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Tire size

245/45R20 tire size: dimensions explained

Factory size on the Porsche Taycan, Ford Mustang Mach-E GT. 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 width245 mm9.65 in
Sidewall height110.3 mm4.34 in
Overall diameter728.5 mm28.68 in
Wheel diameter508.0 mm20 in
Circumference2289 mm90.1 in
Revolutions per mile703

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

Reading the marking

245 is the section width in millimetres, 45 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 245/45R20 with another size →

245/45R20 tires at Tire Rack

All-season

TireLoad/speedPrice per tire
Radar Dimax AS-8
Grand Touring All-Season		XL 103W$116.02View at Tire Rack
Riken Raptor VR
Grand Touring All-Season		99V$136.03View at Tire Rack

Highway / touring

TireLoad/speedPrice per tire
Yokohama Geolandar X-CV
Crossover/SUV Touring All-Season		XL 103W$198.19View at Tire Rack
Kumho Crugen GT Pro
Crossover/SUV Touring All-Season		XL 103W$227.51View at Tire Rack

All-terrain

TireLoad/speedPrice per tire
Nitto Nomad Grappler
On-Road All-Terrain		XL 103H$267.00View at Tire Rack

Summer performance

TireLoad/speedPrice per tire
Firestone Firehawk Indy 500
Ultra High Performance Summer		XL 103W$146.86View at Tire Rack
Kumho Ecsta Sport
Ultra High Performance Summer		XL 103Y$224.64View at Tire Rack

Winter

TireLoad/speedPrice per tire
Vredestein Wintrac Pro+
Performance Winter / Snow		XL 103V$237.93View at Tire Rack
Michelin X-Ice Snow SUV
Light Truck/SUV Studless Ice & Snow Truck		XL 103H$240.98View at Tire Rack

Showing the lowest-priced in-stock options in each category from 96 245/45R20 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