275/45R21 is a tire size notation. It describes geometry but does not establish the load, speed, tire class, wheel approval or fit of a particular replacement.
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How to read this size
- Nominal width: 275 mm
- Aspect ratio: 45 %
- Wheel diameter: 21.0 in
- Calculated nominal diameter: 780.9 mm
Calculated nominal diameter is an arithmetic estimate from the size code; actual product measurements vary.
Before ordering tires
Read the driver-door tire placard. Match the installed wheel, axle, tire class, load index, speed rating and any OE marking. The size alone cannot approve a replacement SKU. Tire-sidewall maximum pressure is not your vehicle’s cold inflation pressure.
Vehicles recorded with this size
| Model year and vehicle | Trim / option | Axle | Service |
|---|---|---|---|
| 2025 Ford Explorer | Platinum with Ultimate Package | unspecified | Not documented |
| 2025 Ford Explorer | ST | unspecified | Not documented |
| 2025 Ford Explorer | ST-Line with Street Pack Package | unspecified | Not documented |
| 2025 Honda Prologue | Elite | front_rear | 107H |
| 2025 Jeep Grand Cherokee | Summit 4xe with High Altitude Package | unspecified | Not documented |
| 2025 Jeep Grand Cherokee | Summit Reserve | unspecified | Not documented |
| 2025 Jeep Grand Cherokee | Summit Reserve 4xe | unspecified | Not documented |
| 2025 Jeep Grand Cherokee | Summit with High Altitude Package | unspecified | Not documented |
| 2025 Land Rover Discovery | Dynamic SE | unspecified | Not documented |
| 2025 Land Rover Discovery | Metropolitan Edition | unspecified | Not documented |
| 2025 Land Rover Discovery | S | unspecified | Not documented |
| 2025 Lincoln Aviator | Premiere AWD | front_rear | Not documented |
| 2025 Lincoln Aviator | Premiere AWD Jet Appearance | front_rear | Not documented |
| 2025 Lincoln Aviator | Premiere RWD | front_rear | Not documented |
| 2025 Lincoln Aviator | Premiere RWD Jet Appearance | front_rear | Not documented |
| 2025 Lincoln Aviator | Reserve AWD | front_rear | Not documented |
| 2025 Lincoln Aviator | Reserve RWD | front_rear | Not documented |
| 2025 Mazda CX-90 | Not documented | front_rear | 107W |
Exact product variants in research
No source-backed rows are available for this exact selection.
Explore 275/45R21 tires on Amazon
Amazon search results may mix tire classes, load and speed ratings, OE markings and package quantities. Match the full requirement on your actual vehicle before ordering.
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Search 275/45R21 tires on AmazonCompare sizes with the tire size calculator. It is an educational geometry comparison, not a fitment ruling.
Sources and scope
- Goodyear — 2025 Ford Explorer: version/option and tire size (checked 2026-11-01)
- American Honda — 2025 Honda Prologue Specifications & Features (checked 2026-11-01)
- Mazda USA — 2025 cx-90 Owner Manual — Vehicle Specification (checked 2026-11-01)
- Goodyear US — Find 2025 Jeep Grand-Cherokee Tires (checked 2026-11-01)
- Goodyear — 2025 Lincoln Aviator tire size by trim (checked 2026-11-01)
- Goodyear — Find 2025 Land Rover Discovery Tires | Goodyear (checked 2026-11-01)
Research checked November 2, 2026. A source-observed size is not final product fitment. Confirm the actual vehicle and current manufacturer guidance.