Batting Average is the most popular statistic in baseball and it gives you the best idea of how you are performing as a hitter.
Batting Average = Hits / At Bats
Looking for a good batting average calculator?
Free Web-Based Batting Average Calculators:
TomorrowsPro.com - This site will calculate Batting Average, On-Base Percentage, On-Base + Slugging Percentage, and Slugging Percentage as well. It will track your entire baseball season and keep a running tally of all your stats as you complete each game.
All the other free sites make you save all of your game's stats in a spreadsheet and then give them the total Hits and At Bats so they can figure out the average.