Free Online Guitar Tuner

Tune by microphone in your browser, using a chromatic pitch detector. No app, no signup. Works for guitar, bass, ukulele, and more.

Standby

Auto-select string

Switches to string automatically

E2

Target 82.41 Hz

FLAT
SHARP

Action Required

Start tuner and pluck highlighted note.

Peg Rotation & Offset

Standby

Headstock Alignment

Tap a peg to tune that string specifically.

Instrument

Tuning Preset

Reference Pitch

A4 = 440 Hz

Concert pitch for A4. 440 is the standard; many orchestras use 442.

Quick Tuning Guidelines

  • 1.Tap the Start Recording button at the top to initialize your microphone.
  • 2.Pluck one string cleanly at a time. Let it vibrate naturally to get a continuous frequency reading.
  • 3.Adjust your tuning pegs until the dial centers in the green zone (around 0 cents).
  • 4.Watch indicators: amber is the currently selected note, green is the automatically detected audio feed.
About GuitarTunePro

The Free Online Chromatic Guitar Tuner

Autocorrelation-based pitch detection in your browser, with measured accuracy data to back it up. No download, no subscription, no compromise.

GuitarTunePro is a free online chromatic guitar tuner built for players of all skill levels — from first-time beginners to touring professionals. It runs entirely in your web browser using the Web Audio API, which means you can tune your guitar with a microphone on any device without installing anything.

Unlike many tuners that rely on simple frequency estimation, GuitarTunePro uses a YIN-inspired autocorrelation algorithm operating at a 48 kHz sample rate with a 4096-sample processing window — not an FFT. We've tested and published the actual measured accuracy rather than quoting a bare precision figure with nothing behind it.

The tuner supports 6-string, 7-string, 12-string, bass, ukulele, mandolin, banjo, violin, viola, and cello, with presets for Standard (E A D G B E), Drop D, Half-Step Down, Open G, Open D, DADGAD, and more. Automatic string detection identifies which string you're playing so you can tune all strings without touching the screen.

GuitarTunePro is built and maintained by Manusha Dananjaya. All audio processing happens locally on your device — no audio data is ever sent to a server. The tuner is completely free and always will be.

No Download RequiredWorks on MobileAccuracy Data PublishedAuto String Detection10+ Tuning PresetsBass & Ukulele Support100% Free
Alternate Tuning Tools

Dedicated Alternate Tuners

Each page below is a full working tuner, pre-loaded with the correct target notes so you can switch tunings in seconds.

D · A · D · G · B · E

Drop D Tuner

Lower your 6th string to D for one-finger power chords — the rock and metal staple.

Open Drop D Tuner →
C · G · C · F · A · D

Drop C Tuner

Drop D's heavier cousin, two semitones lower. The metalcore and hardcore standard.

Open Drop C Tuner →
C♯ · G♯ · C♯ · F♯ · A♯ · D♯

Drop C♯ Tuner

Drop D a half step down — the drop tuning for bands that play in E♭. Also called Drop D♭.

Open Drop C♯ Tuner →
B · F♯ · B · E · G♯ · C♯

Drop B Tuner

The low-tuned metal standard on six strings: Drop D's shape, three semitones lower.

Open Drop B Tuner →
A · E · A · D · G · B · E

Drop A Tuner

The 7-string drop tuning: low B down to A for one-finger power chords at the bottom of the range.

Open Drop A Tuner →
D · A · D · G · A · D

DADGAD Tuner

The Celtic tuning — an open Dsus4 that suits modal folk and fingerstyle.

Open DADGAD Tuner →
D · G · D · G · B · D

Open G Tuner

Keith Richards' signature tuning for blues, folk, and slide guitar.

Open Open G Tuner →
D · A · D · F♯ · A · D

Open D Tuner

Deep and resonant — the Delta blues slide tuning, also called Vestapol.

Open Open D Tuner →
E · B · E · G♯ · B · E

Open E Tuner

Bright electric slide tuning used by Duane Allman and Derek Trucks.

Open Open E Tuner →
C · G · C · G · C · E

Open C Tuner

The deepest open tuning — huge, piano-like resonance for solo fingerstyle.

