Luthieria · 12 October 2026

Why does my guitar go out of tune? Causes and fixes

You tuned the guitar, played two chords, and it is already out of tune again. Or the open strings are perfect, but a chord up the neck sounds off. These are two different problems with different causes, and most of them can be sorted with a few minutes of attention. This guide helps you work out which one you have, what you can do at home, and when it makes sense to take the guitar to a luthier.

First, tell the two symptoms apart

• The guitar drifts out of tune over time or while you play: the cause is almost always the strings, tuners, nut, bridge or environment. Each is fixed differently.
• It is in tune open but goes out of tune up the neck: this is an intonation problem, meaning the effective length of each string. Tuning more carefully will not fix it.

To test it: tune the open string accurately, then compare it with the harmonic at the 12th fret and with the fretted note at the same fret. If they differ, it is an intonation problem.

New strings, wraps and tuners

Newly fitted strings stretch over the first few days, and the tuning keeps falling. It helps to stretch them in gently: tune up, pull each string softly upwards around the middle of the neck, and retune. Repeat a few times. Do not overdo it — the aim is to settle the string, not to force it.

How you fit them matters too:

• Use few wraps on the post, but not just one. As a rule, two to three wraps on the thin strings and one to two on the thick ones.
• Wraps should sit neatly from top to bottom, without crossing. On non-locking tuners, a small kink or tuck in the string end helps it grip.
• Trim the excess after tuning.

If the strings are fitted well and still slip, test the tuners: turn the knob and check that the post responds immediately, with no slack. If the knob turns a bit "empty", or the string creeps back over time, the tuner may be worn. Some models have a small screw at the base of the knob you can tighten, gently. If the slack is internal, the fix is to replace them.

The nut gripping the strings

If you hear a "ping" when tuning, or the string suddenly jumps up past the note, it is likely sticking in its nut slot. The tension then releases all at once, and your tuning shifts, especially after bends or tremolo use.

A simple, safe trick: with the string slackened, rub pencil graphite (a soft pencil, such as 2B) into the slot. Refit the string, retune and see whether the ping is gone. If it persists, the slots may be badly cut, too narrow or have burrs — that is luthier work, since the right depth and width make all the difference.

Floating bridges, tremolo and Floyd Rose

On guitars with a tremolo, such as Stratocasters, any movement of the bridge affects every string at once. If you tune one string and the others go flat, the bridge is moving.

• Check that the springs at the back are properly set and the bridge is balanced (floating or flat to the body, depending on how the guitar is set up).
• New strings, a different gauge or a change of tuning upset the balance, and it needs rebalancing.
• On a Floyd Rose, the locking nut must be clamped after tuning, and fine tuning is done with the bridge fine tuners. Floyds need careful setup: if you are not comfortable, do not improvise.

If you changed gauge recently, also read our article on heavier string gauges and setup.

Temperature, humidity and the neck

Sudden changes in temperature and humidity — a car trip, a stage with air conditioning or lights, winter heating — make wood and strings move. It is normal for a guitar to need retuning after going from cold to warm: let it acclimatise in its case for a while before opening it.

If, even when stable, the guitar keeps having the same tuning problem, the neck may be moving (the truss rod balances string tension). Consider this a heads-up only: do not make big adjustments unless you know what you are doing. If you suspect it, show the guitar to a luthier.

Technique: what your hands do also matters

• Pressing too hard pushes the string sharp. Try easing off.
• Repeated bends stretch the string and can upset tremolo and nut.
• Always tune up to the note: if you overshoot, drop a little and come back up. That keeps the tuner gear tight and stable.
• Use the tuner with the string played normally, without attacking it hard: right after the pick attack the note is slightly sharp, then settles.

Intonation: in tune open, out of tune on the neck

Have you done the 12th-fret test? If the fretted note sounds sharper than the harmonic, the string is too short and the saddle (the bridge piece the string rests on) should be moved away from the neck. If it sounds flatter, the string is too long and the saddle should move towards the neck.

Make small adjustments at a time, slackening the string if needed, then retune and compare again. Old strings fool this test, so change them first. If the guitar has very high action, a misaligned neck or worn frets, intonation will not come right with the saddles alone — that is when a full setup is due.

When to see a luthier

• You hear a nut "ping" and graphite did not help.
• The tuners have slack, or tuning will not hold even with new, well-fitted strings.
• The floating bridge or Floyd will not return to pitch after a tremolo dive.
• Intonation will not come right on all strings.
• You suspect the neck is moving or the frets are worn.

In a guitar setup we deal with exactly this: nut, tuners, bridge, neck and intonation, adjusted to how you play. If the problem comes with buzzing, see our article on fret buzz. You can book your setup here.

And if you are thinking of changing guitars, the used instruments at /#instrumentos always come already evaluated and set up — ready to play and to hold their tuning.

Cover image: Gavin Tapp via Flickr (CC BY 2.0).

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