Gravel quantity calculator
Estimate gravel or aggregate volume, weight from your density and whole bags; 4 × 3 m at 0.05 m deep with 10 % extra is 0.66 m³.
- Runs in your browser
- No upload
- Instant result
Quantity estimate only. This does not approve structural safety, load capacity, drainage, fire resistance or building-code compliance. Verify the design and local requirements with a qualified professional. Purchase quantities round up to whole packs.
Assumptions & formula
Formula and assumptions
w = Waste allowance/100; V=(ΣLW−Σab)h(1+w); m=Vρ; N=ceil(m/kg)
The prefilled values are editable examples, not product specifications. Enter your supplier’s yield, density, coverage and packaging values, and add an allowance for overlaps, compaction and cuts where needed.
Purchase counts use the exact entered decimals and unit factors, without a rounding tolerance that could discard a real remainder. π and irrational square roots use enclosing bounds; ambiguous counts produce an error. Counts must be safe integers.
Results
Enter values and press Calculate to see the result here.
How to use this calculator
- Set inputs and units
Enter the surface rectangles and the depth, then the supplier’s density in kg/m³ and the pack mass in kg.
- Calculate
Check this worked example: 5×2 m ×0.1 m; density=1600 kg/m³, pack=25 kg,waste=0% →1 m³,1600 kg,64 bags
- Results
Compare the volume, kilograms and tonnes. Changing the density changes the mass without changing the geometric volume.
Questions and limits
Is loose density the same as compacted density?
Not necessarily. Match the supplier’s state to your depth assumptions, and add a deliberate compaction allowance if you need one.
Which input errors should I correct?
Density, depth and pack mass must be positive. Don't enter tonnes in a kilogram field.
What does this calculation leave out?
No bearing capacity, drainage, grading specification, truck load limit or site-engineering assessment.