Open Open C Tuner →
E · A · E · A · C♯ · E

Open A Tuner

Tight, bright slide tuning built around the classic blues key of A.

Open Open A Tuner →
E♭ · A♭ · D♭ · G♭ · B♭ · E♭

Half Step Down Tuner

Every string down a semitone — Hendrix, SRV, and Guns N' Roses. Shapes unchanged.

Open Half Step Down Tuner →
D · G · C · F · A · D

Full Step Down Tuner

D standard — all six strings down a whole step for weight without new shapes.

Open Full Step Down Tuner →
C · F · B♭ · E♭ · G · C

C Standard Tuner

Every string down two whole steps. Standard shapes, a low C, and a much heavier sound.

Open C Standard Tuner →
B · E · A · D · F♯ · B

B Standard Tuner

Standard tuning a fourth lower — the usual tuning of a baritone guitar, with every chord shape unchanged.

Open B Standard Tuner →
E3 · A3 · D4 · G4 · B3 · E4

Nashville Tuner

High-strung tuning: the 12-string's octave strings on a six-string, for a bright, shimmering layer.

Open Nashville Tuner →
A · = · 432 · Hz

432 Hz Tuner

Standard tuning about a third of a semitone lower, with A at 432 Hz instead of 440.

Open 432 Hz Tuner →
D · A · D · G

Drop D Bass Tuner

Bass E string down to D1 — the bass half of every Drop D riff, and a lower note on a 4-string.

Open Drop D Bass Tuner →
G3 · C4 · E4 · A4

Low G Ukulele Tuner

Linear GCEA with the G an octave down — a fuller, deeper ukulele with a real bass note.

Open Low G Ukulele Tuner →
Practice & Setup

More Than a Tuner

A daily practice plan with a streak to keep, scales on the whole neck, strumming you can play along with, and a transposer for any song — all free, all in your browser.

Guitar Chord Library

Diagrams and audio for major, minor, 7th, sus, diminished and augmented chords in every key — every shape checked against chord theory before it ships.

Browse the Chord Library →

Free Online Metronome

Tuning is half of it. Set a tempo from 30 to 300 BPM, tap the beat you want, and practise against sample-accurate timing — with time signatures, subdivisions, and an accented downbeat.

Open the Metronome →

Vocal Pitch Detector

Sing or hum and see the note, the frequency, and how many cents sharp or flat you are — in real time. Includes a scrolling pitch graph, a vocal range finder, and a note-matching trainer.

Open the Vocal Pitch Detector →
Other Instruments

Not a 6-String?

The same pitch detection engine, pre-configured for bass, ukulele, mandolin, banjo, extended-range guitars, and the orchestral strings.

E · A · D · G

Bass Tuner

Standard 4-string bass tuning, an octave below the guitar's bottom four strings.

Open Bass Tuner →
B · E · A · D · G

5-String Bass Tuner

Adds a low B below standard bass tuning, down to 30.87 Hz.

Open 5-String Bass Tuner →
G · C · E · A

Ukulele Tuner

Standard reentrant GCEA tuning for soprano, concert, and tenor ukulele.

Open Ukulele Tuner →
B · E · A · D · G · B · E

7-String Guitar Tuner

Standard tuning plus a low B string — the extended-range metal standard.

Open 7-String Guitar Tuner →
EE · AA · DD · GG · BB · EE

12-String Guitar Tuner

Six courses of paired strings, four of them tuned in octaves. Chiming and full.

Open 12-String Guitar Tuner →
D · G · B · E

Baritone Ukulele Tuner

Linear DGBE tuning — the same as a guitar's top four strings, not GCEA.

Open Baritone Ukulele Tuner →
GG · DD · AA · EE

Mandolin Tuner

Four unison pairs tuned in fifths, the same notes as a violin.

Open Mandolin Tuner →
g · D · G · B · D

Banjo Tuner

5-string banjo in open G, with the short high 5th string that drones over everything.

Open Banjo Tuner →
G · D · A · E

Violin Tuner

Tune in fifths from the A, with pegs for big moves and fine tuners for the last few cents.

