Fact is that artificial sweeteners are sweeter than sugar is part of the reason why they can
claim to be lower in calories. The fact that the sweetener is several times
sweeter than sugar means you can use a lot less of it in your desserts or in
your coffee and still get a similar result.
The other
artificial sweeteners are not as sweet as Splenda, but are still much sweeter
than sugar. Equal is 160-200 times sweeter than sugar, and Sweet ‘n’ Low is
300-500 times sweeter.
Source
Source