Guitar Tuner
Standard, drop D, half step down or open G — tuned through your microphone, with the audio analysed on your device and never recorded.
Table of contents
The order you tune in matters more than you would think
A guitar is not six independent strings. Every one of them pulls on the same neck, so tightening the low E bends the neck a fraction and drops the pitch of the five you already did. On a guitar that is badly out, one pass is never enough — tune all six, then go round again, and the second pass will be much smaller than the first.
Always arrive at the note from below. Tuning machines and the winding on the post both have slack in them; coming up to the pitch leaves everything under tension where it will stay, while coming down leaves it loose enough to creep flat over the next few minutes. If you overshoot, drop well below and come back up.
The B string is the one that will annoy you. It sits where the guitar’s equal-tempered compromise is least comfortable, so a B tuned perfectly against a tuner can still sound slightly sour in an open G or D chord. Plenty of players tune it a couple of cents flat by ear afterwards, and that is not a mistake — it is the instrument, not the tuner.
Fresh strings are a separate problem. They stretch for the first hour or so of playing, so a new set will go flat repeatedly no matter how carefully you tune it. Stretch each one gently by hand, retune, and repeat until it stops moving.
Frequently asked questions
Standard — E A D G B E — unless you know otherwise. Drop D lowers only the sixth string a whole tone and is common in rock and folk. Half step down tunes everything a semitone flat, which suits singers and gives a slacker feel. Open G tunes the guitar to a chord itself and is a slide and blues tuning.
Because a plucked low E often has a first harmonic louder than the fundamental, and simpler pitch detection follows the loudest repetition it can find. This tuner divides out the signal's own energy at each candidate period and takes the first that clears a threshold rather than the strongest, which is specifically what stops that octave error.
No. Acoustic or electric, the microphone hears the instrument itself. On an electric, playing unplugged is quieter but perfectly loud enough — hold the guitar within a metre of the device and away from anything humming.
Almost always intonation rather than tuning. Pressing a string to a fret stretches it slightly sharp, and how far depends on the height of the strings and where the saddle sits. If open strings read true but fretted notes at the twelfth fret are sharp, the guitar needs setting up rather than retuning.
Every time you pick it up, and again after a few minutes of playing if the strings are new or the room has changed temperature. Wood and steel both move; a guitar that was perfect last night rarely still is.
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