Engineering calculators for electrical, mechanical, and structural work
Calculate Ohm's law, electrical power, voltage drop, wire size, battery runtime, motors, torque, horsepower, gears, hydraulic force, pressure, pipe flow, Reynolds number, heat transfer, thermal expansion, beam deflection, stress, strain, factor of safety, density, slope, wavelength, and decibels. Each page includes formulas, examples, result details, FAQs, and structured data.
Search by calculator name, topic, formula, or design check.
Electrical engineering
13 calculators
Ohm's Law Calculator
Calculate voltage, current, resistance, and circuit relationships using Ohm's law.
Open calculatorVoltage Calculator
Estimate voltage from current and resistance for electrical engineering checks.
Open calculatorCurrent Calculator
Calculate current from voltage and resistance in simple circuit models.
Open calculatorResistance Calculator
Estimate resistance from voltage and current using Ohm's law.
Open calculatorElectrical Power Calculator
Calculate watts, kilowatts, and current from voltage, amperage, and power factor.
Open calculatorAC Power Calculator
Estimate real power for AC circuits using voltage, current, and power factor.
Open calculatorVoltage Drop Calculator
Estimate voltage drop over conductor length from current and resistance per foot.
Open calculatorWire Size Calculator
Estimate conductor area from load current and allowable current density.
Open calculatorResistor Series Calculator
Calculate equivalent resistance for resistors connected in series.
Open calculatorResistor Parallel Calculator
Calculate equivalent resistance for resistors connected in parallel.
Open calculatorCapacitor Energy Calculator
Estimate stored capacitor energy and charge from capacitance and voltage.
Open calculatorBattery Runtime Calculator
Estimate battery operating time from capacity, load, and usable efficiency.
Open calculatorTransformer Calculator
Calculate transformer voltage, current, and turns-ratio relationships.
Open calculatorMechanical engineering
10 calculators
Motor Horsepower Calculator
Estimate motor horsepower from voltage, current, efficiency, and power factor.
Open calculatorMotor Efficiency Calculator
Calculate motor or machine efficiency from input and useful output power.
Open calculatorEfficiency Calculator
Calculate useful output percentage from input energy or power.
Open calculatorTorque Calculator
Convert torque and rotational speed into power output.
Open calculatorTorque to Horsepower Calculator
Estimate horsepower from torque and RPM for rotating equipment.
Open calculatorRPM Calculator
Estimate rotational speed relationships from torque and power.
Open calculatorGear Ratio Calculator
Calculate gear ratio, output RPM, and torque multiplication from gear teeth.
Open calculatorPulley Ratio Calculator
Estimate speed ratio and output RPM for belt and pulley systems.
Open calculatorMechanical Advantage Calculator
Calculate force multiplication for simple machines and mechanical systems.
Open calculatorLever Calculator
Estimate lever mechanical advantage from input and output force.
Open calculatorFluid engineering
10 calculators
Pressure Calculator
Calculate pressure from applied force and contact area.
Open calculatorForce Calculator
Estimate force from pressure and area relationships.
Open calculatorHydraulic Force Calculator
Calculate hydraulic cylinder force from pressure and piston area.
Open calculatorHydraulic Pressure Calculator
Estimate hydraulic pressure required for a target force and piston area.
Open calculatorFlow Rate Calculator
Calculate volumetric flow rate from cross-sectional area and fluid velocity.
Open calculatorPipe Flow Calculator
Estimate pipe flow using area and velocity for liquid or air systems.
Open calculatorPipe Velocity Calculator
Calculate fluid velocity from flow rate and pipe area.
Open calculatorReynolds Number Calculator
Calculate Reynolds number and classify laminar or turbulent flow.
Open calculatorBernoulli Calculator
Estimate dynamic pressure from density and velocity using Bernoulli relationships.
Open calculatorDynamic Pressure Calculator
Calculate velocity pressure for air, water, and moving fluids.
Open calculatorThermal engineering
7 calculators
Heat Transfer Calculator
Estimate heat transfer rate from U-value, area, and temperature difference.
Open calculatorConduction Calculator
Calculate conduction-style heat transfer through a material layer.
Open calculatorThermal Expansion Calculator
Estimate material expansion from length, coefficient, and temperature change.
Open calculatorHeat Capacity Calculator
Calculate heat energy needed to change material temperature.
Open calculatorSpecific Heat Calculator
Estimate heat energy from mass, specific heat, and temperature change.
Open calculatorCooling Load Calculator
Estimate cooling load from heat transfer area and temperature difference.
Open calculatorBTU Calculator
Calculate heat energy in engineering units from mass and temperature change.
Open calculatorStructural engineering
7 calculators
Beam Deflection Calculator
Estimate simply supported beam deflection under a center load.
Open calculatorBeam Load Calculator
Estimate beam load relationships from span, stiffness, and deflection.
Open calculatorStress Calculator
Calculate engineering stress from force and cross-sectional area.
Open calculatorStrain Calculator
Estimate elastic strain from stress and modulus of elasticity.
Open calculatorYoung's Modulus Calculator
Estimate modulus-style material stiffness from stress and strain.
Open calculatorFactor of Safety Calculator
Calculate factor of safety from strength and working stress.
Open calculatorAllowable Stress Calculator
Estimate allowable working stress from strength and safety factor.
Open calculatorMaterials engineering
5 calculators
Density Calculator
Calculate density from mass and volume for materials and fluids.
Open calculatorMass Calculator
Estimate mass from material density and volume.
Open calculatorVolume Calculator
Estimate volume from mass and density for engineering materials.
Open calculatorMaterial Weight Calculator
Calculate material weight from density, volume, and gravity assumptions.
Open calculatorLoad Calculator
Estimate working load and capacity margins for engineering components.
Open calculatorCivil engineering
4 calculators
Slope Calculator
Convert rise and run into slope percent and angle.
Open calculatorGrade Calculator
Calculate grade percentage, angle, and rise-run relationships.
Open calculatorAngle Calculator
Estimate engineering angle from rise and run dimensions.
Open calculatorSurvey Slope Calculator
Calculate survey-style slope from elevation change and horizontal distance.
Open calculatorSignals and acoustics
5 calculators
Frequency Calculator
Calculate wave frequency, wavelength, and speed relationships.
Open calculatorWavelength Calculator
Convert frequency and wave speed into wavelength.
Open calculatorDecibel Calculator
Estimate sound level difference from distance ratio.
Open calculatorSound Level Calculator
Calculate point-source sound level change over distance.
Open calculatorResonant Frequency Calculator
Estimate resonant frequency-style wave relationships.
Open calculatorGeneral engineering
2 calculators