Free construction calculators
Measure once. Buy the right amount.
Estimate common construction and landscaping materials with clear formulas, adjustable waste allowances, and practical purchase rounding.
General calculator
Choose a job and enter your measurements
Switch between US and metric inputs. Results are planning estimates and should be checked against the selected product and field conditions.
Material guides
Learn the formula behind each estimate
Each guide explains what to measure, common allowances, purchase units, and limitations that can change the final quantity.
Mulch Calculator
Find cubic feet, cubic yards, or bags of mulch from a measured bed area and installation depth.
Concrete Calculator
Estimate ready-mix concrete volume and an approximate number of 80-pound bags.
Gravel Calculator
Calculate cubic yards and approximate tons for a compacted gravel layer.
Paint Calculator
Estimate gallons using paintable area, coat count, and the manufacturer's coverage rate.
Drywall Calculator
Estimate full sheets from total surface area, sheet size, and a cutting allowance.
Flooring and Tile Calculator
Estimate flooring cartons from room dimensions, package coverage, and cutting waste.
Roofing Calculator
Convert measured sloped roof area into roofing squares and shingle bundles.
Wall Framing Calculator
Estimate wall studs from wall length, on-center spacing, openings, and extras.
Insulation Calculator
Estimate insulation packages using net cavity area and package coverage.
How JobMath helps