Engineering Calculators
Last updated: October 2026
Pump Power & Efficiency Calculator
Find the shaft power (kW) needed to drive a pump given flow rate, head, fluid density, and combined pump-motor efficiency.
Power Transmission Calculator
Converts torque (N·m) and rotational speed (rpm) into mechanical power in kilowatts.
HVAC Duct Sizing Calculator
Size a supply or return duct from the airflow in CFM by the velocity method or the equal-friction method: round duct diameter, the rectangular equivalent at your aspect ratio, the nearest standard size and the velocity and friction rate it will actually run at.
HVAC Heat Load Calculator
Estimates the heating or cooling load for a room or building in BTU/hr based on floor area, ceiling height, insulation quality, temperature difference, and window area.
Convective Heat Transfer Calculator
Calculate convective heat transfer rate from a solid surface to a flowing fluid (or vice versa) using Newton's law of cooling.
Transformer Losses Calculator
Calculate the operating efficiency of a power transformer at any load factor, accounting for both iron (no-load) and copper (load-dependent) losses.
Heat Conduction Calculator
Compute the steady-state heat flow rate through a flat material layer using Fourier's Law.
Thermal Expansion Calculator
Calculates how much a material elongates when its temperature changes, using the linear thermal expansion formula.
Pipe Flow Rate Calculator
Determine the flow rate of water through a pipe using the Hazen-Williams equation.
Pump Power Calculator
Calculate the shaft power and motor input power needed to pump a fluid against a given head.
Ohm's Law Solver (V = IR)
Solve Ohm's law for voltage, current or resistance: pick the unknown, enter the other two values and get V = I × R rearranged for you.
Soil Bearing Capacity Calculator
Estimate the ultimate bearing capacity of soil beneath a square footing with the general bearing-capacity equation in Terzaghi's square-footing form, using Prandtl–Reissner and Brinch Hansen bearing-capacity factors.
Heat Loss Calculator (U × A × ΔT by Surface)
Work out a room or house's design heat loss surface by surface: walls, ceiling, floor and windows from their R-values or U-factors, plus air infiltration, at your indoor and outdoor design temperatures.
Furnace Size Calculator (BTU Input from Heat Loss and AFUE)
Turn a design heat loss into the furnace you should shop for: required heat output with a sizing margin, the nameplate input BTU/h at your AFUE, the nearest standard furnace size and its real output.
Beam Deflection Calculator
Calculate the maximum deflection of a simply supported beam under a point load, uniformly distributed load (UDL), or end load using standard Euler-Bernoulli beam theory.
Concrete Mix Design Calculator
Estimates the total cement mass required for a concrete pour based on volume and target strength.
Pressure Vessel Wall Thickness Calculator
Determines the minimum wall thickness required for cylindrical or spherical pressure vessels under internal pressure.
Pump Head Calculator
Determine the total dynamic head and shaft power needed to move fluid through a piping system.
Pipe Pressure Drop Calculator
Compute the frictional pressure drop along a straight pipe section using the Darcy-Weisbach equation.