# Online Guitar Tuner > Tune your guitar by microphone with real-time, cent-precision pitch detection Free online guitar tuner. Tune by microphone with real-time pitch detection and cent-precision needle. 8 tunings plus Bass, Ukulele, Violin. 100% private. URL: https://tools.scoreroute.com/tools/guitar-tuner/ Markdown: https://tools.scoreroute.com/tools/guitar-tuner/.md ## Strings — click to play the reference tone for tuning by ear ### Real-Time Pitch Detection Autocorrelation frequency analysis on your live microphone for instant, stable readings #### Automatic String Recognition The tuner highlights which string you are playing and tracks tuning progress #### 8 Guitar Tunings + 4 Instruments Standard, Drop D, Drop C, Half-Step, Full-Step, Open G, Open D, DADGAD plus Bass, Ukulele, Violin, Viola #### Tuning by Ear Play any string's reference tone through your speakers when no microphone is available ## Why AI Cannot Tune Your Guitar An AI chatbot has no microphone, no audio input and no access to the waveform your guitar produces, so it can never hear whether your low E is 8 cents flat or your B string is 15 cents sharp. Tuning is a physical measurement: the fundamental frequency of a real string must be captured and compared against the equal-tempered scale, which requires living DSP running on the device that holds the microphone. This tool does exactly that with an autocorrelation pitch-detection algorithm in your browser. A chatbot can quote EADGBE all day, but only a real tuner can tell you the needle moved to center because your string actually reached the right frequency. ### How the Guitar Tuner Works Good online tuners using the Web Audio API and autocorrelation reach within a few cents of a dedicated clip-on or pedal tuner in a quiet room. For practical playing, +-5 cents is in tune. Accuracy depends mainly on your environment: a clearly plucked string close to the mic beats a noisy room every time. Yes. Any modern smartphone browser (Safari on iPhone, Chrome on Android) supports the Web Audio API and microphone access over HTTPS. Hold the phone near the soundhole of an acoustic or the pickups of an electric for the strongest signal. No. The tuner is completely free, has no account, no watermark and no daily limit. All signal processing happens in your browser, so there is no server cost to pass on to you. Switch to chromatic mode to tune any note of any instrument by ear or by microphone. The presets cover the standard 6-string sets; chromatic mode simply shows the nearest note and cents for whatever you pluck. A cent is 1/100 of a semitone. Twelve notes per octave are each 100 cents apart. Most players consider a string within +-5 cents of the target to be in tune; beyond about +-15 cents most people can hear the string is off. Jumpy readings come from background noise, two strings ringing together, heavy effects pedals, or reading too soon after a hard pluck. Mute other strings, play the note again after it settles and tune in a quiet room. The built-in 60 Hz hum filter on the electrical strings is a common cause: tune electric guitars on a clean signal. Yes. The tuner only works while this page is open and the Start Tuner button is running, because it needs the live microphone stream. Bookmark the page so it is one click away whenever you pick up the guitar. - **Pick your instrument and tuning.** Select Guitar, Bass, Ukulele, Violin, Viola or chromatic mode, then choose a tuning preset such as Standard EADGBE, Drop D or DADGAD. - **Start the tuner and allow the microphone.** Your browser will ask for permission; audio is analyzed locally and never leaves your device. - **Pluck one string and let it ring.** The big note display shows the detected note, the needle shows how sharp or flat you are in cents (1/100 of a semitone), and the matching string chip lights up. - **Turn the tuning peg until the needle reaches center.** When the string is in tune, the note turns green and the string chip goes green. - **Repeat for each string.** Re-check the first strings after tuning the rest, because changing tension on one string shifts the others slightly. ## Related Tools - [Metronome](/tools/metronome/) - Precision BPM, tap tempo and rhythm practice - [Speaker Test](/tools/speaker-test/) - Check channels, frequency sweep and stereo - [Microphone Test](/tools/microphone-test/) - Test mic input levels and quality - [Webcam & Mic Test](/tools/webcam-test/) - Check camera, microphone and speakers - [Voice Recorder](/tools/voice-recorder/) - Record and save audio as MP3 or WAV ## References - [MDN — Canvas API](https://developer.mozilla.org/en-US/docs/Web/API/Canvas_API) - [MDN — HTMLMediaElement](https://developer.mozilla.org/en-US/docs/Web/API/HTMLMediaElement)