Splenda is a natural sugar substitute made from sucralose and maltodextrin. While it is touted as being a "no calorie" sweetener, this is only true when you use small amounts. When substituting for sugar in baking or other recipes, you must consider the calorie content per cup.
According to the Low Carb Freedom website, Splenda contains 96 calories per cup. In comparison, sugar contains 774 calories per cup, reports Calorie King.
The Splenda company website states that you should use the same amount of Splenda as you would sugar when following a recipe. If you choose to use Splenda Sugar Blend or Splenda Brown Sugar Blend, however, you should use only half as much of the sweetener. If you purchase Splenda packets, use 24 packets to equal 1 cup of sweetener.
If you need to limit the number of carbohydrates that you consume, using Splenda in place of sugar may make sense. While sugar contains 200 g of carbohydrates per cup, Splenda contains only 24.