SamCalculator

Cubic Yard Calculator

Calculate cubic yards, estimate material quantities, convert units, and determine how much concrete, gravel, mulch, sand, topsoil, or fill dirt your project needs.

Project dimensions

Quick start:

Area shape

Depth / thickness

≈ 4.0 in

Material

Fill in the dimensions above and press Calculate to reveal your cubic yards, material weight, bag counts, unit conversions, and smart insights.

What is a cubic yard?

A cubic yard calculator turns a few simple measurements — length, width, and depth — into the exact amount of material your project needs. A cubic yard is a cube one yard (three feet) on every side, equal to 27 cubic feet, and it's the standard unit suppliers use to sell and deliver concrete, gravel, mulch, sand, topsoil, fill dirt, and compost in bulk. Instead of guessing and ending up with a half-finished slab or a leftover mountain of stone, you get the precise volume in cubic yards, cubic feet, and cubic metres in one step.

This tool goes well beyond a basic length × width × depth box. It handles rectangular, circular, and triangular areas as well as direct cubic-foot or cubic-metre entry, includes a built-in density database for eight common materials so it can estimate weight and bag counts, applies a waste allowance, rounds up to your supplier's order increment, and prices the whole project in your currency. Whether you're pouring a patio, topping a driveway, filling a raised bed, or surfacing a playground, the goal is the same: order the right amount the first time, avoid a costly second delivery, and never pay for material you don't use.

How to calculate cubic yards

Measure length, width, and depth

Measure the area you want to fill and how deep the material should sit. Use the same unit, or let the calculator convert feet, inches, yards, metres, and centimetres for you. For a rectangle, that's length × width × depth; for a circle use π × radius² × depth; for a triangle use ½ × base × height × depth.

Convert the volume to cubic yards

Multiply the dimensions to get the volume in cubic feet, then divide by 27 to get cubic yards — because a cubic yard is 3 ft × 3 ft × 3 ft = 27 cubic feet. If you measured in inches or centimetres, convert to feet first so the units line up before dividing.

Estimate weight and material

Material is often sold by weight as well as volume, so the calculator multiplies the volume by the material's bulk density. A cubic yard of gravel weighs roughly 1.4 tons while a cubic yard of mulch weighs under half a ton — so weight and volume never line up one-to-one between materials.

Add waste and round up to order

Material is lost to spillage, settling, and uneven ground, and concrete can't be topped up once it cures. A 5–10% waste allowance suits most jobs. The calculator then rounds the total up to your supplier's increment — 0.25, 0.5, or 1 cubic yard — so the quantity you order is the quantity you can actually buy.

3 ways to use this calculator

1

Order the exact amount

Enter your area and depth to get the precise cubic yards, cubic feet, and cubic metres, with a waste allowance and supplier rounding built in so you never run short or massively over-order.

2

Estimate weight and bags

Pick a material and the calculator returns the delivery weight in tons and the number of bags — 40/60/80 lb concrete bags, 2 ft³ landscape bags, or 1 yd³ bulk bags — plus the truckloads needed.

3

Budget the project

Add a price per cubic yard, cubic metre, or cubic foot and instantly see your material cost, the cost of the waste allowance, and the total spend for the recommended order in your currency.

Material ordering best practices

  • Always measure depth carefully — it multiplies straight into the volume and is the single biggest driver of how much material you buy.
  • Add a waste allowance: 5–10% for most fill and landscaping jobs, and 10% for concrete so a short pour never stalls the work.
  • Round up to your supplier's order increment — ready-mix concrete usually sells in 0.25 yd³ steps, and bulk material by the half or full yard.
  • Split irregular areas into rectangles, circles, and triangles, calculate each separately, and add the cubic yards together.
  • Order loose by the cubic yard or truckload for large jobs — bulk delivery is far cheaper per yard than bagged material once you pass roughly 1–2 cubic yards.

Why getting the quantity right matters

Getting the quantity right is one of the few places in a project where a small measuring error costs real money twice over. Order too little and the job stalls while you wait for a second delivery — and a small top-up load carries the same delivery fee as a full one. Order far too much and you've paid to have material dumped that you now have to spread, store, or haul away. With concrete the stakes are higher still: a cold joint where fresh concrete meets a slab that has already begun to cure creates a permanent weak line, so running short mid-pour is something to avoid at all costs.

