Tuning Fork Generator

A440 means the note A above middle C vibrates at exactly 440 Hz. It was adopted as the international tuning standard (ISO 16) in 1955. Orchestras, choirs, and instrument manufacturers worldwide tune to this reference so that all instruments sound in tune with each other. Some European orchestras use A442 or A443 for a slightly brighter sound.

A real tuning fork produces a nearly pure sine wave — a single frequency with no harmonics. This tool replicates that behavior exactly. A pure sine wave is ideal for tuning because it gives you a clean, unambiguous pitch reference without overtones that could confuse your ear or a tuner. If you need other waveforms, try our Tone Generator.

Yes! Select the reference pitch you need (e.g., A440 for most instruments, or use the note selector for specific strings), play the tone, and tune your instrument to match. For guitar, common references are E2 (82.41 Hz), A2 (110 Hz), D3 (146.83 Hz), G3 (196 Hz), B3 (246.94 Hz), and E4 (329.63 Hz). For a more interactive experience, try our Chromatic Tuner which listens to your instrument via microphone.

A440 (440 Hz) is the international standard. A442 (442 Hz) is used by many European orchestras, particularly in Germany, Austria, and some ensembles in France. The 2 Hz difference produces a slightly brighter, more brilliant sound. Both presets are included so you can match whichever standard your ensemble uses.

No. All audio generation happens 100% locally in your browser using the Web Audio API. No sound is recorded, no data is sent to any server. The tool works completely offline once loaded.

Physical tuning forks are precision-machined to vibrate at a specific frequency — typically A440 Hz, A442 Hz, or a note used in medical audiometry (e.g., 512 Hz for hearing tests). They maintain accuracy within ±0.5 Hz under normal temperature conditions but drift when cold or hot (metal expands and softens, lowering the pitch). This online generator uses the Web Audio API's OscillatorNode, which is locked to the device's audio clock and accurate to well under 1 Hz at any temperature — more consistent than a real fork. However, your speaker or headphone's frequency response may colour the output slightly, whereas a struck fork vibrates in open air without transducer colouration.

A choir director typically sounds the tonic or the dominant of the upcoming key before a piece begins, allowing singers to internally place the pitch before the first note. Common pitches used are: Bb3 (233 Hz) for Bb-major works, C4 (261.63 Hz) for C-major or C-minor, and A440 as a universal starting point. The presets on this page cover all of those. For a cappella groups, individual voice parts often receive their starting note separately — use the note selector to sound the soprano, alto, tenor, and bass entry pitches in sequence. If you want to verify a singer is hitting the pitch accurately after tuning up, the microphone-based frequency detector can confirm the sung pitch in real time.

Yes. Type any frequency directly into the Custom Frequency field. For 432 Hz tuning (sometimes called "Verdi tuning" or "scientific pitch"), type 432 and click Play. For A444 (used by some orchestras in Eastern Europe), type 444. The note display will show the nearest equal-temperament note name and the cents deviation from that note — at 432 Hz it will show A4 at roughly −32 cents flat relative to A440. Note that 432 Hz is not an internationally recognised standard and the scientific claim that it sounds objectively "better" is not supported by controlled studies; it is simply a different pitch centre that some ensembles prefer.

This tool generates a mathematically pure sine wave, but every playback device has its own frequency response curve. Most laptop speakers roll off steeply below about 150–200 Hz, so bass notes (C2 and below) will sound quiet or distorted through built-in speakers even though the signal is correct. Headphones typically reproduce 80 Hz and above accurately. For low-register tuning references (double bass open strings, organ pedal notes), use headphones or an external speaker. For pitches above 200 Hz the difference between playback devices is minimal and the sine wave reference is reliable.