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. Now with a built-in metronome and string-life tracking, it's a whole practice kit. 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 • The full metronome — 40–240 BPM, meters from 2/4 to 7/8, and tap tempo • String-life tracking for one instrument • 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. PRACTICE, NOT JUST TUNING A metronome built into the same instrument, sharing the same LED display: 40–240 BPM, time signatures from 2/4 to 7/8, tap tempo, and an accented downbeat. Free for everyone. And a string tracker that answers the question every player guesses at: are these due for a change? ChromTuner watches both how long a set has been on and how much you've actually played it — counting the sessions you tune — so the guitar that lives in its case and the one that gigs every weekend aren't treated the same. Add your instruments, pick one up, and the tuner switches to its tuning automatically. CHROMTUNER PRO — ONE PURCHASE, YOURS FOREVER A single in-app purchase unlocks everything. No subscription, no account: • All 17 tunings: DADGAD, Open G, Open D, 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 • Track string life across every instrument you own, not just one • 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 ON YOUR WRIST ChromTuner includes a full app for Apple Watch: the same detection engine and a live string indicator that lights up as you move across the neck, so both hands stay on the instrument. Swipe to the metronome and it clicks in time while tapping the beat on your wrist — turn the Digital Crown to set the tempo. The free tier works on your wrist too. 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.