Steering feel
Balanced, OEM-style response
A familiar OEM feel — predictable inputs without trade-offs.
Tire size meaning
255/40 R17
What the numbers on a 255/40 R17 tire actually mean — width, sidewall, construction and rim — explained in plain language with real-world driving context.
Direct answer
What does 255/40 R17 mean?
255/40 R17 is a metric tire size: 255 mm wide, a sidewall 40% of that width (102 mm), radial construction, fitted to a 17-inch wheel. Overall diameter ≈ 636 mm.
- 255
- Section width in mm (sidewall to sidewall).
- 40
- Aspect ratio — sidewall is 40% of width (102 mm).
- R
- Radial construction — the modern layered build.
- 17
- Wheel rim diameter in inches (432 mm).
Ø 636 mm · 25.03″ · 501 revs/km
Dimensional breakdown
- Section width
- 255 mm
- Aspect ratio
- 40%
- Sidewall height
- 102.0 mm
- Rim diameter
- 17″ (431.8 mm)
- Overall diameter
- 636 mm
- Circumference
- 1.997 m
- Revs per km
- 501
- Construction
- Radial (R)
What 255/40 R17 feels like on the road
A 255/40 R17 tire is a low-profile sporty tire. With a sidewall of 102 mm, it gives precise turn-in with a reasonable ride compromise — typical for sport sedans and hot hatches.
The 255 mm contact width delivers maximum contact patch for high-performance and SUV applications. Combined with a 17-inch wheel, this size is most commonly found on mid-size sedans, sport trims and modern crossovers.
At highway speed each tire completes about 501 revolutions per kilometre — the figure your speedometer and ABS were calibrated against if 255/40 R17 is the OEM specification.
Common alternatives to 255/40 R17
Sizes within ±3% overall diameter — generally safe swaps for speedometer accuracy and clearance. Click any size to open a full side-by-side comparison.
Driver feel · telemetry
What 255/40 R17 usually feels like
A driver-perspective read on this size — steering, comfort, highway stability and rough-road behavior.
Ride comfort
Comfortable daily ride
A balanced compromise — bumps muted, steering still precise.
Highway stability
Planted at highway speed
Wider contact patch resists crosswinds and tramlining — strong straight-line confidence.
Pothole comfort
Reasonable impact protection
Enough sidewall to protect the rim from typical urban hits.
Sporty vs OEM tone
Balanced everyday character
A factory-style balance between feel, comfort and grip.
Sidewall102 mm
Ø636 mm
Width255 mm
Revs/km501
Related tire sizes for 255/40 R17
Explore neighbouring sizes by intent — similar, wider, lower-profile, OEM-safe, or aggressive. Each link opens a full side-by-side comparison.