Air to Fuel Ratio (AFR) Calculator

Calculate Air to Fuel Ratio



Formula

To calculate the Air to Fuel Ratio (\(AFR\)):

\[ AFR = \frac{Mair}{Mfuel} \]

Where:

What is an Air to Fuel Ratio?

Air to fuel ratio is a measure of the total mass of the air per unit of mass of fuel used for an engine. Sometimes the air to fuel ratio can be calculated volumetrically, but this is uncommon.

Common Air to Fuel Ratios of Fossil Fuels

Example Calculation 1

Let's assume the following values:

Using the formula:

\[ AFR = \frac{14.7}{1} = 14.7 \]

The air to fuel ratio is 14.7:1.

Example Calculation 2

Let's assume the following values:

Using the formula:

\[ AFR = \frac{34.3}{1} = 34.3 \]

The air to fuel ratio is 34.3:1.