From a Wall Street Journal online article by Lettie Teague

There is no official definition of what constitutes a dry wine in the U.S. The amount of sugar left in the wine after fermentation or added afterward is, however, sometimes noted on a wine’s label, in grams per liter. According to Mr. Ramey, a wine generally considered dry would have less than 1 gram per liter RS (residual sugar), or 0.1%. Beyond that, a wine with 1% RS (10 grams per liter) is off-dry, and a wine at 3% RS (30 grams per liter) or above is sweet.

WHAT’S A DRY WINE? If this seems like a question with a straightforward answer, then you probably don’t work in a wine store or restaurant. Retailers and sommeliers tell me they are regularly asked to recommend dry wines by customers who don’t seem to know what they really want. These customers offer examples of the “dry” wines they favor—which often turn out to be technically sweet.

To read more click on the following link:  https://www.wsj.com/articles/are-you-sure-that-wine-you-ordered-is-actually-dry-11566492508