Automotive Calculators
0-60 Time Calculator
Estimate a vehicle's 0-60 mph acceleration time from its weight, engine power, and drivetrain efficiency using a physics-based work-energy time formula.
Boat Fuel Consumption Calculator
Calculate marine engine fuel consumption and trip cost from burn rate and trip duration, or from cruising distance and speed, in gallons or liters used.
Brake Horsepower Calculator
Convert dyno-measured engine torque and RPM into brake horsepower using the standard crank-measured BHP formula, in imperial or metric units, as chosen.
Car Loan Calculator
Calculate monthly auto loan payments and total interest cost from vehicle price, sales tax, down payment, trade-in value, APR rate, and loan term length.
Compression Ratio Calculator
Calculate an engine's compression ratio from swept and clearance volume, or derive swept volume first from cylinder bore and stroke measurements taken.
Electric Vehicle Range Calculator
Estimate an electric vehicle's remaining driving range from battery capacity, an efficiency rating, and the current battery charge percentage left over.
EV Charging Cost Calculator
Calculate the true cost to charge an EV battery between a set start and target charge percentage, accounting for charger efficiency losses in the total.
Fuel Cost Calculator
Work out exactly what a trip will cost at the pump using trip distance, your vehicle's real-world fuel economy, and the local price per gallon or liter.
Fuel Economy Calculator
Convert and calculate fuel economy figures across MPG (US), MPG (UK), L/100km, and km/L using exact, non-approximated conversion factors between units.
Gear Ratio Calculator
Calculate a vehicle or machinery gear ratio from tooth counts or from input and output RPM, and see how the ratio trades acceleration against top speed.
Horsepower Calculator
Calculate horsepower from torque and RPM using the standard dyno formula, or estimate it from vehicle weight and quarter-mile trap speed test result data.
Lease Payment Calculator
Estimate monthly lease payments from vehicle price, residual value, money factor, and lease term, with the depreciation and finance fee shown separately.
Mileage Calculator
Track fuel efficiency across multiple fill-ups and calculate real-world MPG or L/100km from odometer distance traveled and the fuel actually used each time.
RPM Calculator
Calculate engine RPM at a given road speed from transmission gear ratio, final drive (axle) ratio, and tire diameter, in imperial or metric units used.
RPM to Speed Calculator
Calculate road speed from engine RPM, transmission gear ratio, final drive (axle) ratio, and tire diameter, in either mph or km/h units, whichever chosen.
Stopping Distance Calculator
Calculate total vehicle stopping distance by combining reaction distance and braking distance, based on speed, reaction time, and road surface grip level.
Torque Calculator
Calculate torque from a known horsepower and RPM figure, or directly from an applied force and lever arm distance, in imperial or metric units, either way.
Torque to Horsepower Calculator
Convert any torque and RPM reading directly into horsepower using the standard SAE dyno conversion formula, in imperial or metric units, whichever chosen.
From Engine Bay Math to the Monthly Payment
Automotive calculations split into two very different worlds that this category covers side by side: the physics of what an engine and drivetrain can actually do — horsepower, torque, compression ratio, gear ratio — and the financial math of owning the car once it's built, from loan payments to real-world fuel cost. Eighteen calculators cover both sides for drivers, gearheads, and shoppers alike.
Popular Automotive Calculators
Highlights from performance, efficiency, and finance:
- Horsepower Calculator — converts torque and RPM into horsepower, or works backward from a known power figure.
- 0-60 Time Calculator — estimates acceleration performance from weight, power, and drivetrain characteristics.
- Gear Ratio Calculator — finds the ratio between engine RPM and wheel speed for a given gear.
- Car Loan Calculator — breaks a loan amount, rate, and term into a monthly payment and total interest cost.
- EV Range Calculator — estimates real-world driving range from battery capacity and efficiency, accounting for factors that reduce it below the EPA rating.
Why Horsepower and Torque Get Confused
Torque is the twisting force an engine produces at a given moment, while horsepower is torque multiplied by RPM — which is why a diesel truck engine can have huge torque at low RPM for towing, while a high-revving sports car engine reaches its horsepower peak much higher up the rev range despite lower peak torque. Compression ratio ties into both: raising it generally increases efficiency and power potential, but pushes an engine closer to the fuel's knock limit, which is why higher-compression engines often require premium fuel.
Frequently Asked Questions
Why is my real-world fuel economy worse than the window sticker number?
EPA ratings use standardized test cycles that don't fully capture hard acceleration, cold starts, high speeds, or heavy accessory use, all of which lower real-world mileage.
Does a car loan calculator account for taxes and fees?
Only if you include them in the loan amount — sales tax, registration, and dealer fees are often rolled into financing and should be added to the principal before calculating payments.
Explore More
Planning a marine engine build instead? See the Marine & Nautical Calculators, or check the underlying force and motion equations in the Physics Calculators.