What 195/50R16 means
The inputs are 195 mm nominal section width, a 50-percent aspect ratio, and a 16-inch nominal rim diameter. The R identifies radial construction. The width is not a wheel-width measurement, and the rim number is not the outside diameter of the tire.
Nominal sidewall height is 195 × 50 ÷ 100 = 97.5 mm. Adding two sidewalls to the 406.4 mm rim gives 601.4 mm (23.68 in) of nominal outside diameter.
A calculated reference
At a 50-percent ratio, the two nominal sidewalls together equal the 195 mm width. The diameter formula therefore simplifies to 406.4 + 195 = 601.4 mm for this marking. That simplification applies because the ratio is 50 percent.
Using a perfect-circle model, circumference is 1889.35 mm, equivalent to 529.28 revolutions per kilometer or 851.8 per mile. These are derived from unrounded diameter; actual rolling circumference also depends on the product and operating conditions.
Source and scope
General Tire’s AltiMAX RT45 source includes 195/50R16, article 15576110000. It was checked on October 27, 2026. That record verifies the published marking used here; it does not turn these calculated dimensions into that product’s measured specification or establish availability.
Use the exact product and vehicle requirements for load and speed ratings, permitted rim dimensions, inflation and clearance. Nominal geometry alone cannot verify fitment, braking behavior, handling or safety.
Sources and further reading
- AltiMAX RT45 — General Tire
- Tire Markings Explained — Michelin
- Tire glossary — Michelin