Splenda! But, beware, they've also added fructose to the flavors I checked out. It's also fat free with added starch.

Note on guesstimating yogurt carbs. I take the sugar content and subtract 8g for the little bacteria who eat them. Then add that to the "other carbs."

I would guesstimate Mixed Berry flavor with 15g carbs, 13g sugars as 7g carbs, 5g coming from sugars.