Free building and materials calculators for home and DIY projects
Work out how much material a job needs. Each calculator shows its formula, a worked example, the assumptions it makes and the sources behind them.
- Instant answer as you type
- Nothing you type is sent anywhere
- Worked example with clear steps
Calculators
Concrete
Slabs, footings, bags and rebar.
Concrete Yards Calculator
Cubic yards, cubic feet and weight of concrete for a slab, pad or footing.
Concrete Bag Calculator
How many 40, 50, 60 or 80 lb bags of concrete a slab or pad needs.
Fence Post Concrete Calculator
Bags of concrete for each fence post and for the whole fence.
Concrete Tube Form Calculator
Cubic feet, yards, bags and weight of concrete for a round tube form, pier or column.
Concrete Block Calculator
How many concrete blocks a wall needs, with optional core fill and weight.
Rebar Calculator
Length and weight of rebar for a slab, from its size, bar size and spacing.
Concrete Steps Calculator
Cubic feet, yards and weight of concrete for solid concrete steps, with an optional landing.
Brick Calculator
Bricks for a wall, from its area, less the openings, with an extra for breakage.
Concrete Calculator
Cubic yards, bags and weight of concrete for a slab or a footing, and a guide to every concrete page.
Landscaping
Gravel, asphalt, mulch, soil and sod for yards and paths.
Gravel Calculator
How many cubic yards and tons of gravel a driveway, path or bed needs.
Asphalt Calculator
Tons of asphalt and square yards of paving for a driveway, lot or path.
Sod Calculator
Square feet and pallets of sod for a lawn, with extra for cuts and waste.
Mulch Calculator
Cubic yards and bags of mulch for a bed, from its size and the depth you want.
Topsoil Calculator
Cubic yards and tons of topsoil for a bed or lawn, from its size and depth.
Roofing
Pitch, shingles and metal panels.
Roof Pitch Calculator
Pitch, angle, slope percent, multiplier and rafter length for a roof.
Roofing Calculator
Roof area, squares and shingle bundles from the building size and pitch.
Metal Roofing Calculator
How many metal roofing panels a roof plane needs, from your panel's coverage width and length.
Fencing and decks
Posts, boards, stairs and fence runs.
Stair Calculator
Steps, riser height, run and stringer length for the rise between two floors.
Deck Calculator
Deck boards, joists and screws from the deck size and board width.
Fence Calculator
Posts, rails and pickets for a fence from its length and post spacing.
Chain Link Fence Calculator
Posts, ties, rolls and top rails for a chain link fence.
Interior
Paint, tile, flooring, drywall and insulation.
Tile Calculator
Tiles and boxes for a floor, wall, shower or backsplash, from its area and the tile size.
Drywall Calculator
Sheets of drywall for the walls and ceiling of a room, less the openings.
Insulation Calculator
Rolls or bags of insulation and the depth for an R-value, for an attic or wall.
Flooring Calculator
Boxes of laminate, vinyl plank or wood flooring for a room, with an extra for cuts.
Paint Calculator
Gallons of paint for the walls and ceiling of a room, from its size, the coats and the coverage.
Area and units
Square footage and unit conversions.
Room Square Footage Calculator
Square feet, yards and meters of a room from its length and width in feet and inches.
Acres to Square Feet Calculator
Convert acres to square feet and square feet to acres, with square yards and a table.
Square Footage Calculator
Square feet, yards, acres and meters of a rectangle, circle or triangle, and a guide to every area page.
What you get
Instant answer as you type
The result updates as you type, with no button to press.
Nothing you type is sent anywhere
The calculators run in your browser. There are no accounts, no forms and no cookies.
Worked example with clear steps
Each calculator has a worked example and numbered steps for using it.