Ruthxxx is correct.

Those are the two best ways to go about it.
If it's not home made you can make a guesstimate. Chili tends to be higher calorie, especially with meat. Soups can be lower if it's broth based and has mostly veggies, but account for higher calories in soups with potatoes, noodles, chicken...
Soups with a cream base are generally higher calorie.
I usually buy it canned or I make it myself, but I have gotten soups at restaurants and you can either google the calories or estimate based on the type of soup/chili.
