Gravel Calculator
How much gravel a driveway, path or pad takes — in cubic yards, cubic feet or cubic metres. How it works
Volume needed
cubic yards
- Cubic feet
- 80cu ft
- Cubic metres
- 2.27m³
- Area covered
- 240ft²
- Weight
- tons
Show the calculationHide the calculation3 steps
The working
Area = Length × Width
= 20 ft × 12 ft
= 240 ft²
Volume = Area × Depth
= 240 ft² × 0.333 ft
= 80 cu ft
Cubic yards = Cubic feet ÷ 27
= 80 ÷ 27
= 2.96 cu yd
Enter the area and how deep you want the stone. You get the volume immediately; tons only appear if you supply a density, because gravel weight depends on the stone and how wet it is, and no honest single figure covers every product.
How this calculator works
Only your inputs and exact unit conversions. Where a figure comes from anywhere else, it is recorded below with its source.
- Formula version
- 1.0.0
- Last reviewed
- 2026-09-01
- External data
- None
- Category
- Materials
What this calculates
The volume of stone needed to cover an area to a chosen depth, in cubic yards and the metric and imperial equivalents. That volume is what a supplier quotes and delivers against.
The arithmetic
Area times depth, converted to cubic yards by dividing the cubic feet by 27. A circular area uses π × diameter² ÷ 4. Every entry is converted to feet before anything is multiplied, so you can measure the length in metres and the depth in inches and the result is still right.
Why tons need a density from you
Gravel is sold by volume in some yards and by weight in others, so the conversion matters. But it depends on the stone size, how angular it is, and how much water it is carrying — a wet load can weigh appreciably more than a dry one of the same volume.
Rather than bake in an average that would be wrong for most products, this calculator leaves the density field empty and asks your supplier for the figure. Enter it and the tonnage appears; leave it and the volume answer is unaffected.
Depth in layers
A drive or pad is normally built up in courses — a coarser base beneath a finer surface — rather than as one deep layer of a single product. Run the calculator once per course, at that course's own depth, and order each separately.
A 40 ft × 12 ft driveway, 4 in deep
- Length
- 40 ft
- Width
- 12 ft
- Depth
- 4 in
- 01Depth in feet= 4 in ÷ 12= 0.333 ft
- 02Area= 40 ft × 12 ft= 480 sq ft
- 03Volume= 480 sq ft × 0.333 ft= 160 cu ft
- 04Cubic yards= 160 ÷ 27= 5.93 cu yd
5.93 cubic yards
What it assumes
- 01Constant depth across the whole area, with vertical edges.
- 02The volume is the neat geometric volume of the finished layer, before any compaction.
- 03Unit conversions are exact (1 in = 25.4 mm, 1 cubic yard = 27 cubic feet).
- 04Density and price are used only if you enter them.
What it does not do
- It does not assume a density, so it cannot give tons on its own.
- It does not apply a compaction factor. Stone consolidates under traffic and rolling, and the allowance for that varies by product and specification.
- Irregular areas have to be split into rectangles and circles and added together.
Common questions.
- How many tons of gravel is a cubic yard?
- It depends on the product, so this calculator will not guess. Ask your supplier for the density of the exact stone you are buying, enter it, and the tonnage appears alongside the volume. Stone size, angularity and moisture all move the figure.
- How deep should gravel be for a driveway?
- Deeper than a path, and normally built in layers rather than one lift. Run this calculator once per layer at that layer's depth. Under about two inches, gravel tends to scatter and let the subgrade show through.
- Does this work for pea gravel and crushed stone?
- Yes — the geometry is identical for any loose aggregate. Only the density differs, and that is the figure you supply.
Behind the numbers
The methods and definitions this calculator applies, explained in full and with their sources.
Where people go next
Ordered by what usually comes next in the same job, not by keyword.