ProCalculator

Stop juggling a dozen single-purpose calculator apps. ProCalculator is a professional calculator toolbox built for contractors, electricians, tradespeople, DIYers, and anyone who needs fast, accurate, real-world calculations — not just arithmetic. CONSTRUCTION • Concrete Calculator — area, volume, and waste-adjusted material quantity • Screed Calculator • Paint Calculator — coverage, coats, and door/window deductions • Tile Calculator — tile count, waste, and boxes to buy • Steel Weight Calculator — 7 shapes (round bar, flat bar, hollow sections, pipe, angle, plate) • Area & Volume Calculator — rectangle, triangle, circle, trapezoid, box, cylinder ELECTRICAL • Ohm's Law Calculator — solve for voltage, current, or resistance • Electricity Cost Calculator — daily, monthly, and annual running cost FINANCE • Percentage Calculator • Discount Calculator • VAT / Tax Calculator — add or remove tax either direction • Compound Interest Calculator CONVERTERS • Unit Converter — length, area, volume, weight, temperature, pressure, power, energy Every calculator shows its formula and the numbers behind the result — not just an answer, but why it's the answer, so you can trust it and explain it to a client or crew. WORKS OFFLINE. NO ACCOUNT NEEDED. ProCalculator never requires a login and never needs an internet connection to calculate. Your saved history, favorites, and projects stay on your device. GO PRO Free unlocks every calculator, unlimited. Pro adds Projects (group related calculations — like a whole renovation or job — with an estimated cost rollup), unlimited saved history, and removes ads. Built for the people who actually use calculators on the job: contractors, electricians, engineers, tradespeople, DIYers, and students. Estimates only — always verify final dimensions and requirements against applicable local codes, manufacturer specifications, and a qualified professional.