Soon, those jaw-dropping numbers will be impossible to avoid.
According to TheDailyBeast.com, three of the worst offenders are: Sonic's Supersonic Cheeseburger at 898 calories; Burger king's BK Quad Stacker with 930 calories; and most fattening is Wendy's Baconator Triple, which has 1,330 calories. The Wendy's burger has the entire daily allowance for a woman and more than half that for a man. Not to mention 38 grams of fat, double your daily needs.
"Nobody expects a hamburger to be a health food, but they don't expect it to take up half of their daily calories," said Margo Wootan of the Center for Science in the Public Interest.
The new federal law applies to companies with 20 or more outlets. The question is: Will knowing the calorie counts influence what consumers order?
Panera Bread is the first big chain to post the calorie counts. It's found more people choosing the "Pick-Two" menu option which includes a soup and half a sandwich or half a salad.
"The customers that do care are getting smarter about their options and their picks and they're really figuring out what works best for them," said Pat Mellor of Panera Bread.
"The calorie count probably isn't going to change what I order, but it might increase my guilt quotient," said Dennis Laliberty.
In New York City, where calorie counts have been required for two years, it is making a modest difference. A Stanford study of Starbucks found the average calories per purchase fell from 247 to 232, a 6-percent drop.
"If you can get people to cut a few calories from their diet on average across the population, that can have a big impact," said Wootan.
Soon Americans will have no choice but to know White Castle's chocolate shake costs 820 calories. And ignorance is no longer an excuse.