All Calculators
Pick a category or browse them all.
Tire Size & Speedo
Calculate diameter change and speedometer error for lifted/modded vehicles.
Depreciation Curve Pro
Predict the "value floor" of a vehicle to find the best time to buy or sell.
Towing & Payload Margin
Calculate real-world towing capacity after subtracting gear and passengers.
Out-the-Door Price
Find the true cash price including tax, title, and hidden fees.
Fuel & HP Specs
Calculate required fuel injector flow and airflow for performance builds.
Quarter Mile Predictor
Estimate ET and trap speed from horsepower and weight.
Gear Ratio Calculator
RPM at speed, optimal shift points, final drive calculations.
Power-to-Weight Ratio
Compare vehicles and calculate needed HP for target ratio.
Wheel Fitment Calculator
Check offset, poke/tuck, and fender clearance for wheel swaps.
Engine Displacement
Calculate CC or cubic inches from bore, stroke, and cylinders.
Crawl Ratio Calculator
Calculate overall crawl ratio from transmission, transfer case, and axle gears.
Regear Calculator
Find the right axle ratio after upsizing tires.
Repair vs Replace
Is it worth fixing this car or buying something else?
Beater Break-Even
How long does a cheap car need to last to beat financing?
Commute Cost Calculator
Find the true cost of your daily drive.
Gas Station Detour
Is it worth driving further for cheaper gas?
Road Trip Fuel Planner
Plan fuel stops, costs, and time for long trips.
Torque-Angle Converter
Calculate final torque from torque + angle specs.
Cylinder Overbore
Piston sizing after boring, max overbore limits.
AC Refrigerant Charge
Capacity adjustments after component replacement.
Battery CCA Calculator
Required cold cranking amps for your engine and climate.
Private Sale Price
What to list your car for based on condition and market.
Cost Per Mile (Trucking)
True operating cost for owner-operators.
Showing 23 of 23 calculators