CarSpecsHQ

175/65R15 vs 205/50R16

205/50R16 is a safe swap for 175/65R15 by the usual ±3% rule: the diameter differs by +0.48%.

15" → 16"
175/65R15 23.96" · 205/50R16 24.07" · drawn to scale

Side by side

175/65R15205/50R16Difference
Overall diameter23.96"24.07"+0.11" (+0.48%)
Section width175 mm205 mm+30 mm
Sidewall4.48"4.04"-0.44"
Rim15"16"+1"
Circumference75.3"75.6"+0.4"
Revs per mile842838-4
Ride height——+0.06"
Speedometer reads 60 mph60.060.3+0.3 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.3 mph

With 205/50R16 on a car calibrated for 175/65R15, the speedometer reads 59.7 mph when you're really doing 60, and the odometer under-counts by 0.5%.

Speedo showsActual speed
30 mph30.1 mph
45 mph45.2 mph
60 mph60.3 mph
70 mph70.3 mph
80 mph80.4 mph

Other sizes close to 175/65R15

Questions

Can I replace 175/65R15 with 205/50R16?

205/50R16 is a safe swap for 175/65R15 by the usual ±3% rule: the diameter differs by +0.48%.

What's the difference between 175/65R15 and 205/50R16?

205/50R16 is 0.11" taller and 30 mm wider; the sidewall is -0.44". At an indicated 60 mph you'd actually be doing 60.3 mph.

Will 205/50R16 fit on 175/65R15 wheels?

No — 175/65R15 needs a 15" wheel and 205/50R16 a 16" wheel. This is a plus/minus-size swap that changes wheels too.