Cubic Yards Calculator

What is a cubic yard?

A cubic yard is a unit of volume equal to the space inside a cube that measures three feet on each side. Because 3 × 3 × 3 equals 27, one cubic yard contains exactly 27 cubic feet. The cubic yard is the standard volume unit used across the construction and landscaping industries in the United States for ordering and delivering bulk materials.

When suppliers quote prices for concrete, gravel, mulch, topsoil, sand, or fill dirt, the price is almost always given per cubic yard. Understanding how to calculate cubic yards from your project dimensions is essential for accurate ordering and cost estimation.

The cubic yards formula

To calculate cubic yards, first find the volume in cubic feet by multiplying length, width, and depth in feet. Then divide by 27, because one cubic yard equals 27 cubic feet. This two-step process works for any rectangular area such as a patio slab, garden bed, driveway, or foundation footing.

If your depth is measured in inches rather than feet, divide by 12 first to convert to feet before multiplying by the other dimensions. Many construction projects specify slab or fill depth in inches — for example, a 4-inch concrete slab or a 3-inch mulch layer — so this conversion step is common.

For circular areas such as tree rings, round patios, or cylindrical post holes, calculate the area in square feet using π × radius² and then multiply by the depth in feet before dividing by 27. For irregular shapes, break the area into simpler rectangles or triangles, calculate each section separately, and sum the cubic yardage.

Ordering bulk materials

Most bulk construction materials are sold by the cubic yard. Knowing the cubic yardage of your project area lets you order the right amount of concrete, gravel, mulch, or soil without significant waste or shortfall. Under-ordering means an extra delivery trip and potential delays; over-ordering wastes money and leaves excess material to dispose of.

It is common to add 5 to 10 percent extra to account for compaction, spillage, uneven ground, and slight measurement inaccuracies. For gravel and crushed stone, compaction can reduce volume by 10 to 15 percent after settling, so experienced contractors often order on the higher end of that margin. For mulch, which is lighter and less prone to compaction, 5 percent extra is usually sufficient.

Suppliers may not sell fractions of a cubic yard. If your calculation yields 4.3 cubic yards, ask your supplier whether they sell partial yards. Some will; others round up to the nearest half or full yard. When in doubt, rounding up is safer than falling short mid-project.

Area, depth, and cost planning

Many real projects start with a known square footage rather than separate length and width. A contractor may already know the driveway area, a landscaper may have measured a bed footprint, or a homeowner may be working from a plan that lists square feet. In that case, the area plus depth workflow is faster: multiply square feet by depth in feet, divide by 27, then apply waste and supplier rounding.

Cost planning is a separate step from the raw cubic-yard formula. The calculator now lets you enter a price per cubic yard and any delivery or short-load fee, then applies that price to the rounded supplier order rather than the unrounded raw volume. That mirrors how many suppliers quote bulk gravel, mulch, topsoil, fill dirt, and ready-mix concrete.

This is useful when comparing bagged material with a bulk order. A bulk yardage result can look cheaper per unit, but delivery fees, short-load minimums, pickup limits, and local supplier increments can change the real purchase decision.

How many cubic feet are in a yard and other quick conversion checks

One cubic yard contains 27 cubic feet, so the fastest cubic feet to cubic yards conversion is simply to divide by 27. That is the same as asking how many cubic feet are in a yard or how many cubic feet are in one cubic yard: the answer is always 27 because a cubic yard is a 3-foot by 3-foot by 3-foot cube.

This matters because many people measure a project in feet and inches but order in yards. A concrete patio, gravel base, mulch bed, or soil fill layer is often measured on site in feet, then converted into cubic yards only at the ordering stage. Keeping both units visible makes it easier to audit the calculation and compare it with supplier quotes.

If you only know the flat footprint, use a square feet to cubic yards approach by adding the installation depth first. Area alone is not enough for a bulk-material order because the supplier needs a three-dimensional volume rather than a two-dimensional surface measurement.

Worked example: planning a concrete patio slab

Suppose you are pouring a concrete patio that measures 12 feet long by 10 feet wide with a standard 4-inch slab depth. First convert the depth: 4 inches ÷ 12 = 0.333 feet. Next calculate cubic feet: 12 × 10 × 0.333 = 40 cubic feet. Finally convert to cubic yards: 40 ÷ 27 = 1.48 cubic yards.

