About the Guitar Tuning Reference Tones
This page plays a clean reference tone for each open string so you can tune by ear, and lists the exact frequency of every string in hertz. It covers standard guitar tuning, popular alternate tunings (drop D, half-step and full-step down, drop C, DADGAD, open G, open D, open E), 7-string guitar, 4- and 5-string bass, soprano/concert/tenor and baritone ukulele, mandolin, violin and 5-string banjo.
It is handy when you have no clip-on tuner, when you want to check an alternate tuning before a song, or when you are learning to hear whether a string is sharp or flat. Play a tone, pluck the string, and turn the peg until the "beating" (a slow wobble in volume) disappears.
Frequencies are calculated in 12-tone equal temperament from a reference pitch of A4 = 440 Hz. If your band or recording uses a different reference (for example A = 432 Hz or 442 Hz), change it and every string updates.
How to use the guitar tuning reference tones
- 1Choose your instrument and tuning.
- 2Leave the reference at 440 Hz unless your band tunes elsewhere.
- 3Press a string button to hear its pitch, then pluck the matching open string.
- 4Turn the tuning peg until the two sounds match and the wobble (beating) stops.
- 5Repeat for every string, then go round once more — retuning one string shifts neck tension slightly.
Formula and method
Each string's note is converted to a MIDI note number m (A4 = 69, middle C = C4 = 60) and its frequency is found with the equal-temperament formula: every semitone multiplies the frequency by 2^(1/12) ≈ 1.05946, and every octave doubles it. With A4 = 440 Hz, the low E of a guitar (E2, MIDI 40) is 440 × 2^(−29/12) = 82.41 Hz.
Note names use scientific pitch notation, where the octave number increases at each C. Guitar music is written an octave higher than it sounds, so the guitar's written "E3" low string actually sounds as E2.
- f
- Frequency of the string in hertz
- A4
- Reference pitch, normally 440 Hz
- m
- MIDI note number of the string (A4 = 69)
Worked examples
Standard guitar tuning
Standard tuning runs E2–A2–D3–G3–B3–E4. The low E vibrates at 82.41 Hz and the high E two octaves higher at 329.63 Hz (four times the frequency), a 24-semitone span.
Drop D guitar
Only the 6th string changes: it drops a whole step from E2 to D2, which is 440 × 2^(−31/12) = 73.42 Hz.
4-string bass at A = 432 Hz
A bass is tuned an octave below the guitar's four lowest strings. With A4 = 432 Hz the low E1 drops to 432 × 2^(−41/12) ≈ 40.45 Hz and G2 to about 96.22 Hz.
Frequently asked questions
What are the frequencies of standard guitar tuning?+
With A4 = 440 Hz: low E2 = 82.41 Hz, A2 = 110.00 Hz, D3 = 146.83 Hz, G3 = 196.00 Hz, B3 = 246.94 Hz and high E4 = 329.63 Hz.
How do I tune a guitar by ear?+
Play the reference tone, pluck the same open string and listen for beating — a slow pulsing in volume. Turn the peg in the direction that makes the pulsing slower until it disappears. Tune up to pitch rather than down so the string holds.
What notes is a ukulele tuned to?+
Soprano, concert and tenor ukuleles use G4 C4 E4 A4 ("My Dog Has Fleas"), with the G tuned above the C (re-entrant). Low-G ukuleles drop that string to G3; baritone ukuleles use D3 G3 B3 E4 like a guitar's top four strings.
What is drop D tuning?+
Drop D lowers only the 6th string a whole step from E to D (73.42 Hz). It gives a deeper bass note and lets you play power chords with one finger across the bottom three strings.
Should I tune to 440 Hz or 432 Hz?+
A4 = 440 Hz is the international standard concert pitch and what nearly all tuners and recordings use. Some orchestras tune slightly higher (442–443 Hz). 432 Hz is a personal preference; if you use it, everyone you play with must too.