How accurate is the myFico scoring simulator

[Anonymous]

Specifically, I am curious to know how much of a score increase can be expected for paying all of my bills on time, no new negatives report, and utilization doesn't change.

So in a perfect world if everything stays the same but my AAoA increases by 1 month, is the simulator accurate in expecting a roughly 5 pt increase?

[Anonymous]

I can tell you I did a simulator test. I paid down my credit card debt significantly last month. My scores rose to within 3-4 points of what the simulator predicted.  Was happy to find out it's not a worthless tool!