Engineering calculators
Use educational idealised models for energy, power, motion and simple DC circuits.
Choose the right tool
Match each input to its SI unit. Watt-hours describe stored energy; watts describe a rate of energy use. DC power formulas do not automatically handle AC power factor.
Before you calculate
These tools do not assess electrical safety, equipment suitability or structural safety. Real losses, tolerances and changing conditions require further modelling.
20 calculators
Ohm's law voltage ↗
Calculate voltage across an ideal resistive component.
EngineeringOhm's law current ↗
Calculate DC current through an ideal resistor.
EngineeringOhm's law resistance ↗
Infer ideal resistance from voltage and current.
EngineeringDC electrical power ↗
Calculate power from DC voltage and current.
EngineeringThree resistors in series ↗
Add ideal resistances connected in series.
EngineeringTwo resistors in parallel ↗
Calculate the equivalent resistance of two ideal parallel resistors.
EngineeringBattery nominal energy ↗
Convert nominal battery voltage and amp-hours into watt-hours.
EngineeringBattery runtime scenario ↗
Estimate runtime from usable energy and a constant load.
EngineeringAppliance energy use ↗
Calculate energy consumed by a constant-power appliance.
EngineeringAppliance running cost ↗
Estimate energy cost from average power, duration and entered tariff.
EngineeringSolar daily energy scenario ↗
Model daily generation from rated capacity and entered conditions.
EngineeringForce from mass and acceleration ↗
Calculate net force using Newton's second law.
EngineeringKinetic energy ↗
Calculate translational kinetic energy.
EngineeringGravitational potential energy change ↗
Estimate energy gained by raising a mass in uniform gravity.
EngineeringLinear momentum magnitude ↗
Calculate classical linear momentum magnitude.
EngineeringPressure from force and area ↗
Calculate average pressure over an area.
EngineeringMaterial density ↗
Calculate average density from mass and volume.
EngineeringMechanical work by constant force ↗
Calculate work when constant force acts along displacement.
EngineeringAverage mechanical power ↗
Calculate average power from work and elapsed time.
EngineeringPeriod from frequency ↗
Find one cycle's duration from frequency.