Beyonce and Pharrell are a bunch of overachievers … the items they donated for a charity auction fetched 19 TIMES MORE than anticipated.

TMZ broke the story … Bey and P. Willy donated items auctioned off at Heritage Auctions to help raise money for The Lung Transplant Project… a non-profit that raises money and awareness to reduce transplant waiting list times.

Beyonce’s “Formation” tour hat was supposed to bring between 1 and 2 G’s … but after Monday’s auction closed it brought in a whopping $27,500!!!

Pharrell donated two pairs of adidas Originals … the first pair featured the hit-making producers’ John Hancock and an inspiring message, while the second pair will be custom-made for the winning bidder.

The kicks — which were estimated to haul in about a G — sold for $11,375. Score!!!