43 free
automotive calculators
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Car Ownership Cost Calculator
Compare two vehicles using depreciation, fuel, insurance, maintenance, financing interest, and fees. See total, monthly, and per-mile or per-km costs.
Ownership costsAuto Loan Calculator
Estimate a fixed-rate car loan payment, total interest, and remaining balance with term comparisons and a yearly repayment breakdown.
Ownership costsAuto Refinance Calculator
Compare keeping your current car loan with refinancing, including fees, monthly payment changes, and total remaining cost.
Ownership costsCar Lease Calculator
Estimate a car lease payment, cash due at signing, and total cost with a breakdown of depreciation, rent charges, taxes, and fees.
Fuel & mileageFuel Cost Calculator
Calculate trip fuel cost and split costs in U.S., metric, or UK units, including Imperial MPG and pounds per litre.
Fuel & mileageMPG Calculator
Calculate fuel economy from a fill-up in miles or kilometers and U.S. gallons, UK gallons, or liters. Get MPG, L/100 km, and km/L.
Fuel & mileageMPG to L/100 km Converter
Convert fuel economy both ways between U.S. MPG, UK MPG, L/100 km, and km/L. Includes formulas and a comparison table.
Fuel & mileageAnnual Fuel Cost Calculator
Estimate annual and monthly fuel spending in U.S., metric, or UK units, with your own fuel price and currency.
Electric vehiclesEV Charging Cost Calculator
Estimate charging-session cost and energy drawn from the wall, including charging losses.
Electric vehiclesEV Charging Time Calculator
Estimate EV charging time from battery capacity, charge range, and average charging power.
Electric vehiclesEV vs Gas Cost Calculator
Compare yearly electricity and gasoline spending for the same driving distance.
Tires & wheelsWheel Offset Calculator
Compare wheel width and offset to estimate inner clearance and outward position changes, with a shared-scale diagram.
Tires & wheelsTire Size Calculator
Calculate nominal tire diameter, sidewall height, circumference, and revolutions per mile.
Tires & wheelsTire Size Comparison Calculator
Compare two tire sizes with a scale diagram, dimension table, and speedometer estimates in mph or km/h.
Engine & drivetrainEngine Displacement Calculator
Calculate engine swept volume in liters, cubic centimeters, and cubic inches from bore and stroke.
Engine & drivetrainHorsepower & Torque Calculator
Calculate horsepower from torque or torque from power at a given RPM. Supports lb-ft, N·m, mechanical hp, kW, and metric PS.
Engine & drivetrainGear Ratio RPM Calculator
Calculate engine RPM from mph or km/h, tire diameter in inches or millimeters, transmission gear, and final drive ratio.
Engine & drivetrainCompression Ratio Calculator
Calculate static engine compression ratio from bore, stroke and total clearance volume per cylinder, with metric or inch dimensions.
Engine & drivetrainMean Piston Speed Calculator
Calculate mean piston speed in meters per second and feet per minute from engine RPM and stroke in millimeters or inches.
Fuel & mileageFuel Range Calculator
Estimate driving range from fuel remaining and measured fuel economy, with a reserve you choose. Supports U.S., UK and metric units.
Fuel & mileageFuel Savings Calculator
Compare annual fuel use and spending at two MPG or L/100 km values. See yearly and monthly savings using your mileage and fuel price.
Electric vehiclesEV Range Calculator
Estimate EV driving range from usable battery capacity, current charge, chosen reserve and battery-side consumption. See miles and kilometers.
Engine & drivetrainRod-to-Stroke Ratio Calculator
Calculate connecting-rod length divided by crankshaft stroke in millimeters or inches. Distinguish rod-to-stroke from rod-to-crank-radius ratio.
Engine & drivetrainEngine Airflow Calculator
Estimate four-stroke engine airflow in CFM and liters per minute from displacement, RPM and entered volumetric efficiency. Includes metric and cubic-inch inputs.
Tires & wheelsWheel RPM Calculator
Convert road speed to wheel RPM, or wheel RPM to speed, using tire revolutions per mile, revolutions per kilometer or rolling circumference.
Engine & drivetrainAerodynamic Drag Power Calculator
Calculate a vehicle’s aerodynamic drag force and power in still air from speed, drag coefficient, frontal area and air density. See newtons, kW and hp.
Engine & drivetrainHill-Climbing Power Calculator
Estimate the extra mechanical power needed to lift a vehicle uphill at steady speed. Enter loaded mass, road grade or angle, and speed in mph or km/h.
Engine & drivetrainVehicle Elevation Energy Calculator
Calculate the mechanical energy needed to raise a loaded vehicle through an elevation gain. Convert kilograms or pounds and meters or feet to kWh, Wh and kJ.
Electric vehiclesEV Charging Efficiency Calculator
Calculate EV charging efficiency and the energy difference between a wall meter and battery energy gained over the same charging session.
Tires & wheelsRolling Resistance Calculator
Estimate tire rolling resistance force, mechanical power and energy per distance from loaded vehicle mass, speed and an entered rolling resistance coefficient.
Engine & drivetrainPower-to-Weight Ratio Calculator
Calculate vehicle power-to-weight ratio in hp per metric tonne, kW per tonne, lb per hp and kg per kW. Supports mechanical hp, metric PS and kW inputs.
Engine & drivetrainBMEP Calculator
Calculate brake mean effective pressure from crankshaft torque and total engine displacement. Compare two- and four-stroke engines in bar, kPa and psi.
Engine & drivetrainInjector Duty Cycle Calculator
Calculate injector duty cycle from pulse width, RPM and the pulse interval for one injector. See repeat period, pulse frequency and remaining off-time.
Engine & drivetrainBSFC Calculator
Calculate brake specific fuel consumption from fuel mass flow and engine brake power. Get results in g/kWh and lb/(hp·h), with metric and imperial inputs.
Tires & wheelsStopping Distance Calculator
Estimate reaction distance, braking distance and total stopping distance from speed, reaction time and constant deceleration. Compare meters and feet.
Engine & drivetrainVehicle Kinetic Energy Calculator
Calculate a car’s translational kinetic energy from mass and speed, plus the energy change when speeding up or slowing down. Results in kJ and Wh.
Engine & drivetrainVehicle Acceleration Calculator
Calculate average vehicle acceleration or deceleration from two speeds and elapsed time. Convert mph, km/h or m/s into m/s² and g.
Engine & drivetrainWheel Torque to Force Calculator
Calculate ideal drive force from wheel torque and effective rolling radius. Compare tire-radius scenarios with clear per-wheel and total-torque guidance.
Tires & wheelsOdometer Correction Calculator
Calculate a trip-distance correction factor from a measured reference route and your odometer reading. Estimate corrected trip miles or kilometers.
Tires & wheelsTire Tread Wear Rate Calculator
Calculate observed tire tread loss per 1,000 miles or kilometers from two depth readings. Compare measurement intervals with mm and 32nds-inch inputs.
Tires & wheelsTire Cost per Mile Calculator
Compare two tire sets by cost per mile or kilometer. Enter total costs and service distances to see cents per distance and an equal-cost distance for Set B.
Engine & drivetrainBrake Thermal Efficiency Calculator
Calculate engine brake thermal efficiency from BSFC and fuel lower heating value. See the energy balance per kWh of crankshaft output, with worked examples.
Engine & drivetrainEngine Mechanical Efficiency Calculator
Calculate engine mechanical efficiency from indicated and brake power in kW or hp. Find the power difference, with matched-measurement guidance and examples.
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