2349.32Hz
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2.349 kHzFrequency at A4 = 440 Hz
98MIDI note number
78Piano key (of 88)
14.6 cmWavelength in air
About D7
D7 has a frequency of 2.349 kHz in standard tuning, where A4 is fixed at 440 Hz. It is MIDI note 98 and key number 78 on an 88-key piano.
In equal temperament every semitone multiplies the frequency by the twelfth root of two (≈1.05946), so D7 is 29 semitones above A4: f = 440 × 2^((98 − 69) / 12) = 2,349.32 Hz. The number in the name is the octave in scientific pitch notation, which starts each octave on C.
D7 frequency in different tunings
| Tuning reference | D7 frequency |
|---|---|
| A4 = 440 Hz (ISO 16 standard) | 2.349 kHz |
| A4 = 442 Hz (many European orchestras) | 2.36 kHz |
| A4 = 443 Hz (Berlin, Vienna) | 2.365 kHz |
| A4 = 435 Hz (French diapason normal, 1859) | 2.323 kHz |
| A4 = 432 Hz (alternative tuning) | 2.307 kHz |
| A4 = 415 Hz (Baroque pitch) | 2.216 kHz |
| C4 = 256 Hz (scientific pitch) | 2.299 kHz |
Intervals from D7
| Interval | Note | Frequency | Ratio (just) |
|---|---|---|---|
| Minor second | D♯7 | 2.489 kHz | 16:15 |
| Major second | E7 | 2.637 kHz | 9:8 |
| Minor third | F7 | 2.794 kHz | 6:5 |
| Major third | F♯7 | 2.96 kHz | 5:4 |
| Perfect fourth | G7 | 3.136 kHz | 4:3 |
| Tritone | G♯7 | 3.322 kHz | 45:32 |
| Perfect fifth | A7 | 3.52 kHz | 3:2 |
| Minor sixth | A♯7 | 3.729 kHz | 8:5 |
| Major sixth | B7 | 3.951 kHz | 5:3 |
| Minor seventh | C8 | 4.186 kHz | 9:5 |
| Major seventh | C♯8 | 4.435 kHz | 15:8 |
| Octave | D8 | 4.699 kHz | 2:1 |
Instruments and voices that can play D7
Frequently asked questions
What is the frequency of D7?
D7 is 2.349 kHz when A4 = 440 Hz (2.307 kHz if A4 = 432 Hz).
What MIDI number is D7?
D7 is MIDI note number 98.
Is D7 on a piano?
Yes – it is key 78 of 88.