Violin Tuner (Viola and Cello Too)
Tune your violin, viola or cello online with the microphone, by ear with bowed reference tones, or from a recording. G D A E at any A4.
Tune a violin (G D A E), viola (C G D A) or cello (C G D A) three ways: let the live tuner listen through your microphone and show how many cents each string is off, play steady bowed reference tones and tune by ear, or check a recording of one string. The reference pitch can be set from 400 to 480 Hz for orchestras that tune to 442 Hz or higher. The sound is analysed in your browser and never recorded or uploaded.
How to use this tool
- Choose the instrument and the mode.
- Live: press Calculate, allow the microphone, and bow or pluck one open string at a time; turn the fine tuner until the bar is centred and green.
- By ear: press Calculate and play each reference tone, then match the string to it.
- Recording: choose "Check a recording", pick a recording of one string and press Calculate.
Formula
f = A4 × 2^((n − 69) ÷ 12) · cents = 1200 × log2(f_played ÷ f_string)
n is the MIDI note number. At A4 = 440 Hz the violin strings are G3 196.00, D4 293.66, A4 440.00 and E5 659.26 Hz; the viola adds C3 130.81 Hz in place of the E; the cello is an octave below the viola: C2 65.41, G2 98.00, D3 146.83, A3 220.00 Hz. String players usually tune the A first, then the others in fifths. Pitch is measured with the YIN method; within ±3 cents counts as in tune.
Example
An orchestra tuning to A4 = 442 Hz wants the violin's A at 442 Hz and its E at 442 × 2^(7 ÷ 12) = 662.25 Hz. If your A sounds at 440 Hz, it is 1200 × log2(440 ÷ 442) = −7.9 cents: a little flat, so tighten it slightly.
Frequently asked questions
Equal temperament or pure fifths?
This tuner uses equal temperament, like a piano. Many string players tune pure fifths by ear (each about 2 cents wider), so after the A, you may prefer to tune the other strings against it by ear using the reference tones.
Should I use the pegs or the fine tuners?
Fine tuners for small changes (a few cents); the pegs only when a string is far out, turning gently while pushing the peg in. Tune up to the note rather than down to it, so the string holds.
Does it work on a phone?
Yes, in Chrome, Safari, Edge and Firefox. Allow microphone access and hold the phone near the instrument in a quiet room. The microphone turns off when you press Stop tuner or switch to another tab.
Last updated:
Page address with these inputs: https://kakao.mobile/tools/violin-tuner/
Cite or embed this tool
kakaoCalc. (2026, November 8). Violin Tuner (Viola and Cello Too). https://kakao.mobile/tools/violin-tuner/
“Violin Tuner (Viola and Cello Too).” kakaoCalc, 8 Nov. 2026, kakao.mobile/tools/violin-tuner/.