Cubic Yard Calculator

Use this cubic yard calculator to find how much mulch, soil, gravel, sand or concrete a job needs before you order. Enter the length, width and depth of each area, and it gives you the volume in cubic yards, cubic feet and cubic metres. Unlike most yardage calculators, it adds up several areas of different shapes and depths in one go, then turns the total into bags, tons and a cost.

About the cubic yard calculator

Bulk landscape and building materials are sold by the cubic yard in the US. Your tape measure works in feet and inches. The gap between the two is where orders go wrong: people forget to convert the depth from inches, or measure one big rectangle when the space is really three shapes.

• Several areas, one total. Add up to 20 rows. A lawn, two flower beds and a round tree ring can all go in one estimate.
• Five shapes. Rectangle, circle, triangle, ring (a border around a circle), or an area you already know in square feet.
• A different depth for each area. Mulch at 3 inches in one bed and gravel at 4 in another are no problem.
• Extra for waste. Add a percentage and the order figure includes it.
• Bags, weight and cost. Pick a bag size for a bag count, enter your supplier’s weight per yard for tons, and a price per yard for the bill.
• Metric too. Switch to metres and centimetres; the numbers you typed convert automatically.

It runs in your browser. Nothing you enter is sent anywhere or saved.

How to use the cubic yard calculator

1. Choose your units. Feet with depth in inches is the default. Metres with depth in centimetres is the alternative.
2. Enter the first area. Pick its shape, then type the measurements and the depth of material you want.
3. Add more areas. Press “Add another area” for each separate space. If you have several identical areas, such as three raised beds, enter one and set “How many” to 3.
4. Add extras if you want them. A waste percentage, a bag size, a price per cubic yard and a weight per cubic yard are all optional.
5. Read the result. The big number is the cubic yards to order. The table beneath shows what each area contributes.

The cubic yard formula

A cubic yard is a cube 3 feet long, 3 feet wide and 3 feet tall. That’s 3 x 3 x 3 = 27 cubic feet. So the formula is:

Cubic yards = length (ft) x width (ft) x depth (ft) / 27

Depth is usually measured in inches, and there are 12 inches in a foot. Folding that in gives the shortcut most landscapers use:

Cubic yards = square feet x depth in inches / 324

The 324 is just 27 x 12. The cubic yard calculator uses the same arithmetic for every shape: it finds the surface area, multiplies by the depth, and divides by 27.

Area formulas for each shape

For an L-shaped patio or a bed with a curved end, split it into simple shapes and add a row for each. Two rectangles make an L. A rectangle plus half a circle makes a rounded end: enter the circle and then halve its depth, or enter the half-circle’s area directly.

How to measure before you use the cubic yard calculator

Good measurements matter more than the arithmetic. A few habits make the answer trustworthy:

• Measure the area you’ll fill, not the plot. Leave out the tree trunk, the stepping stones and the path through the middle.
• Use the longest and widest points for a rough bed, then accept that the answer runs slightly high. That’s safer than running short.
• Convert odd inches to decimals. 10 ft 6 in is 10.5 ft. 10 ft 3 in is 10.25 ft. Divide the inches by 12.
• For a circle, measure straight across the middle. If you can only reach from the centre to the edge, double it.
• Check the depth you have already. Topping up 1 inch of old mulch to 3 inches takes a 2-inch layer, not 3.

Reading your result

The cubic yard calculator shows several figures. Here’s what each one is for.

• Cubic yards. The figure to give a bulk supplier. It includes your waste percentage if you set one.
• Cubic feet. The figure to use when you’re buying bags, since bags are labelled in cubic feet.
• Cubic metres. For suppliers who work in metric.
• Bags. Appears when you pick a bag size. Always rounded up to a whole bag.
• Weight. Appears when you enter a weight per cubic yard. Useful for delivery limits and for materials sold by the ton.
• Cost. Appears when you enter a price per cubic yard. It covers material only.
• Area by area. One line per row, so you can see which space is using the most and catch a typo.

Open “Show the working” to see each step written out. If a number looks wrong, the working shows where it came from.

Cubic yard calculator example: mulch for a flower bed

A bed measures 10 ft by 10 ft and you want 3 inches of mulch.

1. Surface: 10 x 10 = 100 square feet.
2. Volume: 100 x 3 / 324 = 0.93 cubic yards, which is 25 cubic feet.
3. In 2 cubic foot bags: 25 / 2 = 12.5, so 13 bags.

One cubic yard would cover this bed with a little to spare. If you’re buying bags, 13 bags does it exactly.

Example: three areas in one order

A front garden has a 20 x 4 ft border, a round bed 10 ft across, and a triangular corner 10 ft along the base and 8 ft deep. All get 3 inches of mulch.

That’s 1.84 cubic yards, or 25 bags of 2 cubic feet. At $38 a yard in bulk, it comes to $69.86 before delivery. Doing this with a single-shape calculator means three separate sums and adding them yourself.

Example: a gravel driveway

A driveway 40 ft long and 12 ft wide gets 4 inches of gravel: 480 x 4 / 324 = 5.93 cubic yards. Gravel compacts and spreads unevenly, so add 10% and the order becomes 6.52 cubic yards. A supplier who sells by the half yard would round that to 7.

