Online Guitar Tuner

Grant microphone permission only when you are ready, play one clean note at a time, and use cents plus target-frequency feedback to tune locally in the browser.

Tuning

Reference A4

Input

—

Waiting for microphone

−50¢ flatin tune+50¢ sharp

—Cents

—Target

—Nearest string

—Signal

Pitch detection runs locally in your browser. A quiet room and a clean single note improve stability. Microphone permission is required.

String targets & cents windows

Verify every target frequency from the selected tuning/reference A4 and see exact ±5/±10-cent frequency windows.

Tuning evidence

String	Target Hz	±5¢ range	±10¢ range

Practice and playback notes

connects timing, tuning, pitch reference, virtual instruments and music-theory tools without requiring an account. Existing interactive engines remain intact while the new workflow makes it easier to move from a practical task—keep time, tune, play, identify, transpose—to the next relevant tool.

Audio and theory boundaries

Microphone pitch detection depends on the device, room and signal quality. Equal-tempered frequency math does not measure a real instrument, and chord/scale naming can have multiple enharmonic or theoretical interpretations. Reference tones and noise should be used at comfortable playback levels; browser controls do not measure sound-pressure exposure.

Practical guide and verification

Use the interactive product above first. These notes add interpretation, verification and limits below the results and product controls.

Tune from a stable sustained note

Pluck one string at a time and let the initial attack settle before judging cents. The first transient can contain strong harmonics and pitch movement that make a correct string look briefly sharp or unstable.

Use the correct target tuning before adjusting a string

Standard, Drop D and alternate tunings assign different target frequencies to the same physical string. Confirm the selected tuning and string target before turning a tuning machine.

Cents show relative pitch error

Zero cents means the detected pitch matches the selected equal-tempered target at the chosen A4 reference. A positive value is sharp and a negative value is flat; the same number of hertz does not represent the same cent error at every note.

Microphone conditions affect detection

Room noise, another sounding string, clipping and a distant microphone can cause note jumping or octave errors. Move closer, mute unused strings and reduce competing sound before assuming the instrument itself is unstable.

Reference pitch changes every target frequency

A4 = 440 Hz is common but not universal. If an ensemble uses 442, 432 or another reference, set that value before tuning so every derived string target is consistent with the group.