What fielding percentage measures
Fielding percentage is the oldest defensive statistic in baseball. It answers a simple question: of all the balls a fielder had a chance to handle, what fraction did they handle cleanly? A shortstop who turns 200 grounders into outs and boots 6 has a fielding percentage of .971. The number is easy to compute and easy to understand, which is why it has appeared on the back of baseball cards for over a century.
How it works
The formula is:
fielding % = (PO + A) / (PO + A + E)where PO is putouts, A is assists, and E is errors. The denominator, putouts plus assists plus errors, is called total chances. Every play a fielder is involved in falls into one of those three buckets. This tool runs that division and then compares your result against the recent MLB average for the position you pick, so a .975 at shortstop reads very differently from a .975 at first base.
Tips, context, and limits
The big caveat is range. Fielding percentage punishes errors but says nothing about balls a fielder never reached. A statue at shortstop who only fields the easy ones can post a gleaming percentage while costing the team runs the entire season. That is why front offices now lean on Defensive Runs Saved (DRS) and Outs Above Average (OAA), which credit fielders for the difficulty and quantity of plays made, not just the ones cleanly handled. Use fielding percentage as a quick sanity check, then look to range metrics for the full defensive picture. For amateur play, the league averages shown are a rough guide — error scoring is stricter in the majors, so youth fielders should not expect to match them.