Precision Musical Instrument Tuner

Free Online Guitar Tuner — Precision Audio & Mic Tuner

Tune your acoustic guitar, electric guitar, bass, or ukulele directly in your browser. Features real-time microphone pitch detection, dynamic tuning needle gauge, and realistic acoustic string plucks. 100% free, responsive for desktop & mobile.

Drop / Capo Transpose:

Standard (0)

Quick Drop:

Ready — Click Start Tuner

—

0.0 Hz Target: Pluck any string

0 cents

Mic:

Instrument Strings & Tone Pluckers

Click any string card to lock or play acoustic reference pluck

Instrument & Tuning Preset:

Concert Pitch Calibration (A4):

Auto-Detect String

Continuous Reference Drone

Space Start / Stop Mic 1 to 6 Pluck String A4 440 Hz Standard

GUITAR TUNING REFERENCE

Standard Guitar Tuning Frequencies Chart (E A D G B E)

Precise scientific pitch notation, fundamental acoustic frequencies, and recommended string gauges calibrated to international concert pitch (A4 = 440 Hz)

String	Note Name	Scientific Pitch	Target Frequency	Wavelength (Air)	Typical Gauge
String 6 (Thickest)	Low E	E2	82.41 Hz	4.16 m	.046 – .052 (Wound Bronze / Nickel)
String 5	A	A2	110.00 Hz	3.12 m	.036 – .042 (Wound)
String 4	D	D3	146.83 Hz	2.34 m	.026 – .032 (Wound)
String 3	G	G3	196.00 Hz	1.75 m	.016 – .017 (Plain or Wound)
String 2	B	B3	246.94 Hz	1.39 m	.011 – .014 (Plain Steel)
String 1 (Thinnest)	High E	E4	329.63 Hz	1.04 m	.009 – .010 (Plain Steel)

ALTERNATE TUNINGS COMPASS

Popular Alternate Guitar Tunings Reference

Open chords, modal drones, and heavy drop tunings for acoustic, rock, blues, and fingerstyle guitarists

Tuning Name	String Sequence (6 to 1)	Root Key	Common Genres	Notable Artists / Songs
Drop D	D2 – A2 – D3 – G3 – B3 – E4	D Minor / Major	Hard Rock, Metal, Grunge, Blues	Nirvana, Soundgarden, Foo Fighters
DADGAD (Celtic)	D2 – A2 – D3 – G3 – A3 – D4	D Modal (Dsus4)	Celtic, Folk, Fingerstyle, Acoustic	Jimmy Page (Kashmir), Pierre Bensusan
Half Step Down (Eb)	Eb2 – Ab2 – Db3 – Gb3 – Bb3 – Eb4	Eb Standard	Classic Rock, Blues Rock, Grunge	Jimi Hendrix, Stevie Ray Vaughan, Guns N’ Roses
Open D	D2 – A2 – D3 – F#3 – A3 – D4	D Major	Delta Blues, Slide Guitar, Folk	Bob Dylan, Elmore James, Joni Mitchell
Open G	D2 – G2 – D3 – G3 – B3 – D4	G Major	Blues, Classic Rock, Slide	The Rolling Stones (Keith Richards), Muddy Waters
Drop C	C2 – G2 – C3 – F3 – A3 – D4	C	Metalcore, Post-Hardcore, Modern Metal	Deftones, Slipknot, Bullet for My Valentine
4-String Bass Standard	E1 – A1 – D2 – G2	Standard Bass	All Musical Genres	One octave lower than guitar strings 6 to 3

PRACTICE & TECHNIQUE GUIDE

How to Tune Your Guitar Accurately: Step-by-Step Guide

Master both microphone pitch detection and traditional tuning by ear

1. Position Your Device & Isolate Background Noise

Place your smartphone, laptop, or tablet roughly 6 to 12 inches from the acoustic guitar soundhole or electric guitar amp. Minimize background television, chatter, or fans so the condenser microphone captures pure acoustic string vibrations.

2. Tune From Low Strings to High Strings (Neck Relief Balance)

Always tune the thickest 6th string (Low E) first, then proceed through A, D, G, B, and High E. Guitar necks withstand over 150 lbs of overall tension; tuning heavy strings first establishes correct truss rod counter-tension so lighter strings stay stable.

3. Pluck Near the 12th Fret with Your Thumb Pad

Guitars naturally produce strong octave overtones. Plucking gently near the 12th fret with your thumb pad dampens harsh metallic upper harmonics and accentuates the fundamental pitch (f0), giving the pitch detection algorithm a rock-solid lock.

4. Always Tune UP Into the Pitch (Eliminate Peg Backlash)

If your string is sharp, drop the pitch below the target note, then slowly tune up into the green center zone. Tuning upward keeps the string peg teeth under forward tension and prevents machine head gear slippage during vigorous playing.

5. Verify Intonation at the 12th Fret

Once open strings are in tune, lightly touch string 12 directly above the fretwire to sound an acoustic harmonic, then compare it to the fretted note at fret 12. If the fretted note is sharper than the harmonic, adjust your bridge saddle backward.

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FREQUENTLY ASKED QUESTIONS

Everything You Need to Know About Online Guitar Tuners

Common questions about microphone accuracy, audio pitch detection, and guitar maintenance

How do I drop all guitar strings down by 4 semitones or tune down to A# / Bb?

To drop all strings down equally across the entire instrument, use the Drop / Capo Transpose toolbar directly above the meter. Clicking -4 (C) lowers every string by 4 semitones (transforming Standard E into C Standard: C – F – A# – D# – G – C). If you want E to drop to A# / Bb, that is a drop of 6 semitones (a tritone); click -6 (A#/Bb). You can also click Customize Strings to set any string to any individual note (C, C#, D, D#, E, F, F#, G, G#, A, A#, B) and octave independently.

Why is my guitar tuner jumping between different notes?

Guitars produce natural overtones where the 2nd harmonic (one octave higher) is often louder than the fundamental note. To fix jumpy readings, pluck the string gently near the 12th fret with your thumb pad rather than near the bridge with a hard pick. This emphasizes the fundamental frequency and reduces treble harmonics.

How accurate is this browser guitar tuner compared to a hardware clip-on tuner?

Our online tuner uses sub-sample parabolic autocorrelation running on the Web Audio API at 44.1 kHz / 48 kHz. It measures pitch with sub-Hertz resolution (< 0.1 Hz), achieving accuracy within ±1 cent (well beyond the human ear’s 3–5 cent pitch discrimination threshold), matching professional clip-on pedal tuners.

Can I tune an electric guitar without an amplifier?

Yes! Simply hold your smartphone or laptop microphone directly over the electric guitar’s pickups or upper body wood while plucking. The sensitive condenser microphone will clearly pick up the unamplified string vibrations.

What is the difference between 440 Hz and 432 Hz tuning?

A4 = 440 Hz is the international standard concert pitch adopted by ISO in 1955. A4 = 432 Hz (often known as Verdi’s A or Pythagorean tuning) tunes every note roughly 31.8 cents flatter. Our tuner allows you to select 440 Hz, 432 Hz, 442 Hz, or 444 Hz with real-time target frequency recalibration.

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