Don's Tools · Audio · Instrument Tuner

Instrument tuner

Tune your instrument by ear and eye, right in your browser. Your microphone audio stays on your device.

Instrument
A4
––
-50 flat0+50 sharp
Press start and play a note
Private by design: the tuner listens through your microphone and figures out the pitch on your device. The audio is never recorded or uploaded. For the steadiest reading, play one clear note at a time in a quiet spot near the mic.
Instrument Tuner is a free chromatic tuner that runs entirely in your browser, using your microphone to detect pitch on your device with nothing uploaded. Press start and play a single steady note: it shows the nearest note name and octave, the detected frequency in hertz, and how many cents flat or sharp you are on a live meter, turning green when you are in tune. It works for guitar, bass, ukulele, violin, piano, wind instruments and voice, can show an instrument's open strings and highlight the one you are closest to, and lets you set the A4 reference to 432, 440, 442 or 444 hertz.

Files are processed in your browser and never uploaded.

How to use Instrument tuner

  1. Open the page

    There is nothing to fill in. The full list is rendered as soon as the page loads.

  2. Find your entry

    Scroll to the section you need.

  3. Keep it to hand

    The page is plain static HTML, so it still works if you lose your connection after loading it.

What this tool does

Chromatic tuner for any instrument

Chromatic mode detects whatever note you play, so it works for any instrument rather than a fixed set of strings.

Live note, frequency and cents readout

The note name, the exact frequency in hertz and how many cents sharp or flat you are all update live as the note sounds.

Guitar, bass, ukulele and violin string guides

Guitar, bass, ukulele and violin have their string guides, so you can tune string by string without knowing the note names.

Adjustable A4 reference

The A4 reference can be set to 432, 440, 442 or 444 Hz, for orchestras and ensembles that do not use concert 440.

Works entirely on your device, no upload

The microphone audio is analysed on your device and never recorded or uploaded.

Frequently asked questions

Is my microphone audio sent anywhere?

No. The tuner listens through your microphone and works out the pitch entirely in your browser on your device. The audio is never recorded or uploaded, and nothing leaves your device.

What instruments does it work with?

It is a chromatic tuner, so it finds the nearest musical note for almost any pitched instrument: guitar, bass, ukulele, violin, piano, wind instruments and voice. Pick an instrument to also see its open strings and which one you are closest to.

How do I use it?

Press start and allow microphone access, then play a single steady note. The big letter shows the nearest note, and the meter shows whether you are flat (left) or sharp (right). Tune until the needle sits in the green middle.

What does the cents number mean?

Cents measure how far you are from the exact note. There are 100 cents between two adjacent notes, so 0 cents is perfectly in tune. Within about 5 cents is generally considered in tune by ear.

What is the A4 reference for?

A4 is the tuning standard, normally 440 Hz. Some orchestras and styles tune slightly higher or lower, so you can switch to 432, 442 or 444 Hz and every note will shift to match.

It is jumpy or not detecting. Any tips?

Play one clear note at a time in a quiet room, close to the microphone. Background noise, very low or very high notes, and quiet sounds are harder to read. Turning off keyboard or fan noise and getting closer usually helps a lot.

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