How to Tune a Guitar
Tuning takes under a minute once you know the routine. This tuner listens through your microphone, detects the pitch of each string in real time, and shows exactly how far you are from the target note in cents (hundredths of a semitone).
1. Start the tuner and play one string
Press Start Tuning, allow microphone access, and pluck a single string — near the sound hole on acoustic, or with your guitar plugged into a clean amp near the mic for electric. The tuner automatically detects which string you're closest to.
2. Watch the needle and adjust the tuning peg
If the needle leans left, the string is flat — tighten the peg to raise the pitch. If it leans right, the string is sharp — loosen it. Make small adjustments and pluck again after each turn.
3. Finish in tune, then double-check all six
When the needle centers and turns green, the string is within 5 cents — in tune. Tune all six strings, then sweep through them once more: tightening one string slightly bends the neck and can nudge the others.
Guitar String Notes & Frequencies (Standard Tuning)
Standard tuning from the thickest string to the thinnest is E–A–D–G–B–E. These are the exact frequencies the tuner targets, based on A4 = 440 Hz concert pitch:
| String | Note | Frequency |
|---|---|---|
| 6th (thickest) | E2 | 82.41 Hz |
| 5th | A2 | 110.00 Hz |
| 4th | D3 | 146.83 Hz |
| 3rd | G3 | 196.00 Hz |
| 2nd | B3 | 246.94 Hz |
| 1st (thinnest) | E4 | 329.63 Hz |
Alternate Tunings
Beyond standard tuning, this tuner has presets for the three most popular alternate tunings — pick one from the dropdown and the string targets update automatically. For anything else, use Chromatic mode, which simply shows the nearest note to whatever you play.
Drop D
Drop only the 6th string from E2 down to D2. The go-to tuning for rock and metal riffs — power chords become one-finger shapes, and the low D adds weight. Fastest of all retunings: one string, one whole step.
Half-Step Down (Eb Standard)
Every string down one semitone: Eb–Ab–Db–Gb–Bb–Eb. Loved by singers because it eases vocal range, and by players for the slightly looser, warmer string feel. Used by Hendrix, Guns N' Roses, and countless others.
DADGAD
D–A–D–G–A–D turns the open strings into a rich suspended chord. A staple of Celtic, folk, and acoustic instrumental playing — melodies ring over open drone strings. Note the three D strings sit in three different octaves; the tuner tells them apart automatically.
Tuning Tips
Tune up to pitch, not down
If a string is sharp, loosen it below the target and then tighten up to it. The last peg movement should always raise the pitch — it keeps the string from slipping flat while you play.
New strings drift — retune often
Fresh strings stretch for the first few hours of playing. Retune every few songs at first, and gently pre-stretch new strings by pulling them lightly away from the fretboard.
Let the note ring cleanly
Pluck one string at a time with a medium attack and let it sustain. Muted, buzzing, or double-struck notes are harder to detect. In a noisy room, move closer to the microphone.
Check your tuning environment
Temperature changes detune guitars fast — a guitar from a cold car needs 15 minutes to settle. And if you tune with the band, make sure everyone uses the same reference pitch (A4 = 440 Hz).
Frequently Asked Questions
How accurate is this online guitar tuner?
The tuner analyzes your microphone signal with the YIN pitch-detection algorithm — the same family of algorithms used in professional tuner apps — and displays deviation in whole cents. In a reasonably quiet room it reliably resolves to within a few cents, which is tighter than most players can hear. A string is marked in tune within ±5 cents of the target.
Why does my guitar keep going out of tune?
The usual culprits are new strings that haven't finished stretching, temperature and humidity swings, aggressive playing or bending, and slipping tuning pegs. Old, corroded strings also hold pitch poorly. If one string constantly drifts, check that it's wound neatly around the post with 2-3 wraps and seated properly in the nut.
Can I use this tuner without a microphone?
Yes. Every string has a reference-tone button (🔊) that plays the exact target pitch through your speakers — tune by ear by matching your string to the tone until the 'beating' between the two sounds disappears. Microphone mode is more precise, but reference tones work anywhere.
What is 440 Hz and why does it matter?
A4 = 440 Hz is the international standard concert pitch — the A above middle C vibrates 440 times per second, and every other note is defined relative to it. This tuner uses 440 Hz, matching pianos, keyboards, and virtually all modern recordings, so you'll be in tune with other instruments and backing tracks.
Does the tuner work for electric, acoustic, and bass guitar?
Acoustic and classical guitars work great straight into the mic. For electric guitar, play near the microphone unplugged, or mic a clean amp. The four guitar presets cover the standard six-string range; for bass guitar use Chromatic mode — it shows the nearest note for any pitch your microphone picks up clearly.
In tune? Keep the practice going
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