How to tune a guitar

Standard tuning: E A D G B E

Almost every song, chord chart and lesson assumes standard tuning: from the thickest string to the thinnest, E2, A2, D3, G3, B3, E4. The numbers are octaves: the low E is the E two octaves below the high E. Tuning means turning each peg until its string plays exactly its note. Tighten the string and the note goes up; loosen it and the note goes down.

Before you start, find which way each peg turns. Pluck a string, turn its peg a little and listen: if the note rises, you are tightening. Turn slowly, a quarter turn at most at a time, and keep the string ringing while you turn so you can hear the change. A string tuned far too high can break.

Tuning with a tuner

A tuner listens to one string and tells you how far it is from the nearest note. The online guitar tuner uses your computer or phone microphone; a clip-on tuner clamps to the headstock and feels the vibration through the wood, which works even in a noisy room. Either way, the method is the same:

• Pluck one open string firmly and let it ring.
• Check the note name first. If the tuner shows D♯ for your low E, the string is too low: tighten it until the name changes to E.
• Then watch the needle: left of centre is flat, too low, so tighten; right of centre is sharp, too high, so loosen. Stop when it sits in the middle.
• Go through all six strings, then check them all again: the tension of one string slightly bends the neck and moves the others.

Tuning by ear: the fifth-fret method

With no tuner, you can tune the strings to each other. Each string is five half steps above the one before it, except one pair, so the 5th fret of a string plays the same note as the next open string. Start from a low E you trust - a tuner, a piano, or the reference note of the online tuner - and work up:

• Play the 5th fret of the low E, then the open A string. Turn the A peg until they sound the same.
• 5th fret of A against the open D, then 5th fret of D against the open G.
• 4th fret of G against the open B. G to B is four half steps, a major third, where every other pair is five, a perfect fourth: that is why this one fret is different.
• 5th fret of B against the open high E.

The guitar ends up in tune with itself, even if the starting E was a little off. That is fine when you play alone; to play with others or with a recording, start from a reference note.

How to hear that two notes match

Play the two notes together and let them ring. When they are close but not equal, you hear a slow wobble in the volume, called beating: the closer the notes, the slower it gets, until it disappears when they match. If you cannot tell which string is higher, loosen the one you are tuning until it is clearly too low, then bring it up slowly. Always finish by tuning up to the note: the string settles and holds its pitch better than when you tune down.

Why guitars go out of tune

New strings stretch for the first days and keep going flat; retune them often, or gently pull each string away from the fretboard a few times to settle it. Temperature and humidity move the wood and the metal, so a guitar brought from a cold car into a warm room will drift for a while. Bumps, strong bends and heavy strumming do the rest. That is why players tune every time they pick the guitar up, and check again between songs.

Other tunings

Some songs use another tuning. Drop D lowers only the low E to D, for heavier riffs and easy power chords with one finger. Half step down lowers every string by a half step, E♭ A♭ D♭ G♭ B♭ E♭, a classic of rock. Open G (D G D G B D) and DADGAD are folk and slide tunings where the open strings form a chord. The online tuner and the guitar on this page have all of them; this course uses standard tuning throughout.