What matches are taken into account to compute those stats?

All normal and ranked games from the last 30 days are taken into account to compute the stats.

Will I get banned for using the Valofessor app?

Absolutely not! We ensure our apps are 100% Riot compliant and have a good working relationship with Riot to ensure it remains that way.

Where do you grab your data?

Riot APIs !

What is this rank displayed alongside my current ranking (gold for instance)?

This rankings aggregates Riot ranking in all regions to get your rank. (If you are Gold IV, you'll have a better rank than a Gold V player for instance). This rank is updated almost in real time.

What kind of partnership do you have with leagueofgraphs.com and porofessor.gg?

I'm the creator of League of Graphs and Porofessor :)

I have a question, how can I contact you?

Have a look at the contact page !