Flexible Packaging Roll Calculator

How to Use This Tool

Roll OD to Estimated Footage

Enter the finished roll outside diameter, the core outside diameter, and the material caliper in mils. The calculator will estimate the lineal footage on the roll. If you also enter the web width, it will estimate the MSI per roll.
This section is estimate-based because actual roll build can vary depending on winding tension, caliper variation, material stiffness, and roll hardness.

Feet to MSI

Enter the web width in inches and the total lineal feet. The calculator will return the MSI based on those values.

This section is a direct calculation based on the values entered.

Lbs to MSI

Enter the total roll weight in pounds and the material yield in square inches per pound. The calculator will return the MSI.

This section is also a direct calculation based on the values entered.

Important Note

The Roll OD section gives estimated values only. The Feet to MSI and Lbs to MSI sections are direct calculations, but the accuracy of the result still depends on the accuracy of the values entered.

Flexible Packaging Roll Calculator

Flexible Packaging Roll Calculator

Use this tool to estimate lineal footage from roll OD, convert feet to MSI, and convert pounds to MSI. The roll OD section is estimate-based. MSI calculations are direct calculations based on the values entered.

Roll OD to Estimated Footage

Enter roll OD, core OD, and caliper to estimate feet per roll. Width is optional and will also show estimated MSI per roll.

Estimated Lineal Feet per Roll
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Footage and MSI in this section are estimated values. Actual roll build can vary based on winding tension, caliper variation, and roll hardness.

Feet to MSI

Convert lineal footage and web width into MSI.

MSI
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MSI in this section is calculated directly from the width and lineal feet entered.

Lbs to MSI

Convert roll weight and material yield into MSI.

MSI
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MSI in this section is calculated directly from the weight and yield entered.

Roll Calculator FAQ

  • Roll OD means roll outside diameter. It is the full diameter of the finished roll measured across the center of the roll.

  • It is an estimate because actual roll build can vary based on winding tension, caliper variation, material stiffness, and how tightly the roll is wound.

  • The Feet to MSI and Lbs to MSI sections are direct calculations based on the values entered. The Roll OD section is estimate-based.

  • Caliper should be entered in mils.

  • Width should be entered in inches.

  • No. Width is optional in that section. If you enter it, the calculator will also estimate MSI per roll.

  • Yield is the amount of area a material provides per pound. In this tool, it should be entered as square inches per pound.

  • Use the Feet to MSI calculator when you know the roll footage and width. Use the Lbs to MSI calculator when you know the roll weight and material yield.

  • Yes, as long as the values entered are correct for the material you are working with. Keep in mind that the Roll OD section is still an estimate because roll build can vary.

  • No. This tool is meant to help with planning, estimating, and quick conversions. Final production values should always be confirmed in real operating conditions.

  • Roll OD to Estimated Footage
    Feet = ((OD² - Core²) × π) ÷ (0.048 × Caliper)

    In this formula:

    • OD = roll outside diameter in inches

    • Core = core outside diameter in inches

    • Caliper = material caliper in mils

    This result is an estimate because actual roll build can vary based on winding tension, caliper variation, and roll hardness.

    Estimated MSI from the Roll OD section
    If width is entered in the Roll OD section, the tool also estimates MSI using this formula:
    MSI = Width × Feet × 0.012

    In this formula:

    • Width = web width in inches

    • Feet = estimated lineal feet per roll

    Because the footage is estimated in this section, the MSI is also estimated.

    Feet to MSI
    MSI = Width × Feet × 0.012

    In this formula:

    • Width = web width in inches

    • Feet = lineal feet

    This is a direct calculation based on the values entered.

    Lbs to MSI
    MSI = (Lbs × Yield) ÷ 1000

    In this formula:

    • Lbs = roll weight in pounds

    • Yield = square inches per pound

    This is a direct calculation based on the values entered.