How Many Calories Should I Eat a Day?

There is no single number that fits everyone — daily calorie needs typically range from roughly 1,600 to well over 3,000 kcal depending on your body size, age, sex and how much you move. What matters is your number, and it can be estimated in under a minute from a few details.

What determines your calorie needs?

Your body burns energy just existing — the basal metabolic rate, driven mostly by body weight, height, age and sex. On top of that comes everything you do: walking, training, even digesting food. Together they form your total daily energy expenditure (TDEE): the calories that keep your weight stable.

Adjusting for your goal

• Lose weight — eat below your TDEE. A modest deficit is sustainable and protects muscle and energy.
• Maintain — eat at your TDEE and use tracking to stay aware.
• Gain weight or muscle — eat slightly above your TDEE; for muscle gain, a lean surplus with a higher protein target works better than "eat everything".
• Custom — if you work with a coach or know your numbers, set your own calorie and macro targets directly.

Do you have to calculate this yourself?

No. CalorieAI's onboarding wizard does it in three steps: pick your goal, enter your details, and get a personal daily calorie target plus matching protein, carb and fat targets. All four goal types above are built in, including a fully custom option.

The target is a starting point, not a verdict

Every formula is an estimate. The real feedback loop is simple: log consistently for a few weeks, watch your weekly average weight, and adjust the target a little if the trend doesn't match your goal. That combination — a sensible starting number plus real-world data — beats any calculator on its own.

Note: this article is general information, not medical advice. Consult a qualified professional before making significant dietary changes.

Want to try it yourself? Download CalorieAI free on Android and log your next meal with a single photo.