How to counter Jarvan IV
Let us take a look on how to beat Jarvan IV. We will look at champions who are strong against Jarvan IV and who are weak against Jarvan IV. Use win rate, gold difference and creep score difference at minute 10 to find the best 
Jungle champion who counters Jarvan IV. You can already win in champion select with the right counters for Jarvan IV. If you want to know how to counter Jarvan IV then you need to take into account the best picks vs Jarvan IV and the worst picks vs Jarvan IV. This Jarvan IV counter data is based on matches played by Pros on patch 15.11 and previous ones. It is important to see whether Pros counter picked Jarvan IV or whether they played as Jarvan IV.
Champions used by Pros to counter pick Jarvan IV
Looking at the matches from Pros (see table Pros counter picked Jarvan IV) we can see that they picked 
Xin Zhao most often to counter pick Jarvan IV. The matchup Xin Zhao vs Jarvan IV occured 28 times. Jarvan IV has 18 wins and 10 losses in this matchup. Learn how to counter pick Xin Zhao to get another perspective on the data.
Lane outcome for Jarvan IV
When looking at Jarvan IV 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 Jarvan IV. The lane outcome of Jarvan IV consists of three outcomes: Win, Loss or Draw. Let's take a look of Jarvan IV 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 Jarvan IV.
Conclusion
Analyze the available data and learn how to beat Jarvan IV. To master Jarvan IV take also a look on Jarvan IV builds and runes for Jarvan IV. Good luck, Summoner!