Work out how much gravel, crushed stone, sand, topsoil or mulch an area needs, in yd³, m³, weight and bags.
The gravel you need is the area times the depth, plus a little extra, and the page shows it in cubic yards, cubic metres and cubic feet. A rectangle is length × width, a circle is π × (diameter ÷ 2)², and a triangle is base × height ÷ 2. The depth is divided by 12 in feet and inches, or by 100 in metres and centimetres. The default example is 10 ft by 10 ft at 3 in deep. That is 100 sq ft × 0.25 ft = 25 ft³, and with 10% extra for waste and settling it is 27.5 ft³, which is 1.019 yd³ or 0.779 m³. In metric, 3 m by 3 m at 5 cm deep is 0.45 m³, and 0.495 m³ with 10% extra. A cubic yard is 27 cubic feet and a cubic foot is exactly 0.028316846592 m³. The box under the answer repeats each step with your numbers.
Suppliers often sell by weight, so the page multiplies the volume by a density for the material you pick. The built-in densities are dry gravel at 1680 kg/m³ (105 lb/ft³), dry sand at 1555 kg/m³ (97 lb/ft³), loam as topsoil at 1280 kg/m³ (80 lb/ft³), crushed stone at 100 lb/ft³ (about 1602 kg/m³, from the U.S. EPA volume-to-weight table) and shredded wood chips as mulch at 500 lb per cubic yard (about 297 kg/m³). These are typical values. Wet material is heavier, and a quarry's own stone can differ, so the Density box lets you type the figure from your supplier and the weight follows. In the default example 27.5 ft³ of dry gravel comes to about 2,884 lb, or 1.44 short tons, or 1.31 tonnes.
The extra percentage covers spillage, an uneven base and material that settles when it is compacted. It starts at 10 and you can set it from 0 to 100. Bags are optional: type the volume printed on your bag, in cubic feet or litres, and the page divides the total by it and rounds up. At 0.5 ft³ per bag the 27.5 ft³ example is 55 bags. Leave the bag size empty and no bag count is shown. The page works out volume from a flat area and a single depth. It does not allow for a sloped site, a compacted sub-base, edging or a different depth in different places, so split an uneven site into pieces and add the results.
Bulk loads are usually priced per cubic yard, per tonne or per ton, and bagged material by the bag. Use the cubic yard line to compare bulk prices, the weight line for material priced by weight, and the bag count for a small job. A short ton is 2,000 lb and a tonne is 1,000 kg, and the page shows both so the right one is easy to find. The numbers are estimates worked out from what you type, so check the density and the delivery unit with the supplier before you order.
100 sq ft × 3 in ÷ 12 = 25 ft³, and 25 ÷ 27 = 0.926 yd³. With 10% extra for waste and settling it is 1.019 yd³. In weight, dry gravel at 105 lb/ft³ comes to about 2,884 lb, or 1.44 short tons.
Multiply the cubic yards by the density in pounds per cubic yard and divide by 2,000. Dry gravel at 105 lb/ft³ is 2,835 lb per yd³, so 1 yd³ is about 1.42 short tons. Type your supplier's density in the Density box to get the weight for your load.
Use the area π × (diameter ÷ 2)². A circle 10 ft across has 78.54 sq ft. At 3 in deep that is 19.63 ft³, or 0.727 yd³ before the extra, and 0.800 yd³ with 10% added. Pick Circle and type the diameter.
Divide the total volume by the volume printed on the bag and round up. For 27.5 ft³ and bags of 0.5 ft³ that is 55 bags. Type your bag size, in cubic feet or litres, and the page does the division.
The page starts at 10% for spillage, an uneven base and settling, and accepts 0 to 100. Use 0 for a plain volume. A rough or soft base may need more, so treat the percentage as your own call.
No. The calculation runs in your browser and the sizes stay in this tab. They are not uploaded or stored on your device. Reloading the page puts the example back. The page only counts that a result was shown, without any of your numbers.