L305/30R21
Standard MetricFactory Specs, Physical Dimensions & Compatible Vehicle Applications
The L305/30R21 tire size features an overall diameter of 28.2 inches, a section width of 12.0 inches (305mm), and rotates 715 times per mile. It is a standard factory tire fitment on 2+ vehicle models including Mercedes-Benz GT 63 AMG.
Physical Dimensions & Specs
Overall Diameter
28.2"
716.3 mmSection Width
305 mm
12.01" wideSidewall Height
3.6"
91.4 mm (30% aspect)Revolutions / Mile
715
Circumference: 88.61"Rim Diameter
21"
Wheel sizeRecommended Rim Width
7.6" - 10.7"
Optimal rim width rangeWhere to Buy & Install L305/30R21 Tires
Looking for L305/30R21 tires? Skip hauling tires in your car—choose direct delivery to a local certified shop or doorstep delivery:
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Speedometer & Alternate Size Calculator
Testing an alternate size for your vehicle? Compare L305/30R21 against any proposed tire size below:
Visual Tire & Wheel Comparison
Speedometer Variance
| Indicated | Actual Speed | Diff |
|---|---|---|
| 20 mph | 21.0 mph | +1.0 mph |
| 30 mph | 31.5 mph | +1.5 mph |
| 45 mph | 47.2 mph | +2.2 mph |
| 60 mph | 62.9 mph | +2.9 mph |
| 75 mph | 78.6 mph | +3.6 mph |
| 90 mph | 94.4 mph | +4.4 mph |
Fender & Suspension Clearance
Flush fitment. Extends 17.7mm outwards. Check wheel arch clearance under full suspension compression.
Vehicles That Fit L305/30R21 (2+ Models)
Factory standard and optional vehicle fitments utilizing L305/30R21 tires: