How Much Gravel Do I Need? Tons per Square Foot and m² Explained

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The quick answer: one ton of gravel covers about 116 square feet at 2 inches deep, or about 58 sq ft at 4 inches. In metric, one tonne covers about 13 m² at 50 mm deep. To find your total, work out the volume of the area and multiply by the weight of the gravel.

This guide shows the formula, how deep to lay gravel for paths and driveways, and a full worked example. For an instant answer, use the gravel and mulch calculator, which gives the result in cubic yards, tons, m³ and tonnes.

Gravel coverage at a glance

The table uses typical densities of 1.4 tons per cubic yard and 1.5 tonnes per m³ for crushed stone and pea gravel. Heavier stone such as granite covers a little less.

DepthCoverage per ton (US)DepthCoverage per tonne (metric)
1 in230 sq ft25 mm27 m²
2 in116 sq ft50 mm13 m²
3 in77 sq ft75 mm9 m²
4 in58 sq ft100 mm6.7 m²
6 in39 sq ft150 mm4.4 m²

The formula

  1. Measure the area. Length × width.
  2. Multiply by the depth to get the volume. Convert inches to feet (divide by 12) or millimetres to metres (divide by 1,000) first.
  3. Convert to cubic yards if you work in feet. Divide cubic feet by 27.
  4. Multiply by the density to get the weight: about 1.4 tons per cubic yard or 1.5 tonnes per m³.
  5. Add 5–10% for uneven ground and compaction.

Worked example: a gravel driveway

Take a driveway 10 ft wide and 50 ft long with a 4 inch layer of gravel:

  • Area: 10 × 50 = 500 sq ft
  • Volume: 500 × (4 ÷ 12) = 167 cubic feet
  • Cubic yards: 167 ÷ 27 = 6.2 yd³
  • Weight: 6.2 × 1.4 = 8.7 tons
  • With 10% extra: about 9.5 tons

The same job in metric, for a driveway 3 m wide and 15 m long at 100 mm deep:

  • Volume: 3 × 15 × 0.1 = 4.5 m³
  • Weight: 4.5 × 1.5 = 6.75 tonnes
  • With 10% extra: about 7.4 tonnes

How deep should gravel be?

ProjectRecommended depth
Decorative borders and beds1–2 in (25–50 mm)
Garden paths2 in (50 mm)
Patio or seating area2–3 in (50–75 mm)
Driveway top layer2–3 in (50–75 mm) over a compacted base
Driveway base (crushed stone / MOT Type 1)4–6 in (100–150 mm)

Going deeper than recommended on a path is a false economy. Loose gravel more than about 2 inches deep is hard to walk on and gets kicked about. For driveways, the strength comes from the compacted base, not from a thick top layer.

Bulk bags, loose loads and small bags

  • Bulk (jumbo) bags in the UK usually hold 750–900 kg. A typical 850 kg bag covers around 11 m² at 50 mm.
  • Loose loads by truck are sold by the ton, tonne or cubic yard and are the cheapest option for driveways.
  • Small bags of 20–25 kg or 0.5 cu ft are fine for a border, but you would need around 40 of them for a single tonne.

Common mistakes

  • Forgetting to convert inches to feet before multiplying.
  • Ordering the top layer only and forgetting the sub-base.
  • Not allowing for compaction: a crushed stone base can settle by 10–15% once rolled.
  • Skipping weed membrane under decorative gravel, then losing stone into the soil.

Frequently asked questions

How many square feet does a cubic yard of gravel cover?

About 324 sq ft at 1 inch, 162 sq ft at 2 inches, 108 sq ft at 3 inches and 81 sq ft at 4 inches.

How much does a cubic yard of gravel weigh?

Usually 2,600–3,000 lb, or roughly 1.3–1.5 tons, depending on the stone and how wet it is.

Is pea gravel the same weight as crushed stone?

They are close. Pea gravel is round and does not lock together, so it is better for paths and play areas. Angular crushed stone compacts firmly and is the right choice for driveways.

How much gravel for a 10×10 area?

At 2 inches deep, a 10 × 10 ft area needs about 0.62 cubic yards, or just under 0.9 tons.

Related: the DIY Project Budget & Materials Planner turns your measurements into quantities, costs and a shopping list.

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