How to counter Renekton
Let us take a look on how to beat Renekton. We will look at champions who are strong against Renekton and who are weak against Renekton. Use win rate, gold difference and creep score difference at minute 10 to find the best 
Top champion who counters Renekton. You can already win in champion select with the right counters for Renekton. If you want to know how to counter Renekton then you need to take into account the best picks vs Renekton and the worst picks vs Renekton. This Renekton counter data is based on matches played by Pros on patch 15.12 and previous ones. It is important to see whether Pros counter picked Renekton or whether they played as Renekton.
Champions used by Pros to counter pick Renekton
Looking at the matches from Pros (see table Pros counter picked Renekton) we can see that they picked 
Ambessa most often to counter pick Renekton. The matchup Ambessa vs Renekton occured 69 times. Renekton has 42 wins and 27 losses in this matchup. Learn how to counter pick Ambessa to get another perspective on the data.
Lane outcome for Renekton
When looking at Renekton counters you will notice that win rates alone are not conclusional. Therefore we provide an overview (see table Lane Outcome) where you can see the lane outcome of Pros who played Renekton. The lane outcome of Renekton consists of three outcomes: Win, Loss or Draw. Let's take a look of Renekton lane and match outcome for specific matchups. Considering the lane outcome and the match outcome of a specific matchup, might enable you to find the right counter for Renekton.
Conclusion
Analyze the available data and learn how to beat Renekton. To master Renekton take also a look on Renekton builds and runes for Renekton. Good luck, Summoner!