Soil Calculator (Cubic Yards, Bags and Weight)
Find how much soil, garden mix or fill dirt you need for a raised bed or lawn. Enter the area and depth to get cubic yards, bags of 0.75 to 1.5 ft3, weight and cost.
Leave blank for 1.
Spillage and uneven ground. Blank counts as 0.
Typical value. Ask your supplier. Blank hides the weight.
Blank hides the truck loads.
In your own currency.
Enter the dimensions to see the volume.
About the soil calculator
The Soil Calculator estimates how much soil it takes to fill a raised bed, a planter, a round garden bed or a hole. Pick a shape, enter the dimensions and the depth, and it returns the volume in cubic yards, cubic feet, cubic metres and litres. It also shows the weight, the number of bags and the number of truck loads, so you can decide whether to buy bagged soil or order a delivery.
It is useful for any job where you fill a space with garden mix, potting soil, compost blends or plain fill dirt. Because every length has its own unit, you can measure a bed in feet, a planter in inches and a pot in centimetres without converting anything first.
How to calculate soil volume
Steps
- Choose the shape. Rectangle suits most raised beds. Circle covers round beds, barrels and cylindrical planters. Triangle and trapezoid cover corner and tapered beds, and known area takes a number you already have.
- Enter the measurements, picking a unit for each length.
- Enter the depth, which is the fill height inside the bed or container. It is set to inches by default.
- Set the quantity if you are filling several identical beds or pots.
- Add a waste allowance if you want a margin for settling or spillage. It starts at zero.
- Edit the density if your supplier gives one, and add a price to see an estimated cost.
Formulas
For a rectangular bed:
For a round bed or a cylindrical planter, with as the diameter:
Cubic feet become cubic yards by dividing by 27:
Worked example: a raised bed
A raised bed is 8 ft long, 4 ft wide and filled 12 inches deep. The volume is 8 x 4 x 1 = 32 cubic feet. That is 1.19 cubic yards, or about 0.91 cubic metres. At the default density of 1.1 US tons per cubic yard, the weight comes to about 1.3 US tons. Four such beds would be set as a quantity of 4, giving 128 cubic feet or 4.74 cubic yards.
Worked example: a round bed and a planter
A circular bed 6 ft across and 8 inches deep has an area of about 28.3 square feet. At a depth of 8/12 ft, the volume is about 18.85 cubic feet, or 0.70 cubic yards.
A cylindrical planter 2 ft across and filled 18 inches deep has a base area of about 3.14 square feet and a volume of 4.71 cubic feet, which is about 133 litres. This is helpful when a bag is labelled in litres or quarts and you need to know how many bags will fill the pot. For liquid or container sizes in other units, the Volume Converter is handy.
Choosing a fill depth
These are typical values, not requirements. Check what your plants need.
- Raised beds: about 6 to 12 inches, deeper for root vegetables.
- New lawn or regrading: about 4 to 6 inches of topsoil.
- Containers: fill to a little below the rim so water does not spill over.
Soil settles after watering, so consider adding 5 to 10 percent. Use the waste allowance field for that.
Bags, bulk and weight
The calculator lists bags of 0.75, 1 and 1.5 cubic feet and a 40 lb bag, which is about 0.75 cubic feet. Bag counts are rounded up. For one cubic yard you would need roughly 36 bags of 0.75 cubic feet, or 27 bags of 1 cubic foot. Bag sizes vary, so read the label, and ask the supplier how they measure bulk loads.
For bigger jobs the truck load figure divides the volume by a capacity you can edit, with 10 cubic yards as the default. If you compare a bag price with a bulk price, the Unit Price Calculator puts both on the same footing.
Weight matters for moving soil and for decks, roofs and balconies. The 1.1 US tons per cubic yard default is a typical figure only. Moist soil is heavier than dry soil, and mixes with compost or perlite are lighter, so edit the density field. The Mass Converter converts between tons, tonnes, pounds and kilograms.
Accuracy and limits
Results are estimates. Beds are rarely exactly the size you measured, and soil compacts after it is watered. Round up when in doubt, and keep any leftover for topping up. If you only need the footprint of a bed, the Area Calculator will give it to you.
Privacy
Nothing is uploaded; every calculation runs in your browser and never leaves your device.
Related tools
For lawns and regrading, see the Topsoil Calculator. To cover the finished bed, use the Mulch Calculator, and for paths or drainage layers, the Gravel Calculator. To work out the volume of a large round container, try the Tank Volume Calculator.
Frequently asked questions
How do I calculate how much soil a raised bed needs?
Multiply length, width and fill depth to get cubic feet, then divide by 27 for cubic yards. A bed 8 ft by 4 ft filled 12 inches deep holds 32 cubic feet, or about 1.19 cubic yards.
How do I work out soil for a round bed or a cylindrical planter?
Choose the circle shape and enter the diameter and depth. The volume is pi times the radius squared times the depth, so a planter 2 ft across and 18 inches deep holds about 4.71 cubic feet, or roughly 133 litres.
How deep should a raised bed be filled?
A typical raised bed is filled 6 to 12 inches deep, with deeper beds for root crops. This is a rule of thumb, so check what your plants need and leave a little room below the rim.
How many bags of soil make a cubic yard?
A cubic yard is 27 cubic feet, so it takes about 36 bags of 0.75 cubic feet or 27 bags of 1 cubic foot. Bag sizes vary, so read the label and let the calculator round up for your actual volume.
How much does a cubic yard of soil weigh?
The default is 1.1 US tons per cubic yard, which is only a typical figure. Moist soil weighs more than dry soil and mixes with compost are lighter, so edit the density field if you know the real value.
How is this different from the topsoil calculator?
It uses the same calculation and gives the same results. This page is set out for beds, planters and fill dirt, while the topsoil page focuses on lawns and regrading.
Is my data sent anywhere?
No. The raised bed, planter and fill soil sums run in your browser, so your sizes, densities and prices are never uploaded or stored on a server. They stay on this device and are not shared with anyone.