MetraNestMeasure a uniform layer
Measure the horizontal area to cover, then enter the depth planned for your project. The model assumes a constant depth. If several areas have different depths, calculate them separately and add their volumes. An allowance can represent your reserve; it does not replace measuring irregularities.
Choose litres or kilograms
A bag labelled in litres can be compared directly with the calculated volume. For a bag in kilograms, you need the gravel’s bulk density in its delivery condition. Grain size, voids and compaction change this relationship. The tool therefore leaves this value at zero until you enter it.
Understand the purchased quantity
Bags are rounded up to the next whole number. Compare the purchased quantity with the requirement after allowance: the pack size sometimes already adds a substantial surplus. For a bulk order, the volume in cubic metres remains available in the detailed results. The result does not define a foundation or a permissible transport load.
Volume in m³ = area in m² × depth in cm ÷ 100. Mass in kg = volume × bulk density, only if entered.
A 4 cm layer over 12 m²
With no extra allowance, 12 × 4 ÷ 100 gives 0.48 m³, or 480 L. With 25 L bags, you buy twenty bags, or 500 L. No weight is inferred from this example.
Details to check
- Use the supplier’s actual pack size.
- Keep areas of different depths separate.
- Ask for the material’s bulk density if it is sold by weight.
Frequently asked questions
Why is the density initially blank?
A single value would give false precision for different types of gravel. Kilograms mode requires your product data.
Does the calculation choose the right depth?
No. It converts your project’s depth into volume; it does not recommend the structure of a landscaping project.
Method and references · Editorial review: 25 October 2026
The geometric formulas are explained here. For a product, its packaging dimensions and coverage rate remain the reference inputs.