225/65R19 vs 235/65R18 tire size comparison

Change either size and everything below updates.

Start from your car make, model, year
Current tire size
/R
xR
New tire size
/R
xR

Width in mm · aspect = sidewall height as a % of width · rim in inches

Flotation (LT) sizes, all in inches: overall diameter × section width, then rim

225/65R19: 30.52″ (775 mm) tall, 8.86″ (225 mm) wide, sidewall 5.76″ (146 mm) — 661 revolutions per mile.

Within the usual 3% rule

−1.60% diameter

Most fitment guides accept up to 3%. Check clearance at full lock and full suspension compression before committing.

  • Needs 18″ wheels: this tire does not fit your 19″ rims.
  • 10 mm wider: check inner clearance and that your rims are wide enough.

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Measurement225/65R19235/65R18Diff%
Overall diameter30.52″775 mm30.03″763 mm−0.49″−1.6%
Section width225.0 mm235.0 mm+10.0 mm+4.4%
Sidewall height146.3 mm152.8 mm+6.5 mm+4.4%
Rim diameter19″18″−1″−5.3%
Circumference95.87″2435 mm94.33″2396 mm−1.53″−1.6%
Revolutions per mileturns per distance; drives the odometer661411 /km672417 /km+11+1.6%
Ride height change——−0.24″ −6.2 mm

Speedometer reading

Speedo shows
60mph
97 km/h
Actual speed
59.0mph
95 km/h

Overlay

225/65R19235/65R18

Plus sizing: 225/65R19 on smaller or bigger wheels

Sizes fitted to cars that keep the overall diameter within 3% of 225/65R19 on a rim one inch smaller or up to two inches bigger, closest first.

RimSizeDiameterChangeCompare
R18 (−1) 245/65R18 30.54″ +0.1% Compare
235/65R18 30.03″ −1.6% Compare
R20 (+1) 245/55R20 30.61″ +0.3% Compare
235/55R20 30.18″ −1.1% Compare
R21 (+2) 235/50R21 30.25″ −0.9% Compare
255/45R21 30.04″ −1.6% Compare

How to use the tire size calculator

Put your current tire size — width, aspect ratio and rim diameter — into the first form, then your desired size into the second. You’ll get the difference between the new and the old size, plus the speedometer reading difference and your actual speed on the new set. Both metric and flotation (LT inch) sizes are supported.

The calculator helps you decide whether a set of tires and wheels will fit your car. To compare tires by brand and model instead, use our tire comparison tool; to look up factory sizes, browse by car make.

Changing wheels too? The wheel offset calculator shows how far a new wheel width and offset move the tire toward the suspension and the fender.

Reading a tire size

225/45R17
225
Section width in millimetres
45
Aspect ratio — sidewall height as a % of width
R
Radial construction
17
Rim diameter in inches

Full guide to the tire sidewall →