Senior staff is L7.

Swe 2, Swe 3, senior, staff, senior staff, principal, distinguished, god

In that order, except god isn’t really a level it’s just Sanjay and Jeff.

Swe 2 is L3, goes up by one for each level, thus senior is 5, senior staff is 7, etc

At most garden variety BigCorps that I'm aware of, these days staff engineer is basically anyone with a decent amount of experience. A step above senior, that's about it. Principal is next, and actually does have a bit more meaning, but still not _that_ special. Based on everything I've read, Google L9 easily trumps both of those positions and by a fairly large margin.

The official titles are 5 is senior, 6 is staff, 7 is senior staff. That doesn't necessarily map to how titles are at other companies though, a 7 IC is already rare enough that many engineers won't interact with any for years; even most 6s are manager types.

Staff Engineer is L6, and Senior Staff is L7. These are quite high, the vast majority of engineers at Google won’t make it to these levels. Depending on the the team/org, they may tackle large, complex problems and dictate the direction of functional areas and organizational strategy.

Senior staff is L7. There are probably a hundred L7s for every L9, if not more.

I would estimate a senior staff engineer to be an L5 or L6 at Google