Viola and Cello Tuner
C G D A for both; the cello sounds an octave lower.
Violin tuner
The tuner needs JavaScript and a microphone. The note table and frequencies below work without it.
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Or tune by ear with the reference tones, or tap a string button below to hear its note.
A viola is tuned C3, G3, D4 and A4, and a cello is tuned C2, G2, D3 and A3, from the lowest string. Both use the same note names, C G D A, a fifth apart; the cello is one octave lower. Pick Viola or Cello above the gauge and tune the A first.
| String | Note | Hz @440 | Hz @442 |
|---|---|---|---|
| 4 | C3 | 130.81 | 131.41 |
| 3 | G3 | 196.00 | 196.89 |
| 2 | D4 | 293.66 | 295.00 |
| 1 | A4 | 440.00 | 442.00 |
| String | Note | Hz @440 | Hz @442 |
|---|---|---|---|
| 4 | C2 | 65.41 | 65.70 |
| 3 | G2 | 98.00 | 98.44 |
| 2 | D3 | 146.83 | 147.50 |
| 1 | A3 | 220.00 | 221.00 |
Tips
- Tune the A first, then D, G and C.
- Cellos and violas usually have fine tuners at least on the A string; the same rules as on the violin apply.
- For the low C, bow slowly and let the note settle before you read the needle.
Questions and answers
How is a viola tuned?
C G D A, from the lowest string: C3 (130.81 Hz), G3 (196.00 Hz), D4 (293.66 Hz), A4 (440.00 Hz). It has the violin’s top three strings, G D A, and a low C instead of the E.
How is a cello tuned?
C G D A, one octave below the viola: C2 (65.41 Hz), G2 (98.00 Hz), D3 (146.83 Hz), A3 (220.00 Hz).
Can a phone hear the low cello C?
Usually, yes. If the reading jumps, hold the phone closer to the cello and tap the C button to lock the tuner to that string.
More violin tools
- Online violin tunerTune with your microphone
- Reference tonesTune by ear
- How to tune a violinFor beginners
- Fine tuners and pegsWhich to turn, and how
- 1/2 and 3/4 violinsSame notes, smaller size
- A = 440 or 442 HzWhich pitch to use
- Online guitar tunerSister site for guitar
- Online bass tunerSister site for bass
Last updated October 23, 2026.