How do American universities interpret Canadian grades?

I am a rising junior in Canada looking at applying to American universities.

In grade 9 I received a mid 80s GPA (an 85+ is a 4.0) and my GPA on the 4.0 scale was about 3.9. However, I know that many American institutions consider 80s to be a 3.0 or 2.7. I am unsure about which calculation American universities will use.

In grade 10 I achieved high 90s in almost every class and had a 4.0 by either definition.

Will American schools consider my grade 9 GPA to be a 3.9 or closer to a 3.0?

American universities are well aware that Canadian high schools do not have the level of grace inflation that exists in many US schools and they will evaluate your application in that context.

Other than that, there is no blanket statement to be made on how every college will interpret grades.