Chromtuner: Guitar Tuner

ChromTuner is a precision chromatic tuner with the soul of vintage hardware — a warm LED display, instant response, and pitch detection accurate to a fraction of a cent. It's built on the same audio engine as ChromTuner for macOS, trusted by guitarists, string players, and instrument techs. FREE MEANS FREE The free version is a complete tuner, not a demo: • Chromatic mode — tune any instrument, any note, from a 5-string bass's low B to the top of a violin's range • Guitar presets: Standard E and Drop D, with tap-to-play reference tones for every string • Two displays: the classic LED bar meter and a vintage analog needle • A gentle haptic tap the moment a string locks in tune • Full detection accuracy — the free version uses the exact same engine as Pro • No ads. No account. No tracking. Ever. ACCURACY YOU CAN TRUST Under the retro looks is a serious instrument: YIN pitch detection with octave-error correction (so a guitar's strong second harmonic can't fool it), median filtering to reject transients, and processing at the microphone's full sample rate. It hears a quietly plucked acoustic string and stays rock-steady while you tune. CHROMTUNER PRO — ONE PURCHASE, YOURS FOREVER A single in-app purchase unlocks everything. No subscription, no account: • All 17 tunings: DADGAD, Open G, half-step down, 7-string, 4- and 5-string bass, violin, viola, cello, double bass, ukulele, mandolin, and banjo • Peterson-style strobe display for sub-cent precision, plus a minimal wave view • 8 temperaments with a movable root: Just intonation, Pythagorean, ¼-comma meantone, Werckmeister III, Kirnberger III, Vallotti, and Young — for early music, keyboards, and curious ears • A4 calibration from 349 to 500 Hz — dial in 440, 442, Baroque 415, or detect the reference by listening to another instrument • Capo mode: clip on at any fret and strings still read by name • Transpose ±11 semitones for horn keys and alternate readings • Hz readout for techs and tinkerers • Full personalization: accent colors, fonts, meter styles, LED glow, corner roundness — design your own instrument and save your signatures MADE FOR THE STAGE AND THE COUCH A big note readout you can read from across the room, thumb-reach controls for one-handed use, true dark themes for dim stages, and a screen that stays awake while you tune. PRIVATE BY DESIGN The microphone signal is analyzed on your device in real time and is never recorded, stored, or sent anywhere. ChromTuner works completely offline and collects no data at all.