So, if a 125 pound person who is moderately active would need about 1,875 calories per day. So, in reading this please keep in mind that it's only an estimate. Two people of the same weight may need two different calorie intakes. If one has more muscle in their body than fat, that person will burn up more calories. As mentioned, males need higher calories than women and genetics plays a role in this also.
Some people have a higher metabolic rate than others.