Gravel Calculator
Volume and weight of gravel/crush needed for any area, by length, width, and depth
Frequently Asked Questions
Estimating gravel or crush volume and weight for a project — a driveway, a foundation base, a drainage layer — requires converting a physical area and depth into a volume figure, then applying a density conversion to get weight, since gravel is typically sold and delivered by weight (tonnes) even though the project need is naturally expressed as an area and depth.
Why both volume and weight matter, and why they're calculated separately
The base calculation is straightforward geometry: length times width times depth gives volume. But gravel and crush suppliers typically price and deliver material by weight (tonnes), not volume, which means the volume figure needs a second conversion step using the material's bulk density (weight per unit volume) — a figure that varies somewhat by gravel type and how tightly it's compacted. Skipping this density conversion and ordering by volume alone (or worse, guessing a weight from volume without applying an actual density figure) risks a significant under- or over-order, since the volume-to-weight conversion factor genuinely matters for gravel and crushed stone materials.
A worked example
The same volume of loose gravel and of compacted gravel has meaningfully different weight, since compaction increases how much material fits in a given volume — this is exactly why a bulk density figure specific to the material's actual state (loose vs. compacted) matters for an accurate weight estimate, not just a generic gravel density figure applied uniformly.
How this connects to your other construction calculations
This calculator's volume-then-weight logic parallels the Concrete Calculator's dry-volume conversion approach — both handle the gap between a simple geometric volume calculation and the actual material quantity that needs to be ordered, just for different construction materials with different conversion factors.
Common mistakes
Ordering gravel by rough volume estimation without converting to the weight figure suppliers actually price and deliver by is a common source of under-ordering — always confirm whether a supplier quotes by weight or volume, and use the correct density-based conversion between the two rather than assuming they're interchangeable one-to-one.