Engineering Calculators
Civil, structural, mechanical, electrical, plumbing, HVAC and surveying calculators built on standard engineering formulas with SI units and step-by-step working.
About Engineering Calculators
The OneCalc Engineering suite brings design-office grade calculations into the browser. Every tool is written against published codes and standards, shows the governing equation, the substituted values and the final result in SI units.
Nothing is uploaded to a server: inputs stay on your device, so the calculators work equally well on a site laptop with a weak connection or on a phone during an inspection.
Featured Calculators
Concrete Mix Quantity
Cement, sand and aggregate for any grade and volume
Beam Deflection
Maximum deflection for simply supported and cantilever beams
Voltage Drop
Cable voltage drop for single and three phase circuits
HVAC Cooling Load
Room heat load and required tonnage estimation
Categories
Civil Engineering
Concrete mix, brickwork, earthwork, slab and footing quantities
Structural Engineering
Beam bending, deflection, column load and steel section checks
Mechanical Engineering
Stress, torque, gear ratio, belt drive and thermal expansion
Electrical Engineering
Cable sizing, voltage drop, load, power factor and transformer
Plumbing
Pipe sizing, flow rate, head loss, pump duty and tank capacity
HVAC
Cooling load, duct sizing, air changes, CFM and tonnage
Surveying
Levelling, traverse, area by coordinates, bearings and contours
Popular Calculators
Recently Added
Frequently Asked Questions
Explore what is live today
While these tools are being built, use the converters and engineering suites already available on OneCalc.