23 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.
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