Plus sizing tires: can I put bigger tires on my car?
Short answer: usually yes, if you do it the plus sizing way. You fit a bigger wheel with a lower profile tire so the overall tire diameter stays close to stock, ideally within about 3 percent. The new tire also needs a load capacity and speed rating at least as high as the original, an approved rim width, and enough clearance. Use the plus size finder below, then check the result in our tire size comparison calculator.
Last updated: October 23, 2026
Jump to: What plus sizing means · Plus one and plus two example · The six rules · Plus size finder · Extra Load pressure · Tradeoffs · AWD and staggered setups
What does plus sizing mean?
Plus sizing is moving to a larger diameter wheel while choosing a tire with a lower aspect ratio (a shorter sidewall), so the outside diameter of the tire barely changes. Plus one means a wheel one inch larger, plus two means two inches larger, and so on. Width often grows a little too. Continental Tire’s plus sizing bulletin (PSIB 06-03) describes it as installing lower aspect ratio tires on wider, larger diameter rims, and says the original rolling circumference should be maintained as closely as possible.
Simply fitting a taller tire on the same wheel is a different change. It raises overall diameter, which affects speedometer readings and clearance, and the same 3 percent guidance applies. If you are new to reading sizes like 225/65R17, start with how to choose the right tire size.
Plus one and plus two example
Diameters below are calculated from the size itself (wheel diameter plus two sidewalls). Actual tires vary slightly by model, so check the maker’s published overall diameter or revolutions per mile.
| Setup | Size | Sidewall height | Overall diameter | Change vs stock |
|---|---|---|---|---|
| Stock (plus zero) | 205/55R16 | 4.44 in | 24.88 in | None |
| Plus one | 215/45R17 | 3.81 in | 24.62 in | About 1.0% smaller |
| Plus one | 225/45R17 | 3.99 in | 24.97 in | About 0.4% larger |
| Plus two | 225/40R18 | 3.54 in | 25.09 in | About 0.8% larger |
The six rules tire makers give for plus sizing
Continental’s bulletin lists six checks for every plus sizing job. In plain words:
- Load capacity: equal to or greater than the original equipment tire. Never pick a tire that carries less. Our load index and speed rating guide explains the numbers.
- Inflation pressure: never below the vehicle maker’s placard pressure, and keep any front to rear pressure difference the maker specifies. See how to read your door placard.
- Speed rating: equal to or greater than the original tires. The bulletin notes winter tires with a lower speed rating are generally acceptable, but that limits the vehicle’s maximum speed.
- Rolling circumference: as close to stock as possible. Under most circumstances a change within plus or minus 3 percent does not require adjusting the speedometer, ABS or stability control. If in doubt, follow the vehicle manufacturer.
- Tire and rim combination: only industry approved tire size and rim width pairings (standards bodies such as TRA, ETRTO or JATMA). The tire maker’s data book lists the approved rim widths for each size.
- Body and chassis clearance: check clearance through full suspension travel and full steering lock, allowing for tire growth and flex under load and cornering.
Plus size finder
Enter your current size and the wheel diameter you want. The finder lists common width and aspect ratio pairs whose overall diameter lands within 3 percent of your current tire, closest first. It runs in your browser and stores nothing. It does not know your rim width, load index or clearance, so treat its list as a starting point for a conversation with a tire professional.
Calculated from nominal sizes only. Real tires differ slightly by brand and tread depth. Compare any two sizes side by side, with speedometer error, in the tire size calculator.
Switching to Extra Load tires: pressure changes
Low profile plus size tires are often Extra Load (XL). Continental’s bulletin gives this guide for replacing a Standard Load original tire with a plus sized Extra Load tire, so the new tire carries at least the original load:
| XL replacement load index vs stock | Pressure change vs placard |
|---|---|
| Same as stock | Add about 6 psi (0.4 bar) |
| Stock + 1 | Add about 4 psi (0.3 bar) |
| Stock + 2 | Add about 3 psi (0.2 bar) |
| Stock + 3 | Add about 2 psi (0.1 bar) |
| Stock + 4 or more | Same as placard |
Never go above the maximum pressure molded on the sidewall. If your new pressure differs from the placard, write it down for anyone else who drives or buys the car. Your installer should confirm the figure for your exact tire.
What you gain and give up
- Often gained: sharper steering feel and a look many drivers like. Wider tires can add grip in dry corners.
- Often given up: a firmer ride, more exposure to pothole and curb damage on the wheel and tire, and usually higher prices for larger, low profile sizes. Heavier wheels can also add unsprung weight.
- Winter: many drivers go the other way in winter, a smaller wheel with a taller, narrower winter tire, as long as it clears the brakes. See our winter tires guide.
These are general tradeoffs described by tire makers and installers, not results of our own testing.
AWD, 4WD and staggered setups
Continental recommends that all wheel drive and four wheel drive vehicles run the same size on all four tires unless the vehicle came from the factory with a staggered fitment, meaning different sizes front and rear. Staggered setups need the vehicle maker’s guidance. Mixing sizes or tread depths on AWD can strain the drivetrain; our mixing tires guide covers when to replace two or four.
Informational only, not professional or safety advice. Your vehicle manual, the tire maker and a licensed installer take priority over this page.
FAQ
What is plus sizing on tires?
Plus sizing means fitting a larger diameter wheel with a lower profile tire so the overall tire diameter stays about the same. Plus one is one inch more wheel, plus two is two inches. Continental's plus sizing bulletin says the original rolling circumference should be kept as closely as possible.
Can I put bigger tires on my car?
Often yes, within limits. Continental's bulletin says load capacity and speed rating must be equal to or greater than the original tires, only industry approved tire and rim width combinations should be used, and body and chassis clearance must be checked through full suspension travel and steering lock.
How much bigger can tires be without affecting the speedometer?
Continental says that under most circumstances a change in rolling circumference within plus or minus 3 percent does not require adjusting the speedometer, ABS or stability control. Outside that range, or if in doubt, ask the vehicle manufacturer.
Do plus size tires need more air pressure?
Sometimes. Never run below the placard pressure. If a Standard Load tire is replaced by an Extra Load tire, Continental's chart adds pressure depending on the load index: up to 6 psi more when the load index is the same as the original. Never exceed the maximum pressure on the sidewall.
Does plus sizing affect ride comfort?
Usually a lower profile tire has a shorter sidewall, so ride can feel firmer and the wheel is more exposed to pothole damage. Steering response often feels sharper. These are general tradeoffs, not test results.
Can I plus size only the front or rear tires?
Continental recommends that all wheel drive and four wheel drive vehicles keep the same tire size on all four corners unless the vehicle came from the factory with a staggered fitment, and staggered setups need the vehicle maker's guidance.
Sources
Outbound links to public references. We paraphrase; visit the source for full wording and updates.
- Continental Tire, PSIB 06-03 Tire Plus Sizing for Passenger and Light Truck Vehicles (PDF): six plus sizing checks (load capacity, inflation, speed rating, rolling circumference within about 3%, approved rim widths, clearance); Standard Load to Extra Load pressure chart; AWD and staggered guidance
- NHTSA, Tire Safety (TireWise): use the vehicle’s placard and owner’s manual for recommended tire size and pressure; check pressure monthly when cold