Sliding down the label to the total carbohydrates it reads sugars “4g,” or “4 grams.” This important bit of information is your key to converting grams into teaspoons. Four grams of sugar is equal to one teaspoon. To be precise, 4.2 grams equals a teaspoon, but the nutrition facts rounds this number up to four grams. Using this equation you can easily look at any food product to see how much sugar it contains.