How do you know whether you are a good person or not?

I like to think I am but nobody is good through and through. We all do bad things sometimes. How do we know whether we are overall more good than bad? Is it something you just know in your heart if you're true to yourself or can we never say for certain? How do I know if my heart will weigh too much on Maat's scale?

What's the forgivable leeway for being "merely human"? i am not talking in terms of "eternal punishment" or jack like that, just on the human integrity level how do we know we are good deep down inside or not?

:/