Free online guitar tuner, right in your browser

Guitar Tuner Ultra is a free online guitar tuner that runs entirely in your web browser. There is nothing to download and no app to install — just open the page, allow your microphone, and start tuning in seconds. Whether you play an acoustic guitar, an electric guitar, a ukulele or a mandolin, this online guitar tuner listens to each string through your device's mic and shows you, in real time, exactly how sharp or flat you are. The result is a fast, accurate and genuinely free guitar tuner that helps you bring every string to perfect pitch without buying a clip-on tuner, a pedal or any extra hardware. It is the kind of quick, reliable guitar tuner online players reach for every day — at home, in the practice room or backstage before a show.

Tune with your microphone, right in the browser

Our online guitar tuner with microphone uses the Web Audio API to analyse the sound of your instrument as you play. Pluck a string and the tuner detects the pitch, names the note, and guides a needle toward the centre as you get closer to the target. Because all of the processing happens locally, your audio never leaves your device — the mic is only used to hear your guitar, and nothing is recorded, stored or uploaded. That makes Guitar Tuner Ultra a private, secure online guitar tuner with mic support that works on desktops, laptops, tablets and phones alike.

An acoustic and electric guitar tuner in one

This free online guitar tuner works equally well as an acoustic guitar tuner and an electric guitar tuner. Acoustic players can tune straight through a built-in or external microphone, while electric guitarists can tune through a mic or simply by playing unplugged. Standard tuning (E A D G B E) is loaded by default, so you can pick up any six-string and tune it accurately in moments — no cables, apps or physical tuners required.

Alternate tunings: Standard, Drop D, Open G and beyond

Beyond standard tuning, Guitar Tuner Ultra includes ready-made presets for popular alternate tunings. Switch to Drop D for heavier rock and metal riffs, or Open G for slide and blues. Because the tuner detects the exact note you play, you can also tune by ear to setups like half step down, Open D and Drop C — just match each string to its target note. We're building dedicated tools too, so a Drop D tuner, Open D guitar tuner, half-step-down tuner and bass guitar tuner are on the way.

Practice guitar chords with AI Chord Practice

Staying in tune is only half the journey — the other half is clean, fast chord changes. That's why Guitar Tuner Ultra includesAI Chord Practice, a free guitar chord practice trainer that uses the same microphone-powered listening as the tuner. Choose the chords you're learning — open chords, barre chords, power chords, or the classic progressions in the keys of G, C and D — and strum each target before the timer runs out. The AI-powered chord detection recognises what you actually played, so a muted string or the wrong chord doesn't score. It's the fastest way to turn chord shapes from the chord libraryinto smooth, automatic changes.

Fast, accurate and completely free

Accuracy matters when you tune. Guitar Tuner Ultra detects pitch to within a few cents — precise enough for practice, recording and live performance. The clean, responsive gauge keeps tuning simple for complete beginners while staying quick enough for working musicians. And it is 100% free: no sign-up, no subscription and no ads standing between you and being in tune. A browser-based tuner also means nothing to update and no storage to spare — you always get the latest version the moment the page loads, on any device you own.

How to use the online guitar tuner

1. Open the tuner and press Start.
2. Allow microphone access when your browser asks.
3. Play one string clearly and let it ring.
4. Watch the needle — tighten the string if you're flat, loosen it if you're sharp.
5. Repeat for each string until they all read in tune.

Ready to sound your best? Open the tuner, browse the guitar chord library, or read our step-by-step tuning guides for Drop D, Open G, standard tuning and more.