255/45 R21 Tyres in Park Royal
255 mm wide, 45% profile, for a 21-inch wheel. Fitted at our NW10 workshop, with live prices online.
255/45 R21 is a 21-inch tyre, 255 mm wide, with a sidewall 114.8 mm tall (45% of the width). We fit 255/45 R21 tyres at our Park Royal garage in NW10, with balancing, a new valve and disposal of the old tyre included. The price depends on the brand: see live prices for 255/45 R21. It is fitted to cars such as the Porsche Macan Electric.
What 255/45 R21 means
- 255: the tyre is 255 mm wide, measured across the sidewalls.
- 45: the sidewall height is 45% of the width, so 255 × 45% = 114.8 mm.
- R: radial construction. A ZR in the same place is the same size with a speed marking for over 240 km/h.
- 21: it fits a 21-inch wheel. Overall diameter is 21 × 25.4 mm plus two sidewalls: 762.9 mm.
The load index and speed rating follow the size on the sidewall (for example 91V). Replace like for like or higher, as your handbook states.
Cars that use 255/45 R21
Manufacturer and tyre-maker fitment listings give 255/45 R21 for these models, usually as one of several wheel options. The size on your own tyres, or on the placard in the door frame, is the one to match.
| Make | Model | Generation |
|---|---|---|
| Porsche | Macan Electric | XAB (2024-) |
What to look for in a 255/45 R21 tyre
- Low profile, less cushion. A 114.8 mm sidewall on a 21-inch wheel leaves little to absorb a pothole or a kerb, so check for bulges and rim damage after a hard hit, and have the wheel alignment checked if the steering pulls or the new tyres wear on one edge.
- Check the load index. Many of the SUVs, crossovers and vans on this size are heavy, and some are fitted with reinforced (XL) tyres. Match or beat the load index on the tyres you are replacing.
- Electric cars. This size is common on EVs, which are heavier than a petrol car of the same size. Keep at least the original load index (some EVs use HL or XL tyres), and check the tread more often: the extra weight and instant torque can wear tyres faster.
- Winter or all-season. If you want winter or all-season tyres in 255/45 R21, the live list shows what is made in this size today; not every pattern is made in every size.
255/45 R21 tyres by price band
These are the brands we fit, by price band. Which of them make 255/45 R21, and at what price today, is on the live price list.
- Premium: Continental, Pirelli, Hankook, Yokohama, Bridgestone, Dunlop, Goodyear, Michelin
- Mid-range: Avon, Nankang, Roadstone, Kumho
- Budget: Accelera, Linglong
Prices for 255/45 R21 depend on the brand — see live fitted prices for 255/45 R21.
Book online, call 020 3886 2355 or WhatsApp 07476 586 589. We fit at Unit 4 Unimix House, Abbey Road, Park Royal, London, NW10 7TR, balancing and a new valve included.
Sizes next to 255/45 R21
Same 21-inch rim, one step wider, narrower, taller or lower.
Sizes with a similar overall diameter
These sizes are within 3% of the 762.9 mm diameter of 255/45 R21 on paper, and within 20 mm of its width. That alone does not make them approved for your car: check the handbook or the door placard, and keep one size across an axle.
| Size | Overall diameter | Difference |
|---|---|---|
| 255/40 R22 | 762.8 mm | -0.0% |
| 255/50 R20 | 763 mm | +0.0% |
| 235/55 R20 | 766.5 mm | +0.5% |
| 235/50 R21 | 768.4 mm | +0.7% |
| 265/40 R22 | 770.8 mm | +1.0% |
| 275/40 R21 | 753.4 mm | -1.2% |
See all tyre sizes, or read how our tyre fitting works.
Frequently asked questions
Is 255/45 R21 the same as 255/45 ZR21?
Yes, the dimensions are the same. The Z marks a tyre rated for over 240 km/h (149 mph); the exact rating is the letter after the load index, such as W or Y. Fit at least the speed rating your handbook gives for the car.
Can I fit 255/40 R22 instead of 255/45 R21?
Only if 255/40 R22 is listed for your car. On paper it is 762.8 mm tall against 762.9 mm for 255/45 R21, a 0.0% difference, so the speedometer would barely change. It also needs a 22-inch wheel instead of a 21-inch one. Wheel width, arch clearance, load index and speed rating must suit the car too, so check the handbook or the door placard, and fit one size across an axle.
How tall is a 255/45 R21 tyre?
About 762.9 mm (30.0 inches) across when new and unloaded: the 21-inch rim (533.4 mm) plus two sidewalls of 114.8 mm, which is 45% of the 255 mm width. Real tyres differ by a few millimetres between brands and patterns.
Which cars use 255/45 R21 tyres?
Fitment listings give 255/45 R21 for the Porsche Macan Electric. One model can use several sizes depending on its wheels, so check the sidewall of your own tyres before you book.
Same-Day Tyre Fitting & Walk-Ins Welcome
New tyres fitted while you wait, plus puncture repairs, wheel balancing and battery replacement at our Park Royal workshop. No appointment needed for tyres, just call in.