Guitar tuner

How to tune a guitar with a tuner

1. Tap Start tuning and allow the microphone. Hold the phone near the sound hole, or close to the strings if your electric guitar isn't plugged in.
2. Pluck one open string and let it ring. With Auto on, the tuner hears which string it is. Tap a string above to choose it yourself; that turns Auto off. If a string is far off (a new string, or more than two or three frets out), Auto can take it for the string next to it: tap the string by hand, and tap Auto to turn it back on.
3. Read the needle. Left of the middle and “cents low” mean flat: tighten the string. Right and “cents high” mean sharp: loosen it a little past the note, then come back up. On other tuners a ♭ or a light on the left means flat, a ♯ or a light on the right means sharp.
4. Keep it in the middle. At five cents or closer, held there for about half a second, the string gets its tick and the tuner moves on to the next one. When all six are done, check the low E once more.

No microphone, or a loud room? With the tuner stopped, tap a string to hear its note and tune by ear until the wobble between the two sounds stops. A phone's speaker can't play 82 Hz, so on a phone the strings below the open A (the low E, and the lowered low strings of the other tunings) sound an octave higher. The note name is the same.

Standard guitar tuning: E A D G B E

Standard tuning, from the thickest string to the thinnest, is E A D G B E, written EADGBE and also called E standard. The thickest string is the 6th and the thinnest the 1st, so “the high E” is the 1st string: highest in pitch, though it sits lowest when you hold the guitar. To remember the order: Eddie Ate Dynamite, Good Bye Eddie.

At A4 = 440 Hz, equal temperament; the reference switch above moves them all. The two E strings are exactly two octaves apart: 4 × 82.407 = 329.63 Hz.

Neighbouring strings are a fourth apart (five frets), except G to B, which is a major third (four frets). With fourths all the way up, the top string would be an F and the full six-string open and barre chords would need awkward stretches. The one major third makes them easy to finger and puts both outer strings on E, so the low and the high E have the same notes at every fret. The six-string guitar settled on this tuning around 1800; the five-course guitar before it already had A D G B E.

Which way to turn the pegs

Tightening a string raises its pitch; loosening lowers it. Which way that is depends on the headstock: seen from the front, with three pegs a side the two sides turn opposite ways, and with all six in a row they all turn the same way. Give the peg a quarter turn, pluck, and watch the needle: if it moves the wrong way, turn back. Always finish by tuning up to the note. If a string is sharp, go below it and come back up: from below, the gear and the string end up pulled tight, and they stay. A string tuned down to its note often slips flat a few minutes later.

Then go through all six a second time. Tightening one string pulls the neck forward a little and the others drop a few cents; on a guitar with a floating tremolo the bridge tips with every string you turn, so expect three or four rounds. New strings stretch and keep sliding flat for the first day: tune, lift each string gently away from the fretboard a few times along its length, and tune again, and they settle sooner. Nylon strings on a classical guitar take several days. Tune every time you pick the guitar up.

Alternate tunings: drop D, half step down, DADGAD, open G, open D

The switches above the strings change what the tuner asks for. Each tuning moves only some strings; the rest stay where standard has them.

• Drop D: only the 6th string goes down a whole step, E to D. Power chords become one finger across the three low strings. Foo Fighters' “Everlong” and the Beatles' “Dear Prudence” are in drop D. By ear: the 7th fret of the dropped string matches the open A.
• Half step down (E♭ standard): every string a semitone lower. The shapes stay the same, everything sounds 100 cents deeper, and the slacker strings bend more easily. Jimi Hendrix and Stevie Ray Vaughan played there, and Guns N' Roses recorded “Sweet Child o' Mine” there.
• DADGAD: the 6th, 2nd and 1st strings down a whole step. The open strings ring Dsus4, neither major nor minor, which is why it carries Irish and Scottish tunes. Davey Graham made it known in the early 1960s, after hearing an oud player in Morocco; Jimmy Page used it for “Kashmir”.
• Open G: the 6th, 5th and 1st strings down a whole step, so the open strings ring G major and one finger across any fret is a major chord. Keith Richards plays “Brown Sugar” and “Start Me Up” in open G, usually with the 6th string taken off.
• Open D: the 6th, 2nd and 1st down a whole step and the 3rd down a semitone; the open strings ring D major. A slide and fingerstyle tuning.

D standard, drop C, open E, open C

For any tuning the switches don't have, use the chromatic tuner: it names whatever note you play, so you tune each string to the note in this table.

Open E pulls the 5th, 4th and 3rd strings up, which adds tension to the neck; many players tune to open D and put a capo at the 2nd fret instead. Drop C and open C take the 6th string down two whole steps, where a light string flaps and reads flat: a heavier low string helps.

Each tuning has its own page with the tuner set to it, the strings in Hz and how to get there from standard: drop C♯, drop B, drop A, open D minor (DADFAD), open A, C♯ standard, C standard, B standard, A standard, FACGCE (midwest emo) and Nashville tuning.

What tuning did Kurt Cobain play in?

No single one. Early Nirvana liked D standard, and “Blew” ended up in drop C by accident at the 1988 Bleach sessions, when the band, already in D standard, tuned down again. “Smells Like Teen Spirit” is in standard tuning; “Heart-Shaped Box” is in drop D.

Clip-on, pedal, app or online tuner?

