Microphone tuner
Online tuner
Pick your instrument, press Start and play one string at a time. The mace swings left when you are flat and right when you are sharp.
The tuner finds the nearest string by itself. Tap a string to hear its note and lock onto it; tap it again to go back to automatic.
The sound from your microphone is analysed inside this tab a few times a second. It is never recorded, stored or sent anywhere, and the microphone turns off when you press Stop or leave the page.
How to tune with it
Choose your instrument, press Start tuner and allow the microphone when your browser asks. Play one open string and let it ring. The big letter is the nearest string (or, in chromatic mode, the nearest note), and the needle shows how far off you are in cents, hundredths of a semitone. Within 5 cents the light turns green: close enough that the difference is very hard to hear on a single note.
Tune up to the note rather than down to it: if a string is sharp, slacken it below the note and come back up, so the string settles under tension and stays put. Mute the other strings with your fretting hand so they do not ring along, and pluck at a normal strength; a very hard pluck starts slightly sharp.
A4 reference sets the pitch of the A above middle C. 440 Hz is the international standard; some orchestras tune to 442 or 443, and baroque groups often use 415. Every other note moves with it, using equal temperament: each semitone is the twelfth root of two higher than the last.
Sources
- ISO 16:1975, Acoustics — Standard tuning frequency (Standard musical pitch): A4 = 440 Hz. iso.org/standard/3601
- de Cheveigné A, Kawahara H. YIN, a fundamental frequency estimator for speech and music. J Acoust Soc Am 2002;111(4):1917–1930. doi:10.1121/1.1458024 (the pitch detection method this tuner uses).
- Note frequencies use twelve-tone equal temperament, f = A4 × 2^((n − 69) / 12) with MIDI note numbers n (A4 = 69), and cents = 1200 × log2(f ÷ the note’s frequency).
Questions
Is my microphone audio recorded or uploaded?
No. The browser hands the sound to code running in this tab, which measures the pitch of each short slice and throws it away. Nothing is saved or sent anywhere. Pressing Stop, or leaving the page, switches the microphone off.
The tuner cannot use my microphone. What can I do?
If you blocked the permission prompt, open the site settings from the icon at the left of the address bar, allow the microphone and press Start again. On a computer, also check that the system lets the browser use the microphone, and that another app is not holding it.
Why does the note jump around on a low string?
Low strings are rich in overtones and laptop microphones pick up little of the fundamental. Pluck a little harder, move the instrument closer and choose your instrument rather than chromatic, so the tuner only looks for that instrument's strings.