Formula

The Note-to-Frequency Formula

Every note's frequency follows from a single reference point and the equal-tempered scale: f = 440 × 2^((n − 69) / 12), where n is the note's MIDI number (A4 is 69) and 440 is the A4 reference in Hz. Each step of n moves one semitone; twelve steps double the frequency, one full octave. Swap in 432 or 444 for the reference and every note shifts by the same ratio, keeping all the intervals between notes identical.

In practice

How to Use a Note Frequency Chart

Three common uses come up constantly in production and DJing: tuning a synth or sampled instrument to match the key of a track before layering it in, finding the root frequency of a kick drum or bassline so two elements don't fight for the same low-end space, and setting a surgical EQ notch at a note's exact frequency instead of sweeping and guessing. If you already know a track's key but not the underlying frequencies, run it through the Song Key & BPM Finder first, then use this chart to get the exact Hz values to tune to. To see every note in a full scale at once, the scale finder lays out the notes alongside their Camelot and relative keys.

Context

432 Hz vs 440 Hz Tuning

440 Hz has been the international tuning standard since 1955 and is what nearly every DAW, synth, and tuner defaults to. 432 Hz shifts the same equal-tempered scale down by a fixed ratio, roughly 32 cents flatter across every note, and has a following among some producers and listeners who find it warmer, though this is a subjective preference, not a technical advantage; no measurement shows 432 Hz to be more "natural" or in tune than 440 Hz. Some orchestras and mastering engineers tune slightly sharp, to 442 or 444 Hz, for a brighter perceived sound. Whichever reference a track uses, all its internal intervals stay the same; only the absolute pitch shifts.

Frequently Asked Questions