How many calories in a grilled burger?

In the restaurant they have a big board with the nutrition facts. If you mean by double stack it's: 360 calories. If you mean the Double Jr. Cheeseburger Deluxe it's 390 calories. You can go check it out on the Wendy's website.
There are approximately 360 calories (26 carbohydrates) in a Wendy's double stack.