TUNER

Manual

1. What TUNER does

   TUNER listens to your microphone and shows the pitch of the note as a needle, offset in cents. It works for guitar and pretty much any instrument a microphone can pick up.

2. How to use it

   Press "Use microphone", grant permission, and play a note — the note name (C through B), octave, and offset in cents from the reference pitch appear in real time. The closer the needle sits to center, the more in tune the note is.

3. Adjusting the reference pitch (A4)

   The reference pitch (A4) defaults to 440Hz but can be adjusted between 430 and 450Hz — useful for orchestras or classical performances tuned to a reference other than 440Hz.

4. How it works: the pitch detection algorithm

   Pitch detection uses YIN, an algorithm widely used in music information retrieval. It finds the periodic repetition in the waveform and normalizes the result before making a decision, which cuts down on mistaking an overtone for the fundamental note. The detected frequency is then refined further with parabolic interpolation for a more precise reading.

5. Accuracy notes

   Pitch detection is less accurate in noisy environments or when multiple instruments or voices sound at once. Instruments rich in harmonics (some wind instruments, distorted guitar) can occasionally be read an octave off if an overtone is picked up instead of the fundamental. Holding a single, sustained note in a quiet room gives the most stable reading.

6. Use case: tuning a guitar

   Pluck each string one at a time and turn the tuning peg while watching the note name and cents offset. Reading from the later, sustained part of the note — once the pitch has settled — gives the most accurate result.

7. Use case: matching an orchestra or classical reference pitch

   Some orchestras and early-music ensembles tune to a reference other than A4=440Hz (442Hz, for example). Set the reference pitch slider to match the ensemble before tuning, and everything lines up to that reference.

8. How it works: in-browser processing and privacy

   Audio is analyzed in real time inside your browser only; nothing is recorded, saved, or sent anywhere. Using the tuner requires microphone permission from your browser.

9. Limits and troubleshooting

   If microphone permission isn't granted, or another app is currently using the microphone, TUNER can't pick up any sound. Check your browser and OS microphone settings and try again.

10. FAQ

    I granted microphone access but nothing happens.

    Check your browser and OS microphone permission settings, and make sure no other app is currently using the microphone.

    The reading jitters around.

    Right after plucking a string the pitch takes a moment to settle — read it from the later, sustained part of the note.

    Does it work for instruments other than guitar?

    Yes — any single note a microphone can pick up works, including bass, wind instruments, strings, and voice. Instruments rich in harmonics can occasionally read an octave off.

    Is the audio saved anywhere?

    No. Microphone audio is analyzed in real time only — it is never recorded, saved, or sent anywhere.

    Which browsers are supported?

    Any recent browser that supports microphone input (getUserMedia), including Chrome, Safari, and Edge.