Tire Size Comparison Calculator
Compare different tire sizes to understand their effects on diameter, circumference, revolutions per mile, and speedometer accuracy.
Step 1: Original Tire Size
Understanding Tire Size
Tire size is expressed as width/aspect ratioRim diameter (e.g., 225/45R17). Width is in millimeters, aspect ratio is the height as percentage of width, and rim diameter is in inches.
Step 2: New Tire Size
Important Considerations
Changing tire size can affect speedometer accuracy, vehicle handling, fuel economy, and clearance. Always consult with a professional before changing tire sizes.
Original
225/45R17
→
New
235/40R18
Tire Size Comparison Results
Summary
Detailed Comparison
Effects & Impact
Overall Diameter Difference
+0.3%
Speedometer reads 0.2 mph slower at 60 mph
Diameter Difference
+2.1 mm
Circumference Difference
+6.6 mm
Revs per Mile
-1.2
Speedometer Difference
-0.3%
Detailed Tire Comparison
| Parameter | Original Tire | New Tire | Difference | Change % |
|---|
Effects of Tire Size Change
Key Impacts
What Changes When You Alter Tire Size
• Speedometer accuracy
• Odometer readings
• Acceleration and braking
• Fuel economy
• Ride comfort
• Clearance and handling
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