Car care · Elgin Auto Sales & Service Center · Elgin, IL
How to Read Tire Size on the Sidewall
The string of letters and numbers on a tire, such as P215/65R15 95H, tells you the tire type, width, sidewall height, construction, wheel size, load capacity and speed rating. Here is what each part means, how to read the DOT date code, and where to find the right size for your vehicle.
215section width in millimeters (example)
65aspect ratio: sidewall height as a % of width
15rim diameter in inches
95Hload index and speed symbol
The short answer
In the size P215/65R15 95H, P means a passenger car tire built to US standards, 215 is the section width in millimeters, 65 is the aspect ratio (sidewall height as a percentage of width), R means radial construction, 15 is the rim diameter in inches, 95 is the load index and H is the speed symbol. The right size for your vehicle is on the Tire and Loading Information label on the driver's door edge or door post and in your owner's manual.
How to read a tire size, step by step
The owner's manual example is P215/65R15 95H. Read it from left to right:
- P: the tire type. P means a passenger car tire based on US design standards. A size with no letter in front, such as 215/65R15 96H, is a passenger car tire based on European design standards.
- 215: the section width, in millimeters. NHTSA describes it as the width of the tire from sidewall edge to sidewall edge.
- 65: the aspect ratio, the ratio of section height to section width, in percent. A 65 means the sidewall is 65 percent as tall as the tire is wide. NHTSA notes that numbers of 70 or lower indicate a short sidewall for improved steering response.
- R: the construction code. R means radial construction; D means diagonal or bias construction.
- 15: the rim (wheel) diameter in inches. If you change wheel size, NHTSA says you will need tires that match the new wheel diameter.
- 95: the load index, a numerical code associated with the maximum load a tire can carry.
- H: the speed symbol, which indicates the range of speeds at which the tire can carry a load corresponding to its load index under certain operating conditions.
From the 2026 Jeep Cherokee Owner's Manual (Tire Safety Information: Tire Markings and Tire Sizing Chart) and NHTSA's Basic Tire Maintenance brochure, read November 3, 2026. These are the standard sidewall markings; the manual is used here because it lays them out in one chart.
Tire size chart: what each part means
The chart below covers the manual's size examples: P215/65R15XL 95H, 215/65R15 96H, LT235/85R16C, T145/80D18 103M and 31x10.5 R15 LT.
| Part | Example | What it means |
|---|---|---|
| Tire type | P, blank, LT, T or S | P = passenger tire (US standards); blank = passenger tire (European standards); LT = light truck tire (US standards); T or S = temporary spare |
| Overall diameter | 31 | Overall diameter in inches, used on high flotation sizes |
| Section width | 215, 235, 145 (or 10.5) | Width in millimeters (or in inches on high flotation sizes) |
| Aspect ratio | 65, 85, 80 | Section height as a percentage of section width |
| Construction | R or D | R = radial; D = diagonal or bias |
| Rim diameter | 15, 16, 18 | Wheel diameter in inches |
| Load index | 95 | Numerical code for the maximum load the tire can carry |
| Speed symbol | H | Range of speeds at which the tire can carry its rated load under specified conditions |
| Load identification | XL, LL, C to G | XL = extra load (reinforced); LL = light load; C, D, E, F, G = load range. No symbol means a Standard Load (SL) tire. |
From the 2026 Jeep Cherokee Owner's Manual, Tire Sizing Chart, read November 3, 2026.
P-metric, LT, spare and high flotation sizes
P-metric (passenger)
The letter P is molded into the sidewall before the size. Example: P215/65R15 95H.
Euro-metric (passenger)
The size begins with the section width and has no P. Example: 215/65R15 96H.
LT-metric (light truck)
The same layout as P-metric, but with LT molded before the size. Example: LT235/85R16.
Temporary spare
Temporary high pressure compact spares have T or S before the size. Example: T145/80D18 103M. They are for temporary emergency use only.
High flotation
Based on US design standards and starting with the overall tire diameter. Example: 31x10.5 R15 LT.
From the 2026 Jeep Cherokee Owner's Manual (Tire Markings) and NHTSA's Basic Tire Maintenance brochure, read November 3, 2026.
Load index and speed symbol
The two characters after the size, such as 95H, are the service description. The load index (95) is a code for how much weight each tire can support, and the speed symbol (H) indicates the speed range at which the tire can carry that load. The manual adds that the maximum speed for a speed symbol should only be reached under specified operating conditions such as tire pressure, vehicle loading, road conditions and posted speed limits.
NHTSA notes that the load index may not appear on every tire because it is not required by law, and that tires with a maximum speed capability over 149 mph sometimes use the letters ZR in the size.
When you replace tires, the manual says never to use a tire with a smaller load index or capacity than the original, and to use tires with adequate speed capability. The load index and speed symbol for your vehicle are on the original equipment tire sidewall.
From the 2026 Jeep Cherokee Owner's Manual (Tire Sizing Chart; Replacement Tires) and NHTSA's Basic Tire Maintenance brochure, read November 3, 2026.
How to read the DOT code and tire date
The Tire Identification Number (TIN) starts with DOT, which certifies that the tire complies with US Department of Transportation tire safety standards. In the manual's example, DOT MA L9 ABCD 0301:
- MA: a two-digit code for the manufacturing location.
