22 free tools
DIY & Home calculators
Paint, flooring, tile, concrete, roofing, landscaping, AC and water heater sizing, wiring and insulation estimates. Each tool shows the formula, worked examples and sources.
DIY & HomeAC Tonnage CalculatorWhat size central air conditioner or heat pump (in tons and BTU/h) a house needs, from its square footage and ceiling height.DIY & HomeAttic Insulation CalculatorHow much blown-in attic insulation to add: the R-value to reach the ENERGY STAR level for your climate zone, the depth, volume and bags.DIY & HomeBoard Foot CalculatorBoard feet and cost of lumber from thickness, width, length and quantity, for hardwood or framing lumber.DIY & HomeBrick CalculatorNumber of bricks for a wall from its size, brick type and mortar joint, minus openings, with waste.DIY & HomeBTU CalculatorAir conditioner size in BTU/h for a room from its area, sun exposure, number of people and kitchen use.DIY & HomeCinder Block CalculatorNumber of concrete (cinder) blocks for a wall from its length and height, minus doors and windows, with courses and waste.DIY & HomeConcrete CalculatorCubic yards and bags of concrete (40, 50, 60 or 80 lb) for a slab, footing or round post holes and columns.DIY & HomeDrywall CalculatorSheets of drywall for a room's walls and ceiling in 4×8, 4×10 or 4×12 sizes, minus doors and windows.DIY & HomeFence CalculatorPosts, rails, pickets and bags of concrete for a wood fence from its length and post spacing.DIY & HomeFlooring CalculatorSquare feet, boxes and cost of laminate, vinyl plank, hardwood or carpet for a room, with waste allowance.DIY & HomeGravel CalculatorCubic yards and tons of gravel, crushed stone or sand for a driveway, path or base at any depth.DIY & HomeMulch CalculatorCubic yards and bags of mulch, topsoil or compost for a garden bed or tree ring at any depth.DIY & HomePaint CalculatorGallons (or litres) of paint for a room's walls and ceiling, minus doors and windows, for any number of coats.DIY & HomePaver CalculatorNumber of pavers for a patio or walkway, plus the gravel base and bedding sand to order.DIY & HomeRoof Pitch CalculatorRoof pitch as x/12, angle in degrees and percent slope from rise and run, plus the pitch factor and rafter length.DIY & HomeRoofing CalculatorRoof area from the house footprint and pitch, roofing squares and bundles of shingles to buy.DIY & HomeSquare Footage CalculatorArea of up to four rooms or rectangles in feet and inches or metres, with cost per square foot.DIY & HomeStair CalculatorNumber of steps, riser height, tread run, stringer length and angle from the total rise, checked against code limits.DIY & HomeTile CalculatorNumber of tiles and boxes for a floor, wall, shower or backsplash, with grout joints and waste.DIY & HomeVoltage Drop CalculatorVoltage drop in volts and percent for a copper or aluminum wire run, the voltage left at the load, and the smallest gauge that stays under 3%.DIY & HomeWater Heater Size CalculatorSize a tank water heater by first hour rating (peak-hour demand) or a tankless heater by flow rate and temperature rise.DIY & HomeWire Size CalculatorMinimum copper or aluminum wire gauge (AWG) for a circuit from the amps, distance and voltage, checked for ampacity and voltage drop.