How do sound frequency and pitch differ?

In the context of environmental science and acoustics, frequency and pitch are closely related but distinct concepts.

Frequency is a physical property of a sound wave, defined as the number of wavelengths that pass a specific point in space per second. It is measured in hertz (Hz), where 1 Hz equals one cycle per second.12

Pitch is the physiological perception of that frequency by the human ear. While frequency is an objective, measurable physical quantity, pitch is the subjective way our auditory system interprets the "highness" or "lowness" of a tone.132

The relationship between the two is direct: higher frequencies are perceived as higher pitches, while lower frequencies are perceived as lower pitches. Because human hearing is not equally sensitive to all frequencies, environmental noise assessments often use frequency filters—such as the A-weighted scale—to adjust physical sound measurements to better reflect how humans actually perceive the loudness of different pitches.12