What is Guitar/Instrument Tuner?

A chromatic instrument tuner that uses your device's microphone to detect pitch in real time. Works with guitar, bass, ukulele, violin, and any other instrument. Shows the detected note, how many cents sharp or flat you are, and a visual tuning meter.

Under the hood, a YIN-inspired autocorrelation algorithm reads the microphone stream through the Web Audio API and reports pitch with cent-level accuracy. The reference for A4 is adjustable from 415 to 466 Hz, so historical and orchestra tunings are covered. Detection works on string, wind, and brass instruments — anything that produces a stable fundamental tone above background noise.

How to use

1. Step 1 — Allow microphone access when prompted, then play a single note on your instrument close to the microphone.
2. Step 2 — Watch the tuning display: it shows the detected note name, octave, frequency in Hz, and a needle showing cents deviation from perfect pitch.
3. Step 3 — Adjust your tuning peg until the needle centers and the display turns green, indicating the note is in tune (within ±5 cents).

When to use

• Tuning a guitar before band practice without buying a physical clip-on tuner.
• Checking that a violin is at A=442 Hz for an orchestra rehearsal in Europe.
• Teaching a beginner how cents work by showing the meter swing as they tighten the string.

Result

Tune a guitar to standard tuning (E2 A2 D3 G3 B3 E4): pluck the low E string — the display shows 'E2' at 82.4 Hz. Adjust until the needle is centered.

FAQ

How accurate is microphone-based tuning compared to a clip-on tuner?

Detection lands inside ±2 cents on a quiet desk and a steady plucked note. Clip-on tuners pick up string vibration directly and stay accurate in noisy rooms — for stage use, a clip-on still wins. For practice at home, the mic is plenty.

Why does the detected note keep jumping between two values?

That usually means you're between notes (around 50 cents off) and the algorithm is flipping between the lower and upper neighbour. Tighten or loosen the string until the meter settles cleanly on one side.

Can I tune to alternative tunings like Drop D or Open G?

Yes — pick a preset from the Tuning row above the meter and the reference cards switch to the right notes. Standard, Drop D, Half-Step Down, Open G, Open D, Open E, Open A, C Standard, and DADGAD are all one tap, and there are dedicated banjo and mandolin instruments too. The detector itself is chromatic, so anything you play is still identified by name.

Does this work for bass guitar and low instruments?

Yes. Pick the Bass instrument tab and the reference flips to E1 A1 D2 G2. Detection holds down to about 30 Hz, which covers a five-string bass low B near 31 Hz. Below that, most laptop and phone mics roll off and the reading gets jumpy.

Why doesn't the tuner pick up when I play a chord?

The algorithm needs a single fundamental frequency to lock onto. Chords contain several notes at once, so the autocorrelation can't find a clean answer. Pluck one string at a time.

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