A tuner, or tuning device, listens to one note, names the nearest of the twelve and shows how many cents sharp or flat it is; a hundred cents make a semitone. The types differ in what they listen to.

• Clip-on tuner: clamps to the headstock and reads the vibration through the wood, so the band next to you doesn't disturb it. The usual choice for a stage or a rehearsal room.
• Pedal tuner: sits on the floor in an electric guitar's signal chain, reads the cable and mutes the sound while you tune.
• Strobe tuner: a moving pattern that stands still when the note is exact. Used for setting intonation, where a tenth of a cent shows.
• Online tuner or app, like this page: uses the phone's microphone, costs nothing and is always in your pocket, but it hears the room as well. In a quiet room it does the job; in a loud one a clip-on is better.
• Built-in tuner: many acoustic-electric guitars have one in the preamp on the side or in the soundhole; it reads the pickup, like a pedal.

What makes a tuner or app good: it shows cents, not only a light; it has a chromatic mode for any note, not just the six strings; it lets you set A = 440 or 442 Hz; and it has the drop and open tunings you use.

Looking for a guitar tuner app that is free? This page works like one without the download: add it to your home screen and it opens like an app. It is an acoustic guitar tuner through the phone's microphone, and tunes an electric unplugged. This guitar tuner is free, with no ads, no account and nothing to download, on a phone or a laptop. Many tuner apps are free with ads and charge to remove them or for extra tunings. The switch under the needle sets the reference: stay at A = 440 Hz to play with a piano or a recording, take 442 Hz to join an orchestra that tunes there, and 432 Hz if you have chosen it; the 432 Hz tuner explains where that number comes from.

How to tune a guitar without a tuner

Get one string right first, usually the low E: tap the 6th string above, play 82.41 Hz on the tone generator, or take the E from a piano. With an A = 440 Hz tuning fork, tune the high E so its 5th fret (A4, 440 Hz) matches the fork, and work down from there. Then tune each string to the one below it: hold the fret, play both strings, and turn until the wobble between them slows down and stops.

1. 5th fret of the 6th string (A2) = the open 5th string
2. 5th fret of the 5th string (D3) = the open 4th
3. 5th fret of the 4th string (G3) = the open 3rd
4. 4th fret of the 3rd string (B3) = the open 2nd. This is the one people get wrong.
5. 5th fret of the 2nd string (E4) = the open 1st

Harmonics are easier to hear: touch the string over the fret wire without pressing it down, and pluck. The 5th-fret harmonic of each string matches the 7th-fret harmonic of the next string up; for the B, match the open B to the 7th-fret harmonic of the low E. Harmonics give pure intervals, though, and a pure fourth is 2 cents narrower than the guitar's frets, so the error piles up string by string: by the G it is about 6 cents. Check the result with the tuner or with the fretted method above.

Why won't my guitar stay in tune?

• New strings are still stretching (above). Old ones go dull and false and stop holding a note: most players change them every few months.
• The room. Wood and steel move with temperature and humidity. A guitar carried from a cold car into a warm room goes out within minutes: let it warm up in its case, then tune. An acoustic is happiest at about 40 to 55 % relative humidity and room temperature; much drier and the top sinks and the strings go flat, damper and they go sharp.
• The nut. A string that pings while you tune and jumps in steps is catching in its slot. Graphite from a soft pencil in the slot helps; a slot that still binds is a repair-shop job.
• The string or the peg. A string with too few wraps on the post creeps: two or three wraps for a wound string, a few more for a plain one. On a classical guitar the knot at the bridge settles for days. A peg that turns too freely has a screw in its button that sets the stiffness; a rattling peg has a loose nut on the front of the headstock. Snug either a quarter turn, no more.
• A floating tremolo moves all six strings at once; tune in small steps and go round several times.

In tune, but chords still sound wrong: intonation

Tuning sets the open strings. Intonation is whether the frets above them are right as well. Tune a string, then play its harmonic at the 12th fret and the fretted note at the 12th fret: the tuner should read the same for both. If the fretted note reads sharp, the saddle for that string has to move back, away from the neck; flat, toward it. On most electric guitars that is a screw at the bridge. On an acoustic the saddle is fixed, and correcting it is part of a setup. Pressing too hard also pushes notes sharp, most of all on the thin strings and high frets.

Some of it is the system, not the guitar. Frets are equal temperament, and an equal-tempered major third is 14 cents wider than a pure one. In an open G chord the open B string is the third, so it can sound a little high even when every string reads dead on. Some players tune the B a few cents flat for chords; for playing with others, leave it at zero.

Acoustic, electric and classical guitars

All three tune to the same notes, E2 to E4, and this tuner works for each. An acoustic is loud enough for the microphone at arm's length. An unplugged electric is quiet: hold the phone close to the strings, or play through the amp on a clean, low setting, because distortion adds overtones that confuse any tuner. Typical string sets, as of 2026, are .010–.046 for an electric and .012–.053 for an acoustic; a classical guitar takes nylon strings in normal or hard tension. A ukulele is tuned G C E A, the same shape as a guitar's top four strings with a capo at the 5th fret; it has its own ukulele tuner. For other guitars: the bass tuner and the 12-string, 7-string and baritone guitar tuners.

The notes you tuned go into Brumm as a short melody over a beat.