- UNECE Regulation No. 30 — passenger-tire definitions, speed categories and load-capacity reference table.
- Transport Canada: Riding on Air — Canadian tire markings and safety context.
- Transport Canada tire safety standards — Canadian regulatory resources.
- NHTSA vPIC — official make/model identity data. It is not treated as an OEM tire-fitment or PSI source.
What we publish
Reference pages are published only when their required facts can be checked and they provide useful information. Calculated dimensions are clearly separated from manufacturer specifications and vehicle-fitment advice.