Gravel and Bulk Material Calculator
Estimate placed and loose-order volume, material mass, whole bags, payload-based trips and cost from rectangular beds and entered bulk density.
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Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Sum placed rectangular volumes, apply allowance and a loose-volume multiplier, then convert loose material volume to mass with entered density.
Order mass=Σ(L×W×D)×(1+allowance)×loose multiplier×loose bulk density
Worked example
A 10 m × 3 m × 0.1 m bed is 3 m³ placed. With 5% extra, a 1.2 loose multiplier and 1600 kg/m³ loose density, order mass is 6048 kg: 242 bags of 25 kg or at least 7 trips at 1000 kg payload.
Assumptions and input details
Density and loose/placed ratio are user measurements or supplier data, not universal gravel properties. Rows use independent length/width/depth selectors. Bag and trip counts round upward; trips consider mass alone and do not establish vehicle capacity, legal loading or material suitability. Bulk cost uses the selected mass output unit and a single delivery fee.
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
Choose from 23 length definitions, including explicitly labelled regional measures. Area conversions square the length factor; geometric volumes cube it.
The 19 mass definitions distinguish avoirdupois and troy measures, metric and regional measures. Japanese kin is 600 g; mainland Chinese shijin is 500 g.
The 36 volume definitions distinguish US liquid, US dry and Imperial measures. Cups carry an explicit definition. Japanese shō is 2401/1331 L and a gō is one tenth of it; the explicitly labelled 180 mL rice cup is separate.
Regional measures are not interchangeable merely because their names look similar. This is a documented selection, not a claim to include every historical unit.
NIST measurement tables · UK Imperial definitions · Japanese traditional units · Mainland China and Hong Kong unit distinctions
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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