Standard concrete weighs approximately 150 pounds per cubic foot, so this 40-cubic-foot slab would weigh roughly 6,000 pounds or about 3 tons. The calculator also estimates that this project would require roughly 14 wheelbarrow loads (at 3 cubic feet per load) and would fit within a single standard dump truck trip.

Adding 10 percent for waste and overfill brings the order to about 1.63 cubic yards. Most ready-mix suppliers would round this to 1.75 or 2 cubic yards to ensure full coverage.

Concrete yardage, gravel loads, mulch coverage, and soil fill

A general cubic yard calculator becomes much more useful when it helps you translate the same raw volume into the way the material is actually bought. Concrete projects often care about concrete yardage, rounded ready-mix order size, and whether the pour is still small enough for bagged mix. Gravel jobs often care about both cubic yards and tons because the same supplier may quote by either method. Mulch orders tend to care about coverage at a chosen depth and the comparison between bulk delivery and standard bag sizes. Topsoil and fill dirt projects often care about yardage plus the way the material settles after watering and grading.

That is why it helps to treat material type as more than a label. A gravel calculator yards workflow may use a higher waste allowance because of compaction. A mulch calculator may care more about square-foot coverage per cubic yard at 2 or 3 inches deep. A soil yards calculator may need a deeper fill assumption than mulch or gravel because raised beds and low spots commonly use thicker layers. The underlying volume formula is the same, but the ordering decision is different.

Concrete also introduces the common bag-count question. Because an 80 lb bag of concrete mix typically yields about 0.6 cubic feet, one full cubic yard is roughly 45 bags before any waste allowance is added. That makes bag counts useful for small repairs and posts, but once the order approaches a full yard, many users are better served by comparing the rounded yardage estimate with ready-mix minimums.

Common material weights and coverage

Different bulk materials vary widely in density, which affects both the weight per cubic yard and how the material is priced and delivered. Concrete typically weighs between 140 and 150 pounds per cubic foot (roughly 3,780 to 4,050 pounds per cubic yard). Gravel and crushed stone range from 90 to 110 pounds per cubic foot depending on the type, while topsoil averages 75 to 100 pounds per cubic foot and mulch is much lighter at 20 to 30 pounds per cubic foot.

Coverage area depends on the depth of application. One cubic yard of mulch covers approximately 324 square feet at 1 inch deep, 162 square feet at 2 inches deep, or 108 square feet at 3 inches deep. One cubic yard of gravel covers about 108 square feet at 3 inches deep, and one cubic yard of concrete covers approximately 81 square feet at a standard 4-inch slab depth.

A standard dump truck carries roughly 10 cubic yards per trip. A standard wheelbarrow holds about 3 cubic feet, so moving one cubic yard by wheelbarrow takes 9 loads. These practical estimates help you plan labour time and delivery logistics alongside your material volume.

How to round the result for ordering

A cubic yard estimate is rarely the final order number by itself. Concrete is often rounded to the nearest quarter yard or half yard after a waste buffer is applied. Gravel, topsoil, and mulch may be rounded to the nearest half yard or full yard depending on the supplier’s minimum sale size and delivery schedule.

A practical workflow is to calculate the raw cubic yards, apply a material-appropriate waste allowance, and then round the order to the supplier increment. That process is usually more reliable than trying to guess the final order without first checking the raw volume.

Limitations and scope

This calculator provides volume and weight estimates for rectangular project areas using standard conversion factors. It does not account for circular, triangular, or irregular shapes directly — for those, calculate the area in square feet separately and enter the result as a cubic feet value in direct-input mode.

The weight estimate depends on the material density value you enter. Real-world density varies by moisture content, compaction, aggregate size, and supplier. The default density of 100 lbs/cu ft is a general starting point — always confirm the actual density with your material supplier for accurate weight calculations.

Cubic yards are the primary bulk volume unit in the United States. In countries that use the metric system, bulk materials are typically sold by the cubic metre (1 cubic yard ≈ 0.7646 cubic metres). This tool reports results in US customary units.