πŸ›ž Tire Size Converter

Convert tire sizes between metric and imperial, calculate sidewall height, circumference, and analyze performance impact.

πŸ“ Metric Format

Example: 225/60R16

πŸ‡ΊπŸ‡Έ Imperial Format

Example: 31x10.5R15

πŸ›ž Tire Visualization

16"
225mm
135mm
Sidewall Height
135
mm / 5.3 in
Overall Diameter
28.6
inches / 726mm
Circumference
89.9
inches / 2283mm
Revolutions/Mile
705
rev/mile

⚑ Performance Impact Analysis

🏁
0%
Speedometer Error
β›½
Standard
Fuel Economy
🎯
Balanced
Handling
πŸ›‘οΈ
Standard
Ride Comfort
πŸ›ž Common Tire Size Examples
πŸš—
Compact Car
195/65R15
Overall: 25.0" | Width: 7.7"
Economy cars, city driving
πŸš™
Mid-size Sedan
225/60R16
Overall: 28.6" | Width: 8.9"
Family cars, touring
🏎️
Sport Sedan
245/45R18
Overall: 26.7" | Width: 9.6"
Performance cars, low profile
🚚
Pickup Truck
265/70R17
Overall: 31.6" | Width: 10.4"
Light trucks, hauling
πŸ”οΈ
Off-Road SUV
285/75R16
Overall: 32.8" | Width: 11.2"
4WD, off-road adventures
🏁
Super Sports
315/35R20
Overall: 28.7" | Width: 12.4"
Supercars, track use
🚐
Crossover SUV
215/55R17
Overall: 26.3" | Width: 8.5"
Urban SUVs, family use
πŸš›
Commercial Van
235/85R16
Overall: 31.7" | Width: 9.3"
Cargo vans, commercial
πŸ“Š Tire Size Comparison Chart
Metric Size Imperial Equivalent Overall Diameter Section Width Sidewall Height Vehicle Type
155/80R13 24.6x6.1R13 24.6" (625mm) 6.1" (155mm) 4.9" (124mm) Small car
185/65R15 25.5x7.3R15 25.5" (648mm) 7.3" (185mm) 4.7" (120mm) Compact car
205/55R16 24.9x8.1R16 24.9" (632mm) 8.1" (205mm) 4.5" (113mm) Mid-size car
225/60R16 28.6x8.9R16 28.6" (726mm) 8.9" (225mm) 5.3" (135mm) Full-size sedan
235/65R17 29.0x9.3R17 29.0" (737mm) 9.3" (235mm) 6.0" (153mm) SUV/Crossover
245/75R16 30.5x9.6R16 30.5" (775mm) 9.6" (245mm) 7.2" (184mm) Light truck
265/70R17 31.6x10.4R17 31.6" (803mm) 10.4" (265mm) 7.3" (186mm) Pickup truck
285/70R17 32.7x11.2R17 32.7" (831mm) 11.2" (285mm) 7.9" (200mm) Large SUV
315/70R17 34.4x12.4R17 34.4" (874mm) 12.4" (315mm) 8.7" (221mm) Off-road truck
37x12.5R17 315/70R17 37.0" (940mm) 12.5" (318mm) 10.25" (260mm) Extreme off-road

πŸ“ Size Measurement Guide

  • Width: Tire section width from sidewall to sidewall
  • Aspect Ratio: Sidewall height as percentage of width
  • Rim Diameter: Wheel diameter in inches
  • Overall Diameter: Total tire diameter (rim + 2Γ— sidewall)
  • Circumference: Distance traveled in one complete rotation
πŸ“š Tire Size Guide

🎯 Understanding Tire Size Markings

Tire sizes are marked in specific formats that contain crucial information about dimensions and specifications.

πŸ“ Metric Format: P225/60R16 98H

  • P: Passenger car designation
  • 225: Section width in millimeters
  • 60: Aspect ratio (sidewall height Γ· width Γ— 100)
  • R: Radial construction
  • 16: Rim diameter in inches
  • 98: Load index
  • H: Speed rating

πŸ‡ΊπŸ‡Έ Imperial Format: 31x10.5R15LT

  • 31: Overall diameter in inches
  • 10.5: Section width in inches
  • R: Radial construction
  • 15: Rim diameter in inches
  • LT: Light truck designation

πŸ”’ Key Calculations

  • Sidewall Height: (Width Γ— Aspect Ratio) Γ· 100
  • Overall Diameter: (2 Γ— Sidewall Height) + Rim Diameter
  • Circumference: Overall Diameter Γ— Ο€
  • Revolutions per Mile: 63,360 Γ· Circumference
  • Speed Difference: (New Diameter Γ· Old Diameter - 1) Γ— 100%

⚠️ Plus Sizing Guidelines

  • Plus 1: +1" rim, -1" sidewall (maintain diameter)
  • Plus 2: +2" rim, -2" sidewall (maintain diameter)
  • Maximum difference: Keep within 3% of original diameter
  • Load capacity: Must meet or exceed original tire rating
  • Speedometer accuracy: Larger = reads slower, smaller = reads faster

🎯 Performance Impact of Size Changes

  • Wider tires: Better grip, higher fuel consumption
  • Lower profile: Better handling, harsher ride
  • Larger diameter: Better appearance, increased cost
  • Taller sidewall: More comfortable, less precise handling
  • Heavier tires: Slower acceleration, more brake wear

πŸ”§ Replacement Guidelines

  • Diameter tolerance: Β±3% of original overall diameter
  • Load index: Equal or higher than original
  • Speed rating: Equal or higher than original
  • Clearance check: Ensure no rubbing at full lock/compression
  • TPMS compatibility: Consider sensor compatibility

🏁 Speed Rating Chart

  • S: 112 mph (180 km/h)
  • T: 118 mph (190 km/h)
  • H: 130 mph (210 km/h)
  • V: 149 mph (240 km/h)
  • W: 168 mph (270 km/h)
  • Y: 186 mph (300 km/h)
  • Z: Over 149 mph (240+ km/h)

πŸ’‘ Using This Calculator Effectively

  • Enter any of the three metric values to calculate imperial equivalent
  • Use the imperial section for flotation or LT tire sizes
  • Check the performance impact section for replacement effects
  • Compare different sizes using the examples section
  • Always verify clearance and load capacity before purchasing
  • Consider your driving style and vehicle use when selecting sizes