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Tire size

285/30R20 tire size: dimensions explained

Factory size on the BMW M3 (G80), BMW M4 (G82). Below are the dimensions calculated from the size marking itself. Your vehicle's correct size, load index and speed rating are on the placard in the driver's door jamb; check it before buying.

MeasurementMetricImperial
Section width285 mm11.22 in
Sidewall height85.5 mm3.37 in
Overall diameter679 mm26.73 in
Wheel diameter508.0 mm20 in
Circumference2134 mm84 in
Revolutions per mile754

Calculated values: diameter = wheel + 2 × (width × aspect ratio). Real tires vary slightly by brand and model.

Reading the marking

285 is the section width in millimetres, 30 is the sidewall height as a percentage of that width, R means radial construction, and 20 is the wheel diameter in inches. A passenger (P or Euro-metric) tire and an LT tire in the same size are not interchangeable without checking load requirements.

Compare 285/30R20 with another size →

285/30R20 tires at Tire Rack

All-season

TireLoad/speedPrice per tire
Advanta HPZ-02
Ultra High Performance All-Season		XL 99Y$151.07View at Tire Rack
Goodyear Eagle Exhilarate
Ultra High Performance All-Season		XL 99Y$191.42View at Tire Rack

Summer performance

TireLoad/speedPrice per tire
Nexen N FERA SU1
Ultra High Performance Summer		XL 99Y$124.17View at Tire Rack
Sumitomo HTR Z5
Ultra High Performance Summer		XL 99Y$238.99View at Tire Rack

Winter

TireLoad/speedPrice per tire
Michelin Pilot Alpin 5
Performance Winter / Snow		XL 99V$433.42View at Tire Rack

Showing the lowest-priced in-stock options in each category from 21 285/30R20 tires in Tire Rack's feed, sorted by price only. We don't rank by commission. Match or exceed the load index and speed rating on your placard.

Affiliate links: if you buy through a Tire Rack link, RightTread may earn a commission through CJ. It doesn't change your price. Prices are Tire Rack's per-tire prices from Tire Rack's product feed as of Nov 7, 2026, 9:19 PM PT. Prices change, so confirm on Tire Rack before you buy. Disclosure

Other sizes