A familiar situation
Vergleichen Sie nominelle Reifendurchmesser, etwa beim Wechsel auf eine andere Reifengröße.
How to use this calculator
- Enter tire width, aspect ratio, wheel diameter.
- Select Calculate to see the answer and its breakdown.
- Keep a scenario, change an input and compare the results.
Use consistent units and check the assumptions below before applying the result.
How tire size is calculated
Estimate tire sidewall height, overall diameter, circumference, and speedometer difference from a metric tire code such as 205/55R16. It assumes the nominal width and aspect ratio; actual dimensions vary by model, rim width, pressure, wear, and load. A 205/55R16 tire has a nominal sidewall height of 112.75 mm. The calculation validates each input and keeps its stated units explicit. No. Check manufacturer fitment, clearance, load index, and speed rating. This is an estimate for the stated assumptions; confirm measurements and any applicable professional or local standards before relying on it.
diameter = 2 × width × aspect ratio + rim diameterA 205/55R16 tire has a nominal sidewall height of 112.75 mm.
Assumptions & useful context
The result depends on the values you enter and the method described above. Displayed numbers may be rounded; calculations use the unrounded values. Check that this model matches your situation before relying on it.
Frequently asked questions
Does it verify wheel fitment?
No. Check manufacturer fitment, clearance, load index, and speed rating.
Why can the real diameter differ?
The code gives nominal dimensions; casing design and operating conditions affect measured size.