Online guitar tuner
that runs in your browser.

Standard guitar tuning: the notes and their frequencies

A guitar in standard tuning reads E A D G B E from the thickest string to the thinnest. The two E strings are two octaves apart, which is why the same letter turns up at both ends. Strings are numbered from the thin one: the high E is the first string, the low E the sixth.

Those figures move if you move the reference pitch. Every frequency on this page is quoted at A4 = 440 Hz, and the tuner recalculates all of them the moment you change the slider.

What the needle is measuring

The gap between the note you played and the note you are aiming at is measured in cents — hundredths of a semitone, so a hundred cents to the next fret. Inside five cents the tuner turns green and calls the string in tune, which is tighter than most people can hear on a single note. Between five and eighteen it goes amber and is worth another nudge. Past that it is red and you are closer to a neighbouring note than to a good one.

How to tune a guitar with this tuner

1. Sit somewhere reasonably quiet with the microphone within an arm's length of the instrument. Press Start tuner and allow the microphone when the browser asks.
2. Choose your tuning. Standard is selected unless you change it, and whatever you pick is remembered for next time.
3. Play the low E on its own and let it ring. Do not strum — a chord has no single pitch to lock on to.
4. Read the needle. Left of centre means flat, so tighten; right means sharp, so slacken. The arrow says which way in words as well.
5. Turn slowly. On the thin strings a quarter turn of the peg is most of a semitone, so move in small amounts and let the reading settle.
6. Land inside the green band and the string ticks itself off. Work across the remaining five the same way.
7. Go round all six a second time, because tightening each one has pulled the neck and moved the others.

Always arrive from below

Tune a little flat, then come up to the note. A peg turned downwards leaves slack that the post is holding rather than the nut, and the first bend or hard strum pulls that slack through and drops you flat again. Coming up puts the string under tension against the post, and it stays. If you overshoot, go back under the note and rise to it a second time.

Give the low strings time

The wound E and A move slowly, and their first fraction of a second is a mess of overtones the pitch has not settled into yet. Pluck at normal playing strength, wait for the needle to stop arguing with itself, then adjust. Plucking harder makes it worse rather than clearer, because a hard attack pushes the string sharp before it settles.

Go round twice, or three times

Every string you tighten pulls the neck slightly and detunes the ones you have already done. On a guitar with a floating tremolo it will take three passes, because the bridge itself moves as the tension changes. This is normal and not a fault in the tuner.

Fresh strings will not hold

New strings stretch for the first hour of playing. Tune, play hard for a minute, tune again, and repeat until it stops drifting. You can speed it up by pulling each string gently away from the fretboard a few times and retuning after each pull.

How to tune a guitar by ear

Worth knowing for the day you have no phone. Everything below tunes the guitar to itself, so it is only in tune with the rest of the world if the string you start from is right. Get the low E from this tuner, a piano, or another instrument first.

The fifth-fret method

Fret one string, play it against the next open string, and turn the peg until the wobble between them disappears. That beating slows as the two pitches converge and stops when they match.

The third string is the odd one out because the gap between G and B is a third rather than a fourth. Use the fourth fret there and the fifth everywhere else.

Harmonics, and why they mislead

The old trick of matching the harmonic at the fifth fret of one string against the harmonic at the seventh fret of the next gives you a pure fifth, which is about two cents wider than the tempered fifth a guitar's frets are cut for. Do it across four pairs of strings and the error stacks up to roughly eight cents by the time you reach the top.

The B string is worse. Matching the fourth-fret harmonic of the G against the fifth-fret harmonic of the B is a pure major third, and that sits around fourteen cents below where the frets expect it. Harmonics are useful for checking an octave; they are a poor way to set a guitar up.

Tuning to a piano

The note a piano is set from is A4 at 440 Hz, the A directly above middle C. Your open A string is A2 at 110 Hz, two octaves below it, so match octaves rather than pitches: middle C on the piano is C4, and the nearest guitar note to it is the first fret of the second string. Easier still, switch this tuner to chromatic and tune both instruments to the same reading.

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

Each of these has a preset above, so the tuner knows what note each string should be and lights the right one as you play.

Drop D

Lowers only the sixth string, from E2 at 82.41 Hz to D2 at 73.42 Hz. It puts a power chord under one finger across the bottom three strings and drops the guitar's lowest note by a tone, which is why so much rock and folk lives there. Everything else stays exactly where it was, so your chord shapes above the sixth string are untouched.

Half step down

Every string comes down one semitone, to E♭ A♭ D♭ G♭ B♭ E♭. Singers use it to take the top off a song without learning new shapes, and the slacker strings bend more easily. If you are playing along with a record that sounds a fraction low against your guitar, this is usually why.

