There isn't a one-size-fits-all answer to what the healthiest fast food burger is, though size does matter. Registered dietitians suggest remaining mindful of toppings, nutrients and what else you're ordering with your burger.

A survey conducted by Delish, the foodie site known for “recipes that get people excited to cook,” determined the healthiest hamburgers at major North American chains.

We scoured fast food menus to find the most expensive burgers in the U.S., and Five Guys, Shake Shack, Carl's Jr. and more chains topped the list.