Short Answer:
They are all calorie free or nearly calorie free when used in normal servings.
Saccharin (sweet n' Low) has approx 1 calorie per gram
Sucralose (Splenda) appears to be truly calorie free
Aspartame (Nutrasweet & Equal) has approx 1 calorie per gram
Long answer:
They are all so much sweeter (tasting) than sugar that any minimal calorie content they might have is overcome by the fact that so little is used (by weight).
Saccharin has approx 25% of the calories as carbohydrate (sugars and starches) by weight. It has .9 calories per gram vs. sugar which has 4 calories per gram.
This is offset by the fact that it is 10 times sweeter. So... If you substitute saccharin for sugar you will probably use 1/10th the sweetener by wt, or 1 gram vs. 10 grams.
So let's say 1 gram (1 sweet n' low packet) of saccharin is used instead of 10 grams (approx 2 1/2 teaspoons) of sugar. 10 grams of sugar would have had 40 calories. The 1 gram of saccharin has .9 calories per gram, or approx. 1 calorie (1 gram x .9 calories per gram = .9 calories).
So, instead of 40 calories, you got 1 calorie. Saccharin relies more on the fact that it is REALLY sweet than the fact that it has fewer calories by weight.
BTW, since a packet of any of the artificial sweeteners is considered to have fewer than 5 calories per serving, it can (must?) be labeled as zero calories.
Sucralose appears to be actually calorie free. 0.000... calories per gram. (and is approx 600 times sweeter than sugar!)
Though I never did hear back from "Ask the food scientist" at Equal.com, I did stumble across a few things that came from mainstream sources (e.g. FDA, manufacturers, etc.).
Equal states that aspartame is 200 times sweeter than sugar. It has about 1 calorie per gram. A teaspoon of sugar weighs about 4 grams, and has about 16 calories. The good folks at Equal.com suggest you replace 1 tsp of sugar with 0.5 grams (1/2 a packet) of Equal (aspartame). But, if it's 200 times sweeter (presumably by weight), then 1/2 a packet should be able to replace 25 tsp of sugar, not 1 tsp. Not sure where this disparity comes from.
At any rate, Aspartame appears to give you 97% fewer calories vs. sugar (1/2 a calorie instead of 16).
If you are searching for more info, don't confuse Equal with "Equal Sugar Lite", which seems to be a mix of real sugar and aspartame. It has significantly more calories than aspartame, but significantly fewer than sugar.
My "mainstream Sources":
http://www.calorie-counter.net/toppings-calories/nutrasweet.htm
http://www.equal.com/faq/faq.html#7
Usually 5
It's 500 calories since it's all about the flour and sugar and sweetener.
The artificial sweetener made from amino acids is aspartame. It is composed of two amino acids, phenylalanine and aspartic acid, and is commonly used as a sugar substitute in many foods and beverages.
Truvia is a natural zero-calorie sweetener. So... zero
Regular sweetner is 20 calories per packet. Artificial sweetner has no calories per packet.
trace amounts based on quantity - be more concerned about artificial colors
Each meal should have 600 calories or more
The ones that I buy in the supermarket have 180 calories each! The ones that I buy in the supermarket have 180 calories each!
there are about 100 calories in each ounce of absinthe.
About 30 calories each.
16 calories each
their are 1.5 calories in each gram of fat.