Tire Calculator (Offset&Speed)

Easily calculate the effects of wheel and tire size changes A convenient calculation tool for anyone considering wheel upgrades, tire size changes, or fitment adjustments. Simply enter your current and new specifications to quickly compare the impact on your vehicle. -Main Features -Wheel Comparison •Calculate inner rim position changes •Calculate outer rim position changes •Calculate tread width changes -Tire Comparison •Calculate speedometer error (%) •Compare indicated speed and actual speed •Vehicle-specific speedometer error can also be included in calculations -Speedometer Error Measurement •Accurate GPS-based speed measurement -Data Storage •Save comparison records -Important Notes Measurement results may vary depending on GPS reception and environmental conditions. Use measured values as a reference only. Actual wheel and tire dimensions may vary by manufacturer and model. Calculation results are for reference purposes only. Always consult a qualified professional before making vehicle modifications. The developer assumes no responsibility for any damages or issues resulting from the use of this application. -Specifications Wheel Offset Calculator •Rim Width (in): 3" to 16" (supports 0.25" increments) •Offset (mm): -60 to +70 •Backspacing (in): 3" to 13" Speedometer Error Calculator •Tire Width (mm): 125 to 405 •Aspect Ratio (%): 20 to 90, including 82 (R) •Supports 82-series radial tires commonly used on vans and light trucks •Rim Diameter (in): 10 to 32 •Direct Tire Diameter Input: 100 to 1500 mm or 4 to 60 in •Vehicle Speedometer Error Correction (%): -20 to +20 Speedometer Error Measurement •Measurable speed range: 10 to 200 km/h or 10 to 200 mph