What is the diameter difference between 265/35R19 and 275/30R19?

265/35R19 has an overall diameter of 26.3 inches (668 mm). 275/30R19 is 25.5 inches (648 mm). That's a 0.81 inch (21 mm) difference — 275/30R19 is shorter.

Will 275/30R19 cause speedometer error on a car fitted with 265/35R19?

Swapping 265/35R19 for 275/30R19 produces a speedometer error of about 3.1%. Your speedometer will read higher than your actual speed — a 60 mph indicated reading is really 58.2 mph. Anything under 3% is usually acceptable without recalibration.

How many revolutions per mile does each size do?

265/35R19 turns 767 revs per mile. 275/30R19 turns 791 revs per mile. Taller tyres turn fewer times per mile, which lowers effective final-drive ratio.

What's the sidewall height difference?

265/35R19 has a sidewall of 93 mm (3.65 in). 275/30R19 sidewall is 83 mm (3.25 in). Lower-profile sidewalls give sharper steering response but less bump compliance.

Is 275/30R19 a safe plus-size upgrade from 265/35R19?

A plus-size upgrade is considered safe when overall diameter stays within ±3% — here the difference is 3.1%. This swap is outside the typical ±3% safe range and may require speedometer recalibration or affect ABS / traction control behaviour.

Tire size comparison

265/35R19 vs 275/30R19

Overall diameter, sidewall, revs per mile, and speedometer error — 265/35R19 is the taller tire, with a 3.1% speedo delta when swapping.

265/35R19

26.3in

668 mm overall diameter

275/30R19

25.5in

648 mm overall diameter

Diameter Δ

0.81 in

Speedo error

3.1%

265/35R19 revs/mi

767

275/30R19 revs/mi

791

Outside the typical ±3% safe plus-size band — you may want speedometer recalibration, and this change can affect ABS or traction control behaviour.

Full spec

Side by side

Metric	265/35R19	275/30R19
Section width	265 mm	275 mm
Aspect ratio	35	30
Wheel diameter	19″	19″
Sidewall height	93 mm	83 mm
Overall diameter	26.3 in (668 mm)	25.5 in (648 mm)
Circumference	82.63 in	80.1 in
Revolutions / mile	767	791

Other comparisons for these sizes

245/45R17 vs 265/35R19 255/40R18 vs 265/35R19 265/35R18 vs 275/30R19 275/35R18 vs 275/30R19 245/35R19 vs 265/35R19 255/35R19 vs 265/35R19 255/40R19 vs 265/35R19 265/30R19 vs 275/30R19 265/30R19 vs 265/35R19 265/35R19 vs 275/30R20

FAQ

Frequently asked

What is the diameter difference between 265/35R19 and 275/30R19?: 265/35R19 has an overall diameter of 26.3 inches (668 mm). 275/30R19 is 25.5 inches (648 mm). That's a 0.81 inch (21 mm) difference — 275/30R19 is shorter.
Will 275/30R19 cause speedometer error on a car fitted with 265/35R19?: Swapping 265/35R19 for 275/30R19 produces a speedometer error of about 3.1%. Your speedometer will read higher than your actual speed — a 60 mph indicated reading is really 58.2 mph. Anything under 3% is usually acceptable without recalibration.
How many revolutions per mile does each size do?: 265/35R19 turns 767 revs per mile. 275/30R19 turns 791 revs per mile. Taller tyres turn fewer times per mile, which lowers effective final-drive ratio.
What's the sidewall height difference?: 265/35R19 has a sidewall of 93 mm (3.65 in). 275/30R19 sidewall is 83 mm (3.25 in). Lower-profile sidewalls give sharper steering response but less bump compliance.
Is 275/30R19 a safe plus-size upgrade from 265/35R19?: A plus-size upgrade is considered safe when overall diameter stays within ±3% — here the difference is 3.1%. This swap is outside the typical ±3% safe range and may require speedometer recalibration or affect ABS / traction control behaviour.