Clock Cycle

A clock cycle, or simply a "cycle," is a single electronic pulse of a CPU. During each cycle, a CPU can perform a basic operation such as fetching an instruction, accessing memory, or writing data. Since only simple commands can be performed during each cycle, most CPU processes require multiple clock cycles.

In physics, the frequency of a signal is determined by cycles per second, or "hertz." Similarly, the frequency of a processor is measured in clock cycles per second. Since modern processors can complete millions of clock cycles every second, processor speeds are often measured in megahertz or gigahertz.

The frequency of a processor is also known as the processor's clock speed. While the clock speed is important in determining the processor's overall performance, it is not the only factor. Since processors have different instruction sets, they may differ in the number of cycles needed to complete each instruction, or CPI (cycles per instruction). Therefore, some processors can perform faster than others, even at slower clock speeds.

Updated July 24, 2010 by Per C.

quizTest Your Knowledge

What is the first natural number?

Correct! Incorrect!     View the Natural Number definition.
More Quizzes →

The Tech Terms Computer Dictionary

The definition of Clock Cycle on this page is an original definition written by the team. If you would like to reference this page or cite this definition, please use the green citation links above.

The goal of is to explain computer terminology in a way that is easy to understand. We strive for simplicity and accuracy with every definition we publish. If you have feedback about this definition or would like to suggest a new technical term, please contact us.

Sign up for the free TechTerms Newsletter

How often would you like to receive an email?

You can unsubscribe or change your frequency setting at any time using the links available in each email.

Questions? Please contact us.