Enter the burst strength (kPa) and the grammage (gf/m^2) into the Calculator. The calculator will evaluate the Burst Value (burst index). 

Burst Value (burst index) Formula

BV = BS / G


  • BV is the Burst Value (burst index) (kPa/(gf/m^2))
  • BS is the burst strength (kPa)
  • G is the grammage (gf/m^2)

To calculate Burst Value (burst index), divide the burst strength by the grammage.

How to Calculate Burst Value (burst index)?

The following steps outline how to calculate the Burst Value (burst index).

  1. First, determine the burst strength (kPa). 
  2. Next, determine the grammage (gf/m^2). 
  3. Next, gather the formula from above = BV = BS / G.
  4. Finally, calculate the Burst Value (burst index).
  5. 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.

burst strength (kPa) = 57.4

grammage (gf/m^2) = 24.5

Frequently Asked Questions

What is burst strength and why is it important?

Burst strength is a measure of the pressure required to rupture or puncture a material. It is important in determining the durability and quality of paper, packaging materials, and various products to ensure they can withstand the pressures they will encounter during shipping, handling, and use.

How does grammage affect the burst value?

Grammage, the weight of paper per unit area (usually specified in grams per square meter), directly affects the burst value. Higher grammage typically indicates a thicker or denser material, which can result in a higher burst value, meaning the material can withstand greater pressures before bursting.

Can the burst value formula be applied to materials other than paper?

While the burst value formula is primarily used for paper and packaging materials, it can theoretically apply to any sheet-like materials where burst strength and grammage are relevant factors. However, the formula’s applicability and accuracy might vary depending on the material’s characteristics.

Are there any limitations to using the burst value formula?

The burst value formula provides a straightforward way to assess material strength, but it has limitations. It does not account for factors such as material composition, thickness variations, or environmental conditions, which can all influence burst strength. Therefore, it should be used as a general guide rather than a definitive measure of material durability.