Tire Height & Diameter Calculator

Stock tire

 

New tire

 

Diameter change
+2.22 in
+7.0% vs stock
Speedometer reads
7.0% slow
at indicated 60: actual 64.2 mph
Revs per mile
−42 RPM
new total: 596

New tire is 2.22 in taller (+7.0% diameter). Speedometer reads 7.0% slow — at indicated 60 mph you're actually doing 64.2 mph.

3–7% — verify clearance
Side-by-side scale (true ratio) Stock New
31.61" 33.83" +2.22"

Reference values only. Manufacturer specifications override. Verify load index, speed rating, and physical clearance before driving — especially with upsizes greater than 3% diameter. Speedometer correction may require an OBD2 tuner. Tire-coverage rules vary by state.

Tire height & diameter calculator by RevRated  ·  Reviewed by Mike Reeves, ASE Master Technician