DADGAD

D A D G A D, an open Dsus4. Strummed open it rings without being major or minor, which is why it suits modal and Celtic playing and why one finger laid across a fret gives you a usable chord. Three strings move: the sixth down a tone, and the top two down a tone each.

Open G and open D

Both ring out as a full major chord with nothing fretted, which is what slide playing is built on. Open G is D G D G B D, and it is the tuning most associated with five-string playing where the lowest string is taken off altogether. Open D is D A D F♯ A D.

Open E is the same set of intervals as open D but a whole tone higher, which means noticeably more pull on the neck. Most players get there by tuning to open D and putting a capo at the second fret instead.

Anything else

Drop C, open C, Nashville high-strung, seven-string and baritone tunings have no preset here. Switch the tuner to Chromatic and it names whatever note it actually hears instead of trying to match your string to one it expects, which is what you want when the target is unusual. Its range runs from about 29 Hz to 2200 Hz, so it covers everything from a five-string bass low B upwards.

Tuning a twelve-string guitar

A twelve-string is six pairs, called courses. The bottom four pairs are tuned in octaves, the top two in unison, and each string of a pair has its own peg.

Use chromatic mode. The Standard preset only knows the six main notes, so it would try to pull the octave partners towards whichever of those six they happen to sit nearest. Chromatic names each string for what it is and lets you tune all twelve against the table above.

Mute the partner. Two strings ringing together give the tuner two pitches to choose between, and a phantom pitch below both. Rest a finger on the one you are not tuning.

Do the six main strings first, then the octaves. A twelve-string carries close to twice the pull of a six, so the neck moves a long way as you work and an early pass will not survive a later one. Expect three passes rather than two.

Go gently on the octave strings. They are thin plain wire at high tension and they are what breaks. Approach from below, in small turns, and stop the moment the needle sits green.

Plenty of players keep a twelve-string a semitone or a whole tone below standard to spare the top and the neck, and capo back up when they need concert pitch. Tune that the same way, in chromatic, aiming a semitone or a tone below every note in the table.

Bass, ukulele and tenor guitar

Bass

Standard bass tuning is E A D G, an octave below the bottom four strings of a guitar. The low B of a five-string sits near 31 Hz, which is low enough that many phone microphones roll it away entirely. If the reading will not settle down there, play the same string at the twelfth fret and tune the octave — same string, same peg, a pitch the microphone can actually hear.

Ukulele

Standard ukulele tuning is G C E A. On a soprano or concert uke the G is usually re-entrant — tuned high, above the C, rather than as the lowest string. That is not out of tune, it is the sound of the instrument. A low-G set puts it underneath instead, an octave down at 196.00 Hz. Either way the tuner reads the note in front of it, so pick the string you are actually turning.

Baritone ukuleles are tuned D G B E, the top four strings of a guitar. There is no preset for that; chromatic handles it.

Tenor guitar

Four strings tuned in fifths, C G D A — the same intervals as a mandola or a viola, which is why fiddle players take to it quickly. That is C3 at 130.81 Hz, G3 at 196.00 Hz, D4 at 293.66 Hz and A4 at 440.00 Hz. Irish players often use G D A E instead, an octave below a fiddle; use chromatic for that one.

When a string will not hold its pitch

A string that goes flat again a minute after you tuned it is almost never the tuner and almost never the peg. It is slack finding its way out of the system. Work through these in order.

• The strings are new. Steel stretches for the first hour of playing. Tune, play hard, tune again, and keep going until it settles. Nothing else on this list matters until this one is ruled out.
• It pings, then drops. A sharp click followed by a sudden flat note means the string was caught in its nut slot and has just let go. Rub pencil lead into the slot — graphite is a dry lubricant — or use proper nut sauce. This is the single most common cause on a guitar that holds tune everywhere except after a bend.
• The winding is slipping at the post. You want two or three neat turns on the thick strings and three or four on the thin ones, wound downwards towards the headstock, with the string end trapped under its own first wind. Windings that cross over each other slide.
• The ball end is not seated. On an acoustic, a bridge pin that has not pulled the ball end up against the bridge plate will creep for days. On an electric, check the string is sitting properly in the ferrule or through the tailpiece.
• The tuning machine is loose. If the button turns with no resistance, tighten the small screw in the end of it, and check the nut on the face of the headstock.
• You tuned downwards onto the note. Come back up to it instead; the reason is in the section above.
• There is a tremolo. A floating bridge is a balance between string tension and spring tension, so every string you change moves every other one. Three passes, minimum, and if it never settles the spring claw needs adjusting.
• The guitar has just come in from the cold. Wood and steel both move as the instrument reaches room temperature. Give it ten or fifteen minutes before you bother tuning it properly.
• The strings are simply old. Corroded and pitted strings go dead, refuse to hold, and read differently at different points along their length. Change them.

