How NPB Magic Numbers Are Calculated (With Ties in the Mix)

How NPB calculates winning percentage

Like the KBO, NPB allows games to end in a tie (引き分け). Winning percentage is wins ÷ (wins + losses) - ties count toward games played but appear in neither the numerator nor denominator. That means a team with several ties can have a higher winning percentage than a team with the same number of wins but fewer ties.

Magic numbers account for ties directly

This site's magic numbers work from the maximum number of decisive (win/loss) games each team can still play - the 143-game schedule minus games already decided as ties - then solve for the point where even a worst-case finish (the rival wins out, you lose out) can't catch up in winning percentage. That's more accurate than just tracking games back.

Reading the numbers

• A number - how many more wins (or rival losses) are needed to clinch that place or better.
• Clinched - the rival can't catch up in winning percentage even with a perfect finish.
• Impossible - even winning out, this team can't pass the rival's current percentage.
• Rival - the specific team whose remaining games matter most for that cutoff.

Teams can end up with slightly different game counts (rained-out ties usually aren't replayed). This site re-fetches npb.jp's official standings and recalculates from that point in time.