What is the calorie count in a roll?

702551 is right about the need to figure out your own nutritional values for most recipes on the internet.
However, when I'm in a rush and need to decide on something, I often search and find a similar recipe and use their nutritional values if I need to make a decision - will the dish fit in a menu I'm planning, or for a person with special dietary needs.
One site that usually has nutritional values is allrecipes. There are others, but I haven't seen them often enough to say.

Most of the recipes here are offered by community members. If the recipe doesn't have nutritional information you're going to have to plug the ingredients into a nutritional calculator. This is not specific to Food52; most online recipe sites don't include nutritional information.

The thread below yours mentions one such online nutrition calculator tool.

It's best for you to bookmark at least one nutritional calculator site since you'll probably want to do this again whether it's for an online recipe or one in a deadtrees cookbook.

Best of luck.