Construction & DIY calculators
Work out how much concrete, lumber, or material a project needs — in the units suppliers actually sell: cubic yards, board feet, and bags.
All material calculators
Concrete volume · slab and yard costs · footings and rebar · lumber and hardwood
Concrete Calculator
Slabs, footings, and round columns into cubic yards, cubic meters, 60 lb and 80 lb bags, with cost.
LumberBoard Foot Calculator
Price hardwood by volume: board feet from thickness, width, and length, then cost per board foot.
GuideHow many bags of concrete in a yard?
Bag counts for 40, 50, 60, and 80 lb mixes, with a calculator and cost comparison.
PaintPaint Calculator
Gallons per coat for walls and ceiling from room dimensions, with coverage adjusted for texture and bare drywall.
TileTile Calculator
Tiles and boxes from your area, with the grout joint and a waste allowance that matches the layout.
DrywallDrywall Calculator
Sheets, joint compound, tape and screws from room dimensions, for 4 by 8 or 4 by 12 board.
GravelGravel Calculator
Cubic yards and tons of crushed stone or pea gravel, with the compaction allowance most calculators skip.
SoilTopsoil Calculator
Yards, bags and tons of topsoil, compost or mulch, including the settle allowance for a new bed.
DeckDeck Calculator
Decking boards counted by row, plus joists, posts and the concrete their footings need.
FenceFence Calculator
Posts, pickets, rails and bags of concrete for a run, with the extra posts a gate requires.
RoofingRoofing Calculator
Squares and shingle bundles from the footprint and pitch, using the slope factor for every common roof.
GuideConcrete slab cost
2026 material and labor prices per square foot at 4, 5, and 6 inches, plus a cost calculator.
GuideNominal vs actual lumber sizes
Why a 2×4 measures 1½ × 3½ inches, the full chart, and a size converter.
ConcreteFooting Calculator
Strip and pad footings in cubic yards and bags, with typical sizes and frost-depth guidance.
RebarRebar Calculator
Grid lines, linear feet, 20 ft bars, weight, and cost for a slab mat at any spacing.
GuideConcrete weight per yard
Pounds, tons, and kilograms per yard, slab dead loads, and what a truck can actually carry.
GuideHardwood prices by species
Board-foot prices for oak, maple, walnut, cherry, and more, with grade and thickness multipliers.
RebarRebar spacing chart
Bar size and spacing by application, ACI maximums, and a quick bar count.
CostConcrete cost by state
Ready-mix price ranges by region, plus an installed cost estimate for your slab.
GuideHow much does a yard cover?
Square feet per cubic yard at every thickness, with bag equivalents.
CostConcrete cost per yard
Ready-mix versus bags, with the fee structure that changes the real price.
GuideBag of concrete coverage
Square feet per 40, 50, 60, and 80 lb bag at every thickness.
LumberBoard foot chart
Board feet for common sizes at 6, 8, 10, 12, and 16 feet, with prices.
GuideWhat PSI concrete do I need
Strength by application, and why stronger mixes crack more.
GuideRebar in a 4 inch slab
When a slab needs steel and when it does not, with spacing and cover.
GuideCuring time for concrete
Walking, driving and sealing times, and why curing is not drying.
GuideControl joint spacing
Spacing, depth and cut timing by slab thickness, with layout rules.
How these calculators think
Construction math fails in two places: unit conversion and waste. A slab measured in feet with a thickness in inches has to be converted before multiplying, and every formula on this site shows that step instead of hiding it. The calculators also keep your waste allowance as a separate, visible percentage, so a 10% overage is a number you chose rather than a fudge factor baked into the result.
Buying in the right unit
| Material | Suppliers sell by | What the calculator shows |
|---|---|---|
| Ready-mix concrete | Cubic yard (27 cu ft) | Cubic yards, rounded up to the next ¼ yard |
| Bagged concrete | 60 lb or 80 lb bag | Bag counts at both sizes, rounded up |
| Hardwood lumber | Board foot (144 cu in) | Board feet per piece and total, plus cost |
| Framing lumber | Piece or linear foot | Linear feet and board-foot equivalent |
What's in this section
- Calculators: concrete volume and bags, board feet and lumber cost, strip and pad footings, rebar grids.
- Guides with numbers: bags per cubic yard, slab cost per square foot, concrete weight per yard, nominal vs actual lumber sizes, hardwood prices by species.
- Data you can check: bag yields, dead loads, bar weights, and price ranges are all cited to a manufacturer figure, code provision, or trade association.
Frequently asked questions
Do these calculators include waste?
The concrete calculator has a visible waste field (10% by default). The board foot calculator does not add waste automatically — add 15% for straightforward projects and 25% when you need matched grain.
Why do my numbers differ from the lumber yard's?
Suppliers often round thickness and width up to the next inch when pricing hardwood. If your yard does that, enter the rounded dimensions to match the invoice.
Can I use these for a bid?
Yes, as a starting point. Add your own labor, delivery, and contingency lines, and confirm quantities against the plan and the supplier's yield figures.