Metrics calculation

Hi guys.
I have been studying Sonarqube and so far i read the whitepaper that explains the funcionalities in a very detailed way. Unfortunately i didn’t find anything (neither in the official documentation ) to understand how the differents metrics are calculated before being visualized on the interface.
I mean that i would like to know if exits a whitepaper that contains a more technical documentation that explains how sonarqube compute the different results; for example, if sonarqube tells me that i need 10 days to fix a particular smell, how it obtains this value? which formula used? and is this formula a notorious formula or was implemented ad hoc?
Hope i explained clearly what i need and mostly that these informations are available to everyone.


The Technical Debt is the sum of the Technical Debt estimates for the underlying issues. Most issues have a fixed estimate, which is just that - an estimate on our parts. Some issues have estimates that are scaled to the scope of the issue. For example, a Cognitive Complexity score of 1 over the threshold will have a lower estimate than one with a score of 20 over the threshold. But again, these are estimates / best guesses on our part.