How Many Calories Do I Need Each Day?

Your daily calorie requirement is shaped by two main things: how much energy your body burns just to keep functioning (your basal metabolic rate), and how much additional energy you use through movement and activity. Together, these give a figure often called your total daily energy expenditure (TDEE).

Key factors that influence daily calorie needs

• Body size and composition: larger bodies and those with more muscle mass generally burn more calories at rest.
• Age: metabolic rate tends to slow gradually over time, meaning calorie needs often decrease with age.
• Activity level: someone with a physically active job or regular exercise routine will burn significantly more calories than someone who is mostly sedentary — often several hundred calories more per day.
• Biological sex: on average, males tend to have higher calorie requirements than females, largely due to differences in muscle mass.
• Current goals: whether you are aiming to lose weight, maintain your current weight, or gain weight will determine the right calorie target relative to your TDEE.

General reference ranges

As a broad educational guide, many adults require somewhere in the range of 1,600–2,500 calories per day to maintain their current weight, depending on the factors above. To lose weight gradually, many people eat somewhat below this level; to gain weight, somewhat above it. These are general figures only — your own needs may fall outside this range, and the right target for you is something to discuss with your prescriber or a registered dietitian.

If you want to explore calorie goals in more detail, our guide on understanding calories on a GLP-1 journey covers the fundamentals, and you can find a more personalised breakdown using our daily calorie needs guide.

How GLP-1 medicines can change your calorie picture

Many people taking Mounjaro or Wegovy report a noticeably reduced appetite and lower food noise, which naturally leads to eating less. This is worth being aware of because eating too little — particularly of protein — can make it harder to preserve muscle and sustain energy. Tracking what you actually eat each day helps you stay within a range that supports your goals without going too far in either direction. For more on calorie targets specifically for weight loss, see our page on how many calories to eat to lose weight.

Knowing your approximate calorie target is one thing — consistently hitting it is another, especially when appetite fluctuates on a GLP-1 medicine. GLP Trackr's AI food photo scan makes logging what you eat effortless: point your camera at a meal and get an instant calories and protein breakdown, no manual entry needed.

Once you have set a daily calorie target in the app, the food log tracks your intake throughout the day and shows you where you stand at a glance. The app also lets you set a protein goal alongside your calorie goal, which matters on a GLP-1 journey when total food volume is lower and getting enough protein becomes even more important.

Over time, the insights feature helps you see patterns — for example, whether the days you hit your calorie and protein targets correlate with better energy or more consistent progress. That kind of personal data is genuinely useful to bring to an appointment with your prescriber or a dietitian.

For a broader look at calorie balance and how a deficit supports weight loss, visit our hub on understanding your calorie deficit.

The calorie figures and ranges on this page are general educational information. Your personal calorie needs depend on your individual circumstances — always follow the guidance of your prescriber, doctor, or a registered dietitian when setting targets, particularly while on prescription medication.

Ready to start logging? GLP Trackr is free to try for 7 days — download it on the App Store or Google Play and see how effortless calorie tracking can be when your phone does most of the work.