Gravel Calculator

Work out how many tonnes and cubic metres of gravel or crushed stone you need for a driveway or path, plus the cost — from the area and depth. Free, instant, no sign-up.

Area & depth

Price

Your gravel estimate

Area15,0 m²
Volume0,75 m³
Gravel needed1,13 t
≈ bulk bags (1 t)2 bags
Estimated gravel costR 394

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How the gravel calculation works

volume (m³)      = length × width × (depth_mm ÷ 1000)
gravel (tonnes)  = volume × 1.5 (t/m³)
bulk bags        = ⌈tonnes⌉  (1-tonne bags)
gravel cost      = tonnes × price per tonne

FAQ

How do I calculate how much gravel I need?
Multiply the area by the depth to get the volume in cubic metres, then multiply by the gravel density (about 1.5 tonnes per m³) to get the weight. This calculator does it and estimates the cost.
How many tonnes of gravel are in a cubic metre?
Crushed stone and gravel weigh roughly 1.5 tonnes per cubic metre, so 1 m³ ≈ 1.5 t. Wet or fine material weighs a little more.
How deep should a gravel driveway be?
A gravel top layer is usually 40–60 mm over a compacted sub-base. Deeper for heavy vehicles or soft ground.
Does this include the sub-base?
This estimates the gravel layer you enter. Create a free BuilderBuddi account to build the full driveway estimate with sub-base, edging, and labour.

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