Enery kCals

In common usage, they're one and the same. There's nothing to convert when logging your nutrition.

In scientific circles, there are actually 2 measures: the gram calorie and kilogram calorie (kCal). If you're wearing a lab coat and playing with beakers and bunsen burners, when you say "calorie" you probably mean a gram calorie . If you're wearing lycra and looking at the back of a Clif bar wrapper, when you say "calorie" you mean kilogram calorie.