TireSizesFinder

295/35R21 vs 235/45R21

235/45R21 is 0.20 in (5.0 mm) taller than 295/35R21, a +0.68% diameter difference. With the speedometer set for 295/35R21, an indicated 60 mph is 60.4 mph on 235/45R21.

Is this a safe swap?

Diameter difference +0.68%: under 1%

By overall diameter alone, 235/45R21 is a near match for 295/35R21; the speedometer changes by less than 1%. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 295/35R21 (29.13 in) vs 235/45R21 (29.33 in)295/35R2129.13 in × 11.61 in235/45R2129.33 in × 9.25 in
Side profile and tread width, drawn to the same scale.
295/35R21 vs 235/45R21 differences
Measurement295/35R21235/45R21Difference% diff
Overall diameter29.13 in (739.9 mm)29.33 in (744.9 mm)+0.20 in (+5.0 mm)+0.68%
Sidewall height4.06 in (103.3 mm)4.16 in (105.8 mm)+0.10 in (+2.5 mm)+2.42%
Section width11.61 in (295.0 mm)9.25 in (235.0 mm)−2.36 in (−60.0 mm)−20.34%
Circumference91.51 in (2,324.5 mm)92.13 in (2,340.2 mm)+0.62 in (+15.7 mm)+0.68%
Revolutions per mile692688−5−0.67%
True speed with the speedometer calibrated for 295/35R21
IndicatedActual on 295/35R21Actual on 235/45R21Difference
30 mph30.0 mph30.2 mph+0.2 mph
60 mph60.0 mph60.4 mph+0.4 mph
75 mph75.0 mph75.5 mph+0.5 mph

Ride-height change: 235/45R21 raises the vehicle by 0.10 in (2.5 mm) at the axle (half the +5.0 mm diameter difference).

235/45R21 is 0.20 in taller than 295/35R21 and 60 mm narrower, a 0.68% difference in overall diameter.

With the speedometer calibrated for 295/35R21, an indicated 60 mph is actually 60.4 mph on 235/45R21, and revolutions per mile change from 692 to 688.

Both sizes mount on 21-inch wheels.

Size pages

Other comparisons with 295/35R21

Other comparisons with 235/45R21

Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.