305/30R22 vs 295/35R21 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

305/30R22: 29.20″ (742 mm) tall, 12.01″ (305 mm) wide, sidewall 3.60″ (92 mm) — 691 revolutions per mile.

Well within tolerance

−0.26% diameter

The overall diameter changes by less than 1.5%, so speedometer error is negligible and ride height barely moves.

  • Needs 21″ wheels: this tire does not fit your 22″ rims.
  • 10 mm narrower: check the tire is approved for your rim width.

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Measurement305/30R22295/35R21Diff%
Overall diameter29.20″742 mm29.13″740 mm−0.07″−0.3%
Section width305.0 mm295.0 mm−10.0 mm−3.3%
Sidewall height91.5 mm103.3 mm+11.8 mm+12.8%
Rim diameter22″21″−1″−4.5%
Circumference91.75″2330 mm91.51″2324 mm−0.24″−0.3%
Revolutions per mileturns per distance; drives the odometer691429 /km692430 /km+2+0.3%
Ride height change——−0.04″ −1.0 mm

Speedometer reading

Speedo shows
60mph
97 km/h
Actual speed
59.8mph
96 km/h

Overlay

305/30R22295/35R21

Plus sizing: 305/30R22 on smaller or bigger wheels

Sizes fitted to cars that keep the overall diameter within 3% of 305/30R22 on a rim one inch smaller or up to two inches bigger, closest first.

RimSizeDiameterChangeCompare
R21 (−1) 295/35R21 29.13″ −0.3% Compare
305/35R21 29.41″ +0.7% 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 →

Sizes often compared with 305/30R22