Tuning · Intonation
Violin Tuner
Two tools on one page: the tuner walks you through G / D / A / E one string at a time — stop when the needle stands in the middle; free intonation practice measures whatever you play. For rhythm, use the metronome link at the top.
Click “Start microphone” first — the browser asks once, then never again. Keep the mic 0.5 to 1 m from the violin.
How to use
Click “Start microphone” first — the browser asks once, then never again. Keep the mic 0.5 to 1 m from the violin.
Tuner: one string at a time
The tuner is the default mode. Pick a string from the pegs below (A is selected, because violinists tune A first and match the rest to it), play the open string, and stop when the needle centres and the panel reads “In tune”. It will not advance on its own — all four strings keep their own state, so start wherever you like.
The tuner judges more strictly than free practice: ±5 cents, held for half a second. That is deliberate — open strings are the reference for every other note, so a few cents off here puts the whole instrument off.
Free intonation practice: play anything
Free intonation practice is pure listening: no target is set, it measures whatever you play — useful for checking a long note or a single phrase. To work through scales and arpeggios by key, use the tool on the home page: pick a key, then “Play along”, and it checks you note by note.
Scales & fingerings Violin sheet music First-position fingering chart
How to read the tuner needle
- Green zone (±10 cents, ±5 in tuner mode)In tune. The ear can barely tell the difference here, so there is nothing more to adjust.
- Yellow (10–25 cents)Slightly high or low: shift the finger a little, or nudge the peg.
- Red (beyond 25 cents)Clearly sharp or flat — it will sound sour.
- Needle turns greyNo usable pitch: too quiet, too short, or not the string currently selected.
Frequently asked questions
Why only the four open strings?
Open strings are the reference for the whole instrument. Get G / D / A / E right and every other note follows from finger placement; get them wrong and nothing you finger will be in tune.
Why is the tuner stricter than free practice?
Tuning is measured against a reference: five cents off affects every note, so it is held to ±5 cents. Free intonation practice looks at the overall accuracy of a passage, where ±10 cents is what the ear accepts in normal playing.
The needle says sharp or flat — which way do I turn the peg?
Sharp: turn the peg outward (loosen). Flat: turn it inward (tighten). Move in very small steps and play the open string again between adjustments — turning too far at once snaps strings, especially the E.
Should A4 be 440 or 442?
440 Hz is the international standard and what most situations use; 442 is used by some European orchestras. Match your teacher or orchestra — you can switch it in the top right.
Does it work on a phone?
Yes, in Chrome and Safari. You need to allow microphone access (the page must be https, which it is). Keep the phone 0.3–0.6 m from the violin rather than right against the f-hole, which clips.
Do I need to tune every time?
Once on the A string before practising is usually enough. Run all four when the temperature has changed (coming in from outside, say); new strings drift for the first week, so check more often.
Is it free? Is my audio uploaded?
Everything is free and there is no sign-up. Microphone audio is analysed locally in the browser for pitch and is never sent to a server.