L305/30R21
Standard MetricFactory Specs, Physical Dimensions & Compatible Vehicle Applications
Factory Spec Overview
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 rangeSpeedometer & Alternate Size Calculator
Testing an alternate size for your vehicle? Compare L305/30R21 against any proposed tire size below:
Popular Comparisons:
Tire 1 (Stock / Base)305/30R21
Overall Height:28.2"
Sidewall:3.6"
Revs/Mile:715
Tire 2 (New / Compare)245/60R18
Overall Height:29.6"
Sidewall:5.8"
Revs/Mile:682
Visual Tire & Wheel Comparison
Speedometer Variance
+4.9%At 60 mph reading, actual speed is 62.9 mph
| 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
Fitment Status: MODERATE RISK
Flush fitment. Extends 17.7mm outwards. Check wheel arch clearance under full suspension compression.
Inner Strut Space:7.7mm LESS clearance
Outer Fender Push:Extends 17.7mm further out
Ride Height Delta:+0.69" ground clearance
Vehicles That Fit L305/30R21 (2+ Models)
Factory standard and optional vehicle fitments utilizing L305/30R21 tires: