Construction Calculators

Calculate how many gallons of paint you need for a room or surface.

Calculate how much flooring material you need for any room.

Calculate cubic yards of concrete needed for slabs, footings, and columns.

Calculate cubic yards and tons of gravel, mulch, or soil for landscaping.

Calculate the number of posts, rails, and pickets needed for a fence.

Calculate shingles, felt, and nails needed for a roofing project.

Calculate the number of steps, rise, run, and angle for a staircase.

Calculate boards, joists, posts, and screws needed to build a deck.

Calculate rolls of wallpaper needed for a room with pattern repeat waste.

Calculate tiles, grout, and adhesive needed for a floor or wall project.

Calculate board feet and cost for lumber purchases.

Calculate the BTU and tonnage needed to heat or cool a room.

Calculate drywall sheets, joint compound, and tape needed for any room.

Calculate insulation R-value, thickness, quantity, and cost by climate zone.

Calculate plumbing pipe size based on fixture units per UPC standards.

Calculate total electrical load and recommended panel size per NEC standards.

Calculate blocks, cap stones, gravel, and backfill for a retaining wall.

Calculate miter and corner angles for any polygon frame, box, or molding project.

Calculate wood moisture content from wet and oven-dry weights using the standard MC formula.

Calculate tangential and radial wood shrinkage by species as it dries from green to target MC.

Calculate the weight of any wood board or panel by species, dimensions, and quantity.

Calculate how many strips you can rip from a board accounting for saw blade kerf waste.

Calculate stile, rail, and panel dimensions for Shaker-style cabinet doors with tongue-and-groove joinery.

Calculate how many pounds and bags of grout you need for a tile job based on tile size, joint width, and depth.

Calculate square yards of carpet needed for a room including waste and determine whether you will need a seam.

Calculate linear feet of baseboard or trim molding for any room, accounting for door openings, waste, and stick length.

Calculate squares of siding needed for walls and gables, subtracting windows and doors and adding a waste factor.

Calculate linear feet of gutter and number of downspouts needed for your home based on eave lengths and gutter size.

Calculate the right tank size or tankless flow rate for your home based on household size, bathroom count, and peak-hour demand.

Calculate swimming pool volume in gallons and liters for rectangular, round, oval, and kidney-shaped pools.

Estimate the cost of a kitchen remodel by size, tier, custom cabinets, and plumbing/electrical relocation, with a component breakdown.

Estimate the cost of a bathroom remodel by size, tier, new shower, walk-in tub, and plumbing relocation.

Calculate required attic net free area (NFA) per IRC R806.2 for balanced 1:300 or unbalanced 1:150 ventilation, split between soffit and ridge vents.

Calculate how many solar panels fit on your roof, estimated kW capacity, and annual kWh output.

Calculate rebar quantity, spacing, linear feet, and weight for concrete slabs and footings.

Calculate concrete mix ratio of cement, sand, gravel, and water for target PSI strength.

Calculate max beam moment, required section modulus, and recommended beam size for a given span and load.

Calculate window U-value and R-value from glass layers, gap type, and frame material.

Calculate required slope percentage and drop per foot for drainage pipes by diameter.

Calculate number of bricks or blocks needed for a wall from dimensions, unit type, and openings.

Calculate minimum septic tank size from bedrooms, occupants, and daily water usage.

Calculate tons of hot-mix asphalt needed for driveways, parking lots, and roads from length, width, and depth.

Calculate cubic yards of soil to remove for foundations, pools, and trenches, with swell factor for hauling.

Calculate how many pavers you need plus base gravel and sand for a patio, walkway, or driveway.

Calculate board feet for hardwood lumber with quarter-grade thickness notation, plus cubic meters for international buyers.

Calculate rafter length, rise, and plumb-cut angle from building run, roof pitch, and overhang.

Convert between roof pitch (x/12), angle in degrees, and grade percentage for any roof slope.

Calculate how many studs, plates, and headers you need for a framed wall at 16" or 24" on center.

Calculate how many 4x8 or 5x10 plywood sheets you need for subfloors, sheathing, or decking with waste allowance.

Calculate floor joist count, linear feet, board feet, and the maximum IRC span for common sizes and species.

Calculate NEC voltage drop percentage and line loss for any wire run by AWG, amps, distance, and copper or aluminum.

Calculate the NEC maximum number of THWN-2 wires that fit in EMT, IMC, RMC, or PVC conduit by trade size.

Calculate water pressure loss and head loss in PVC, copper, PEX, or steel pipe using the Hazen-Williams equation.

Calculate whole-house heat loss through walls, roof, windows, and floor in BTU/hr and kilowatts.

Calculate round or rectangular duct size from airflow (CFM) and velocity for residential HVAC design.

Calculate required spread footing size from column load and soil bearing capacity for foundations and decks.

Calculate how many tubes of caulk or sealant you need for any joint length, width, and depth.

Calculate linear feet of crown molding or trim needed for a room, accounting for doors, windows, and waste.

Calculate required chimney flue area and round or square ID from appliance BTU rating per NFPA 211.

Whole-house cooling load for AC sizing including solar gain, people, lights, and appliances (Manual J lite).

Derate heat pump BTU capacity at actual outdoor temperature for cold climate and standard air-source heat pumps.

Convert between SEER, SEER2, EER, EER2, HSPF, HSPF2, and COP for heat pumps and air conditioners.

Calculate dehumidifier pints per day from room area and humidity class per AHAM guidelines.

Calculate dew point, wet bulb, humidity ratio, and enthalpy from dry bulb temperature and relative humidity.

Calculate ACH (air changes per hour) from room volume and CFM for ventilation and infiltration design.

Calculate required whole-house mechanical ventilation CFM per ASHRAE 62.2-2022 by floor area and bedrooms.

Calculate actual radiator BTU output at any water temperature and room temperature for hydronic heating systems.

Estimate annual heating cost by fuel type (natural gas, propane, oil, electric, wood) using heat loss and heating degree days.

Calculate total external static pressure for residential HVAC systems from duct friction, fittings, filter, and coil.

Calculate the required generator size in watts and kilowatts from your appliance loads, including motor starting surge.

Look up NEC Table 310.16 ampacity for copper and aluminum wire by AWG, with temperature and bundle derating.

Calculate PEX tube length, loop count, and BTU output for hydronic radiant floor heating by tube spacing and water temperature.

Calculate the number of drywall screws needed for walls and ceilings by sheet count, framing spacing, and installation type.

Calculate BTU/hr required to melt snow on a heated driveway or sidewalk by area and climate zone per ASHRAE 2015.

Calculate required inverter kW and DC-to-AC ratio from solar panel array watts for grid-tied and off-grid PV systems.

Calculate how long a battery (kWh) will run your loads, accounting for inverter efficiency and depth-of-discharge limits.

Calculate price per square meter, price per square foot, and price per acre from total cost and area. Supports both metric and imperial inpu...

Calculate cost per square foot, cost per square meter, and cost per acre from total project cost and area. Essential for construction and re...