I know that scales measure weight (a force) via displacement of a spring. I also know the difference between a force and a mass. I know that, on the moon, the numbers on a scale might be different (depending on the answer to this question). I've read through the few threads on this matter here, and there isn't a clear answer to my question: What are the numbers that a bathroom scale actually displays? Are the numbers displayed a force, or does the scale implicitly assume it is on Earth, account for this—and thus display a mass?