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Bulk Material Tonnage & Allowance Calculator

Estimate bulk material mass and cost with a chosen extra-order percentage.

  • Formula & worked example
  • Private in your browser
  • No signup
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Calculator inputs

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How to use this calculator

  1. Enter the known values in the units shown. Results update as you type.
  2. Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
  3. Use the worked example to check the method. Reset restores the starting fields.

Private by default

Inputs and results stay in this browser tab. Bookify does not upload or store the values you enter.

Formula and method

A 5 by 4 meter area at 10 centimeters deep contains 2 m³. At a custom density of 1,500 kg/m³ it weighs 3 metric tonnes. A 20% allowance raises the order to 3.6 tonnes, costing 180 at 50 per tonne.

Base mass = length × width × depth × density; order mass = base mass × (1 + allowance fraction); cost = order mass × mass price

Worked example

Enter these known values and leave the other values blank.

Material
Enter a custom unit weight
Bulk density
1500 kg/m³
Length
5 m
Width
4 m
Depth
10 cm
Extra-order allowance
20 %
Price per mass unit
50 USD / t
Area
20 m²
Volume
2 m³
Base material mass
3 t
Order mass including allowance
3.6 t
Total cost
180 USD

Assumptions and limitations

  • The model accepts an added allowance from 0% through 30%. Dimensions, density and price must be positive.
  • Use bulk density appropriate to moisture, voids and the loose or compacted condition. The model excludes delivery, minimum orders and taxes unless included in the price.

Common questions

Is an allowance the same as a compaction loss?

No. A 20% allowance multiplies the base mass by 1.20. A 20% loss of delivered material would require a different calculation. Use supplier guidance for loose and compacted quantities.

Does tonne mean a US ton?

A metric tonne is 1,000 kg. A US short ton is 2,000 pounds, or 907.18474 kg. Select the intended mass unit and use the matching unit in the price field.

References

Bookify uses exact customary mass and volume definitions for density units, replacing rounded factors in the reference.

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