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Gravel Calculator

Work out how much gravel, crushed stone, sand, topsoil or mulch to order for a path, driveway, patio base or garden bed, by volume, by weight and in bags. The concrete calculator does the same for poured concrete; this one covers loose materials sold by the yard, the ton or the bag.

Measure in

Sets the weight and bag size below; you can change both.

Area shape

Layer thickness after spreading.

Optional. Add some for compaction or an uneven base.

Weight and bag size

Starting assumptions, not measured values: the weight of a load depends on the stone, grading and moisture. Use your supplier’s figure and the size printed on the bag.

Priced

Optional. Delivery is usually extra.

Result

Material to order

1.85 yd³

About 2.59 tons (2.35 t)

Area
200 ft²
Cubic yards
1.85 yd³
Cubic meters
1.42 m³
Cubic feet
50 ft³
Weight in US tons
2.59 tons
Weight in tonnes
2.35 t
Bags of 0.5 ft³
100
Show the working
  1. Area = length × width20 ft × 10 ft = 200 ft²
  2. Volume = area × depth200 × 0.25 ft = 50 ft³
  3. Cubic yards = cubic feet ÷ 2750 ft³ ÷ 27 = 1.852 yd³
  4. Weight = volume × weight per unit volume1.852 yd³ × 1.4 tons/yd³ = 2.59 tons
  5. 1 US ton = 0.90718474 tonnes2.593 × 0.90718474 = 2.35 t
  6. Bags = volume ÷ bag size, rounded up50 ft³ ÷ 0.5 ft³ = 100

Depth in inches or centimeters is converted to feet or meters first. A US (short) ton is 2,000 lb; a tonne is 1,000 kg. Weights are estimates from the figure under Weight and bag size.

How to estimate gravel, stone and mulch

Loose landscape materials are sold three ways: by volume (cubic yards in the US, cubic meters elsewhere), by weight (tons or tonnes, common at quarries) and in bags. All three start from the same number, the volume of the layer you are spreading.

  1. Pick the material. It loads a starting weight per cubic yard or meter and a bag size, both editable.
  2. Measure the area as a rectangle or a circle. For an irregular bed, split it into pieces and add the results, or find the area with the square footage calculator.
  3. Enter the depth of the finished layer, in inches or centimeters. Add an extra allowance if the material will be compacted or the base is uneven.
  4. Read the volume to order, its estimated weight in US tons and tonnes, the number of bags, and the cost if you enter a price per cubic yard, cubic meter, ton or tonne.

Gravel volume and weight formulas

V = A × D × (1 + extra ÷ 100)

Weight = V × ρ

Bags = ⌈ V ÷ bag size ⌉

A
area: length × width, or π × diameter² ÷ 4 for a circle
D
depth, in the same length unit
ρ
bulk density: tons per cubic yard or tonnes per cubic meter of the loose material
⌈ ⌉
round up to a whole bag

The unit conversions are exact: 1 yd³ = 27 ft³ = 0.764554857984 m³, 1 ft³ = 28.316846592 L, and one US (short) ton is 2,000 lb = 907.18474 kg, so 1 tonne per cubic meter is about 0.8428 tons per cubic yard.

Worked example

A gravel path 20 ft long and 10 ft wide, 3 inches deep, at the starting weight of 1.4 tons per cubic yard:

  1. Area: 20 × 10 = 200 ft²
  2. Volume: 200 × (3 ÷ 12) = 50 ft³
  3. Cubic yards: 50 ÷ 27 = 1.85 yd³ (1.42 m³)
  4. Weight: 1.85 × 1.4 = 2.59 tons, or 2.35 tonnes
  5. Bags of 0.5 ft³: 50 ÷ 0.5 = 100 bags
  6. At $45 per cubic yard: 1.85 × 45 = $83.33, before delivery

The same area in mulch, with 2 ft³ bags, is 50 ÷ 2 = 25 bags. In metric, a 6 × 3 m area 8 cm deep is 18 × 0.08 = 1.44 m³; at 1.7 tonnes per cubic meter that is about 2.45 tonnes (2.7 US tons).

Weight per cubic yard: starting assumptions

We could not find one official table of bulk densities for landscape materials, so the calculator starts from rounded working figures and lets you replace them. Treat them as placeholders until your supplier gives you theirs:

  • Gravel: 1.4 tons per cubic yard (1.7 t/m³)
  • Crushed stone: 1.35 tons per cubic yard (1.6 t/m³)
  • Sand, dry: 1.35 tons per cubic yard (1.6 t/m³)
  • Topsoil: 1.1 tons per cubic yard (1.3 t/m³)
  • Mulch: 0.3 tons per cubic yard (0.35 t/m³)

Real figures move with the rock type, the particle sizes and how they pack, and above all with moisture: wet sand, soil and mulch weigh noticeably more than dry. Quarries that sell by the ton weigh the truck, so the volume you receive depends on their material, not on these numbers.

A load of stone is heavy. Check what your vehicle or trailer is rated to carry before collecting it yourself.

What the estimate leaves out

  • Compaction. Base layers under pavers or a driveway are compacted and end up thinner than the loose material you spread. The extra allowance covers it; how much depends on the material.
  • Minimum orders. Suppliers often deliver in whole or half cubic yards (or tonnes) and may have a minimum load, so the cost shown is for the exact quantity.
  • Poured materials. For concrete slabs and footings, use the concrete calculator. To convert a volume between units, see the volume converter.

Frequently asked questions

How much gravel do I need for a 10x10 area?

At 3 inches deep, a 10 by 10 ft area needs 100 × 0.25 = 25 cubic feet, which is 0.93 cubic yards. At about 1.4 tons per cubic yard that is roughly 1.3 tons, or 50 bags of 0.5 cubic feet.

How many tons are in a cubic yard of gravel?

It depends on the stone and how wet it is. This calculator starts at 1.4 US tons per cubic yard as a working assumption, but you should use the figure your supplier quotes, since they weigh their own material.

How many bags of mulch make a cubic yard?

A cubic yard is 27 cubic feet, so it takes 13.5 bags of 2 cubic feet, which means buying 14. With 3 cubic foot bags it is exactly 9.

How deep should gravel or mulch be?

It depends on the use: a decorative top layer is thinner than a driveway base, which is usually built in compacted layers. Follow the guidance of your supplier or the paver or edging manufacturer for load-bearing work.

How do I convert cubic yards to tonnes?

Multiply the cubic yards by the weight per cubic yard in US tons, then by 0.90718474 to get tonnes. For example 2 cubic yards at 1.4 tons per yard is 2.8 US tons, which is 2.54 tonnes.

Sources

Last reviewed September 19, 2026