What Size Tire Is 285 70R17? | 33-Inch Specs, Plain English

This tire size is about 32.7 inches tall, 11.2 inches wide, with a sidewall just under 7.9 inches on a 17-inch wheel.

A 285 70R17 tire sits in that sweet spot many truck and SUV owners want: tall enough to earn the “33-inch” label, wide enough to add a planted stance, and still common enough that you can find solid all-terrain and highway options without a scavenger hunt.

That said, the code on the sidewall can look like alphabet soup if you haven’t broken one down before. Once you split it into width, sidewall height, construction, and wheel size, the numbers start to make sense.

What Size Tire Is 285 70R17? Real-World Measurements

Here’s what each part means:

• 285 is the nominal section width in millimeters.
• 70 means the sidewall height is 70% of that width.
• R means radial construction.
• 17 is the wheel diameter in inches.

Run the math and you get a tire that is about 11.2 inches wide. Each sidewall is about 199.5 mm, which comes out to 7.85 inches. Put two sidewalls around a 17-inch wheel and the overall diameter lands at about 32.71 inches, or 830.8 mm. Circumference comes out to about 102.8 inches, which works out to roughly 617 revolutions per mile.

That’s why people round this size up and call it a 33-inch tire. It’s close enough for shop talk and trail chatter. Still, “close enough” is not the same as exact. Tread design, wheel width, inflation pressure, and load spec can all nudge the mounted size a bit once the tire is on the vehicle.

Why People Call It A 33-Inch Tire

Most drivers do not speak in millimeters when they talk tires. They use the quick shorthand: 31s, 33s, 35s. A 285 70R17 lands just under 33 inches tall, but the true diameter is a touch smaller.

That shorthand is handy when you’re talking lift height, stance, or rough clearance needs. It gets less precise when you start comparing one size against another. A tire that is 32.2 inches tall and one that is 32.7 inches tall may both get called “33s,” yet that half-inch gap can still matter if your wheel wells are tight.

If the sidewall code still feels murky, Michelin’s tire-marking guide spells out how width, aspect ratio, construction, and wheel diameter are written on the tire itself.

Where This Size Changes Your Vehicle

Clearance And Rub Risk

A tire that stands 32.7 inches tall adds more than visual bulk. It changes how much room you have at the front bumper, fender liner, mud flap, upper control arm, and body mount. Diameter affects top-to-bottom clearance. Width affects side-to-side clearance. Both matter when the wheel is turned hard or the suspension compresses.

If you are stepping up from a smaller stock size, half of the diameter increase shows up as added radius. That sounds small on paper, yet it can be the difference between a clean turn and a faint scrub at full lock.

Gearing And Speedometer Reading

A taller tire travels farther with each full turn, so a jump in tire height can make the speedometer read a little low and soften acceleration a bit. Engine rpm at a given road speed may drop too. Some drivers like that calmer cruise feel. Others notice the change right away if the vehicle was geared tightly from the factory.

Width also shapes feel. A 285 is about 11.2 inches wide on paper, which is stout for many midsize trucks and a natural fit for many full-size rigs. On a narrow wheel, the sidewall may bulge more. On a wider wheel, the tread can sit flatter and fill out the wheel well differently.

Measurement	285 70R17 Value	What It Tells You
Section width	285 mm	Nominal width from sidewall to sidewall
Section width	11.2 in	Useful for wheel-well and suspension clearance checks
Aspect ratio	70%	Sidewall height is 70% of the tire width
One sidewall height	199.5 mm	The height of one sidewall before the tire is mounted
One sidewall height	7.85 in	Handy when comparing ride cushion and flex
Wheel diameter	17 in	The tire fits a 17-inch wheel
Overall diameter	32.71 in	The reason it gets called a 33-inch tire
Circumference	102.8 in	Shows how far the tire rolls in one turn
Revolutions per mile	About 617	Useful when comparing gearing and speedometer change

Will 285 70R17 Fit Your Truck Or SUV?

Sometimes yes, straight away. Sometimes no, not without trimming, a leveling kit, different wheels, or a bit of luck. Fitment depends on more than the tire size written on the sidewall.

These checks give you a much cleaner answer before you order:

• Look at the stock tire size on the door-jamb placard or in the owner’s manual.
• Check your wheel width and offset, not just wheel diameter.
• Turn the steering from lock to lock and inspect the tight spots.
• Think about suspension compression, not only parked clearance.
• Check spare-tire space if your spare lives under the vehicle.

There is another layer too: load index, speed rating, and treadwear marks. A tire can share the same 285 70R17 size and still behave quite differently. NHTSA’s tire safety page lays out how sidewall ratings and government tire grades work, which is handy when you are comparing one option against another.

Load Range Can Change The Feel

Two tires can both be 285 70R17 and still feel nothing alike on the road. A lighter P-metric tire may ride softer and weigh less. An LT tire in a heavier load range may ride firmer, carry more weight, and ask for different air pressures. That difference matters just as much as the raw size if your truck pulls a trailer, carries gear, or spends time on rocky trails.

The safest move is to match the job you do with the vehicle, then verify that the tire meets the placard or owner’s manual requirements for load and speed. Size gets all the attention, but the service description is part of the fit too.

Tire size	Overall diameter	How It Compares
275/70R17	32.16 in	About 0.55 in shorter and a bit narrower
285/70R17	32.71 in	The baseline “33-inch” size in this group
295/70R17	33.26 in	About 0.55 in taller and wider
285/75R17	33.83 in	About 1.12 in taller with the same nominal width

When This Size Makes Sense

A 285 70R17 works well for drivers who want a fuller stance and a little more ground clearance without jumping into a much taller tire. It is a common pick on off-road trims, leveled trucks, and SUVs that split time between pavement and dirt.

• It adds sidewall height for a cushier look and more give off pavement.
• It gives many trucks a stronger, more filled-out stance than narrower stock sizes.
• It stays easier to live with than taller jumps that push clearance, gearing, and spare-tire storage harder.

It can be a tougher fit on fully stock vehicles with tight front wheel wells or wheels that sit too far inward or outward. In those cases, a slightly narrower or shorter size may save a lot of trimming and guesswork.

Buying Tips Before You Order

Before you hit the buy button, check the brand’s spec sheet for the exact tire you want. Nominal size gets you close. Actual mounted width, tread width, and measured diameter get you closer. One 285 70R17 all-terrain can run chunkier than another when the sidewall stamp matches.

1. Confirm wheel width and offset.
2. Match load index and speed rating to the vehicle placard.
3. Measure clearance at full steering lock.
4. Think about spare-tire fit and any speedometer correction you may want.

If you just wanted the raw answer, here it is in plain English: a 285 70R17 tire is about 32.7 inches tall, 11.2 inches wide, and close enough to be called a 33-inch tire. If you wanted the practical answer too, it is this: treat it as a mild-to-medium size jump that can look great and work well, but only after you check clearance, wheel specs, and load rating.