Guides
Straight answers to the questions people ask before they start tracking. No hype, no miracle claims — just the arithmetic, its limits, and what to do with it.
How many calories should I eat a day? The honest answer is that it depends on your body and how much you move — but the arithmetic is simple, and you can have a working number in about thirty seconds. → What is a calorie deficit? It is the reason every diet that works, works — whether it counts calories, cuts carbs, or shortens your eating window. → How accurate is AI photo calorie counting? Accurate enough to be useful, not accurate enough to be a laboratory measurement — and for changing your weight, that distinction matters less than most people assume. →
Estimates, not medical advice
This article is general information, not a diagnosis, treatment, or a substitute for professional advice. Energy needs vary with body composition, medication, and health conditions. Talk to a doctor or registered dietitian before making significant dietary changes, especially if you are pregnant or breastfeeding, under 18, or managing a medical condition or eating disorder.
See the science and sources behind our numbers →