How do you weigh selfishness?

Put me on a scale.   

Self-centered means the majority of time, you think and focus on your own self-interests.

Selfishness on the other hand, is a focus so strong on one's own self interests that it takes precedence over the well-being and interests of others.

An example of being self-centered would be spending the majority of your time working for your own benefit and no one elses. It's not necessarily harmful, but it focuses on serving your own interests and no one else's.

An example of selfishness on the other hand, would be having a large surplus of money and food as a result of working for your own benefit, and not being willing to share any of it, even with those who are in desperate need.

How one's acts effects others.  I have no depends so if I spend discretionary money frivolously it is not shellfish.  But if one is a parent and his kid cannot say, go to a movie and pizza because the parent has spent the money on himself in a needless way, that is selfish.  

A tough but excellent question! 

Humans are all selfish to some extent. We all know people who always want to have things their way, never seem to consider the wants/needs/desires of others. People who only call when they want or need something. People who when you call them, immediately start talking about THEIR problems and don't bother to ask what's going on with you until they have to end the conversation. 

I think self-awareness is key to keeping selfishness in check. 

I would like to keep the answer to myself.

when people do what they want without caring how others feel about it