Pitch Detector

How to use

1. Use a quiet room when possible. This detector works best with one dominant pitch at a time; chords, breath noise, transients, and complex tones can produce unstable estimates.
2. Confirm the Reference A4 value. Keep the 440 Hz default unless you intentionally use another standard within 415–466 Hz.
3. Choose the preferred microphone for the next Start. Browser default input remains valid when device labels are unavailable; changing the selector does not open a stream.
4. Click Start microphone input. The browser requires a user gesture before it can ask for microphone access, and the chosen input plus A4 value are frozen for that session.
5. Allow microphone access for this site. Camera access is not required.
6. To compare another input, Stop, choose the next microphone, then Start a new session. The page does not merge estimates from different streams.
7. Sing, hum, or play one sustained note at a time.
8. Keep the source reasonably steady and close enough for a clear signal without overloading the microphone.
9. Review the detected note and octave, estimated frequency in Hz, MIDI number, cents, confidence, Stable state, run A4, actual analysis sample rate, and bounded recent accepted estimates.
10. Repeat an unstable or surprising reading. Noise, harmonics, room echo, microphone processing, and range limits can change the estimate.
11. The A4 slider is setup for the next session and locks while capture is pending or running. It changes note/cents mapping and the finite reference-tone frequency, not microphone input.
12. Optional: before opening the microphone, lower system or headphone volume and play the finite 1.5-second A4 sine reference. Reference playback is disabled while microphone capture is pending or running.
13. Click Stop and release microphone when finished. The live result clears and Last pitch session freezes the run context and bounded evidence; interrupted attempts are labeled separately.
14. Reset pitch session releases input, stops any reference, and clears live, recent, frozen, interruption, and error state without creating analytics.
15. Do not use this browser estimate as laboratory calibration, a professional tuning certificate, or a medical voice, vocal-health, or hearing assessment.

What the result means

• Detected note and octave map the estimated frequency to the nearest twelve-tone equal-tempered note under the selected A4 reference, such as A4 or C4. They do not identify an instrument, timbre, song, chord, or singing quality, and octave errors can occur.
• Frequency is the YIN estimate from local microphone samples, in hertz. It is not a generator setting or calibrated-microphone measurement; sample rate, hardware, room sound, AGC, echo cancellation, and noise suppression can affect it.
• Pitch is the perceived highness or lowness of sound. It relates closely to frequency but is also influenced by harmonics, timbre, and hearing; this page still reports an algorithmic estimate.
• A note is the nearest equal-tempered name for the estimate. It is not song recognition or chord detection. Octave is that note name's register, and harmonic-rich input can be classified one octave high or low.
• MIDI is the rounded number of the nearest semitone. It is only a pitch-number mapping; this page neither receives nor sends MIDI messages.
• Cents is the offset from the nearest equal-tempered semitone under the selected A4. Negative is below its center and positive is above; the nearest note changes around ±50 cents. It is not an overall performance score, especially for microtonal or non-equal-tempered music.
• Confidence is YIN's internal 0–1 periodicity score. The page requires at least 0.65 for a valid voiced pitch. High confidence is not laboratory accuracy; low confidence can reflect silence, noise, breath, several notes, instability, processing, or an out-of-range signal.
• Stable = yes requires a valid high-confidence estimate to remain within about 40 cents for about 400 ms. It means recent estimates were consistent, not perfectly tuned, medically normal, or professionally calibrated.
• Recent accepted estimates contains at most 20 valid voiced results with confidence at least 0.65, sampled no faster than about once per 100 ms. It is current-session evidence, not a recording, persistent history, or per-frame dump; Reset clears it.
• The allowed A4 range is 415–466 Hz, with 440 Hz by default. Changing A4 changes note and cents mapping plus the optional sine reference; it does not calibrate the microphone or alter the incoming sound.
• The default detection range is 50–1,200 Hz. This is neither the human hearing range nor complete coverage of all voices and instruments. Signals below or above it can be absent, rejected, unstable, or misclassified.
• The A4 reference is a finite 1.5-second local Web Audio sine tone at low app gain. It is available only without an active microphone session, is not an acoustic calibration source, and does not verify speaker output or hearing.

Limitations

• YIN pitch estimate only — not laboratory calibration.
• Room noise and microphone AGC affect stability. Prefer headphones with reference tones.
• YIN-style periodicity estimation is intended for one dominant pitch. It cannot reliably separate chords, multiple instruments, or simultaneous notes, and it cannot eliminate octave, harmonic, or subharmonic errors.
• The 50–1,200 Hz detector range is an implementation measurement band, not a hearing range or proof that an undetected sound is absent.
• This page cannot calibrate a microphone, measure sound-pressure level, prove absolute note accuracy, diagnose a microphone or instrument, rate singing ability, or assess voice, vocal-cord, hearing, or other medical health.
• The browser and operating system may apply AGC, echo cancellation, noise suppression, resampling, or other processing that the page cannot remove or fully inspect.
• Microphone samples are processed in this tab to derive pitch estimates. This tool does not automatically save a recording file or upload raw microphone audio; browser and OS permission controls still apply.
• Reference playback is disabled during pending or active microphone capture, and Start stops any remaining reference sound. This separation reduces self-detection and feedback risk but is not a listening-safety guarantee.

Troubleshooting

Microphone permission was denied

Open site settings for devicemetrik.com, allow microphone access only, then reload or click Start microphone input again. Camera access is not required.

No pitch appears

Confirm input is active, select the correct microphone, sustain one steady note, move slightly closer without overloading the input, reduce noise, and check that the likely frequency is within 50–1,200 Hz.

The note jumps between octaves

Use one steady note, reduce room echo, try a less harmonic-rich source, and move away from speakers. Octave and harmonic errors are possible and are not a hardware diagnosis.

Confidence remains low

Reduce background noise, sustain the note longer, avoid chords and breath-heavy transients, and review microphone processing. Low confidence does not prove microphone damage.

Stable never changes to Yes

Hold approximately the same pitch for at least about 400 ms, avoid large vibrato, and keep confidence above 0.65. Stable does not mean perfectly tuned.

Cents changed after changing A4

That is expected: A4 changes the equal-tempered note and cents reference. It does not change the frequency measured from the microphone.

The A4 reference button is unavailable

Reference playback is deliberately unavailable while microphone capture is pending or running. Stop and release the microphone first, lower system volume, then play the finite reference.

Reference playback could not start

Check browser audio policy, tab audio permission, and the selected output. Reference failure does not affect microphone detector eligibility and is not a hardware diagnosis.

I want to compare another microphone

Stop the current session, choose the preferred input for the next Start, then begin a new session. Changing the stopped selector does not request permission or open a stream.

Detection stops after switching tabs

This is expected interruption behavior. Hidden pages stop and release the stream; return to the tab and deliberately start a new session.

Very high or low notes are not detected

The current range is 50–1,200 Hz. Do not raise volume aggressively or interpret an out-of-range result as a hearing or voice diagnosis.

The MIDI number seems unexpected

MIDI is the rounded nearest-note number, not MIDI-device input. Check the selected A4 reference and consider a possible octave error.

The browser reports the microphone is unavailable

Check OS microphone privacy settings, confirm another app does not have exclusive access, and try another supported browser. Do not request camera access.

Related tools

• Tone Generator

  Generate continuous tones or frequency sweeps from 20 Hz to 20 kHz with selectable waveforms and stereo pan—not calibrated SPL or a medical hearing test.

• Microphone Test

  Test a microphone with a live waveform, browser-relative dBFS levels, reported input settings, an optional quiet baseline, and short local playback.

• Vocal Range Test

  Capture stable, comfortable low and high singing notes from local microphone input and calculate the observed span in semitones and octaves—without assigning a medical or professional voice type.

FAQ