🚗 Tire Size Calculator
Compare tire sizes, calculate diameter differences, and find equivalent tire sizes. Determine speedometer accuracy, clearance requirements, and performance impacts when changing tire sizes.
📏 Diameter Difference
+0.5"
Overall Change
📊 Tire Specifications
🚗 Performance Impact
⚠️ Compatibility Check
📏 Common Tire Sizes
| Vehicle Type |
Common Sizes |
Diameter Range |
| 🚗 Compact Car |
185/65R15, 195/60R16 |
24-26" |
| 🚙 Mid-size Car |
225/60R16, 235/55R17 |
26-28" |
| 🚙 SUV |
235/65R17, 255/60R18 |
28-32" |
| 🚚 Pickup Truck |
265/70R17, 285/65R18 |
31-35" |
| 🏎️ Sports Car |
245/40R18, 275/35R19 |
25-27" |
🚗 Understanding Tire Sizes
Tire size notation follows a standardized format that provides crucial information about the tire's dimensions and capabilities. Understanding these numbers helps you make informed decisions about tire replacements and upgrades.
📏 Tire Size Format Explained
| Component |
Example |
Meaning |
Impact |
| 📏 Width |
225 |
Tire width in millimeters |
Contact patch, handling |
| 📊 Aspect Ratio |
60 |
Sidewall height as % of width |
Ride comfort, handling |
| 🏗️ Construction |
R |
Radial construction |
Durability, performance |
| ⭕ Rim Diameter |
16 |
Wheel diameter in inches |
Brake clearance, aesthetics |
📊 Size Change Effects
| Change Type |
Effect on Performance |
Pros |
Cons |
| 📏 Wider Tire |
Increased contact patch |
Better grip, cornering |
Higher cost, fuel consumption |
| 📊 Lower Profile |
Reduced sidewall flex |
Better handling, response |
Harsher ride, road noise |
| ⭕ Larger Rim |
More brake clearance |
Better braking, appearance |
Higher cost, pothole damage |
| 📈 Plus Sizing |
Maintained overall diameter |
Performance + accuracy |
Cost, comfort trade-offs |
⚠️ Compatibility Guidelines
| Measurement |
Acceptable Range |
Ideal Range |
Consequences if Exceeded |
| 📏 Overall Diameter |
±3% (±0.75") |
±1% (±0.25") |
Speedometer error, clearance issues |
| 📊 Width Increase |
+30mm max |
+20mm max |
Rubbing, reduced fuel economy |
| ⭕ Rim Size Change |
±2 inches |
±1 inch |
Ride quality, cost impact |
| ⚖️ Load Rating |
Equal or higher |
Match original |
Safety risk, tire failure |
🏎️ Plus Sizing Guide
| Plus Size |
Rim Change |
Typical Application |
Benefits |
| Plus 0 |
Same size |
OEM replacement |
Exact match, no changes |
| Plus 1 |
+1 inch |
Mild performance upgrade |
Better handling, appearance |
| Plus 2 |
+2 inches |
Performance enhancement |
Significant handling improvement |
| Plus 3 |
+3 inches |
Maximum performance |
Track-level handling |
💰 Cost Considerations
| Size Category |
Price Range |
Replacement Frequency |
Total Cost Impact |
| 🚗 Standard (15-16") |
$80-200 each |
60,000-80,000 miles |
Low |
| 🚙 Mid-size (17-18") |
$120-300 each |
50,000-70,000 miles |
Medium |
| 🏎️ Performance (19-20") |
$200-500 each |
30,000-50,000 miles |
High |
| 🏁 Ultra-High (21"+) |
$300-800+ each |
20,000-40,000 miles |
Very High |
💡 Selection Tips
- 📏 Maintain Diameter: Keep overall diameter within ±3% for accuracy
- 🚗 Consider Usage: Daily driving vs performance needs
- 💰 Budget Impact: Larger sizes cost more to buy and replace
- 🌡️ Climate Factors: Winter tires may need different sizing
- ⚖️ Load Rating: Never go below original load capacity
- 🏁 Speed Rating: Match or exceed original rating
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