Grab your guitar and click the mic button below — this tuner listens and tells you exactly how sharp or flat each string is, in real time.

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Online Guitar Tuner — Tune by Microphone, Free

Play any string into your microphone and watch the needle: this tuner hears the exact pitch, names the note, and tells you whether to tune up or down. No app install, no signup, audio never leaves your device.

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Press Start Tuning and play a string

Tap a string below to hear its perfect reference tone, then match it. Standard tuning: E2 A2 D3 G3 B3 E4. Best results in a quiet room, playing one string at a time.

100% private

Your microphone audio is analyzed locally in your browser. Nothing is recorded or uploaded.

No signup, no app

Works instantly in your browser — phone, tablet or desktop. Nothing to install.

Free forever

A full chromatic tuner with reference tones, free with no limits.

How to tune your guitar

  1. 1Allow the microphone

    Press Start Tuning and allow microphone access when your browser asks. A green dot means it is listening.

  2. 2Play one string

    Pluck a single open string clearly. The tuner shows the closest note and how many cents sharp or flat you are.

  3. 3Turn the peg

    Follow the needle to the center. When it turns green and says in tune, move to the next string.

Why use this guitar tuner

Live needle meter

A smooth, real-time needle shows exactly how sharp or flat you are — down to a few cents.

Fully chromatic

It detects any note, not just the six guitar strings — handy for alternate tunings too.

Reference tones

Tap any string button to hear its perfect pitch, then tune by ear like the pros.

Nearest-string hint

The closest guitar string lights up automatically as you play, so you always know which peg to turn.

Noise-friendly detection

Autocorrelation pitch tracking stays stable even in a normal room — just play clearly.

Private by design

All pitch analysis happens on your device. Your playing is never sent anywhere.

Frequently asked questions

How accurate is this tuner?
Within a few cents under normal conditions — plenty accurate for practice, rehearsal and live gigs. Play one string at a time in a reasonably quiet room for the best reading.
Why does the needle jump around?
Usually background noise, another ringing string, or a very soft pluck. Mute the other strings with your hand, pluck firmly, and let the note ring for a second.
What does “cents” mean?
There are 100 cents in each semitone (half step). If you are +12 cents, you are slightly sharp and should tune down a touch. At 0 cents you are perfectly in tune.
Can I use it for alternate tunings?
Yes — it is fully chromatic, so it names whatever note you play. The six string buttons are for standard tuning reference, but the meter works with any tuning.
Does it work on my phone?
Yes, on iPhone and Android browsers. Hold the phone near the guitar’s sound hole and grant microphone permission when asked.
Is my audio recorded or uploaded?
No. The microphone feed is analyzed in real time inside your browser and discarded. Nothing is saved, uploaded or shared.
Why is there no sound from my guitar in the tuner?
The tuner listens but does not play your guitar back through the speakers — that avoids feedback. Tap a string button below the meter to hear a reference tone.

Related tools

Online Mic Test

Check that your microphone is working before you tune.

 Online Tone Generator

Play any exact frequency for tuning and audio tests.

 Audio Speed Changer

Slow down songs to learn tricky guitar parts by ear.

 Audio Volume Booster

Make quiet practice recordings louder, free.

 Online Metronome

Keep perfect time while you practice, any tempo.
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