Nominal capacity
Nominal capacity is the intended or commonly referenced filling size. It normally allows headspace for filling control, closure engagement and product expansion.
Brimful capacity
Brimful capacity is the volume to the very top of the container. It is a dimensional reference, not a recommended commercial fill level.
Use the source data carefully
A practical fill level depends on product properties, filling temperature, closure and transport requirements. Do not infer one from the other when source data is uncertain.