C♯7 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 | C♯7 | vs 440 |
|---|---|---|
| A4 = 415 Hz · Baroque pitch | 2091.5 Hz | −101.3¢ |
| A4 = 432 Hz · “Verdi” pitch | 2177.1 Hz | −31.8¢ |
| A4 = 440 Hz · Standard (ISO 16) | 2217.5 Hz | — |
| A4 = 442 Hz · Orchestral | 2227.5 Hz | +7.9¢ |
One cycle of C♯7 lasts 451.0 µs, and its wavelength in air at 20 °C is 15.5 cm. Hold it as a steady tone in the tone generator.
C♯7 on the piano
C♯7 is key 77 of 88, counting from the bottom — the black key between C and D. Press any key below to compare it with its neighbours.
C♯7 on the guitar
C♯7 is above the highest fret of any standard guitar, so a guitar in standard tuning cannot play it.
C♯7 on the staff
Instruments that can play C♯7
9 instruments play C♯7 within the normal range, and 3 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.
Plucked and struck strings
Tuned percussion
Keyboards and free reeds
Only at the extreme of their range
C♯7 is outside the typical range of all six voice types. Test your own range.
The harmonics of C♯7
A played C♯7 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) | 2217.5 Hz | C♯7 | 0¢ |
| 2 | 4434.9 Hz | C♯8 | 0¢ |
| 3 | 6652.4 Hz | A♭8 | +2.0¢ |
| 4 | 8869.8 Hz | C♯9 | 0¢ |
| 5 | 11,087 Hz | F9 | −13.7¢ |
| 6 | 13,305 Hz | A♭9 | +2.0¢ |
| 7 | 15,522 Hz | B9 | −31.2¢ |
| 8 | 17,740 Hz | C♯10 | 0¢ |
Frequently asked questions
What is the frequency of C♯7?
C♯7 is 2217.5 Hz in equal temperament with A4 tuned to 440 Hz, the international standard. At A4 = 432 Hz it is 2177.1 Hz, and at the orchestral A4 = 442 Hz it is 2227.5 Hz.
Is C♯7 the same note as D♭7?
On a piano, a guitar or a tuner, yes: C♯7 and D♭7 are the same key and the same frequency, 2217.5 Hz, in equal temperament. They are two names for one pitch (enharmonic equivalents). Which one is written depends on the key — sharps in sharp keys, flats in flat keys — and a string or wind player may pitch them a few cents apart when playing in just intonation.
How do I play C♯7 on a piano?
C♯7 is key 77 of 88, counting from the bottom — the black key between C and D.
Which instruments can play C♯7?
9 of the instruments we chart play C♯7 within their normal range, including violin, viola, erhu, mandolin, piccolo, and 3 more reach it only at the extreme of their range.
Typing it? C♯7 is also written C#7 or Db7. Convert any frequency on the Hz-to-note converter.