- L9: a two-digit code for the tire size.
- ABCD: a one- to four-digit code used by the tire manufacturer.
- 0301: the week and year the tire was made. 03 is the third week and 01 is 2001.
The TIN may be on one or both sides of the tire, but the date code may be on only one side, so check both. Before July 2000, tire makers were only required to use one digit for the year. NHTSA says some vehicle and tire manufacturers recommend replacing tires that are six to 10 years old regardless of tread, and that you cannot detect tire aging just by looking. See our guides to when to replace tires and tire tread depth.
From the 2026 Jeep Cherokee Owner's Manual (Tire Identification Number) and NHTSA's Tire Safety Ratings and Awareness page, read November 3, 2026.
Other markings on the sidewall
Maximum load
The maximum load the tire is designed to carry, shown in kilograms and pounds.
Maximum pressure
The maximum permissible cold inflation pressure for the tire. It is not the pressure to run: NHTSA says the correct pressure is what the vehicle manufacturer lists, not what is on the tire.
Treadwear grade
A comparative wear rating. The higher the number, the longer the tread should take to wear down.
Traction grade
The tire's ability to stop on wet pavement, graded AA, A, B and C from highest to lowest.
Temperature grade
Resistance to heat, graded A, B and C, for a tire that is properly inflated and not overloaded.
From the 2026 Jeep Cherokee Owner's Manual (Tire Markings; Tire Terminology) and NHTSA's tire page and Basic Tire Maintenance brochure, read November 3, 2026.
Where to find the right tire size for your car
The size on the tires now on your car may not be the size the car came with. NHTSA says to check your owner's manual or the Tire and Loading Information label on the driver's side door edge or post for the correct size, and to buy new tires that are the same size as the vehicle's original tires. NHTSA's brochure says these labels can also be on the glove-box door or inside the trunk lid.
The manual recommends tires equivalent to the originals in size, quality and performance, replacing front or rear tires as a pair, and warns that tires of a different size may cause false speedometer and odometer readings. Checking pressure? Use the number on the same label; our tire pressure light guide explains why.
From NHTSA's Tire Safety Ratings and Awareness page and Basic Tire Maintenance brochure, and the 2026 Jeep Cherokee Owner's Manual (Replacement Tires), read November 3, 2026.
Tire help at Elgin Auto Sales & Service Center
Our service department works on new and pre-owned vehicles, including Toyota, GMC, Buick, Honda, Kia and Hyundai models, and offers tire rotation and balancing. Not sure your tires are the right size or how old they are? Ask us to look at them at your next visit. Our tire rotation guide covers how often to rotate.
Our service department at 1200 E. Chicago St. in Elgin is open Monday to Friday 8 a.m. to 5 p.m. and Saturday 8 a.m. to 4 p.m., and is closed Sunday. Schedule service, see our service specials or get directions.
Tire size FAQ
What does P215/65R15 95H mean?
P is a passenger tire built to US standards, 215 is the width in millimeters, 65 is the aspect ratio (sidewall height as a percent of width), R is radial construction, 15 is the rim diameter in inches, 95 is the load index and H is the speed symbol.
What is the aspect ratio on a tire?
It is the ratio of the sidewall (section) height to the section width, in percent. A 65 means the sidewall is 65 percent as tall as the tire is wide.
Where do I find my car's tire size?
On the Tire and Loading Information label on the driver's side door edge or door post and in the owner's manual. NHTSA recommends new tires the same size as the vehicle's original tires.
How do I tell how old my tires are?
Find the DOT Tire Identification Number on the sidewall. The last four digits are the week and year the tire was made, so 0301 means the third week of 2001. Check both sides of the tire, because the date code may be on only one.
What does LT mean on a tire?
LT means a light truck tire based on US design standards. The size reads like a P-metric size, with LT in front, for example LT235/85R16.
Should I inflate my tires to the pressure on the sidewall?
No. The sidewall shows the maximum pressure. NHTSA says the correct pressure is the one the vehicle manufacturer lists on the door label or in the owner's manual.
What are your service hours?
Monday to Friday 8 a.m. to 5 p.m. and Saturday 8 a.m. to 4 p.m. We are closed Sunday.
Questions about your tires?
Schedule service at 1200 E. Chicago St. in Elgin and ask us to check your tires.
Sources
The size chart, DOT code and replacement guidance are from the tire safety section of the 2026 Jeep Cherokee Owner's Manual, which explains the standard sidewall markings used on passenger and light truck tires; other details are from NHTSA. All read November 3, 2026. Your own vehicle's size and pressure are on its door label and in its manual. Service hours are from our website, checked the same day.
- 2026 Jeep Cherokee Owner's Manual (Tire Safety Information: Tire Markings, Tire Sizing Chart, Tire Identification Number; Replacement Tires), Jeep / Mopar, read November 3, 2026
- Tire Safety Ratings and Awareness (NHTSA), NHTSA, read November 3, 2026
- Safety First: Basic Tire Maintenance, DOT HS 809 361 (NHTSA), NHTSA, read November 3, 2026
- Service department, Elgin Auto Sales & Service Center
- Home page: address and service hours, Elgin Auto Sales & Service Center