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Calculators for Real Home Projects

Free, instant and honest: every calculator shows its assumptions, its waste allowance and the plain-English maths behind the number. Pick the project you're working on.

Concrete Slab & Footing Concrete & Building Cubic yards, cubic meters, 60 lb / 80 lb bag counts, #4 rebar grid requirements, and total material cost — including a waste factor. Built for patios, driveways, footings, shed pads, and walkways.

Paint & Primer Coverage Painting & Walls Auto-deducts doors and windows, applies coat multiplier, returns gallons and liters needed for walls and ceiling.
Drywall Sheet & Screws Painting & Walls Estimates 4×8 or 4×12 sheets based on room perimeter, joint compound buckets, tape rolls, and screw counts.

Tile Layout & Mortar Flooring Dynamic Canvas visualizer of tile grid, plus thinset bags, grout pounds, and waste overage — for any tile size.

Mulch & Topsoil Bulk Garden & Outdoor Compares bulk delivery vs. bagged pricing for any bed shape — rectangle or circle — with depth in inches or centimeters.

Solar Panel System Sizing Roofing & Solar Panel count from roof area, system size in kW, annual kWh production, and estimated payback period — with sun-hours and efficiency loss built in.

Coming tools: Roofing material estimator · insulation coverage · deck lumber · electrical load (NEC 220) · water heater & pipe volume.

Calculators for Real Home Projects

Concrete Slab & Footing Calculator

Paint & Drywall Calculators

Tile Layout & Mortar Calculator

Mulch & Topsoil Estimator

Solar Panel Sizing Calculator

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