About UkuleleTuner.io
How the pitch meter, high-G and Low-G references, microphone privacy, instrument limits, and correction process work.
Purpose and Scope
UkuleleTuner.io is a ukulele-specific pitch tool and reference library. It covers standard re-entrant G4–C4–E4–A4, Low G, baritone DGBE, and several documented alternate tunings. The site combines a microphone tuner with string-order and frequency references, a complete tuning workflow, and troubleshooting for octave mistakes, stretching strings, slipping pegs, and fretted-note intonation.
What the Tuner Measures
After microphone permission is granted, the tuner estimates the strongest repeating frequency in the sound. It compares that estimate with the selected ukulele string and reports the difference in cents. Pitch estimation uses an autocorrelation-based detector in the browser. Samples are processed on the device; UkuleleTuner.io does not intentionally record or upload microphone audio.
Frequency Method and Octave Handling
A440 targets use 12-tone equal temperament: frequency equals 440 × 2(n − 69) / 12, where n is the MIDI note number. Standard high-G targets are G4 = 392.00 Hz, C4 = 261.63 Hz, E4 = 329.63 Hz, and A4 = 440.00 Hz. The frequency calculator applies the same formula to A4 references from 415 through 445 Hz.
The octave is a safety-critical part of the target. Low G3 is 196.00 Hz—exactly one octave below high G4—while baritone uses a different D3–G3–B3–E4 system. The guides identify physical string order and octave so a matching note letter is not mistaken for the right tension.
Limits and Instrument Safety
A microphone can measure a repeating sound, but it cannot identify the installed string material or gauge, inspect a bridge tie, friction peg, nut slot, saddle, neck joint, or fret, or confirm that a raised tuning is suitable for a particular ukulele. The guides therefore separate pitch-reading problems from mechanical ones and say when to stop before adding more tension or making an irreversible setup change.
Ownership, Review, and Corrections
John Sorrentino created and maintains UkuleleTuner.io as part of a collection of focused browser tools. Tuning targets, octave labels, calculations, preset descriptions, and educational pages are reviewed when the detector or reference library changes. The site is independent and is not a substitute for a teacher, repair professional, instrument maker, or string maker.
If a note, octave, frequency, tuning name, or instruction appears wrong, use the contact page and include the page, ukulele size, installed string set, high or Low G, selected tuning, device, browser, displayed result, and expected result. Reproducible corrections take priority over adding presets.