F#4369.994 Hz

F#4 (F-sharp 4) is 369.994 Hz in standard equal temperament at A=440 Hz. It is MIDI note number 66.

F#4 Frequency in All Tuning Systems

Temperament Frequency (Hz) Cents from Equal Common Usage
Equal Temperament 369.994 Hz 0.00 Modern standard; piano, fretted instruments
Pythagorean 371.251 Hz +5.87 Medieval/early music; string ensemble open fifths
Just Intonation (Major) 367.911 Hz -9.77 A cappella vocal, barbershop, Renaissance
Just Intonation (Minor) 367.911 Hz -9.77 Minor-key vocal music, string ensembles
Quarter-Comma Meantone 367.808 Hz -10.26 Renaissance keyboard, early Baroque organ
Third-Comma Meantone 367.080 Hz -13.69 Renaissance vocal music in minor keys
Sixth-Comma Meantone 368.533 Hz -6.85 Baroque orchestral ensemble compromise
Werckmeister III 369.994 Hz 0.00 Baroque keyboard; Bach contemporaries
Werckmeister IV 368.327 Hz -7.82 Baroque keyboard, strong key contrast
Werckmeister V 369.994 Hz 0.00 Specialized Baroque keyboard
Kirnberger III 370.204 Hz +0.98 Classical-era keyboard, keys near C major
Vallotti 369.994 Hz 0.00 Baroque/Classical orchestral tuning
Young (1799) 369.994 Hz 0.00 Classical-era keyboard
Bach/Lehman 370.414 Hz +1.96 Bach keyboard works, Well-Tempered Clavier
Neidhardt 369.994 Hz 0.00 18th century keyboard, near-equal alternative
Kellner (Bach) 369.828 Hz -0.78 Bach keyboard reconstruction

Positive cents = sharper than equal temperament. Negative cents = flatter. 100 cents = 1 semitone.

F#4 at Different Concert Pitches

The same note varies in frequency depending on the concert pitch standard used by your ensemble.

Concert Pitch Frequency (Hz) Common Usage
A = 440 Hz (ISO standard) 369.994 Hz US, UK, and most modern ensembles worldwide
A = 442 Hz 371.676 Hz Many European orchestras; France, Germany
A = 443 Hz 372.517 Hz Berlin Philharmonic; some US orchestras
A = 432 Hz 363.267 Hz Alternative tuning; Baroque revival
A = 415 Hz (Baroque) 348.972 Hz Historically-informed Baroque performance

f = f_at_A440 × (concert_pitch / 440)

Instruments That Play F#4

F#4 (369.994 Hz) falls within the comfortable playing range of 49 instruments.

F#4 and Gb4 — Enharmonic Equivalents

F#4 and Gb4 are enharmonic equivalents — they sound identical at 369.994 Hz but are written differently depending on the musical context.

F#4: F♯ appears in sharp key signatures starting from G major (1 sharp) onward. Common key signatures: G major, D major, A major, E major, B major, F♯ major.

Gb4: G♭ appears as the tonic of G♭ major (6 flats) and in flat key signatures. Common key signatures: G♭ major, D♭ major, C♭ major.

Enharmonic equivalents share the same frequency in equal temperament. In historical temperaments like Pythagorean or meantone, they may differ slightly.

Why F#4 Varies Across Tuning Systems

F#4 shows a maximum deviation of -13.69 cents in Third-Comma Meantone compared to equal temperament. This 14-cent difference reflects how different tuning philosophies prioritize interval purity over equal distribution.

In Third-Comma Meantone, F#4 is tuned flatter than equal temperament, reflecting this system's approach to distributing the Pythagorean comma across the chromatic scale.

2 of the 15 non-equal temperaments deviate by more than 10 cents for F#4, making this note one where tuning system choice has a meaningful impact on pitch.

F#4 Across All Tuning Systems

Explore how F#4 is tuned in each historical temperament system. Each tuning system gives F#4 a slightly different frequency, affecting the harmonic character of chords and melodies.

Tune F#4 with precision — Get Tunable.

Tunable supports 15+ tuning systems including equal temperament, Pythagorean, just intonation, and historical well-temperaments. See exact Hz values in real-time as you play.