How note frequency is calculated
Equal temperament uses A4 as the reference point. Each semitone changes frequency by the twelfth root of two, so every 12 semitones doubles or halves the frequency.
Music reference
Note Frequency Calculator and A4 Tuning Reference
Choose a note, octave, and A4 tuning reference to calculate frequency in Hz. Browse a full octave table for synthesis, tuning, EQ, and music theory work.
Adjustable A4 reference
Use 440 Hz or change the reference for alternate tuning standards.
Note and octave lookup
Convert any chromatic note from low bass to high soprano range.
Producer-friendly table
Use the frequency chart for synth oscillators, EQ targets, tuning, and sound design.
Note Frequency Calculator
Convert notes to Hz with an adjustable A4 tuning reference.
A4
440.00
Hz
C4
261.6 Hz
C#4
277.2 Hz
D4
293.7 Hz
D#4
311.1 Hz
E4
329.6 Hz
F4
349.2 Hz
F#4
370.0 Hz
G4
392.0 Hz
G#4
415.3 Hz
A4
440.0 Hz
A#4
466.2 Hz
B4
493.9 Hz
Workflow
How to use Note Frequency Calculator
1
Pick a note
Choose the note name and octave you want to calculate.
2
Set A4 reference
Keep 440 Hz or enter another concert pitch reference.
3
Read the frequency
Use the Hz value or scan the octave table for nearby notes.
Using note frequencies in production
Frequency charts help producers tune synth oscillators, identify resonances, set pitch references, and understand where notes sit in the spectrum. They are also useful alongside a pitch detector or tuner.
Frequently Asked Questions
A4 is usually 440 Hz, but some orchestras and productions use a slightly different reference.
With A4 at 440 Hz, middle C (C4) is about 261.63 Hz.
Yes. Change A4 from 440 Hz to any practical reference value and the table updates.
An octave is a 2:1 frequency ratio, so A5 is twice A4 and A3 is half A4.
Use Note Frequency Calculator inside your Vocuno workflow
Keep quick pitch and tempo checks next to AI vocals, stem separation, voice conversion, and the Studio editor.
Open frequency calculator