Amazon's SDE levels determine your interview structure:
SDE I (L4): - years experience. coding rounds, no system design. Focus on data structures and algorithms. Total comp: \180$280$K.
SDE II (L5): - years. coding rounds + system design round. Most common hire level. Total comp: \250$400$K.
Senior SDE (L6): + years. Deeper system design scrutiny. Expected to show architectural thinking. Total comp: \350$550$K.
Principal (L7): Rare external hires. Architecture-level interviews. Total comp: \500+$.