All Free Calculators

Every tool is free, needs no sign-up, and runs entirely in your browser. Results use real milled lumber dimensions and round up to units you can actually buy.

Material quantities

• Board foot calculatorLumber volume from thickness x width x length
• Deck boards calculatorBoard count and joist layout for a deck
• Plywood sheets calculatorSheet count for walls, floors or sheathing
• Wall studs calculatorStud count, corners and openings included
• Joist span calculatorCheck a span against the IRC table
• Deck cost calculatorMaterial cost from square feet and board price
• Hardwood flooring calculatorBoxes and board feet for a floor area
• Paint coverage calculatorGallons per coat for any room size
• Fence material calculatorPosts, rails, pickets and concrete bags
• Roof pitch calculatorRise and run to pitch, degrees and multiplier
• Rafter length calculatorCut length with overhang and birdsmouth
• Stair stringer calculatorRiser height, tread depth and stringer length
• Lumber waste calculatorNominal vs actual size: how many extra boards
• Full deck bundle calculatorFull deck material list in one pass
• Nominal vs actual calculatorWhat a 2x4 really measures
• BF → sq ft calculatorConvert between board feet and square feet
• Miter angle calculatorMiter and bevel for any corner angle
• Dowel spacing calculatorEven dowel layout across a panel
• Screw quantity calculatorScrews per board and boxes to buy
• Hardwood yield calculatorLumber recovered from a log after drying
• Firewood cords calculatorCords, cubic feet and burn time
• Dust collection calculatorCFM and duct velocity for your machines

Reading a result

Every result on this site follows the same three rules, and knowing them tells you how much margin the number already contains.

• Real milled dimensions, not nominal names. A 2x4 is entered and calculated as 1.5 by 3.5 inches. This is the single biggest difference between these calculators and the ones that multiply nominal figures.
• Rounded up to what you can buy. Sheet counts, box counts, bag counts and picket counts always round up to a whole purchasable unit. You cannot buy 6.2 sheets of plywood.
• Waste is added, then rounded. Where a waste factor applies, it is added before rounding so the allowance is not silently lost to the ceiling operation.

Which calculator to start with

For framing and sheathing, start with the board foot or plywood sheet calculator and work outward. For a deck, the project bundle covers decking, joists, beams, posts, concrete, screws and railing in one pass, which is faster than running four separate tools. For anything structural such as joists or stairs, run the span or stair calculator first: if the geometry does not pass, the material list is not worth building yet.

None of these tools replace a local building department. They give you numbers that match the material you will actually be sold, which is what most estimates get wrong.