This tool calculates the duty cycle of a pulse.

**What is duty cycle?**

Pulse duty cycle is a fundamental concept in the field of electronics and plays an important role in various applications.

The duty cycle is a measure of the “on” time of a periodic waveform – also known as Pulse Width (**PW**), compared to the total period (**T**) of the waveform expressed as a percentage. This is shown in the picture below.

The formula is given by

**Duty cycle = (PW/T)*100**

where **PW < T**

It is commonly used to describe the behavior of pulse waveforms or signals. A high duty cycle (%) indicates that the signal is on for most of the time, while a low duty cycle means the signal is on for only a small portion of the time.

**Formula and Example Calculation**

Mathematically, the duty cycle is calculated by dividing the duration of the pulse “on” time (also known as the active state or pulse width) by the total duration of the pulse. The result is then multiplied by 100 to express it as a percentage. For instance, if a pulse is on for 2 milliseconds (ms) out of a total period of 10 ms, the duty cycle would be calculated as follows:

Duty Cycle = (2/10) * 100

In this case, the duty cycle would be 20%.

**How is duty cycle measured?**

Duty cycle can be measured using an oscilloscope, a widely used electronic instrument that visually displays the waveform of an electrical signal. By analyzing the waveform on the oscilloscope screen, one can determine the duration of the pulse “on” time and the total period of the waveform. Subsequently, the duty cycle can be calculated using the aforementioned formula.

Before making your measurement, check the oscilloscope bandwidth specifications – both the pulse duration and the rise time matter