About WheelDeck

WheelDeck is a free collection of automotive utilities focused on tire sizing. Our tools are designed to be fast, accurate, and readable in real-world shop conditions — bright sunlight, dirty screens, gloves on.

What we offer

• Tire Size Calculator — enter width, profile, and rim diameter to get overall diameter, sidewall height, circumference, and revolutions per mile or km with a proportional diagram.
• Tire Size Comparison — compare two tire sizes side by side, see the diameter difference, and check how much the speedometer will be off with a different size.
• How to Read Tire Size — illustrated guide explaining what every part of a tire size code means, with FAQ.

How calculations work

All math runs entirely in your browser — no server, no tracking of your inputs. The calculations follow standard formulas used in the automotive industry:

• Sidewall height = Section width × (Aspect ratio / 100)
• Overall diameter = (Sidewall height × 2) + (Rim diameter × 25.4 mm/in)
• Circumference = π × Overall diameter
• Revolutions per mile = 1,609,344 mm ÷ Circumference
• Revolutions per km = 1,000,000 mm ÷ Circumference

Results are accurate for standard passenger car and light truck tires with standard size codes (e.g., 205/55R16). Load index, speed rating, and other markings on the sidewall are not part of the size calculation.

Units

WheelDeck detects your location on first visit and defaults to inches for US users and millimeters for everyone else. You can switch at any time using the in/mm toggle — your choice is saved in your browser for future visits.

Contact

Questions, corrections, or suggestions? Email us at gwalkmanvova@gmail.com.

Privacy

We don't track tire sizes you enter. See our Privacy Policy for full details.