Travel & Automotive

Fuel Cost Calculator

Calculate total fuel cost and amount of fuel needed for any trip based on distance, mileage, and price.

Mileage Calculator

Calculate your vehicle fuel mileage in km/L, L/100km, or miles per gallon (mpg).

Tire Size Calculator

Calculate tire dimensions from tire code including section width, aspect ratio, sidewall height, and overall diameter. Compare two tires visually.

Engine Horsepower Calculator

Estimate engine horsepower using quarter-mile elapsed time and trap speed methods. Free online engine horsepower calculator with instant results.

Airplane Weight Shift Calculator

Calculate how shifting cargo, baggage, or passengers affects the center of gravity of an aircraft using the weight shift formula.

Crawl Ratio Calculator

Calculate crawl ratio using differential, transfer case, and transmission low gear ratios. Essential for off-road 4x4 gearing setup.

Dyno Correction Factor Calculator

Calculate SAE J607/J1349 dyno correction factor for naturally aspirated engines. Correct observed horsepower to standard atmospheric conditions.

Effective Gear Ratio Calculator

Calculate the effective gear ratio after changing tire size. Solve for effective ratio, old tire diameter, new tire diameter, and gear ratio with our online effective gear ratio calculator.

Engine Displacement Calculator

Calculate engine displacement from bore, stroke, and cylinder count. Solve for bore or stroke with unit conversions.

ET Method Horsepower Calculator

Calculate the change in horsepower between before and after quarter-mile ET times using the empirical ET method formula.

Fuel Injector Size Calculator

Calculate the right fuel injector size for your engine build using the HP/16 rule of thumb with support for forced induction and E85 scaling.

Gas Mileage Calculator

Calculate your vehicle fuel economy in MPG, km/L, or L/100km and estimate trip fuel costs.

Gear Ratio Speed Calculator

Calculate vehicle speed from RPM, tire size, and gear ratio. Solve for speed, engine RPM, gear ratio, or tire radius using the v = (r × RPM) / (168 × G) drivetrain equation.

Power to Weight Ratio Calculator

Calculate power to weight ratio for vehicles and engines. Compute PWR in horsepower per ton or watts per kilogram with customizable inputs.

Suspension Spring Rate Calculator

Calculate coil spring rates for automotive suspension using the helical spring formula. Solve for spring rate, wire diameter, coil diameter, or active coils.

0-60 Quarter Mile Calculator

Estimate 0-60 mph acceleration time and quarter-mile elapsed time from horsepower and curb weight. Free online car performance calculator.

Flight Distance Calculator

Calculate great-circle air distance between cities or airports with flight time estimation, aircraft speed profiles, and route allowance.

Hiking Pace Calculator (Naismith's Rule)

Calculate your hiking pace using Naismith's Rule. Plan your hike with accurate time estimates accounting for distance, elevation gain, terrain difficulty, and pack weight. Free online hiking calculator.

ETA Calculator

Estimate the remaining duration and completion time for file transfers, downloads, or batch tasks with a real-time progress simulator.

AFR Calculator

Calculate the stoichiometric air-fuel ratio for common fuels including methane, propane, octane, hydrogen, and more with customizable fuel composition.

Torque to Horsepower Converter

Calculate horsepower from torque and RPM using the standard mechanical power formula in real time.