Guitar Tuner
Tune a guitar, bass or ukulele through your microphone with a live needle.
Tune By Ear, With A Needle To Check You
A tuner listens to a plucked string, works out its pitch and tells you how far it is from the note it should be. This one does that through your computer or phone microphone, with the needle measured in cents — hundredths of a semitone — so you can see a string that is only slightly flat, not just one that is badly out.
It knows the common tunings for guitar, bass and ukulele, picks the string you are nearest to automatically, and plays a reference tone for any string you tap. A chromatic mode names whatever note it hears, for any instrument. The microphone audio is analysed on your device and never recorded or sent anywhere.
Key features
- Guitar, bass and ukulele — standard, drop D, half-step down, D standard, open G and DADGAD.
- Cents needle — within five cents either side lights up as in tune.
- Octave-safe detection — does not mistake a low E for the E below it.
- Reference tones — tap any string to hear the note it should be.
- Adjustable A4 — tune to 440 Hz, or match an orchestra or recording at another pitch.
This tool runs entirely inside your browser using native Web APIs. Your files and text are never uploaded to a server, never logged and never shared with third parties.
How to use: Guitar Tuner
- Choose your tuning
Standard guitar is selected; pick bass, ukulele or an alternate tuning if you need one. - Start the microphone
Allow microphone access when your browser asks. - Pluck one string and let it ring
The display names the nearest string and shows how sharp or flat it is. - Turn the peg until it reads in tune
Tune up to the note rather than down to it, so the string holds.
Technical specifications
| Processing location | Entirely in your browser — no server round trip |
|---|---|
| Data uploaded | None. Files and text never leave your device |
| Price | Free — no account, no trial, no usage cap |
| Category | Audio |
| Works offline | Yes, once the page has loaded |
| Browser support | Chrome 90+, Edge 90+, Firefox 90+, Safari 15+ |
| Interface languages | English, 中文, हिन्दी, Español, العربية |
Frequently asked questions
Why does the tuner jump around?
The first moment of a pluck is noisy, and background sound confuses any tuner. Pluck firmly, let the note ring, keep the instrument close to the microphone, and turn off noise suppression in your system settings if the low strings struggle.
What are the notes of standard tuning?
From the thickest string to the thinnest: E A D G B E — E2, A2, D3, G3, B3 and E4. A common way to remember it is Eddie Ate Dynamite, Good Bye Eddie.
How accurate does tuning need to be?
Within about five cents most listeners hear no problem, and that is the in-tune window here. Chords can still sound slightly off on a guitar whose intonation needs setting up — that is a job for the bridge saddles, not the tuner.
Does it work on a phone?
Yes, in any modern mobile browser. Allow microphone access and hold the phone near the sound hole or amplifier.
Is my microphone recorded?
No. The audio is analysed a few times a second on your own device to find the pitch, and nothing is saved or transmitted. The microphone stops when you press Stop or leave the page.