Energy and weight
How do I estimate my maintenance calories?
Maintenance calories are the intake that supports a broadly stable body weight over time. A formula provides a starting estimate, not a measurement. Your activity assumption and the quality of your records matter as much as the arithmetic.
Sources: NIDDK: Body Weight Planner
Resting is not the whole day
Resting energy expenditure describes energy use at rest. Total daily expenditure also includes activity and the energy cost of processing food. Entering a resting estimate as a daily food target confuses two different quantities.
The Mifflin–St Jeor equation was developed using measurements from 498 healthy adults aged 19–78. A population equation can miss an individual. It does not account directly for your recent training, illness, or changing routine.
Sources: Mifflin et al. (1990): predicting resting energy expenditure; NIDDK: Body Weight Planner
What this calculator does
The public equation is 10 × weight in kg + 6.25 × height in cm − 5 × age, then +5 for the male equation or −161 for the female equation. Those categories belong to the original research; they do not capture every person’s physiology. If neither is suitable, showing both illustrates the difference, not your uncertainty interval.
We multiply the resting estimate by an activity assumption you choose. NIDDK describes typical activity levels from 1.4 to 2.5. Combining that assumption with this resting equation is a simple educational illustration, not the NIDDK dynamic model and not POWR’s personalized target calculation.
Sources: Mifflin et al. (1990): predicting resting energy expenditure; NIDDK: Body Weight Planner
Change the assumption, change the answer
Suppose a resting estimate is 1,600 kcal/day. Multiplying by 1.4 gives 2,240; multiplying by 1.8 gives 2,880. The 640-calorie difference comes entirely from the assumed activity level. Neither result proves what that person burns.
This is why two calculators can disagree without either doing the multiplication wrong. Compare their inputs and assumptions before averaging their answers.
| Resting estimate | Activity assumption | Daily estimate |
|---|---|---|
| 1,600 kcal/day | 1.4 | 2,240 kcal/day |
| 1,600 kcal/day | 1.8 | 2,880 kcal/day |
Use it as a question to check
If weight tracking is appropriate for you, compare readings collected under similar conditions instead of treating a single morning as a verdict. Keep incomplete food records visibly incomplete rather than pretending they represent a full day.
A clinician or dietitian can help when illness, medication, pregnancy, breastfeeding, a prescribed diet, or an eating-disorder history changes the question. The tool below is not for those situations. It does not set a deficit, diagnose metabolism, or promise a future weight.
Try the public method
Maintenance calorie illustration
Estimate resting needs, then see the effect of an activity assumption. This is not a recommended intake or a weight-loss target.
Inputs and results stay in this page. No account, saving, or calculator analytics. These tools are separate from POWR’s app targets.
Supported inputs are a tool boundary, not proof of suitability. Height: 120–230 cm. Weight: 30–300 kg (about 66–661 lb). For values outside the supported range or an excluded situation, seek individual guidance.
Sources and limits
These sources support the claims beside which they are linked. Practical checklists and invented examples are POWR’s educational interpretation, not findings from a trial of the app.
- NIDDK: Body Weight Planner
Public planning tool with activity assumptions and population exclusions. Our simple illustration does not reproduce its model.
- Mifflin et al. (1990): predicting resting energy expenditure
Original equation study in 498 healthy adults aged 19–78. Predicts resting expenditure, not total daily needs.
- NHS England: how to record your weight (PDF)
Practical guidance on consistent weighing conditions, not a requirement to weigh daily.
This guide was prepared by POWR. It has not received an independent clinical review. It does not diagnose, treat, or replace care from a qualified professional.
Found an error? Send the page, claim, and a supporting source, without personal health records. Read our approach to evidence and corrections.