Convert Frequency from hertz (Hz) to other units
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What Is a Hertz (Hz)?

Hertz (Hz) is the standard unit of frequency, measuring the number of cycles per second.

You encounter it everywhere in modern technology, from the sound you hear and the screen you're looking at to the speed of your computer's processor (CPU). The plural form is simply hertz.

Who Was Heinrich Hertz?

The unit is named in honor of the German physicist Heinrich Rudolf Hertz.

In the late 1880s, he was the first person to provide conclusive proof of the existence of electromagnetic waves. His groundbreaking experiments laid the groundwork for the development of radio, television, and all forms of wireless communication.

What Is Hertz Used For in Everyday Technology?

Hertz is a fundamental measurement you encounter in everyday technology, often without realizing it. Here are two of the most common examples:

Sound Waves and Pitch

A sound's pitch is determined by its frequency (measured in hertz): higher frequencies produce higher pitches.

For example, the A above middle C on a piano is standardized at 440 Hz.

Screen Refresh Rates (60 Hz vs. 120 Hz)

The refresh rate of your computer monitor, TV, or smartphone screen is measured in hertz.

This number indicates how frequently the display updates the image per second—a higher value results in smoother motion, which is especially noticeable in videos and gaming.

• 60 Hz: Updates the image 60 times per second. This is the standard for most displays.
• 120 Hz: Updates 120 times per second for much smoother on-screen movement, making it great for gaming.
• 240 Hz: Updates 240 times per second, offering exceptionally fluid motion for professional and competitive gamers.

What Does Gigahertz (GHz) Mean for Computers?

When discussing computer processors, you often hear the term gigahertz (GHz). One gigahertz is equal to one billion hertz (1 GHz = 10⁹ Hz).

This value represents the processor's CPU clock speed—the number of processing cycles it can execute per second.

Before gigahertz became the standard, speeds were often measured in megahertz (MHz), where 1 GHz equals 1,000 MHz. While not the sole indicator of performance, a higher clock speed generally means a processor can perform calculations and execute instructions more quickly.