Buy the right amount.
Yards, bags, and gallons with waste baked in — so you are not back at the store mid-pour with wet gloves.
Runs in your browser · No signup · Estimate only — not a contractor bid
+10% so you don't come up short
Estimate only — not a contractor bid. Confirm bag yields and local codes before you pour or order.
Popular tools
Waste is a slider
Every pour spills, over-digs, and settles. Nudge the tape-measure slider from 0 to 25% and watch the yards and bag count move with it — no guessing, no scribbled margins on the back of a receipt.
Store units
Results come out the way the aisle sells them: cubic yards for the ready-mix truck, 40 / 60 / 80 lb bags for the pallet. Copy the list and hand it to the counter.
Same site clusters
Concrete, gravel, mulch, paint, and roof pitch all live under one roof so a weekend project that needs three materials does not need three tabs.
Material counts before the cart
Most “how much do I need” pages spit out one number and call it done. On a real Saturday you care about three things that rarely show up together: volume after waste, which bag size the aisle actually stocks, and whether bulk yards beat stacking sixty bags in a hatchback.
A 10×10 pad at four inches looks like “about a yard” until you do the thickness math — then you are staring at 1.2 yd³ before anyone spills a wheelbarrow. Add ten percent for over-dig and you are shopping, not guessing.
HomeMaterialBase is a set of free browser calculators for homeowners and DIY jobs. Concrete comes back as cubic yards and 40 / 60 / 80 lb bag counts. Gravel and topsoil talk in yards (and tons when that is how the yard sells it). Mulch can show bags. Paint rounds gallons after doors and windows come out. Roof pitch is rise over run — useful before you argue with a shingle estimate, not a roofing quote.
Math runs locally in your browser. No signup. Every result is a planning estimate — something to take to the counter — not a stamped takeoff and not a contractor bid.
Start with the pour or the bed
Pouring this weekend? Open the concrete calculator for slabs, pads, footings, and post holes. If you already know it is a rectangle, the slab calculator is tighter. If a truck quote already gave you yards and you only need bag math, use the bag calculator.
Filling a driveway base or a flower bed? Gravel, mulch, and topsoil all take area and depth. Painting a room? The paint calculator subtracts openings before it rounds gallons. Checking how steep a roof is before you order? Roof pitch.
What these numbers are — and are not
They are shopping numbers. Bag yields vary by brand; a high-early mix may not match the 0.60 cu ft rule of thumb for an 80 lb bag. Paint coverage on the can beats any website default. Gravel density depends on rock type and how wet the pile is when it leaves the yard.
They are not structural design, mix design, PSI, rebar schedules, or labor pricing. If a footing carries a house, confirm dimensions with someone who stamps drawings. If a contractor already bid the job, use their takeoff — this site will not argue with a signed quote.
FAQ
A free set of material-quantity calculators in the browser — how much to buy, with waste and common bag sizes. It is for a store run, not a contractor quote.