Cello Tuner
← All toolsA cello is tuned in fifths like a violin but far lower: C2 65.41 Hz, G2 98.00 Hz, D3 146.83 Hz and A3 220.00 Hz. Those are the same four letters a viola uses, sounding an octave beneath it. Tap a string in the chart to hear the pitch, or allow the microphone for live detection — the window it analyses lengthens for the C string, which is the only way a 65 Hz fundamental resolves cleanly.
Microphone audio is processed entirely in your browser and never uploaded.
Cello — Standard (CGDA)
| String | Note | Frequency | Reference tone |
|---|---|---|---|
| 4th | C2 | 65.41 Hz | |
| 3rd | G2 | 98.00 Hz | |
| 2nd | D3 | 146.83 Hz | |
| 1st | A3 | 220.00 Hz |
Tap Tone to hear a string and tune to it by ear — no microphone needed. Auto is on, so the needle below follows whichever string you are nearest.
Live pitch — microphone
Microphone audio is processed on-device and never leaves your browser — and the chart and reference tones above never need it at all.
How to use the Cello Tuner
- Sit with the cello in playing position before you start, since the pegbox ends up behind your left ear and you will be reaching for it blind.
- Set A3 220.00 Hz first, then D, then G, then C, tuning each string as a fifth below the one above it.
- Use the fine tuners on the tailpiece for small corrections and the pegs only when a string is more than a quarter tone out.
- Bow each string with a long, even stroke and read the pitch from the middle of the stroke rather than the attack.
Tuning from the playing position
Unlike a guitarist, you cannot see what you are doing. The pegbox sits above and behind your left shoulder while the tailpiece is between your knees, so the ergonomics of the two adjusters differ completely: fine tuners are in front of you and can be turned while you bow, pegs cannot.
That dictates an order. Get every string within reach of its fine tuner using the pegs, one at a time, with the instrument held steady and your left hand pushing the peg inward as it turns. Then sit properly, bow, and finish at the tailpiece while listening.
Keep the fine tuners near the middle of their travel. Run one to the bottom of its thread and you lose the ability to correct downward halfway through a rehearsal, and a screw driven too far can end up touching the belly of the instrument through the tailpiece.
The low C and what makes it awkward
Every difficulty on the C string traces back to 65.41 Hz being a slow wave. One cycle lasts about 15 milliseconds, so the tuner needs a longer stretch of continuous audio before it can measure a period at all, and you notice that as a reading which takes a beat to settle. Bow through it rather than stopping to look.
The string itself carries the most mass and the most winding on the instrument. It responds slowly to the bow, its fundamental is quieter than the harmonics stacked above it, and a heavy bow arm will drag the pitch flat at the exact moment you are trying to measure it. A light, steady stroke near the middle of the bow gives the cleanest reading.
Tune it last, then check A3 220.00 Hz again. Bringing the thickest string up to pitch adds several kilograms of pull across the top and neck, and the other three will have shifted in response.
Cello, and the violin a twelfth above it
The cello's C2 at 65.41 Hz is the lowest open string on this site apart from the bass, and it needs the same long analysis window a bass does. The violin's strings are laid out in the same fifths, an octave and a fifth higher.
| Tuning | Strings, low to high | Frequency (Hz, A4 = 440) |
|---|---|---|
| Cello — Standard (CGDA) | C2 G2 D3 A3 | 65.41 98.00 146.83 220.00 |
| Violin — Standard (GDAE) | G3 D4 A4 E5 | 196.00 293.66 440.00 659.26 |
FAQ
- Why does the C reference tone sound thin on my laptop?
- Because C2 is 65.41 Hz and a laptop speaker cannot move enough air that low. What reaches you is mostly the harmonics above the fundamental, and your ear reconstructs the missing pitch from their spacing — convincing enough to tune to, but weak and easy to mishear by an octave. Headphones or any speaker with a real driver will play the actual fundamental, and the difference is obvious the moment you switch.
- Pegs or fine tuners?
- Fine tuners for everyday work. Most cellos carry four of them, one per string, because the tension involved makes peg work coarse: a few degrees of rotation can move a string most of a semitone. Keep the pegs for restringing or for a string that has dropped badly, and push the peg inward as you turn so it grips. Geared pegs, if your instrument has them, turn like machine heads and hold without pressure.
- How do I check a fifth by ear?
- Bow two adjacent strings together and listen for beating inside the sound. A fifth that is nearly right pulses slowly; as you close in the pulse slows further and stops, and the two notes lock into one steady sound. Bow lightly so both strings speak evenly, adjust only the string you are currently tuning, and work downward from A3 220.00 Hz so your reference is always the string above.
- One note on my cello howls and the tuner cannot read it.
- That is a wolf tone: a note whose frequency coincides with a strong resonance in the body, so the top and the string compete for the same energy and the sound stutters instead of sustaining. It usually lands around E, F or F♯ on the G or C string, and it is a property of the instrument rather than of your tuning. Tune on open strings and other notes, and fit a suppressor to the affected string if it is severe.
