Select the shape of the Polystyrene and enter the required variables. The calculator will evaluate and display the Polystyrene weight. 

Polystyrene Weight Calculator

Pick the polystyrene type, enter the dimensions, and get the weight.

Sheet / Board
Round / Cylinder
By Volume
Please fill in all dimensions.
Please enter diameter and length.
Please enter a volume.
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Polystyrene Weight Formulas

The following formulas are used to calculate the weight of Polystyrene in different shapes.

Polystyrene Flat Sheet Weight Formula = L * W * T * d

Polystyrene Round Bar Weight Formula = (π/4) * D2 * L * d

Polystyrene Square Hollow Tube Weight Formula = [W2-(W-2T)2] * L * d

Polystyrene Round Hollow Tube Weight Formula = (π/4) * (Do2 - Di2) * L * d

Polystyrene Square Angle Weight Formula = (2*W*T - T2) * L * d

Polystyrene T Bar Weight Formula = (W*T1 + (H-T1)*T2) * L * d

Polystyrene C Channel Weight Formula = (2*W*T1 + (H-2*T1)*T2) * L * d

Variables used in these equations: 

  • L is the length
  • W is the width (or outer width / leg length / flange width, depending on shape)
  • H is the overall height/depth (for T bars and C channels)
  • T is the thickness (sheet thickness, wall thickness, or angle thickness)
  • d is the density
  • D is the diameter (round bar)
  • Do is the outer diameter (round hollow tube)
  • Di is the inner diameter (round hollow tube)
  • T1 is the flange thickness (for T bars and C channels)
  • T2 is the web thickness (for T bars and C channels)

This calculator converts all entered dimensions to inches internally and converts the entered density to lb/in³ internally. You can enter dimensions in inches, mm, cm, m, or ft, and you can enter density in lb/in³, kg/m³, or g/cm³. The result can be displayed in lb, kg, or g.

What is the density of Polystyrene?


Solid (general-purpose) polystyrene is typically about 1.04–1.06 g/cm³ (≈1040–1060 kg/m³, or ≈0.0376–0.0383 lb/in³). Expanded polystyrene (EPS) foams are much less dense (often on the order of ~10–50 kg/m³).