Fitment reports816 pairs
Size against size,
Size against size,
with a verdict
Every pair here is one a driver could plausibly be choosing between — same rim within 6% on diameter, or one rim up within 3%. Comparisons nobody would ever make do not get a page.
Start with any size
Or open a size page and take its alternatives table — every row there links to the full report.
165/60R15 vs 195/50R15−0.52% · within tolerance165/60R16 vs 195/50R16−0.50% · within tolerance165/65R15 vs 195/55R15+0.00% · within tolerance165/65R16 vs 195/55R16+0.00% · within tolerance165/70R15 vs 195/60R15+0.49% · within tolerance165/70R16 vs 195/60R16+0.47% · within tolerance175/45R16 vs 195/40R16−0.27% · within tolerance175/45R17 vs 195/40R17−0.25% · within tolerance175/45R18 vs 195/40R18−0.24% · within tolerance175/45R19 vs 195/40R19−0.23% · within tolerance175/45R20 vs 195/40R20−0.23% · within tolerance175/50R15 vs 195/45R15+0.09% · within tolerance175/50R16 vs 195/45R16+0.09% · within tolerance175/50R17 vs 195/45R17+0.08% · within tolerance175/50R18 vs 195/45R18+0.08% · within tolerance175/50R19 vs 195/45R19+0.08% · within tolerance175/50R20 vs 195/45R20+0.07% · within tolerance175/55R15 vs 195/50R15+0.44% · within tolerance175/55R16 vs 195/50R16+0.42% · within tolerance175/55R17 vs 195/50R17+0.40% · within tolerance175/55R18 vs 195/50R18+0.38% · within tolerance175/55R19 vs 195/50R19+0.37% · within tolerance175/55R20 vs 195/50R20+0.36% · within tolerance175/60R15 vs 195/55R15+0.76% · within tolerance175/60R16 vs 195/55R16+0.73% · within tolerance175/60R17 vs 195/55R17+0.70% · within tolerance175/60R18 vs 195/55R18+0.67% · within tolerance175/60R19 vs 195/55R19+0.65% · within tolerance175/60R20 vs 195/55R20+0.63% · within tolerance175/65R15 vs 205/55R15−0.33% · within tolerance175/65R16 vs 205/55R16−0.32% · within tolerance175/65R17 vs 195/60R17+0.99% · within tolerance175/65R17 vs 205/55R17−0.30% · within tolerance175/65R18 vs 195/60R18+0.95% · within tolerance175/65R18 vs 205/55R18−0.29% · within tolerance175/65R19 vs 195/60R19+0.92% · within tolerance175/65R19 vs 205/55R19−0.28% · within tolerance175/70R15 vs 205/60R15+0.16% · within tolerance175/70R16 vs 205/60R16+0.15% · within tolerance175/70R17 vs 205/60R17+0.15% · within tolerance175/75R17 vs 205/65R17+0.58% · within tolerance185/40R16 vs 195/40R16+1.44% · within tolerance185/40R17 vs 195/40R17+1.38% · within tolerance185/40R18 vs 195/40R18+1.32% · within tolerance185/40R19 vs 195/40R19+1.27% · within tolerance185/40R20 vs 195/40R20+1.22% · within tolerance185/45R15 vs 195/45R15+1.64% · within tolerance185/45R16 vs 195/40R16−1.83% · within tolerance185/45R16 vs 195/45R16+1.57% · within tolerance185/45R16 vs 205/40R16−0.44% · within tolerance185/45R17 vs 195/45R17+1.50% · within tolerance185/45R17 vs 205/40R17−0.42% · within tolerance185/45R18 vs 195/45R18+1.44% · within tolerance185/45R18 vs 205/40R18−0.40% · within tolerance185/45R19 vs 195/45R19+1.39% · within tolerance185/45R19 vs 205/40R19−0.39% · within tolerance185/45R20 vs 195/45R20+1.33% · within tolerance185/45R20 vs 205/40R20−0.37% · within tolerance185/50R15 vs 195/45R15−1.68% · within tolerance185/50R15 vs 205/45R15−0.09% · within tolerance
What a comparison here actually contains
- A verdict against the ±3% rolling-diameter convention, on a rail, so you can see how much room is left.
- Both tyres drawn concentrically at one scale, with the tolerance band shaded around the original.
- Speedometer error at every speed from 50 to 110, in both km/h and mph, with the UN ECE R39 position stated.
- The full side-by-side: sidewall, section width, circumference, revolutions per kilometre, ride height and odometer drift.
- An explicit list of what geometry cannot tell you, which on this subject is most of the risk.