Enter the initial and final cross-sectional areas into the calculator to determine the extrusion ratio. This ratio is a measure of the degree of deformation in the extrusion process.

Extrusion Ratio Formula

The following formula is used to calculate the extrusion ratio:

ER = A₀ / A₁


  • ER is the extrusion ratio
  • A₀ is the initial cross-sectional area (square inches)
  • A₁ is the final cross-sectional area (square inches)

To calculate the extrusion ratio, divide the initial cross-sectional area by the final cross-sectional area.

What is an Extrusion Ratio?

The extrusion ratio is a dimensionless number that represents the amount of deformation a material undergoes during the extrusion process. It is calculated by dividing the initial cross-sectional area of the billet by the final cross-sectional area after extrusion. A higher extrusion ratio indicates a greater degree of deformation and can affect the mechanical properties of the extruded product.

How to Calculate Extrusion Ratio?

The following steps outline how to calculate the Extrusion Ratio.

  1. First, determine the initial cross-sectional area (A₀) in square inches.
  2. Next, determine the final cross-sectional area (A₁) in square inches.
  3. Use the formula ER = A₀ / A₁ to calculate the Extrusion Ratio (ER).
  4. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem:

Use the following variables as an example problem to test your knowledge.

Initial cross-sectional area (A₀) = 4 square inches

Final cross-sectional area (A₁) = 1 square inch