Viola Tuner Online
Use this free viola tuner online with microphone pitch detection for standard CGDA strings, Open C, Open G, and more viola tunings.
Standard Viola Tuning: CGDA
The standard viola tuning is C3, G3, D4, and A4 from the lowest string to the highest. Use the microphone tuner above to tune each viola string to its target note.
- C string
- C3
- G string
- G3
- D string
- D4
- A string
- A4
Viola Tunings
Choose from 6 popular viola tunings. Each tuning page includes a pre-configured tuner and information about when to use it.
How to Tune a Viola
Tuning your viola is essential for producing beautiful music. This viola tuner online is set up for standard C-G-D-A tuning (from the lowest string to the highest). The strings are tuned in perfect fifths, which is the interval that defines the string family's characteristic sound. The viola is pitched a perfect fifth below the violin, giving it a rich, warm alto voice.
Begin by tuning the A string to A4 (440 Hz), which is the standard concert pitch. Then tune the D string a perfect fifth below A, followed by the G string a perfect fifth below D, and finally the C string a perfect fifth below G. Fine tuners on the tailpiece allow for small adjustments, while the pegs are used for larger changes.
How to Use This Viola Tuner
- Select your tuning from the dropdown menu (Standard CGDA is selected by default).
- Click the microphone button and allow microphone access when prompted.
- Bow or pluck a single string on your viola. The tuner will automatically detect which string you're playing.
- You can also tap a specific string button to tune that string. The tuner will show how sharp or flat you are from the target note.
- Turn the fine tuner or peg until the indicator is centered and the status shows "In Tune."
- Repeat for each string until your viola is fully in tune.
Understanding Viola Tuning
Standard (CGDA) — The universal tuning for viola, with strings tuned in perfect fifths: C3, G3, D4, A4. This tuning is used in classical, orchestral, chamber music, and virtually all other viola genres. The viola sits a perfect fifth below the violin in pitch.
Open C (CGCG) — An open tuning that produces a C power chord when all strings are bowed open. Used in experimental and contemporary viola music, the paired octaves create strong resonance for drone-based compositions.
Fiddle (GDAE) — Viola tuned to violin intervals, a perfect fifth higher than standard. Used by violists who want to play fiddle tunes at violin pitch or explore the higher register of the instrument.
Viola Tuner Online FAQ
Can I use this viola tuner online for free?
Yes. ViolaTuner.io is a free viola tuner online that runs in your browser. Click the microphone button, allow mic access, and tune standard CGDA strings without downloading an app.
What notes are standard viola tuning?
Standard viola tuning is C3-G3-D4-A4, usually written as CGDA from the lowest string to the highest. The strings are tuned in perfect fifths.
Can this tuner hear viola strings through my microphone?
Yes. The tuner listens through your device microphone, detects the pitch of the string you play, and shows whether it is sharp, flat, or in tune.
How do I tune a viola?
Select Standard CGDA, start the microphone tuner, then bow or pluck one string at a time. Adjust the fine tuner or peg until the indicator is centered for C3, G3, D4, and A4.
Is viola tuning the same as violin tuning?
No. Viola tuning is C3-G3-D4-A4, while violin tuning is G3-D4-A4-E5. The viola has a low C string instead of the violin's high E string.