Calorie Deficit Formula Explained, With Examples
Every calorie deficit result comes from one formula. Once you understand what goes into it, you can sanity-check any figure you are given, whether by an employer, a bank, a teacher or another website.
The formula
1 kg of fat ≈ 7,700 kcal; daily deficit = weekly loss × 7,700 ÷ 7.
What each input means
- Your TDEE (kcal): the value you enter in the calculator.
- Target weight loss per week (kg): the value you enter in the calculator.
Example
For example, with these inputs:
- Your TDEE (kcal): 2,200
- Target weight loss per week (kg): 0.5
the calculator returns:
- Daily calorie target: 1,650 kcal
- Daily deficit: 550 kcal
How the result changes
The table keeps the other inputs at their example values and changes your tdee (kcal).
| Your TDEE (kcal) | Daily calorie target | Daily deficit |
|---|---|---|
| 2,200 | 1,650 kcal | 550 kcal |
| 1,100 | 550 kcal | 550 kcal |
| 1,650 | 1,100 kcal | 550 kcal |
| 2,750 | 2,200 kcal | 550 kcal |
| 3,300 | 2,750 kcal | 550 kcal |
Why it matters
Health numbers are most useful when you track them consistently. A quick calculation turns everyday measurements into something you can act on, whether that is planning meals, training for a run or preparing for a clinic visit.
Energy needs depend on age, sex, size and activity. Formulas such as Mifflin-St Jeor estimate resting needs, and an activity multiplier turns that into daily needs. Real requirements vary by a few hundred calories, so adjust based on how your weight changes over several weeks.
Singapore's tropical climate means you lose more fluid through sweat, even when you are not exercising. Thirst, urine colour and how you feel are good guides, and needs rise during outdoor activity or heat waves.
Research has shown that Asians tend to develop conditions such as type 2 diabetes and heart disease at lower body weights than Europeans. That is why the Health Promotion Board recommends lower BMI cut-offs for Singaporeans, with 23 marking the start of moderate risk.
Related calculations
- Heart Rate Zone Calculator: Shows heart-rate training zones from your age.
- Waist-to-Height Ratio Calculator: A ratio above 0.5 suggests increased health risk.
- Protein Intake Calculator: Estimates daily protein needs.
- Steps to Kilometres Calculator: Converts step counts (like your Healthy 365 tracker) to distance.
Use the Calorie Deficit Calculator to plug in your own numbers.
Run your own numbers: Calorie Deficit Calculator