (cycles per second), as defined by NIST. The app compares that measurement with a tuning reference and presents a note name, octave, staff position, and cents value.
“The SI unit for frequency is the hertz (Hz).” — National Institute of Standards and Technology
A detector is most useful for:
- singers matching a target note or warming up;
- instrumentalists checking intonation;
- learners connecting what they hear with written notation.
Use one sustained tone. Chords, heavy vibrato, room noise, and a distant microphone add competing patterns, so let the display settle before responding.
The cents meter shows the distance to the nearest equal-tempered note. The reference piano provides a starting pitch, while the optional voice guide gives broad choir-style ranges; it is not a vocal diagnosis.
How does this pitch detector work?
The detector measures a waveform and looks for a regular cycle. This comparison shows which sources are easiest to detect:
Source quality for pitch detection| Input | Expected result | Why |
|---|
| Sustained vowel or single instrument note | Best | One stable fundamental |
| Vibrato or a distant microphone | Variable | The frequency moves or loses clarity |
| Drum, breathy consonant, or chord | Unreliable | No single sustained pitch |
The frequency is compared with twelve equal semitones per octave, then the cents meter shows whether the result is flat, centered, or sharp.
How should you choose a tuning reference?
Calibration sets the reference frequency used to label the detected sound:
Common A4 reference choices| Reference | When to use it |
|---|
| 440 Hz | Most general practice and digital instruments |
| 438 or 442 Hz | When an ensemble or recording specifies it |
| 432 Hz | Only when your musical context explicitly requires it |
Choose the same reference as the people or instruments you are playing with. The detected frequency does not change; only its musical label and cents offset do.
Sources: NIST frequency definition · NIST SI guide
FAQ
Questions about finding a note
Can I hum to find a note?
Yes. Hum one steady note close to the microphone and wait for the display to settle. A clear vowel or a sustained instrument note is usually easier to identify than a breathy sound.
Can it identify a note from an instrument?
Yes. Play one string, key, or other sustained note at a time. Mute the other strings and reduce background noise for the clearest result.
Why does the octave change?
Strong overtones, noise, or a note that is not sustained can make a detector choose a neighbouring octave. Move closer to the microphone and play or sing one clean note.
Do I need to allow microphone access?
Yes. The note finder analyses live microphone audio in your browser. Allow access when prompted, then tap Stop detecting when you are finished.
Is my audio uploaded or recorded?
No. Audio is analysed live on your device. This page does not record, save, or upload your microphone audio.
Can it tell me what song I am singing?
No. This is a single-note finder. It shows the musical note and tuning of the sound currently reaching the microphone; it does not identify songs.
Can it identify chords?
No. Chords contain several pitches at once, so this tool is designed for one sustained note at a time.
Can I upload an audio file?
No. The tool currently works with live microphone input only.
PitchDetector