Let's say OE tires are 205/65 r15. The quick break down...205 (tread width, in millimeters), 65 (aspect ratio...205* 0.65= 133.25 mm...sidewall height), and r15 is rim diameter (don't know why they use "r"). So the total tire height, in inches is 15+ 133.25*(.03997[conversion factor from mm to inches])*2= 25.49 inches<br><br>Yeah, you can do all that math, the easier way is to pick up this pattern...<br><br>Say you want wider wheels, 215/60 r15. Say you want 16" rims, 205/60 r16.<br><br>So basically for every increment of tread width (215, 225, 235,...)or rim diamter (16", 17",...) you decrease the aspect ratio by 5. If you do both, increase the tread width and rim diamter, decrease the aspect ratio by 10. It works in reverse also.<br><br>205/65 r15 (25.49")<br><br>205/60 r16 Solara Sport Package& Camry XLE V6(25.69",+0.7%)<br><br>215/55 r16 TRD Camry 6cyl (25.31", -0.7%)<br><br>tan

Hello Thisistan : Thanks for the math conversion If i did well my rims 15x6 and tire 205/65/15 , would be the same heigh if I put 225/55/15, right?

the 225/55 will be 0.75 inches smaller, or 2.9 percent smaller (which is still safe). But (I don't know the answer)will a 225mm tire fit a 6" rim?<br><br>tan