245/40R21
Standard MetricFactory Specs, Physical Dimensions & Compatible Vehicle Applications
The 245/40R21 tire size features an overall diameter of 28.72 inches, a section width of 9.6 inches (245mm), and rotates 702 times per mile. It is a standard factory tire fitment on 20+ vehicle models including Genesis G90.
Physical Dimensions & Specs
Overall Diameter
28.72"
729.5 mmSection Width
245 mm
9.65" wideSidewall Height
3.86"
98.0 mm (40% aspect)Revolutions / Mile
702
Circumference: 90.22"Rim Diameter
21"
Wheel sizeRecommended Rim Width
6.1" - 8.6"
Optimal rim width rangeWhere to Buy & Install 245/40R21 Tires
Looking for 245/40R21 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 245/40R21 against any proposed tire size below:
Visual Tire & Wheel Comparison
Speedometer Variance
| Indicated | Actual Speed | Diff |
|---|---|---|
| 20 mph | 20.6 mph | +0.6 mph |
| 30 mph | 30.9 mph | +0.9 mph |
| 45 mph | 46.3 mph | +1.3 mph |
| 60 mph | 61.8 mph | +1.8 mph |
| 75 mph | 77.2 mph | +2.2 mph |
| 90 mph | 92.7 mph | +2.7 mph |
Fender & Suspension Clearance
Flush fitment. Extends 17.7mm outwards. Check wheel arch clearance under full suspension compression.
Vehicles That Fit 245/40R21 (20+ Models)
Factory standard and optional vehicle fitments utilizing 245/40R21 tires: