Tire Size Box

305/25R19 vs 295/30R19

295/30R19 compared with 305/25R19

+3.9% diameter, −0.4" width

295/30R19 is 25.97" tall vs 25.00". More than the 3% rule of thumb, so check carefully before switching.

25.0"19" rim3.0"12.0" wide
305/25R19 (solid) compared with 295/30R19 (dashed outline), drawn to scale

With 295/30R19 tires, when your speedometer says 60 mph you are really going

62.3 mph

295/30R19 is +0.96 inches (+3.9%) in overall diameter. That is more than the 3% most shops and makers recommend.

305/25R19295/30R19Difference%
Overall diameter25.00"25.97"+0.96"+3.9%
Section width12.01"11.61"−0.39"−3.3%
Sidewall height3.00"3.48"+0.48"+16.1%
Circumference78.55"81.58"+3.03"+3.9%
Revolutions per mile806.6776.6−30.0−3.7%

Speedometer difference

If your vehicle came with 305/25R19 and you fit 295/30R19, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.8 mph+0.8 mph
30 mph31.2 mph+1.2 mph
40 mph41.5 mph+1.5 mph
50 mph51.9 mph+1.9 mph
60 mph62.3 mph+2.3 mph
65 mph67.5 mph+2.5 mph
70 mph72.7 mph+2.7 mph
75 mph77.9 mph+2.9 mph
80 mph83.1 mph+3.1 mph

Each size on its own

Questions

Which is bigger, 305/25R19 or 295/30R19?
295/30R19 is taller by 0.96 inches (25.97" vs 25.00"). 305/25R19 is wider by 0.39 inches.
Can I replace 305/25R19 with 295/30R19?
It is not recommended without checking carefully. The diameter difference is +3.9%, more than the 3% most shops and makers allow. It will throw off the speedometer and may affect ABS, stability control and clearance.
How much will 295/30R19 change my speedometer?
When your speedometer reads 60 mph with 295/30R19 fitted (calibrated for 305/25R19), your real speed is 62.3 mph. Your odometer will under-count miles by about 3.9%.
Will 295/30R19 lift my vehicle?
Ride height changes by half the diameter difference: +0.48 inches of ground clearance at the axle.

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