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4x4 tools & calculators
Free calculators for tire size, gearing, towing and off-road angles. Everything runs in your browser; nothing you type is stored.
Photo: Bradley Dunn / Unsplash
Tire Size Calculator
Compare two sizes: diameter, speedometer error and clearance gain.
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Gear Ratio Calculator
Find the axle ratio that restores performance after bigger tires.
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Towing & Payload Calculator
Check payload, tongue weight, GVWR and GCWR before you hook up.
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Off-Road Angle Calculator
Approach, breakover and departure angles from your own measurements.
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Truck Finder
Six questions, then a ranked shortlist of 2026 4x4 pickups for you.
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Compare Trucks
Put up to three 2026 trucks side by side, spec by spec.
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Which tool do I need?
- Going to bigger tires? Start with the tire size calculator to see the real diameter, speedometer error and clearance gain. Then use the gear ratio calculator to see whether you should regear.
- Hooking up a trailer or loading a camper? The towing and payload calculator checks every rating on your door-jamb labels at once.
- Planning a lift or new bumpers? The off-road angle calculator shows what the changes do to approach, breakover and departure.
- Shopping? The Truck Finder builds a shortlist, and Compare puts them side by side.