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.
Practical calculators for construction, DIY, electrical and finance.