Building & renovation
Quantities and costs for paint, tiles, concrete, insulation and the rest of a renovation shopping list. 40 tools, including Beam Load Calculator, Belt length calculator (pulleys), Board Foot Calculator and Bolt Torque Calculator. All free, with no account and nothing to install.
Beam Load CalculatorEstimate the maximum moment, deflection, bending stress and demand/capacity ratio of a beam for seven load cases — a preliminary check, not a design.Belt length calculator (pulleys)Find the belt length wrapping two pulleys, for an open (same-direction) or crossed (reversed) drive. Enter both pulley diameters and the centre distance to get the belt length, and add a driver speed to read the driven pulley RPM and the linear belt speed.Board Foot CalculatorWork out board feet from thickness, width and length, with quarter notation, metric entry, 30 wood species, moisture content and price.Bolt Torque CalculatorGet the tightening torque of a metric or UNC bolt from its grade, tensile stress area, target preload and lubrication, in N·m and lb·ft side by side.Brick calculatorEstimate the number of bricks for a wall from its area and brick size.BTU calculator (air conditioning)Estimate the air-conditioner power in BTU and kW needed to cool a room.Carpet CalculatorEstimate carpet, padding and installation cost for rectangular, L-shaped or multi-room floors. Measure in feet+inches, inches, yards, metres or centimetres, read the area in ft², yd² and m² at once, price per sq ft or per m², and pick a 12/15 ft US roll or a 4/5 m European one.Concrete blocks calculatorEstimate the number of concrete blocks needed to build a wall.Concrete calculatorWork out the volume of concrete and number of bags for a slab or foundation.Conduit fill calculator (NEC)Check whether your conductors fit a conduit under the US National Electrical Code. Pick the conduit type and trade size, enter how many THHN conductors of a given gauge you're pulling, and it computes the percentage fill against the NEC limit (53 % / 31 % / 40 %) with a clear pass or fail.Cubic yard calculatorHow much concrete, gravel, soil or mulch fills an area to a given depth. Enter length and width in feet and the depth in inches; it returns the volume in cubic yards (how material is sold in the US) and cubic feet.Decking boards calculatorEstimate how many decking boards you need for a deck area, including waste.Deck stain calculatorHow much stain a deck needs: the surface area of the boards, the railing and the stairs, divided by the coverage of your stain — which drops for solid stains and for rough or weathered wood — times the number of coats. Enter dimensions and it returns the gallons and, optionally, the cost.Drywall calculatorEstimate the number of drywall sheets needed for a wall or ceiling area.Fence calculatorEstimate the number of posts and panels for a fence of a given length.Flooring calculatorWork out how many packs of flooring you need for a room, including waste.Gravel calculatorEstimate the volume and weight of gravel needed to cover an area.Lumber Calculator (nominal vs actual size)See why a 2×4 is really 1½ × 3½ inches, then size boards for a deck, a fence, shelving or wall framing with waste and pricing.Miter Angle CalculatorFind the miter (and bevel for crown molding) saw angles for any corner, from the corner angle and spring angle.Paint calculatorEstimate how many litres of paint and cans you need for your walls.Paver CalculatorWork out how many pavers you need to cover an area, including a waste allowance.Pipe Flow Calculator (Hazen-Williams & Darcy-Weisbach)Solve for flow rate, velocity or pressure drop in a full pipe, in imperial or metric units, by Hazen-Williams, by Darcy-Weisbach with an iterated Colebrook-White friction factor, or by both side by side. Reports the Reynolds number and the flow regime — and refuses to print a Hazen-Williams number outside its validity range (water near 15 °C, turbulent flow), which is where most pipe calculators quietly mislead.Pool volume calculatorCompute the water volume of a rectangular pool in cubic metres, litres and gallons.Post Hole Concrete CalculatorEstimate the concrete needed to set fence posts, allowing for the volume taken up by the post.Rainwater harvesting calculatorEstimate how much rainwater you can collect from a roof area and rainfall.Rebar CalculatorCount the bars each way in a slab from its size, spacing and cover, then get the laps, the stock bars to buy and the total steel weight.Retaining Wall CalculatorCount the blocks, courses, base gravel, drainage stone and geogrid layers for a segmental retaining wall — with the engineering limits spelled out.Roof pitch calculatorTurn a roof's rise and run into an angle, a percentage and an X:12 pitch.Roofing shingles calculatorEstimate the number of shingle bundles needed to cover a roof, with waste.Sand CalculatorEstimate the volume and weight of sand needed to cover an area to a given depth.Slope and Grade CalculatorConvert between rise/run, slope percentage, angle and ratio for ramps, roofs, driveways and drainage.Sod calculatorHow much sod (turf) to order for a lawn: enter the area — rectangle, circle or triangle — and it works out the square footage, the pieces, rolls and pallets you need with a waste allowance, and optionally the cost. No more guessing at the garden centre.Square Footage CalculatorCalculate area in ft², m² and yd² at the same time for rectangles, triangles, circles, trapezoids, ellipses, L-shapes and multiple rooms. Enter feet+inches, inches, yards, metres or centimetres — the Imperial/Metric switch converts what you typed — and price per sq ft or per m².Squareness Checker (3-4-5 Rule)Check whether a corner is square using the 3-4-5 rule: compare the measured diagonal to the expected one and read the corner angle.Stair calculatorWork out the number of steps and the exact riser height from a total rise.Steel Weight CalculatorWeigh round, square, hex and flat bar, plate, pipe, square and rectangular tube and angle in steel, stainless, aluminium, brass or copper.Tile calculatorFind out how many tiles you need for a floor or wall, including waste.Tile Grout CalculatorWork out how much tile grout you need by weight, volume and number of bags from tile size, joint width and depth, area and wastage.Wall framing studs calculatorEstimate how many vertical studs you need for a wall at a given spacing.Wallpaper calculatorEstimate how many rolls of wallpaper you need for a room, including waste.