± JoistCalc

No sign-up · No paywall · Built for the field

Free calculators that get the numbers right.

Concrete yardage, gravel tonnage, board footage, drywall sheets, paint gallons, roofing squares, pipe volume, wire sizing, BTU load, flooring boxes, insulation coverage — measure it, enter it, order the right amount the first time.

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01

Concrete

Slabs, footings, columns & steps — cubic yards and bag count.

 02

Gravel & Aggregate

Base, driveway fill, and landscape rock by the ton.

 03

Lumber & Framing

Board footage and wall stud counts on-center.

 04

Drywall

Sheet count, screws, and joint compound by room.

 05

Paint

Gallons needed by wall area, coats, and coverage rate.

 06

Roofing

Squares and bundles adjusted for roof pitch.

 07

Plumbing

Pipe water volume and drain-line slope & fall.

 08

Electrical

Voltage drop and residential wire/breaker sizing.

 09

HVAC

Room BTU load and round duct sizing.

 10

Tile & Flooring

Square footage and box count for any flooring.

 11

Insulation

Batt/roll bags, or spray foam board feet and kits.
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Also hauling material or running a rig? Try PitStopCalc — our free sister site for diesel/gas engines, towing, gear ratios, and more.

Built for accuracy on the jobsite

Every calculator on this site uses standard industry formulas and material densities, the same math a foreman would use with a tape measure and a notepad. Enter measurements in feet and inches, pick your material or shape, and get a straight answer — yardage, tonnage, board feet, sheets, gallons, or bundles — plus a waste-factor buffer so you're not making a second supply run.

Results are estimates for planning purposes. Always confirm quantities against your project specs, local supplier minimums, and manufacturer coverage rates before ordering.