An accurate cubic-yard figure, converted to weight and truckloads with a sensible waste margin, is the best way to keep a project on time and on budget. Beyond the headline volume, the details decide the final bill: depth drives cost more than area, each material's density changes how much weight (and how many truckloads) a given volume becomes, and the unit your supplier prices in — per cubic yard, per ton, or per bag — determines how their quote maps to your site. Working all of that out in one place is what separates a confident order from an expensive guess.

Real-life material projects

Concrete patio (20 × 15 × 4 in)

A 300 ft² patio at 4 in thick is 100 ft³ — about 3.7 cubic yards of concrete. Add 10% and order 4.25 yd³ of ready-mix so the pour finishes in one continuous placement.

Garden mulch (30 × 10 × 3 in)

A 300 ft² bed at 3 in deep is 75 ft³ — about 2.8 cubic yards of mulch, or roughly 38 of the standard 2 ft³ bags. Loose by the yard is far cheaper at this size.

Gravel driveway (40 × 12 × 6 in)

A 480 ft² driveway at 6 in deep is 240 ft³ — about 8.9 cubic yards of gravel. With a 10% compaction allowance, order roughly 10 yd³ to reach the finished depth.

Topsoil for a lawn (50 × 25 × 2 in)

A 1,250 ft² lawn at 2 in deep is about 208 ft³ — roughly 7.7 cubic yards of topsoil. Topsoil settles after watering, so ordering on the generous side keeps the grade level.

Raised beds and planters

Fill raised beds and planters with a topsoil-and-compost blend. Calculate each bed as a rectangle, add the cubic yards, and round up — soil settles and you'll want a little extra after the first watering.

Footings and foundations

Estimate concrete for strip footings, pad footings, and slab foundations by treating each section as a rectangle or column. Order ready-mix with a 10% allowance so the structural pour never runs short.

Core cubic yard formulas

Rectangular volume

Length × Width × Depth

A 20 ft × 15 ft area at 4 in (0.333 ft) deep is 100 ft³. All three measurements must be in feet before you multiply.

Cubic yards from cubic feet

Cubic Yards = Cubic Feet ÷ 27

100 ft³ ÷ 27 = 3.7 cubic yards. A cubic yard is 3 × 3 × 3 = 27 cubic feet, which is why 27 is the magic number.

Circular volume

π × radius² × Depth

A 10 ft diameter bed (5 ft radius) at 3 in deep is π × 25 × 0.25 ≈ 19.6 ft³, or about 0.73 cubic yards.

Triangular volume

½ × Base × Height × Depth

A triangular area with a 12 ft base and 8 ft height at 4 in deep is 0.5 × 12 × 8 × 0.333 ≈ 16 ft³ — about 0.59 cubic yards.

Weight

Cubic Metres × Density

A cubic yard (0.765 m³) of gravel at 1,680 kg/m³ weighs about 1,285 kg — roughly 1.4 US tons. Lighter materials like mulch weigh far less.

With waste

Volume × (1 + Waste %)

3.7 cubic yards with a 10% allowance is about 4.1 yd³, rounded up to 4.25 yd³ at a 0.25-yard order increment.

Common cubic yard calculation mistakes

1

Mixing up units

The most common error is multiplying feet by inches. A 4 in depth is 0.333 ft, not 4 — convert every dimension to the same unit before you multiply, or let the calculator's unit selectors handle it for you.

2

Forgetting to divide by 27

Length × width × depth in feet gives cubic feet, not cubic yards. Suppliers sell by the yard, so you must divide cubic feet by 27. Skipping this step makes the order look 27 times too large.

3

Ignoring waste and settling

Loose material compacts, soil settles after watering, and some is always spilled. Ordering the exact calculated volume leaves you short — add 5–10%, and round up to the supplier's increment.

4

Using one depth for the whole site

Driveways, slabs, and beds often need different depths in different zones. Measure each zone separately, calculate its cubic yards, and add them rather than averaging a single depth across the lot.

How accurate is this calculator?

Every figure here uses the standard geometry and density maths that contractors, landscapers, and material suppliers rely on: area multiplied by depth for volume, cubic feet divided by 27 for cubic yards, and volume multiplied by each material's bulk density for weight, with a transparent waste allowance you control. The density values are published loose, dry bulk densities for each material, and the truckload counts assume a typical dump-truck capacity you can adjust to your supplier's trucks.

