The tone keeps playing until you press Stop. Start with your volume low.
What is 440 Hz?
440 Hz — 440 vibrations per second — is the pitch of the A above middle C, written A4. It is the international reference pitch (standardised as ISO 16), so orchestras, pianos, electronic instruments and tuners all agree on it. Every other note is set relative to it; that is why it is also called concert pitch.
How the guitar strings relate to 440 Hz
- The open 5th string is A2, two octaves below: 110 Hz.
- The 1st string at the 5th fret is A4: exactly 440 Hz.
- The open 1st string, E4, is 329.63 Hz, and the low E is 82.41 Hz.
The frequency chart lists every string in every tuning.
Tuning to 440 Hz by ear
- Play the 440 Hz tone.
- Press the 1st (thinnest) string at the 5th fret and pluck it.
- Tune the string until the two sounds merge. While they differ you will hear a slow wobble, called beating; it slows down as you get closer and disappears when they match.
- Tune the other strings to the 1st with the 5th-fret method, or play each string’s note on the string notes page.
432 Hz vs 440 Hz
Some musicians tune A4 to 432 Hz instead, which is about 32 cents — a third of a semitone — lower. Claims that 432 Hz is more natural or healing have no scientific support, but it is a valid choice if you like the sound or want to match a recording made at that pitch. To tune to 432 Hz with this tuner, tune every string until it reads about −32 cents.
Does this tuner use 440 Hz?
Yes. All of FretPitch’s notes and frequencies are calculated from A4 = 440 Hz, the standard for guitars and almost all modern music.