Cubic Yard Calculator Blog

Why These Guides Exist

Ordering bulk material is one of those jobs that looks simple until the truck arrives. Order too little and you pay a second delivery fee for half a yard. Order too much and you spend a weekend finding places to hide a pile of soil. Nearly every one of those mistakes comes down to a measurement taken in the wrong unit or a step skipped in the arithmetic.

This blog collects the methods we use ourselves. Each article sticks to one job, shows the numbers in full and points out where people usually go wrong. If you are new to volume calculations, start with the cubic yard calculation guide. If you already know the basics and just want an answer, the cubic yard calculator on our home page does the math for any shape.

How to Calculate Cubic Yards in Four Steps

Every material on this site, from bark mulch to ready mix concrete, is worked out the same way. The only thing that changes is the depth you spread it and how much extra you allow for.

1. Measure the length and width of the area in feet. Round awkward edges out rather than in.
2. Measure the depth you want and convert it to feet by dividing inches by 12.
3. Multiply length × width × depth to get cubic feet.
4. Divide the cubic feet by 27 to get cubic yards.

Here is how that looks for a garden path 30 ft long and 3 ft wide, covered 2 inches deep. The area is 90 square feet. Two inches is 0.167 ft, so the volume is about 15 cubic feet, which works out to 0.56 cubic yards. The full cubic yard guide adds a faster shortcut, metric units and more worked examples.

Depth in inches, converted to feet

The conversion step is where most errors creep in, so it helps to keep the common depths handy.

Cubic Yard Formulas for Different Shapes

Most beds and slabs are rectangles, but plenty are not. These cubic yard formulas cover the shapes that come up most often. Measure in feet and the result is in cubic yards.

A long planter that needs exactly one yard

A planter 12 ft long and 3 ft wide, filled 9 inches deep, holds 12 × 3 × 0.75 = 27 cubic feet. That is one cubic yard on the nose, which makes it a handy mental reference when you are sizing up other spaces.

A wide ring around a mature tree

Say the ring is 10 ft across and you leave a 2 ft circle clear around the trunk. The outer radius is 5 ft and the inner radius is 1 ft, so the area is 3.1416 × (25 − 1), about 75.4 square feet. At 3 inches deep that is roughly 18.9 cubic feet, or 0.70 cubic yards.

A triangular corner bed

A corner bed with two straight sides of 8 ft has an area of 8 × 8 ÷ 2, which is 32 square feet. Spread 3 inches deep, it needs 8 cubic feet of material, about 0.3 cubic yards. For L shapes and odd outlines, split the space into these simple pieces and add them up, or let the Square Feet Calculator handle the area for you.

Cubic Yard Conversion Guides

Bags are labeled in cubic feet, delivery tickets in cubic yards and some quarries quote in tons. Five of our guides deal with these switches in detail.

How many cubic feet are in a cubic yard covers the 27 to 1 relationship in both directions, with truck beds and a mental trick for dividing by 27, while how many bags are in a cubic yard turns any bag label into a count per yard. Cubic yards to tons explains how density links volume and weight, with typical figures for mulch, soil, sand, gravel and concrete and a method for comparing quotes priced in different units. If you are starting from an area on a plan or survey, square feet to cubic yards shows the conversion with a divisor table for common depths, and how much area one cubic yard covers works it in reverse, from a delivered yard to the ground it will spread over. For metric projects, one cubic meter is about 1.31 cubic yards.

Landscaping Calculator Guides by Material

The formula stays the same, but each material behaves differently once it is on the ground. Here is what sets each one apart, along with where to read more.

Mulch calculator guide

Mulch is light and forgiving, and the most common job is not a new bed but topping up an old one. Adding 1 inch over 400 square feet of existing beds takes about 1.23 cubic yards. Our article on how much mulch you need works through a whole front garden and the bags versus bulk decision, and the Mulch Calculator gives both figures at once.

Topsoil calculator guide

Topsoil jobs range from a quarter inch sprinkled over a lawn to a foot or more in a raised bed, so the depth decision matters more than with any other material. Our guide to how much topsoil you need covers lawns, vegetable gardens, raised beds and leveling, and the Topsoil Calculator shows cubic yards and estimated tons.

Gravel calculator guide

Gravel is where layers and compaction come into play. A driveway might need two different stones, each calculated separately. Our guide to how much gravel you need walks through a layered driveway from measurement to tons, the Gravel Calculator lets you set the density to match your supplier, and our guide to how much sand you need covers the bedding layer under pavers.

Concrete calculation guide

Concrete leaves the least room for error because you cannot top it up next week. Round footings are a good example. A 12 inch tube form set 4 ft deep holds about 3.14 cubic feet. At roughly 0.6 cubic feet per 80 lb bag, that is 6 bags once you round up. Our slab estimating walkthrough covers patios and pads, how much concrete you need covers post holes, steps and walls, and the Concrete Calculator converts yards into 40, 60 and 80 lb bags.

How We Check the Numbers in These Guides

Every worked example on this blog is recalculated before it goes live, and the totals are checked against our own calculators so the articles and the tools agree. Where a figure depends on the material, such as density, compaction or bag yield, we give a typical range rather than a single number and say so clearly.

We do not sell materials, so there is no reason for us to push you toward a bigger order. The calculators never add a waste allowance unless you ask for one. If you spot a number that looks wrong, tell us and we will correct it.

Which Guide Should You Read First?

If you have never worked out a volume by hand, start with the step by step cubic yard guide. It explains the formula and the shortcut and gives you the foundation every other article builds on.

If you already have a project in mind, go straight to the matching article: mulch for garden beds, topsoil for lawns and raised beds, gravel for paths and driveways, or concrete for slabs and pads. Then run your figures through the matching calculator before you call the supplier. We add new guides as readers send in questions, so if something is missing, let us know.

Frequently Asked Questions