265/40R21
Standard MetricFactory Specs, Physical Dimensions & Compatible Vehicle Applications
The 265/40R21 tire size features an overall diameter of 29.35 inches, a section width of 10.4 inches (265mm), and rotates 687 times per mile. It is a standard factory tire fitment on 21+ vehicle models including BMW X3 M, BMW X4 M.
Physical Dimensions & Specs
Overall Diameter
29.35"
745.5 mmSection Width
265 mm
10.43" wideSidewall Height
4.17"
105.9 mm (40% aspect)Revolutions / Mile
687
Circumference: 92.19"Rim Diameter
21"
Wheel sizeRecommended Rim Width
6.6" - 9.3"
Optimal rim width rangeWhere to Buy & Install 265/40R21 Tires
Looking for 265/40R21 tires? Skip hauling tires in your car—choose direct delivery to a local certified shop or doorstep delivery:
Tire Rack
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Amazon Automotive
Fast doorstep shipping for DIYers or bringing to your own shop.
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Speedometer & Alternate Size Calculator
Testing an alternate size for your vehicle? Compare 265/40R21 against any proposed tire size below:
Visual Tire & Wheel Comparison
Speedometer Variance
| Indicated | Actual Speed | Diff |
|---|---|---|
| 20 mph | 20.2 mph | +0.2 mph |
| 30 mph | 30.2 mph | +0.2 mph |
| 45 mph | 45.4 mph | +0.4 mph |
| 60 mph | 60.5 mph | +0.5 mph |
| 75 mph | 75.6 mph | +0.6 mph |
| 90 mph | 90.7 mph | +0.7 mph |
Fender & Suspension Clearance
Flush fitment. Extends 17.7mm outwards. Check wheel arch clearance under full suspension compression.
Vehicles That Fit 265/40R21 (21+ Models)
Factory standard and optional vehicle fitments utilizing 265/40R21 tires: