Will bigger tires fit?
Type your tire size and the one you want. See how much taller and wider it is, whether it usually fits, and what your speedometer will really mean.
Your answer
285/70R17 is 1.1 in taller than 265/70R17.
- Height change
- +1.1 in
- +3.5% overall height
- Width change
- +0.8 in
- Tread width, side to side
- When your speedometer says 65
- 67.3 mph
- Your real speed on the new tires
Side by side, to scale
Size by size
Your real speed
What you are really doing when the speedometer shows each speed, after the change.
Sizes come from the tire code. Real tires vary by a few tenths of an inch between brands and sit slightly lower under load.
How it works
- We read the sizeA code like 265/70R17 means a tire 265 mm wide, with sidewalls 70% as tall as it is wide, on a 17-inch wheel. From that we work out its height in inches.
- We compare the heightsThe tire industry's guideline is to stay within 3% of your current height. Past that, many trucks need a leveling kit or lift.
- We fix the speedometer mathTaller tires go farther with each turn, so you drive faster than the speedometer shows. We show your real speed.
Learn more
Simple answers about tire sizes, fit and speedometers.
Common questions
How do I find my current tire size?
It is printed on the side of every tire, in a code like 265/70R17. It is also on the sticker inside the driver's door frame, which lists the size your vehicle came with. Use the door sticker if you are not sure the tires on it now are stock.
What is the 3% rule for tire sizes?
The tire industry's long-standing guideline is to keep a replacement tire within 3% of the original overall height. Inside that range, your speedometer, anti-lock brakes, stability control and gearing stay close to how the factory set them. The calculator above shows the % change for you.
Will bigger tires mess up my speedometer?
Yes, a little. Taller tires travel farther each turn, so you are going faster than the speedometer shows, and your odometer counts fewer miles than you drive. A tire shop or dealer can often recalibrate it. The calculator shows your real speed at common speeds.
Do I need a leveling kit or lift for bigger tires?
Up to about 3% taller usually bolts right on. Beyond that, many trucks and SUVs need a leveling kit (which raises the front) or a lift kit, and sometimes trimming. It depends on your exact vehicle, wheels and suspension, so check with a tire or off-road shop.
Can I put wider tires on my stock wheels?
Often, but every tire size has a range of wheel widths it is approved for, listed in the tire maker's specs. Too narrow a wheel pinches the tire, and too wide stretches it. Wider tires can also rub on suspension parts even when the height is fine.
Do bigger tires lower gas mileage?
Usually. Bigger tires weigh more and take more effort to turn, so most drivers see somewhat lower mileage. Your odometer also counts fewer miles than you really drive, which makes your mileage look worse than it is unless you correct for it.
Are these measurements exact?
They are the sizes the tire code describes. Real tires of the same size can differ by a few tenths of an inch between brands and models, and they sit a little lower under the weight of the vehicle. Check the tire maker's spec sheet for exact numbers.
Is my information saved?
No. Everything is worked out in your browser and is never sent to us or stored anywhere.