C♯3 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♯3 | vs 440 |
|---|---|---|
| A4 = 415 Hz · Baroque pitch | 130.72 Hz | −101.3¢ |
| A4 = 432 Hz · “Verdi” pitch | 136.07 Hz | −31.8¢ |
| A4 = 440 Hz · Standard (ISO 16) | 138.59 Hz | — |
| A4 = 442 Hz · Orchestral | 139.22 Hz | +7.9¢ |
One cycle of C♯3 lasts 7.215 ms, and its wavelength in air at 20 °C is 2.47 m. Hold it as a steady tone in the tone generator.
C♯3 on the piano
C♯3 is key 29 of 88, counting from the bottom — the black key between C and D. Press any key below to compare it with its neighbours.
C♯3 on the guitar
In standard tuning C♯3 is played in 2 places: 6th (low E) string, fret 9 and 5th (A) string, fret 4. 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 C♯4.
C♯3 on the staff
Instruments that can play C♯3
27 instruments play C♯3 within the normal range, and 1 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.
Bowed strings
Guitars and basses
Woodwind
Keyboards and free reeds
Only at the extreme of their range
Voices: C♯3 is inside the typical range of the bass, baritone and tenor. Test your own range.
The harmonics of C♯3
A played C♯3 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) | 138.59 Hz | C♯3 | 0¢ |
| 2 | 277.18 Hz | C♯4 | 0¢ |
| 3 | 415.77 Hz | A♭4 | +2.0¢ |
| 4 | 554.37 Hz | C♯5 | 0¢ |
| 5 | 692.96 Hz | F5 | −13.7¢ |
| 6 | 831.55 Hz | A♭5 | +2.0¢ |
| 7 | 970.14 Hz | B5 | −31.2¢ |
| 8 | 1108.7 Hz | C♯6 | 0¢ |
Frequently asked questions
What is the frequency of C♯3?
C♯3 is 138.59 Hz in equal temperament with A4 tuned to 440 Hz, the international standard. At A4 = 432 Hz it is 136.07 Hz, and at the orchestral A4 = 442 Hz it is 139.22 Hz.
Is C♯3 the same note as D♭3?
On a piano, a guitar or a tuner, yes: C♯3 and D♭3 are the same key and the same frequency, 138.59 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♯3 on a piano?
C♯3 is key 29 of 88, counting from the bottom — the black key between C and D.
Which instruments can play C♯3?
27 of the instruments we chart play C♯3 within their normal range, including viola, cello, double bass, guitar, 7-string guitar, and 1 more reach it only at the extreme of their range.
Typing it? C♯3 is also written C#3 or Db3. Convert any frequency on the Hz-to-note converter.