Online viola tuner

Viola string notes

Frequencies are calculated with the reference A at 440 Hz. If your group tunes to a different reference, such as 442 Hz, adjust it with the − and + buttons next to “A = 440 Hz” and the tuner shifts every note.

The viola, the violin and the C clef

The viola shares three strings with the violin, at exactly the same pitch: G3, D4 and A4. Instead of the high E, it has a low C (C3), an octave below middle C. That's why its music is written mostly in alto clef (the C clef on the third line), where the middle line of the staff is middle C.

As on the violin, the strings are a perfect fifth apart. Tune the A first to the 440 Hz reference (or whatever your group uses), then check each pair of neighboring strings by playing them together.

How to tune the viola by ear

First tune the A with the tuner or with your group's reference A; in an orchestra, the viola takes the same A from the oboe as the rest of the strings. Then play A and D together with a long bow and adjust the D until the wavering disappears; continue with D and G, and finish with G and C. The C string responds more slowly: give it a full bow and wait for the sound to settle before deciding whether it's sharp or flat.

Viola sizes

Unlike violins, violas aren't sized in fractions but by body length, in inches or centimeters (for example, 15, 15½ or 16 inches). They're all tuned the same: C, G, D, A. A larger viola usually gives a deeper C, but it demands a longer arm reach and a wider hand stretch.

How to tune your viola with this tuner

1. Tap Enable microphone and accept the browser's permission request. The sound is analyzed on your device: it isn't recorded or sent anywhere.
2. Leave the tuner on Auto so it recognizes which string you're playing, or tap a note to lock it (tap it again to go back to Auto).
3. Play a single open string with medium force and let it ring.
4. If the needle is to the left, the note is flat: tune up. If it's to the right, tune down. Anywhere between −5 and +5 cents counts as in tune.
5. Once a string stays in tune for a moment, its button gets a green check mark. Keep going until every string has one.
6. Use the speaker icon under each note to hear the reference and train your ear.
7. Go over every string again at the end: the tension of some strings shifts the others slightly.

Tips for tuning your viola

• The C string is thick and slow to settle: draw the bow for a long, even sound.
• Use the fine tuners for small adjustments and the pegs only for big changes.
• Check the fifths between neighboring strings by playing them together: when they're in tune, the sound stops 'wobbling'.
• Tune once the instrument has reached the temperature of the place where you'll play; wood and strings react to the weather.

Common tuning problems

• The needle jumps between notes: play a single string, a little more softly, and wait for the sound to settle. The first instant of every note always sounds slightly sharp.
• It doesn't pick up the low strings: phone microphones struggle with low frequencies. Hold your phone closer to the instrument or play the harmonic at the middle of the string (12th fret): the tuner recognizes it as the same string and tells you it sounds an octave higher.
• The open strings are in tune, but what you play sounds off: check that no string is in the wrong octave and that your strings aren't old. If it still sounds wrong, ask your teacher or a luthier to check the instrument's intonation.
• It goes out of tune right away: new strings keep stretching for several days, and changes in temperature and humidity shift the tuning. Tune in the same place where you're going to play.
• The browser doesn't ask for the microphone: check the site permissions in your browser settings and make sure no other app is using the microphone.

Frequently asked questions