12NOTEZ · Free Tool
Tune your cello with your mic — Standard — C G D A (perfect fifths). Free, accurate, private.
Your audio never leaves your device — detection runs entirely in your browser.
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The cello is tuned in perfect fifths, C G D A, one octave below the viola. Start with the A string at 220 Hz, then tune downward through D, G and the low C.
C2G2D3A3
| Tuning | Notes |
|---|---|
| Scordatura | Some solo repertoire retunes the C string for extra resonance |
Switch the instrument selector above to chromatic mode to tune to any of these notes by ear.
Standard cello tuning is Standard — C G D A (perfect fifths) — strings C2, G2, D3, A3 from lowest to highest.
Allow mic access and bow the A string — match A3 (220 Hz). Tune D3, then G2, then the low C2. Match each string to the needle until it reads in-tune (green).
From low to high, the strings are C2, G2, D3, A3.
Yes — this tuner uses your device microphone with cents-precise pitch detection, runs entirely in your browser, and your audio never leaves your device.
Prefer to set tempo instead? Try the free online metronome, or find any song's key in our database.