Construction Material Calculators
Find out exactly how much concrete, gravel, mulch, topsoil, sand, or sod you need — instantly and for free.
Ordering the wrong amount of concrete or gravel is one of the most common (and expensive) mistakes on DIY projects. Too little means a second delivery and a cold joint; too much means wasted money and a disposal problem. These calculators give you the exact cubic yards, cubic feet, and — where relevant — tons or bag counts for your project dimensions, with a built-in waste buffer option so you order right the first time.
Every calculator on this site works the same way: enter your dimensions, pick your unit of measure, and get instant results. No account required, no upsells — just the numbers you need before you call the supply yard or head to the hardware store.
Concrete Calculator
Cubic yards + bag count for slabs, footings, and more.
Gravel Calculator
Cubic yards and tons for driveways, paths, and drainage.
Mulch Calculator
Cubic yards plus 2 ft³ and 3 ft³ bag counts.
Topsoil Calculator
Cubic yards with settling allowance built in.
Sand Calculator
Cubic yards and tons for leveling and fill.
Sod Calculator
Rolls and pallets for any lawn area.
Frequently Asked Questions
- How many bags of concrete do I need for a 10×10 slab at 4 inches thick?
- A 10×10 slab at 4 inches (0.333 ft) thick is 33.3 cubic feet, or about 1.23 cubic yards. You would need 74 bags of 60 lb concrete mix or 56 bags of 80 lb mix. At this volume, ready-mix delivery is worth getting quotes on.
- How do I convert cubic feet to cubic yards?
- Divide cubic feet by 27. There are 27 cubic feet in one cubic yard (3 ft × 3 ft × 3 ft = 27 ft³).
- How much does a cubic yard of concrete weigh?
- A cubic yard of concrete weighs approximately 3,900–4,050 pounds (about 2 tons) when wet.
- When should I use ready-mix instead of bags?
- Ready-mix concrete becomes more economical at volumes above 1 cubic yard (roughly 27 bags). For larger pours, always get ready-mix quotes.
- Why should I add a waste buffer?
- Adding 5–10% extra accounts for spillage, uneven subgrades, and forms that aren't perfectly square. It's much cheaper to have a little left over than to run short mid-pour.
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