The size code is essential—but it is not the whole specification
A buyer may search for “315/80R22.5” or “11R24.5”, but the final order also needs brand, pattern, load and speed markings, construction, axle application and quantity. Products sharing a nominal size can have different approved rims, dimensions, tread depths and service roles.
Use this guide to read the basic format. Final fitment and load decisions must come from current vehicle, wheel and tyre-manufacturer information.
Reviewed 2026-08-26 · For wholesale planning; final specifications and import requirements must be confirmed for each order.
How to read a metric truck tyre size
In 315/80R22.5, “315” is the nominal section width in millimetres, “80” is the aspect ratio, “R” indicates radial construction and “22.5” is the nominal rim diameter in inches. The designation describes a size family; exact overall diameter and section width can vary by pattern, approved rim and manufacturer.
Other catalogue examples include 295/75R22.5, 295/80R22.5, 275/70R22.5 and 385/65R22.5. Do not compare only the first number. Aspect ratio and rim diameter change the package, and load/speed markings remain separate.
How to read an inch-based commercial size
In 11R22.5, “11” is the nominal section width in inches, “R” indicates radial construction and “22.5” is the rim diameter in inches. In 11R24.5, the rim diameter changes to 24.5 inches. A similar-looking tyre cannot be mounted on a different rim diameter.
Legacy or specialist designations may use formats such as 9.00R20 or 10.00R20. Confirm whether the product is tubeless or tube-type, the approved rim and complete load information. Never assume the dot or dash is only cosmetic.
The markings that complete the buying specification
Load index or range
Connects the tyre to load capacity under defined conditions; use current manufacturer tables.
Speed symbol
Indicates the referenced speed category under standardised conditions; it is not a recommended operating speed.
Ply rating
A strength/load-class reference, not a literal count of physical plies in a modern radial tyre.
Pattern and application
Distinguishes steer, drive, trailer, all-position, highway, regional and mixed-service products.
Single/dual data
Commercial tyres may have different load references for single and dual fitment.
From sidewall photo to approved order line
Capture the complete sidewall, not a cropped size. Record the brand, model or pattern, size, load and speed markings, load range or ply reference, DOT or production code where relevant and tube status. Add the vehicle, axle and duty cycle.
Send the information with required quantities. When the supplier proposes a product, compare its technical sheet with the need. If it is an alternative size or marking, obtain qualified approval before purchase.
For general tyre-safety background, see NHTSA TireWise. Destination regulations and fleet rules may differ.
Frequently asked questions
Are 11R22.5 and 295/75R22.5 the same?
They are often compared because their dimensions can be similar, but they are different designations. Confirm rim, dimensions, load, clearance and approved fitment.
Does 16PR mean the tyre contains sixteen physical plies?
Ply rating is a strength or load-class reference; it does not necessarily describe the literal number of body plies in a modern radial tyre.
Can I order using only a tyre size?
A size starts the search, but a safe commercial order also needs application, load and speed requirement, pattern or service type, quantity and destination.
Send a quote request that can be priced properly
Include your tyre sizes, quantities, preferred brands or quality tier, destination port and target timing. Thai Tire can then confirm current availability, a practical size mix and the next export step.
