Music / 02
Guitar Tuner, with Bass, Ukulele, and Violin
Tune a guitar, bass, ukulele, violin, viola, or cello with your microphone, or any instrument in chromatic mode, with a needle in cents, the string you are playing, and a reference note for each string.
Guitar Tuner, with Bass, Ukulele, and Violin: The page listens through your microphone and finds the pitch with the YIN algorithm, which looks for the repeating period of the sound, so it names the fundamental note rather than an overtone. It shows how many cents, hundredths of a semitone, the note is from the nearest string of your tuning, or from the nearest note in chromatic mode, measured from A4 = 440 Hz unless you change it. Runs 100% locally in your browser with zero server file uploads.
- Category
- Everyday tools
- Runs
- In your browser
- Cost
- Free · no sign-up
- Availability
- Ready to use
Runs entirely in your browser
Press Start and allow the microphone.
Press a string to hear its note.
Tuning up, not down
If a string is sharp, loosen it until it is below the note, then tighten it up to pitch. A string tuned up to the note holds better, because the slack in the gears and at the nut is taken up in the direction the string pulls. Retune each string once more after a first pass, since changing one string's tension slightly moves the neck and the others.
New strings stretch for a day or two and go flat again and again; gently pulling each one away from the fretboard along its length, then retuning, settles them faster.
Reading the needle
A cent is a hundredth of a semitone. The display says In tune within 5 cents, a common tolerance for tuners, and shows the exact offset so you can go closer. If the open strings are in tune but notes fretted higher up the neck read well sharp, the cause is usually the instrument rather than your tuning: high action or intonation, which a setup at a guitar shop can fix. The metronome keeps time once you are in tune.
How to use it
- Choose your instrument and press Start, then allow the microphone.
- Play one string at a time and let it ring.
- Turn the peg until the needle is in the centre and the display says In tune.
Privacy & limitations
The sound from your microphone is analysed in your browser and never recorded or sent anywhere. The microphone turns off when you press Stop or leave the page.
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Frequently asked questions
What are the notes of standard guitar tuning?
From the thickest string to the thinnest: E2, A2, D3, G3, B3, and E4, which are 82.41, 110, 146.83, 196, 246.94, and 329.63 Hz at A4 = 440 Hz. Drop D lowers the thickest string a whole tone to D2.
Why does the tuner jump between notes?
Pluck one string at a time, a little firmly, and let it ring without touching the others. The first moment of a pluck is noisy, so the reading settles after a fraction of a second. A quiet room and a phone or laptop held close to the instrument help.
What does A4 = 440 Hz mean, and should I change it?
It is the reference pitch the other notes are worked out from, and the modern standard. Change it only to match a piano or a group tuned differently, such as 442 Hz, which some orchestras use.
Why is the ukulele's first string higher than the second?
Standard ukulele tuning is re-entrant: the G string nearest your chin is tuned to G4, above the C4 string next to it. The tuner expects that high G.
Free tool · runs in your browser · no account required