In tune, but the chords still sound sour

If every open string reads green and a first-position chord still sounds wrong, the tuning is not the problem. Three things are usually behind it.

Intonation

Fret the twelfth fret and compare the note with the harmonic at the same fret. They should read the same. If the fretted note is sharp, the saddle for that string needs to move back, away from the neck; if it is flat, it moves forward. That is a setup job with a screwdriver, not something a tuner can fix, and it is why a guitar can be perfectly in tune open and wrong at the seventh fret.

How hard you are pressing

Pushing a string down to the fret stretches it, and stretching it raises its pitch. With a high action or a heavy hand that is easily worth five or ten cents, and it is worse near the nut. Fret with the least pressure that gives a clean note and check whether the chord improves.

Equal temperament

A guitar's frets are cut so that every key is equally slightly wrong, which is the compromise that lets you play in all of them. An open G or an open E chord is usually the casualty. Many players set the B string a couple of cents flat of the tuner to make first-position chords sit better, and accept that everything above the fifth fret gets marginally worse. It is a real trick, not a fault in the reading.

440 Hz, 432 Hz, and what the reference pitch does

A4 = 440 Hz is concert pitch, and effectively every recording you will play along with is at it. If your guitar is in tune with itself but fights the record, check this first: a reference set to 432 leaves you about a third of a semitone flat against everything.

There are honest reasons to move it. A piano that has drifted and cannot be tuned before rehearsal, an orchestra sitting at 442, or early-music instruments at 415 — a semitone below modern pitch — all call for it. The slider here covers 415 to 466 Hz, and the tuner recalculates every target frequency as you move it.

There is no acoustic evidence for the claims made about 432 Hz being more natural or better for you, and we would rather say so than sell you a setting. It is here because some players genuinely need to move the reference, not because the number does anything to the music.

Your choice is remembered in this browser, so it will still be set the next time you open the tuner. If the chip beside the meter is amber, you are not at concert pitch — that is the warning, and Back to 440 undoes it.

Questions

Is this guitar tuner free?

Yes. The tuner is free with no account, no sign-in and no limit on how often you use it. It is a single web page, so there is nothing to install.

Does it work on a phone?

Yes. It runs in the browser on Android and iOS as well as on a laptop. Prop the phone up facing the guitar, allow the microphone when asked, and it behaves exactly as it does on a desktop.

Is my audio recorded or uploaded?

No. Pitch detection runs on your own device and nothing is recorded, stored or sent anywhere. The microphone is released the moment you press stop, or leave the page, or switch to another tab.

How accurate is it?

It resolves to the cent, and it refuses to show a reading it is not confident about rather than guessing. Measured against generated tones and synthetic strings, the worst error was under six cents and the typical error around two. On a clean tone from a keyboard it is well under one.

Can I tune an electric guitar with it?

Yes, played acoustically near the microphone — an unplugged electric is quiet but perfectly loud enough. If your audio interface is set as the computer's default input, the tuner will read that instead, so a plugged in guitar works too.

What notes is a guitar tuned to?

E A D G B E, from the thickest string to the thinnest: E2, A2, D3, G3, B3 and E4. At concert pitch that is 82.41, 110.00, 146.83, 196.00, 246.94 and 329.63 Hz.

Can it tune a violin, mandolin or piano?

Switch to chromatic and it will name any note between roughly 29 Hz and 2200 Hz, which covers all three. There are no presets for their strings, so you tune against the note names rather than against a highlighted string.

Why does it say I am sharp when the guitar sounds fine?

Check the reference pitch chip first — if it is amber, the tuner is measuring against something other than 440 Hz. After that, check the octave shown next to the note letter, in case you are reading a harmonic rather than the string itself.

How often should I tune?

Every time you pick the guitar up, and again after twenty minutes of hard playing. Strings drift with temperature, humidity and use, and a new set will drift for its first hour whatever you do.

In tune, then what

Being in tune is the start. If you are learning a song, the studio takes any audio file you own and lays out its chords, key and tempo on a beat-locked timeline, with the shapes for guitar, ukulele or piano moving as it plays. You can drop the key of the recording itself to suit your voice, slow it down without it going sour, and loop the two bars you keep missing.

Open the studio