Estimate how many calories you may need each day to maintain your weight. You can also see simple calorie targets for gradual weight loss or weight gain.
Maintenance calories
Estimate calories to stay around the same weight.
Goal targets
See calorie ranges for loss, maintenance and gain.
Metric or imperial
Use kg/cm or stones, pounds, feet and inches.
Calorie needs guide
Your daily calorie needs are an estimate of how much energy your body uses in a typical day. This includes energy used to keep you alive at rest, plus energy used for movement, exercise, digestion and normal daily activities.
This calculator estimates your basal metabolic rate using the Mifflin-St Jeor equation, then applies an activity multiplier to estimate your total daily energy expenditure. This is often shortened to TDEE.
The calculator estimates your basal metabolic rate using age, sex, height and weight. BMR is the starting point because larger bodies, taller bodies and younger bodies often use more energy at rest.
Your BMR is multiplied by an activity factor. This estimates your total daily energy use, including work, walking, chores, training and other movement.
Activity levels
Activity level is one of the easiest places to overestimate. Think about your average week, not your best week. If you are between two levels, choosing the lower one may give a more realistic starting estimate.
| Activity level | Factor | Description |
|---|---|---|
| Sedentary | 1.2 | Mostly sitting, little planned exercise. |
| Lightly active | 1.375 | Light exercise, walking or active daily routine 1–3 days per week. |
| Moderately active | 1.55 | Moderate exercise or active job around 3–5 days per week. |
| Very active | 1.725 | Hard exercise, sports or physically demanding work most days. |
| Extra active | 1.9 | Very hard training, endurance work or highly physical job. |
Your calculated maintenance calories are a starting estimate. After using a target for 2 to 4 weeks, your real-world weight trend, hunger, energy levels and training performance can help you decide whether to adjust.
| Goal | Starting target | Notes |
|---|---|---|
| Maintain weight | Estimated maintenance calories | Useful as a starting point if your weight is broadly stable. |
| Slow weight loss | Maintenance minus about 300 kcal/day | A gentler deficit that may be easier to sustain. |
| Moderate weight loss | Maintenance minus about 500–600 kcal/day | Often used for steady weight loss, but individual needs vary. |
| Gradual weight gain | Maintenance plus about 250–500 kcal/day | Commonly used when trying to gain weight or build muscle. |
Formula-based estimates cannot fully account for genetics, muscle mass, hormones, medication, health conditions, sleep, stress and daily movement.
Food quality matters too. Protein, fibre, fruit, vegetables, wholegrains and healthy fats can affect fullness, health and long-term adherence.
Body weight naturally fluctuates. Look at the trend over several weeks rather than changing your target based on one or two weigh-ins.
Practical advice
Treat your result as a starting point, not a rule. If your weight is stable for several weeks, your real maintenance intake is probably close to what you are currently eating. If your weight is changing, your real energy balance is different from your estimate.
Daily calorie needs are an estimate of how many calories your body uses in a day. This includes energy used at rest, digestion, movement and exercise.
Maintenance calories are the estimated number of calories you need each day to keep your weight broadly stable, assuming your activity level stays similar.
BMR stands for basal metabolic rate. It is an estimate of how many calories your body uses at rest for essential functions such as breathing, circulation and cell repair.
This calculator estimates BMR using the Mifflin-St Jeor equation, then multiplies it by an activity factor to estimate daily maintenance calories.
A common approach is to create a moderate calorie deficit. NHS guidance says the average person trying to lose weight should aim to reduce daily calorie intake by about 600 kcal. Individual needs can vary.
For gradual weight gain, some people use a small calorie surplus, such as 250 to 500 kcal above maintenance. The right amount depends on your goal, training, appetite and health.
It is an estimate, not a precise measurement. Real calorie needs vary because of body composition, genetics, hormones, health conditions, medication, daily movement and tracking accuracy.
Speak to a GP, dietitian or qualified healthcare professional if you are pregnant, under 18, have an eating disorder or suspected eating disorder, have a medical condition, are losing weight unexpectedly, or plan a very low-calorie diet.
Check your BMI category and estimated healthy weight range.
Check whether your waist size is less than half your height.
Check common eligibility factors for weight-loss treatment discussion.
Review lifestyle and health factors linked with heart risk.
This page provides general health information and should not replace advice from a GP, pharmacist, dietitian or other qualified healthcare professional.
The calculator uses the Mifflin-St Jeor equation to estimate BMR and applies an activity multiplier to estimate maintenance calories. Calorie guidance should be reviewed against current public health and clinical advice before publication.
NHS guidance on calories, average daily needs and why needs vary.
NHS guidance on calorie counting and reducing intake for weight loss.
Reference table including the Mifflin-St Jeor resting metabolic rate equation.
Last reviewed by AllHealthandCare editorial team: May 2026. Next review due: May 2027.