D4 at every common reference pitch
A note’s frequency depends on what A4 is tuned to. The standard is 440 Hz; the other three are the ones you are most likely to meet. The cents column is how far each one sits from the 440 version — the same for every note, because changing the reference moves the whole scale together.
| Reference | D4 | vs 440 |
|---|---|---|
| A4 = 415 Hz · Baroque pitch | 276.98 Hz | −101.3¢ |
| A4 = 432 Hz · “Verdi” pitch | 288.33 Hz | −31.8¢ |
| A4 = 440 Hz · Standard (ISO 16) | 293.66 Hz | — |
| A4 = 442 Hz · Orchestral | 295.00 Hz | +7.9¢ |
One cycle of D4 lasts 3.405 ms, and its wavelength in air at 20 °C is 1.17 m. Hold it as a steady tone in the tone generator.
D4 on the piano
D4 is key 42 of 88, counting from the bottom — a white key. Press any key below to compare it with its neighbours.
D4 on the guitar
In standard tuning D4 is played in 4 places: 5th (A) string, fret 17, 4th (D) string, fret 12, 3rd (G) string, fret 7 and 2nd (B) string, fret 3. The same pitch in each place, with a different tone: lower strings sound warmer. Guitar music is written an octave higher than it sounds, so on a guitar part this note is printed as D5.
D4 on the staff
Instruments that can play D4
46 instruments play D4 within the normal range, and 2 reach it only at the extreme of theirs. Each links to its range chart; for a transposing instrument, the note on its part is shown.
Guitars and basses
Plucked and struck strings
Woodwind
Brass
Tuned percussion
Only at the extreme of their range
Voices: D4 is inside the typical range of the bass, baritone, tenor, alto, mezzo-soprano and soprano. Test your own range.
The harmonics of D4
A played D4 is not one frequency. A string or a pipe also sounds whole-number multiples of it, and the mix of those harmonics is the instrument’s tone. Here is where the first eight land — and why the 7th sounds out of tune against a piano.
| Harmonic | Frequency | Nearest note | Off by |
|---|---|---|---|
| 1 (fundamental) | 293.66 Hz | D4 | 0¢ |
| 2 | 587.33 Hz | D5 | 0¢ |
| 3 | 880.99 Hz | A5 | +2.0¢ |
| 4 | 1174.7 Hz | D6 | 0¢ |
| 5 | 1468.3 Hz | F♯6 | −13.7¢ |
| 6 | 1762.0 Hz | A6 | +2.0¢ |
| 7 | 2055.7 Hz | C7 | −31.2¢ |
| 8 | 2349.3 Hz | D7 | 0¢ |
Frequently asked questions
What is the frequency of D4?
D4 is 293.66 Hz in equal temperament with A4 tuned to 440 Hz, the international standard. At A4 = 432 Hz it is 288.33 Hz, and at the orchestral A4 = 442 Hz it is 295.00 Hz.
Which octave is D4 in?
The number is the octave in scientific pitch notation, where each octave starts on C and C4 is middle C. D4 is in octave 4, 2 semitones above middle C. In Helmholtz notation, used in older books, it is written d′.
How do I play D4 on a piano?
D4 is key 42 of 88, counting from the bottom — a white key.
Which instruments can play D4?
46 of the instruments we chart play D4 within their normal range, including violin, viola, cello, erhu, guitar, and 2 more reach it only at the extreme of their range.
Typing it? D4 is also written D4. Convert any frequency on the Hz-to-note converter.