A=432 Hz is the best-known alternative to the modern A=440 Hz concert standard. This converter generates the full chromatic scale for any reference pitch you choose, showing every note’s frequency next to its 440 Hz equivalent and the constant cent deviation between the two systems.
How it works
All twelve-tone equal-temperament tunings use the same formula; only the anchor changes.
For a reference A4 and a MIDI note number midi:
frequency = A4 · 2^((midi − 69) / 12)MIDI 69 is A4 itself, so setting A4 to 432 makes that note 432 Hz and scales everything else accordingly. The deviation of the whole system from standard tuning is a single constant:
cents = 1200 · log2(A4 / 440)For A4 = 432 this is about −31.8 cents. Because the shift is a fixed ratio applied to every note, all intervals are preserved — only the absolute pitches move.
Tips and example
In the octave around middle C, A=440 gives C4 at 261.63 Hz and A4 at 440 Hz. Switch the reference to 432 and C4 drops to about 256.87 Hz while A4 sits at 432 Hz, the whole octave roughly 31.8 cents lower.
- The cent deviation is identical for every note, so transposing between systems is uniform.
- Use 415 Hz for Baroque pitch or 442 Hz for some modern orchestras.
- Chords and melodies keep their character; only the overall pitch level changes.
The full table is computed in your browser.
Why some musicians prefer A=432
The preference for 432 Hz is partly aesthetic and partly historical. Proponents describe its sound as warmer or more natural compared with 440 Hz. There is no scientific evidence that 432 Hz has measurable physiological or psychological effects beyond the difference in absolute pitch level, but aesthetic preferences are real and valid.
Historically, concert pitch varied widely before standardisation. In the Baroque era, pitches as low as 415 Hz (roughly one semitone below modern 440) were common, which is why this tool includes 415 as a useful alternative reference. The modern standard of A=440 was formalised internationally in 1939 and confirmed in 1955 by the ISO, making it the near-universal reference for recorded music and instrument manufacturing. Orchestras sometimes tune to 442 or 443 Hz for a brighter ensemble sound, particularly in Central Europe.
Other useful reference frequencies
Beyond A=432 and the standard A=440, this tool supports any reference, including:
| Reference | Common use |
|---|---|
| 415 Hz | Baroque pitch (one semitone below 440) |
| 432 Hz | Alternative modern pitch |
| 440 Hz | ISO standard since 1955 |
| 442 Hz | Common European orchestra tuning |
| 444 Hz | Some ensembles, associated with C=528 Hz |
The math is the same regardless of reference — only the anchor shifts. When playing along with a recording tuned to a non-standard pitch, enter that reference here to find the exact frequency of any note and tune accordingly.
Practical use cases
- Retuning a DAW or software synth: Software instruments often allow custom master tune settings in cents. Use the cent deviation shown here (for example −31.8 cents for A=432) to offset all notes uniformly without retuning each instrument.
- Checking a string instrument: If a luthier or player wants to verify that a gut-strung instrument is at Baroque pitch (415 Hz), the table shows what frequency each open string should read on a tuner.
- Production and mixing: When overdubbing onto a recording made at an unusual pitch standard, matching the reference prevents subtle beating and mistuning in the mix.