Tire Size Calculator to inches
Here’s a comprehensive guide to converting tire sizes from metric to inches, including a conversion table and key information you need to know:
Understanding Tire Size Conversion
Tire sizes are typically expressed in two formats: metric and inches. Converting between these formats is essential for comparing different tire options and ensuring proper fitment for your vehicle.
Metric to Inch Conversion Table
Here’s a table showing common metric tire sizes converted to inches:
| Metric Size | Width (inches) | Overall Diameter (inches) |
|---|---|---|
| 215/70R15 | 8.46 | 27.72 |
| 265/75R16 | 10.43 | 31.65 |
| 315/70R17 | 12.40 | 34.41 |
| 255/60R18 | 10.04 | 29.53 |
| 245/70R19.5 | 9.65 | 33.07 |
Key Components of Tire Size
To understand tire size conversion, it’s important to know what each part of the tire size designation means:
- Section Width: The first number in a metric tire size (e.g., 215 in 215/70R15) represents the tire’s width in millimeters.
- Aspect Ratio: The second number (e.g., 70 in 215/70R15) is the aspect ratio, which is the sidewall height as a percentage of the width.
- Rim Diameter: The last number (e.g., 15 in 215/70R15) indicates the rim diameter in inches.
Conversion Process
To convert a metric tire size to inches:
- Width Conversion: Divide the section width by 25.4 to convert from millimeters to inches1.
- Sidewall Height Calculation: Multiply the width by the aspect ratio percentage to get the sidewall height1.
- Overall Diameter Calculation: Use the formula: (2 × sidewall height) + rim diameter1.
Important Considerations
- Accuracy: Tire size conversions are approximate, as actual dimensions can vary slightly between manufacturers4.
- Speedometer Impact: Changing tire sizes can affect your vehicle’s speedometer reading and overall performance2.
- Vehicle Compatibility: Always ensure that the converted tire size is compatible with your vehicle’s specifications and wheel wells4.
- Load Capacity: Different tire sizes may have different load capacities, which is crucial for vehicle safety3.
By understanding these conversion principles and using the provided table, you can easily compare different tire sizes and make informed decisions when selecting tires for your vehicle. Remember to consult your vehicle’s manual or a professional if you’re unsure about tire fitment or compatibility.