Sucralose is a sucrose molecule in which three of the -OH groups have been replaced by chlorine atoms.
Sucralose tastes sweet, with a slight off-taste that is described as "drying" or bitter by some tasters. It has a slightly slower onset of sweetness than sucrose, and the sweetness lingers a little longer than sucrose.
Sucralose provides no calories.
Sucralose is relatively stable. It can be used in baking applications.
Sucralose has been approved by the FDA, EFSA, and JECFA.
Sucralose has such high sweetness potency that it a sweetener packet only contains 11 to 12 milligrams. 99% of the material in the packet is maltodextrin, a simple starch.