FEV1/FVC Ratio Calculator

Formula

To calculate the FEV1/FVC Ratio:

\[ \frac{\text{FEV1}}{\text{FVC}} \times 100 \]

Where:

\(\text{FEV1/FVC}\) is the ratio of Forced Expiratory Volume in 1 second to Forced Vital Capacity (%)
\(\text{FEV1}\) is the Forced Expiratory Volume in 1 second (liters)
\(\text{FVC}\) is the Forced Vital Capacity (liters)

What is FEV1/FVC Ratio?

The FEV1/FVC ratio is a measurement used to assess lung function and diagnose respiratory conditions such as chronic obstructive pulmonary disease (COPD) and asthma. It compares the volume of air that can be forcefully exhaled in one second (FEV1) to the total volume of air that can be exhaled (FVC). A lower than normal FEV1/FVC ratio may indicate the presence of obstructive lung disease.

Example Calculation 1

Let's assume the following values:

FEV1 = 2.5 liters
FVC = 3.0 liters

Step 1: Use the formula:

\[ \frac{2.5}{3.0} \times 100 = 83.33\% \]

The FEV1/FVC Ratio is 83.33%.

Example Calculation 2

Let's assume the following values:

FEV1 = 1.8 liters
FVC = 2.2 liters

Step 1: Use the formula:

\[ \frac{1.8}{2.2} \times 100 = 81.82\% \]

The FEV1/FVC Ratio is 81.82%.