How do you calculate cubic yards?

Multiply length by width by depth with all three in feet, then divide by 27. A 10 ft × 10 ft area at 4 inches deep is 10 × 10 × 0.333 = 33.33 cubic feet, and 33.33 ÷ 27 = 1.23 cubic yards.

How many cubic feet are in a cubic yard?

27. A yard is 3 feet, so a cubic yard measures 3 ft × 3 ft × 3 ft, which is 3 × 3 × 3 = 27 cubic feet. That single number is the whole conversion — divide cubic feet by 27, or multiply cubic yards by 27 to go back.

How much does a cubic yard of concrete cover?

At 4 inches thick, one cubic yard covers 81 square feet. At 5 inches it covers 65 sq ft, and at 6 inches, 54 sq ft. The rule is coverage = 324 ÷ thickness in inches.

How much is a yard of concrete?

Ready-mix typically runs somewhere between $140 and $200 per cubic yard delivered in the US, before short-load fees. Suppliers usually add a surcharge below 3 or 4 yards, so a small pour often costs more per yard than a driveway does. Enter your own local price above to get a real figure.

How many cubic yards is a truckload?

A full ready-mix truck carries 8 to 10 cubic yards. Dump trucks hauling soil, mulch or gravel usually run 10 to 15 cubic yards. Below about 3 yards you are into short-load territory and the per-yard price climbs.

Why does the calculator round up to the nearest half yard?

Because that is how suppliers sell it, and because running short mid-pour is far worse than having a wheelbarrow left over. Concrete cannot be topped up an hour later without a visible cold joint, so the trade habit is to order the next half yard up.

Do I need to add extra for waste?

For concrete, add 5 to 10 percent on top of the calculated volume — subgrade is never perfectly level and forms bow slightly under load. For soil and mulch, allow 10 to 15 percent because both settle and compact after placing.

Cubic Yard Calculator for Concrete, Soil and Gravel

Bulk material is ordered by the cubic yard and measured with a tape in feet and inches, and that mismatch is where most over- and under-ordering comes from. Concrete, topsoil, mulch, gravel, sand and fill are all sold this way. The conversion is a single division, but the number you divide by surprises people the first time.

Cubic Yard Calculator formula — The Cubic Yard formula

The cubic yard formula

, and are the length, width and depth all in feet, and 27 is the number of cubic feet in one cubic yard. Depth is usually the one measured in inches, so convert it first:

A 4-inch slab is ft. A 6-inch base is 0.5 ft. A 2-inch mulch layer is 0.1667 ft.

Where the 27 comes from

A yard is three feet, and volume is three dimensions, so every side triples:

This is the same trap as square feet, one dimension worse. Dividing cubic feet by 3 converts nothing — it just produces a smaller wrong number. The factor is 27, and it is worth committing to memory because it comes up on every bulk delivery you will ever order.

For reference, one cubic yard is also 0.7646 cubic metres, 202 US gallons, and roughly the volume of a chest freezer.

Worked example

Take a patio slab 10 ft long, 10 ft wide, poured 4 inches thick.

Step 1 — convert the depth to feet.

Step 2 — multiply the three dimensions for cubic feet.

Step 3 — divide by 27.

Step 4 — round up to what the supplier will actually sell.

At $165 a yard that pour costs $247.50 in material. The quarter-yard of headroom is not waste — it is the margin that covers a subgrade that dipped half an inch in the middle, which every subgrade does.

Cubic Yard Calculator worked example diagram — A visual read of the worked example above — the same numbers the calculator returns for its default inputs.

Coverage: one cubic yard at different depths

A cubic yard is 27 cubic feet, so the area it covers depends entirely on how thick you spread it. Divide 324 by the thickness in inches to get the coverage in square feet:

Thickness	One cubic yard covers
1 in	324 sq ft
2 in	162 sq ft
3 in	108 sq ft
4 in	81 sq ft
5 in	65 sq ft
6 in	54 sq ft
8 in	40.5 sq ft
12 in	27 sq ft

The 324 is just — cubic feet per yard times inches per foot. A 4-inch slab covering 81 square feet is the one worth remembering, because 4 inches is the standard thickness for patios, walkways and garage floors.

Cubic feet to cubic yards conversion table

Cubic feet	Cubic yards
27	1
54	2
81	3
100	3.70
135	5
200	7.41
270	10
500	18.52

Going the other way, multiply cubic yards by 27. In metric, one cubic yard is 0.7646 cubic metres and one cubic metre is 1.308 cubic yards.

Typical depths worth knowing

Job	Usual depth
Concrete patio or walkway	4 in
Concrete driveway (cars)	4 in
Concrete driveway (trucks, RV)	5–6 in
Gravel driveway base	4–6 in
Mulch on beds	2–3 in
Topsoil for new lawn	4–6 in
Sand under pavers	1 in

Depth drives cost far harder than area does, because it multiplies straight through. Going from 4 inches to 6 on a 400 sq ft driveway adds half again to the concrete bill — that is a real decision, not a detail.

How much to order

Suppliers sell in whole and half yards, and most add a short-load fee below three or four yards. Two habits are worth having.

Round up, always. The calculator does this for you at the half yard. A pour that comes up short cannot be rescued by a second truck an hour later — the joint between the two batches will show, and it will be a weak line for the life of the slab.

Add waste on top of the rounding. Five to ten percent for concrete, because forms bow and subgrade dips. Ten to fifteen for soil and mulch, which both settle noticeably in the first month. If you are ordering 6 yards of topsoil for a lawn, order 7.

For a small job it can still be cheaper to mix bags yourself than to pay a short-load fee. The concrete bags calculator works out the bag count, and the crossover is usually somewhere around half a cubic yard.

Common mistakes

Dividing cubic feet by 3. The factor is 27. Three is the length conversion, not the volume one.
Leaving depth in inches. Multiplying 10 × 10 × 4 gives 400, a number in no unit at all. Convert to feet first.
Measuring depth as the finished height. For a slab it is the pour thickness, not the height from the ground to the top of the form.
Ordering the exact calculated figure. Nobody delivers 1.235 yards, and nobody wants to be short.
Forgetting the thickened edge. Many slabs are 4 inches in the field and 8 to 12 at the perimeter. That edge is extra volume — measure it as its own strip and add it.
Ignoring compaction on soil. Loose topsoil settles by roughly 10 to 20 percent once watered in. The hole you are filling needs more than its own measured volume.

Once you have the yardage, the gravel calculator converts it to tons if your supplier prices by weight, and the square footage calculator handles the area step if the shape is anything other than a rectangle.

About the formula: Cubic yards = (Length × Width × Depth) ÷ 27, with all three dimensions in feet. A cubic yard is 3 ft × 3 ft × 3 ft, which is where the 27 comes from.

Cubic Yard Calculator