How much material do you need? Calculate it free.

BuildCalc turns your project's dimensions into exact quantities — cubic yards, tons, bags, boxes and total cost — for mulch, gravel, concrete, asphalt and more. Imperial and metric, no sign-up.

Built for DIY & contractors: Real formulas, cited sources, imperial + metric — always free.

Calculators

Pick a material to get started

Enter your area and depth (or room size) and get the quantity, bags or tons, and an optional cost estimate in seconds.

Mulch Calculator

Cubic yards and bags by bed area and depth.

Topsoil Calculator

Yards, tons and bags for lawns and raised beds.

Sand Calculator

Leveling-sand volume, weight and bags by area.

Gravel Calculator

Cubic yards and tons for paths and driveways.

Concrete Calculator

Cubic yards and 60/80 lb bags for slabs.

Asphalt Calculator

Hot-mix tonnage for driveways and overlays.

Paver Calculator

Number of pavers by area, size and waste.

Flooring Calculator

Boxes needed by room area plus a waste margin.

Get your estimate in three steps

Step 1: Measure your area

Enter length and width (or the total square footage). Round, triangular and bordered shapes are supported where it matters.

Step 2: Set depth or thickness

Use the recommended default for your project — 3 in for mulch, 4 in for a concrete slab, 2 in for a gravel path — or enter your own.

Step 3: Read your quantity

Get cubic yards, tons, bags or boxes instantly — plus total cost if you add your local price per unit.

Done!

Why BuildCalc

Why estimate with BuildCalc

Estimates you can take to the supplier — and an honest note when a number is a range, not a fact.

Imperial and metric

Square feet, cubic yards and US tons by default, with a one-tap switch to m², m³, litres and tonnes.

Formulas with sources

Material densities and coverage rates are calibrated against published references and shown on every page, so you can check our math.

Free, no account

Every calculator is free and runs entirely in your browser. We never ask you to sign up or store the numbers you enter.

Quantities, bags and cost

Beyond raw volume, we convert to the bags, boxes or tons you actually buy — and multiply by your price for a total.

FAQs

Building material calculator FAQs

How much area does a cubic yard cover?

One cubic yard spread 1 inch thick covers about 324 square feet. At a typical 3-inch mulch depth that drops to roughly 108 sq ft, and at a 2-inch gravel depth about 162 sq ft.

How many bags do I need?

It depends on the bag size. Mulch usually comes in 2 cu ft bags (about 13.5 bags per cubic yard), while an 80 lb bag of concrete mix yields roughly 0.6 cu ft, so it takes about 45 bags to make one cubic yard.

Should I add extra for waste?

Yes — for flooring and pavers we add a waste margin (about 10% for straight layouts, 15–20% for diagonal or herringbone patterns) so cutting and breakage do not leave you short.

How accurate are the estimates?

The geometry is exact, but bulk materials vary with moisture and gradation, so densities are typical mid-range values. We show the range on each page — order a little extra for full coverage.

Do you store the measurements I enter?

No. The calculators run in your browser and your inputs are never sent to or stored by us. See our Privacy Policy for details.

Can I use these for a contractor quote?

They are great for budgeting and ordering materials. For load-bearing or structural work, confirm depths and quantities against your local building code and your supplier.

Start your estimate

Pick your material, enter your measurements, and get the exact quantity to order — in seconds, for free.