Example: a concrete patio

A 12 x 12 ft patio poured 4 inches thick needs 144 x 4 / 324 = 1.78 cubic yards, which is 48 cubic feet. That’s a small ready-mix order, or a lot of bags:

• 80 lb bags yield 0.60 cubic feet each: 48 / 0.60 = 80 bags.
• 60 lb bags yield 0.45 cubic feet each: 107 bags.

With 10% extra for spillage and uneven ground, it’s 1.96 cubic yards and 88 bags of 80 lb mix. The yields are from Quikrete’s data sheet for its standard concrete mix. Other brands and mixes differ, so check the bag.

How much one cubic yard covers

Turn the formula round and you get coverage: 324 divided by the depth in inches.

So a 3-inch layer of mulch from one cubic yard covers a bed of about 10 by 11 feet. Double the depth and you halve the coverage.

Square feet to cubic yards

Square feet alone can’t become cubic yards. You need a depth. This table does the sum for common sizes; for anything else, choose “I know the area” in the cubic yard calculator and type your square footage.

All figures are cubic yards with nothing added for waste.

Converting other units to cubic yards

Bags per cubic yard

Mulch, soil and decorative stone are bagged by volume, so the bag tells you its cubic feet. Concrete is bagged by weight, and the volume it makes once mixed is the yield printed on the bag. The cubic yard calculator always rounds bags up, because you can’t buy part of one.

Bags or bulk? Compare the price per cubic yard. A 2 cubic foot bag at $4 works out to $54 a yard (13.5 bags). If bulk costs less than that delivered, bulk wins, and it usually does once you need more than a yard or two.

Cubic yards to tons

Stone, sand and gravel are often priced by the ton, and delivery trucks have weight limits, so you may need the weight as well as the volume. There’s no single conversion: a cubic yard of dry mulch weighs a fraction of a cubic yard of gravel, and wet material weighs more than dry.

The one figure that’s fairly fixed is concrete: about 150 lb per cubic foot, so about 4,050 lb, or roughly 2 tons, per cubic yard. For everything else, ask your supplier for their weight per cubic yard and type it into the weight box. A 10 x 10 ft area filled 3 inches deep with a material at 2,400 lb per yard weighs 2,222 lb, or 1.11 tons.

Choosing a depth

• Mulch: 2 to 3 inches is the usual range for beds. Deeper than that can smother plants.
• Topsoil for a new lawn: often 4 to 6 inches, depending on what’s underneath.
• Raised beds: the full height of the bed. Three beds of 4 x 8 ft filled 12 inches deep need 3.56 cubic yards.
• Concrete: 4 inches is the common thickness for patios and walkways. Driveways and anything load-bearing follow your plans or local code.
• Gravel and base stone: follow the spec for the job; base layers under pavers and driveways are compacted, which uses more material than the loose depth suggests.

Measure depth in a few places. Ground is rarely level, and an area that averages 4 inches when you planned for 3 needs a third more material.

What the cubic yard calculator doesn’t know

It does geometry. It doesn’t know your material or your site, so a few things stay with you:

• Compaction. Base stone and soil pack down when you tamp or roll them. How much depends on the material. Use the waste box for it, with a figure from your supplier or your plans.
• Density. We don’t ship a table of material weights, because published figures for the same material vary widely with moisture and grading. Your supplier’s number for their product is the one to use.
• Slopes and uneven ground. The depth you enter is treated as uniform. On a slope, use the average of a few depth measurements.
• Structural concrete. Thickness, reinforcement and mix strength for footings, slabs and driveways come from your plans or local building code, not from a volume estimate.
• Minimum orders and delivery. Ready-mix plants and bulk yards often have a minimum load or a short-load fee. The cost box multiplies yards by price and nothing else.

Common mistakes

1. Leaving depth in inches. 10 x 10 x 3 is not 300 cubic feet; 3 inches is 0.25 feet. The calculator takes depth in inches so you don’t have to convert.
2. Dividing by 3, or by 9. There are 3 feet in a yard and 9 square feet in a square yard, but 27 cubic feet in a cubic yard.
3. Using radius for diameter. The circle shape asks for the full width across. Entering the radius gives a quarter of the right answer.
4. Forgetting compaction and settling. Loose material packs down. That’s what the waste allowance is for.
5. Ordering the exact figure. Round up to what the supplier sells, usually half yards.

Working in metres

Switch the units to metres and the cubic yard calculator takes lengths in metres and depth in centimetres. A 5 x 4 m area filled 10 cm deep is 2 cubic metres, which is 2.62 cubic yards. One cubic yard is exactly 0.7646 cubic metres, because a yard is defined as 0.9144 metres. The result always shows both, so you can order from a supplier who works in either.

More project calculators

Building a wall on that new slab? Our concrete block calculator counts the blocks, mortar and core fill. For paving, the bitumen calculator works out asphalt and aggregate for a driveway or road. If the job is a pool, the pool salt calculator tells you how many bags of salt to add. And to turn your quantities into a quote, use the job estimate calculator.

Sources

• The yard is defined as exactly 0.9144 metres, so 1 cubic yard = 27 cubic feet = 0.764554857984 cubic metres.
• Quikrete, Concrete Mix data sheet (No. 1101): bag yields of 0.30, 0.375, 0.45 and 0.60 cubic feet for 40, 50, 60 and 80 lb bags.