Open Violin Tuner →
C · G · D · A

Viola Tuner

A fifth below the violin. Shares the violin's top three strings and adds a low C.

Open Viola Tuner →
C · G · D · A

Cello Tuner

The viola's strings an octave lower, down to C2 at 65.41 Hz.

Open Cello Tuner →
E · A · D · G

Double Bass Tuner

Upright bass in orchestral tuning, in fourths down to E1 — tune with harmonics for the cleanest read.

Open Double Bass Tuner →
D · G · B · D

Cavaquinho Tuner

The four-string voice of samba, pagode and choro, in the standard Brazilian D G B D.

Open Cavaquinho Tuner →

Complete Online Guitar Tuner Guide

How to Tune Your Guitar by Ear or with a Mic

Tuning your guitar is the most important skill you can learn as a beginner. An out-of-tune guitar will make even the greatest players sound bad. Our online guitar tuner simplifies this process. Simply allow microphone access, pluck a string, and our advanced pitch detection algorithm will tell you exactly which note you are playing and whether it is too sharp (high) or flat (low).

The standard tuning for a 6-string guitar, starting from the thickest string (lowest pitch) to the thinnest string (highest pitch), is E - A - D - G - B - E. A helpful mnemonic device to remember these notes is: "Eddie Ate Dynamite, Good Bye Eddie".

Exploring Alternative Tunings

While standard tuning is extremely versatile, exploring alternative tunings can unlock entirely new sonic possibilities and make certain chords easier to play. Our tuner supports dozens of alternative tunings instantly.

  • Drop D (D A D G B E): Popular in rock and metal for easy, heavy power chords. Lower the thick E string down a whole step to D.
  • Open G (D G D G B D): A favorite of blues players and the Rolling Stones. Strumming all strings open produces a G major chord.
  • Half-Step Down (Eb Ab Db Gb Bb Eb): Lowers the tension on the strings, making bending easier, and creates a darker, heavier tone.

Frequently Asked Questions

Is the online guitar tuner accurate?

Yes, GuitarTunePro uses the Web Audio API and highly precise algorithmic pitch detection. It is accurate to within ±1 cent, making it suitable for professional stage setup, recording sessions, and daily practice.

Why isn't the tuner hearing my guitar?

Ensure that you have granted microphone permissions in your browser. If you are using an electric guitar without an amplifier, the acoustic sound may be too quiet. Try moving your instrument closer to the device's microphone or plugging into a USB interface.

FAQ

Frequently Asked Questions

Everything you need to know about using GuitarTunePro.

Does this work without downloading anything?

Yes. GuitarTunePro is a completely browser-based free online guitar tuner — no app download, no installation, and no account required. Open the site on any device with a modern web browser and a microphone, and you're ready to tune.

How accurate is the tuner?

GuitarTunePro uses an autocorrelation, YIN-inspired pitch detection algorithm analyzing 4096 audio samples at a 48 kHz sample rate. In our own synthesized-signal testing, single-reading error stayed under 5 cents per string in quiet conditions and under about 8 cents worst-case with background noise present — see the full methodology and test data at /accuracy.

Does this work on mobile?

Yes. The tuner works on iPhone, Android, tablets, laptops, and desktops. Simply allow microphone access when prompted by your browser, and the tuner will detect your guitar's pitch in real time — no cables or adapters needed.

What guitar tunings are supported?

GuitarTunePro supports Standard (E A D G B E), Drop D, Half-Step Down (Eb), Full-Step Down (D), Open G, Open D, Open A, DADGAD, and many more. You can also use it as a chromatic tuner to detect any note freely.

What instruments can I tune?

The tuner supports 6-string guitar, 7-string guitar, 12-string guitar, bass guitar (4-string and 5-string), ukulele, baritone ukulele, mandolin, 5-string banjo, violin, viola, and cello. Switch between instruments from the selector below the tuner, or open the dedicated page for your instrument.

Is the tuner completely free?

Yes, GuitarTunePro is 100% free with no hidden fees, subscriptions, or paywalls. The core tuner experience is advertisement-free and will remain free for all players.

New to guitar tuning? Explore our free guides: