Does the calculator account for wheel width and offset?

No. It calculates nominal tyre geometry; wheel width, offset, centre bore, fixings and arch clearance are not assessed.

Why can actual tyre diameter differ from the calculation?

The formula uses nominal markings. Brand, model, wheel width, pressure, load and tread wear alter the real dimensions.

Kalkulator rozmiaru opon

Wprowadź dwa rozmiary opon

Obecny rozmiarRozmiar bazowy

Wymiary opony

Szerokość Profil Felga

Nowy rozmiarRozważany rozmiar

Wymiary opony

Szerokość Profil Felga

205/55 R16 means a 205 mm width, 55% aspect ratio and 16-inch rim.

Bardzo mała różnica

205/55 R16 → 225/45 R17

Zmiana średnicy+0,38 %

Porównanie wizualne

205/55 R16Obecna

225/45 R17Nowa

Najważniejsze zmiany

Prześwit+1,2 mmthe vehicle would theoretically rise

Prędkość rzeczywista100,4 km/hwhen the speedometer shows 100 km/h

Rzeczywisty dystans100,4 kmwhen the odometer records 100 km

Sprawdź inne wskazanie prędkościomierza

km/h

Szczegółowe porównanie wymiarów

Nominal theoretical dimensions calculated from the tyre marking.

Parametr	205/55 R16	225/45 R17	Różnica
Szerokość opony
Wysokość boku
Średnica felgi
Średnica zewnętrzna
Obwód teoretyczny
Obroty na kilometr

Przekłamanie licznika

Theoretical road speed if the vehicle was calibrated for the first tyre size.

Wskazanie licznika	Teoretyczna prędkość rzeczywista	Różnica

Important: this calculation isolates the effect of nominal tyre size. Factory calibration, pressure, load, tread wear and actual model dimensions also affect the reading.

Dodatkowe narzędzie

Zamienniki opon

Using 205/55 R16 find the closest nominal-diameter options for your chosen rim.

Mathematically close diameter options for rim R17. This does not confirm availability or suitability for a particular vehicle and wheel.

Rozmiar opony	Różnica średnicy	Prześwit	Speed at 100 km/h	Działanie

Jak porównać rozmiary opon?

From the sidewall marking to clear diameter and speedometer changes

Find your current size

Check the tyre sidewall or vehicle placard and enter a size such as 205/55 R16.

Enter the new size

Select the size you are considering; the standard 225/45 R17 format is used.

Compare the changes

Review sidewall height, diameter, circumference, clearance, revolutions and theoretical speedometer readings.

Check the vehicle documents

A mathematically close size is not automatically suitable. Always use sizes approved by the vehicle manufacturer.

Co oznacza rozmiar 205/55 R16?

Three main numbers describe the nominal tyre dimensions

205/55R16

205 – width

Nominal section width in millimetres.

55 – aspect ratio

The sidewall height is 55% of the width: 112.75 mm here.

R16 – construction and rim

R means radial construction and 16 is the rim diameter in inches.

Porównanie 205/55 R16 i 225/45 R17

Najczęstsze pytania o rozmiary opon

Answers about sidewall height, changing R16 to R17, speedometer difference and equivalent sizes

How do you calculate tyre sidewall height?

What is the difference between 205/55 R16 and 225/45 R17?

Which tyres can replace 205/55 R16?

Can R16 tyres be changed to R17?

How does tyre size affect the speedometer?

What tyre-diameter difference is acceptable?

How does ground clearance change?

Does the tool check wheel width and offset?

Why can actual tyre size differ from the result?

Does the calculator save entered sizes?