Why 45% can beat 50%: effective field goal percentage explained

The quick read

• eFG% adjusts shooting percentage for the extra point from a made three-pointer.
• It does not measure an entire offense or include free throws and turnovers.

Shot value changes the comparison

Two teams can make different shares of their shots and still produce the same points from the field. The missing information is the value of the shots they made. Effective field goal percentage, usually written eFG%, helps reveal that difference.

The eFG% calculation

The NBA glossary gives the calculation: eFG% = (FGM + 0.5 × 3PM) ÷ FGA. NBA statistical glossary. It can feel puzzling to watch your team make a higher share of its shots and still trail; separating twos and threes is often the first satisfying clue.

Hold the attempt count constant

Consider two imaginary teams, each taking twenty field-goal attempts. We are deliberately leaving out free throws and every other possession event so the shooting arithmetic is visible.

Fewer makes can produce more points

Team A makes 50% of its attempts. Team B makes 45%. Yet B scores two more points from the same number of attempts. The made three-pointers explain the difference.

Compare the adjusted percentages

For A, the eFG% calculation is (10 + 0.5 × 0) ÷ 20 = 50%. For B, it is (9 + 0.5 × 4) ÷ 20 = 55%. The adjustment makes the comparison more useful when the mix of made twos and threes differs.

The extra half reflects the extra point

The formula adds half of each made three to the numerator because an ordinary field goal is worth two points and a three is worth one additional point. Expressing that extra value on a two-point scale requires half a make.

Check the result on a two-point scale

You can check the arithmetic another way. B’s twenty-two field-goal points are equivalent to eleven made two-pointers. Eleven divided by twenty attempts is 55%. No shot has been physically split; the formula simply compares scoring output on a common scale.

Other possession events still matter

Our example fixed the number of field-goal attempts. Real games do not. A team can shoot efficiently while losing possessions through turnovers or allowing repeated offensive rebounds. It may also concede free throws or fail to generate them itself.

Free throws can reverse the scoring lead

Imagine B keeps its twenty-two field-goal points but adds no free throws. A adds five free-throw points to its twenty from the field. A now has twenty-five points to B’s twenty-two. The original eFG% values remain unchanged because the measure was designed around field-goal attempts.

Match the statistic to its question

That is a limitation of the question being asked, not an arithmetic error. A shooting measure helps explain shooting. A full offensive assessment needs more information about how possessions began, ended and continued.

Ask how the attempts were created

When you see a high eFG%, ask how the team created its attempts. Were shooters open because a defender had to help at the rim? Were difficult attempts falling at an unusual rate? Did the same approach produce useful shots when the opponent changed coverage?

Connect shooting output to off-ball movement

For a practical example of that first question, read our guide to Stephen Curry’s movement without the ball. A final shooting percentage records the result of an attempt; the passes, screens and defensive decisions before it help explain why that attempt became available.