Construction calculators, with the math shown.
Free construction calculators for roofing, masonry, framing, decking, fencing, and interior finishing, built for contractors and DIYers who need a number now. Enter your dimensions and the material estimate updates as you type.
27
Calculators
$0
Cost to use
Browser
Nothing to install
All calculators
One page per estimate, grouped by trade.
Roofing
Roof Pitch Calculator
Find your roof's angle, slope factor & percentage grade
Open calculatorRoofing Shingles Calculator
Squares and bundles of shingles needed for any roof
Open calculatorRoof Replacement Cost Calculator
What a new roof costs, by material and pitch
Open calculatorRafter Length Calculator
Rafter length from building width, pitch & overhang
Open calculatorMasonry & Landscaping
Concrete Calculator
Cubic yards and bag counts for any slab or footing
Open calculatorConcrete Slab Cost Calculator
What a concrete slab or driveway costs, installed
Open calculatorConcrete Driveway Cost Calculator
Concrete, asphalt and gravel priced side by side
Open calculatorGravel Calculator
Tons and cubic yards of gravel for any area
Open calculatorSand Calculator
Tons, cubic yards and bags of sand for pavers, pools and sandboxes
Open calculatorMulch Calculator
Cubic yards and bags of mulch for your beds
Open calculatorTopsoil Calculator
Cubic yards, tons, and bags of topsoil for any area
Open calculatorSod Calculator
Square feet, pieces, pallets and cost of sod for any lawn
Open calculatorCubic Yard Calculator
Cubic yards, cubic feet, tons and bags for any fill
Open calculatorConcrete Block Calculator (Cinder Block, CMU)
Blocks, mortar, sand and grout for a CMU wall
Open calculatorRetaining Wall Calculator
Blocks, rows, and cap units for your wall build
Open calculatorAsphalt & Bitumen Calculator
Tons, yards and material cost of hot mix asphalt
Open calculatorRebar Calculator
Grid spacing, linear feet & sticks for a slab
Open calculatorDecking & Fencing
Interior
Paint Calculator
How many gallons of paint the room actually takes
Open calculatorFlooring Calculator
Square footage and boxes, with waste factored in
Open calculatorInsulation Calculator
Rolls or batts needed for any wall or ceiling area
Open calculatorBlown-In Insulation Calculator
Bags needed for attic cellulose or fiberglass insulation
Open calculatorBaseboard Calculator
Linear feet and pieces of trim for any room
Open calculatorHow it works
Three steps from your measurements to a materials list you can order from.
Pick a calculator
Roofing, masonry, framing, decking, fencing, or interior finishing.
Enter your measurements
Use the dimensions you already have: length, width and depth, or rise and run.
Read the results
Material quantities and costs update as you type.
The formulas are the standard ones used in the trades. The calculators do the same arithmetic you would do with a calculator app and a notepad, as you type.
For contractors, estimators and DIY builders
Getting a material quantity wrong costs money in both directions. Over-order and you have paid for a pile of leftovers. Under-order and the job stops while you drive back to the supplier. Each calculator handles one estimate, which is faster than a spreadsheet and harder to get wrong than doing it in your head.
Standard trade math
Cubic feet to cubic yards on a concrete pour, slope factors on a roof, board feet on a lumber order. These are the formulas already in use, applied the same way on every page.
Waste allowances included
Estimates include cutting losses of 5% to 15%, depending on the material and the layout. A herringbone floor wastes far more than a straight one, and the numbers here account for that.
Frequently asked questions
Yes. You don't need an account or an email address. Open a page and start typing. There is no paid tier, so every feature is available to everyone.
The arithmetic is exact, and the formulas are the standard ones used in the trades. The math cannot account for waste, site conditions or how a particular brand behaves, so results are rounded and the calculators suggest adding 5 to 10% to material orders. Treat the result as an estimate, not a final number.
No. The calculators run in your web browser as you type, so there is nothing to download and no plugin or spreadsheet to keep.
Yes. The calculators are laid out to work one-handed on a phone, since the other hand is often holding a tape measure.