Note Frequency Calculator
Convert musical notes to frequency in Hz
About this calculator
The Note Frequency Calculator converts musical notes into their corresponding frequencies measured in Hertz (Hz). This tool is essential for musicians, audio engineers, sound designers, and music producers who need precise frequency values for tuning instruments, creating digital audio, or understanding the mathematical relationships between musical pitches. Whether you're working with standard concert pitch (A4 = 440 Hz) or alternative tuning systems, this calculator provides accurate frequency conversions for any note across multiple octaves, making it invaluable for both educational and professional music applications.
How to use
Select the musical note you want to convert from the dropdown menu or input field. Choose the octave number to specify the pitch range. The calculator will instantly display the corresponding frequency in Hz. You can also adjust the reference pitch (typically A4 = 440 Hz) if you're working with alternative tuning standards.
Frequently asked questions
What is the frequency of middle C?
Middle C (C4) has a frequency of approximately 261.63 Hz when using standard concert pitch tuning where A4 equals 440 Hz.
Why is A4 tuned to 440 Hz?
A4 = 440 Hz became the international standard in 1955, though historically other frequencies like 432 Hz were also used for concert pitch.
How do frequencies relate between octaves?
Each octave represents a doubling of frequency. For example, A4 (440 Hz) is exactly double the frequency of A3 (220 Hz).