have used?

Not sure if it matters, but I don't need to lose weight. I want to track my calories because I need a better mix of protein and carbs. I am going to ramp up my exercise routine and I have watched some videos where people have increased exercise and reduced calories only to find they lost muscle mass. I don't want to lose muscle mass, not that I have much, but I exercise and still look skinny fat. I hate this. I am tall and skinny by nature and running is my easy go to exercise. I need to change this up and want to make sure my calorie intake is correct.