Treat the results as an accurate planning estimate, not a substitute for a supplier quote. Material quantities are estimates based on the dimensions, density assumptions, and waste percentage you enter — actual requirements vary with compaction, moisture content, supplier specifications, and site conditions. For large or structural jobs, especially concrete, confirm the final order against your supplier's pricing and your own site measurements before booking the delivery.

Frequently Asked Questions

A cubic yard is a unit of volume equal to a cube that is one yard (three feet) long on every side. Because each side is 3 feet, a cubic yard contains 3 × 3 × 3 = 27 cubic feet, or about 0.765 cubic metres. It's the standard unit used to sell and deliver bulk materials like concrete, gravel, mulch, sand, topsoil, and fill dirt in the United States, so most suppliers quote prices and truckloads by the cubic yard.

Measure the length, width, and depth of the area in the same unit, multiply them together to get the volume, then convert to cubic yards. The simplest method is to convert all three measurements to feet, multiply them to get cubic feet, and divide by 27. For example, a 20 ft × 15 ft area that is 4 inches (0.333 ft) deep is 20 × 15 × 0.333 = 100 cubic feet, and 100 ÷ 27 ≈ 3.7 cubic yards. This calculator does the unit conversion and the division for you.

You divide by 27 because there are 27 cubic feet in one cubic yard. A yard is 3 feet, and volume scales with the cube of length, so a cube that is 3 feet on each side holds 3 × 3 × 3 = 27 cubic feet. When you measure length, width, and depth in feet and multiply them, the answer is in cubic feet — dividing by 27 converts that into cubic yards, the unit suppliers actually sell by.

There are exactly 27 cubic feet in one cubic yard. This comes from 3 feet per yard cubed: 3 × 3 × 3 = 27. So 2 cubic yards is 54 cubic feet, 5 cubic yards is 135 cubic feet, and so on. To go the other way, divide cubic feet by 27 to get cubic yards.

One cubic yard of mulch (27 cubic feet) covers about 324 square feet at 1 inch deep, 162 square feet at 2 inches, 108 square feet at 3 inches, and 81 square feet at 4 inches. Most flower beds use a 2–3 inch layer, so a single cubic yard typically covers roughly 100–160 square feet. Deeper layers cover proportionally less area, which is why depth matters so much when ordering.

It depends on the bag size. Since a cubic yard is 27 cubic feet, you need about 14 of the standard 2-cubic-foot landscape bags, 18 of the 1.5-cubic-foot bags, or 27 of the 1-cubic-foot bags to equal one cubic yard. For concrete, one cubic yard takes roughly 45 of the 80 lb premix bags, 60 of the 60 lb bags, or 90 of the 40 lb bags — which is why anything over about a cubic yard is far cheaper ordered loose or as ready-mix.

Yes. Material is always lost to spillage, settling, compaction, and uneven ground, so ordering the exact calculated volume usually leaves you short. A 5–10% waste allowance suits most landscaping and fill jobs, and around 10% is standard for concrete because a pour can't be topped up once it starts to cure. After adding the allowance, round up to your supplier's order increment — often 0.25 cubic yard for ready-mix and 0.5 or 1 cubic yard for bulk material.

Calculate the slab or footing volume in cubic feet (length × width × thickness, all in feet) and divide by 27. For a 20 ft × 15 ft slab that is 4 inches (0.333 ft) thick, that's 100 cubic feet ÷ 27 ≈ 3.7 cubic yards. Add about 10% for waste and a short pour, then round up to the nearest 0.25 yard, giving roughly 4.25 cubic yards to order. Always confirm with your ready-mix supplier, who can advise on the right mix and minimum load.

Yes. You just have to convert inches to feet first, because mixing units gives the wrong answer. Divide any inch measurement by 12 to get feet — so 4 inches is 0.333 feet and 6 inches is 0.5 feet — then multiply length × width × depth in feet and divide by 27. This calculator lets you enter each dimension in inches, feet, yards, metres, or centimetres and handles the conversion automatically, so you never have to do it by hand.

It depends entirely on the material, because weight comes from volume multiplied by density. A cubic yard of concrete weighs about 3,700 lb (1.85 US tons), gravel about 2,800 lb (1.4 tons), sand about 2,700 lb, topsoil about 2,000–2,200 lb, and mulch only about 600–1,000 lb. This is why two materials of the same volume can need very different numbers of truckloads — the calculator estimates the weight for whichever material you select.

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