Advanced Calculator
Example Data Table
| Person | Age | Weight | Height | Activity | Estimated Maintenance |
|---|---|---|---|---|---|
| Office worker | 34 | 72 kg | 172 cm | Light | About 2,180 kcal/day |
| Gym trainee | 28 | 82 kg | 180 cm | Moderate | About 2,900 kcal/day |
| Heavy labor | 40 | 90 kg | 178 cm | Very active | About 3,500 kcal/day |
Formula Used
Mifflin St Jeor male: BMR = 10W + 6.25H - 5A + 5
Mifflin St Jeor female: BMR = 10W + 6.25H - 5A - 161
Revised Harris Benedict male: BMR = 88.362 + 13.397W + 4.799H - 5.677A
Revised Harris Benedict female: BMR = 447.593 + 9.247W + 3.098H - 4.330A
Katch McArdle: BMR = 370 + 21.6 × lean body mass in kg
Maintenance calories: ((BMR × activity factor) + exercise calories + thermic effect) × adjustment factor
W means weight in kg. H means height in cm. A means age.
How To Use This Calculator
Choose your unit system first. Enter sex, age, height, weight, body fat, and activity level. Add average exercise calories if you track them. Keep thermic effect near 10% for a balanced diet. Use adjustment only when you need a planned correction. Press the submit button to see the result above the form.
Understanding Calorie Maintenance
Calorie maintenance is the daily energy intake that keeps body weight stable. It links biology with physics. Food supplies chemical energy. The body spends that energy through rest, movement, heat, repair, and digestion. When intake matches total expenditure, stored body mass stays almost unchanged.
Why This Calculator Helps
This calculator estimates maintenance calories with several recognized equations. It can use Mifflin St Jeor, revised Harris Benedict, or Katch McArdle. Each method starts with basal metabolic rate. Then it adds activity, exercise, thermic effect, and safety adjustments. The result gives a practical target for steady weight control.
Energy Balance View
Physics treats calories as energy units. One dietary calorie equals one kilocalorie. Weight change happens when energy intake and energy output differ over time. A surplus stores energy, mostly as fat or lean tissue. A deficit removes stored energy. Maintenance is the balance point between these flows.
Important Inputs
Age, sex, height, weight, and body fat all affect the estimate. Activity level can change the answer greatly. A desk worker and a laborer may need very different intakes. Exercise calories also matter, but they are often overestimated. Small adjustments give better tracking results.
Using The Result
The output is a starting point, not a fixed rule. Track average weight for two to four weeks. Use similar weigh in times. Watch waist changes, strength, hunger, and energy. If weight trends upward, reduce intake slightly. If weight drops, add a small amount.
Better Planning Tips
Protein, fiber, sleep, and routine meals support accuracy. Liquid calories can hide large energy amounts. Weekend eating may change weekly averages. The best target is one you can follow consistently. Use the downloadable report for records, coaching notes, or client reviews.
Reading The Numbers
Maintenance needs are not identical every day. They move with steps, training load, stress, temperature, and recovery. Use the weekly average as the main guide. A range is often better than one exact number. The low end suits quiet days. The high end suits active days.
Limits And Accuracy
All equations are estimates. Medical issues, medication, pregnancy, growth, and athletic training can change needs. For clinical concerns, ask a professional. For planning, update inputs when weight, body fat, or activity changes.
FAQs
What are maintenance calories?
Maintenance calories are the daily calories that keep your body weight stable. They match your energy intake with your energy use across rest, movement, digestion, and exercise.
Which equation should I choose?
Mifflin St Jeor is a strong general choice. Katch McArdle is useful when body fat is known. The average option can smooth differences between equations.
Is body fat required?
No. It improves the Katch McArdle estimate. If you do not know it, enter a reasonable estimate or use another equation.
Why add exercise calories separately?
Some people track workouts directly. Adding exercise calories helps separate normal activity from planned training. Use conservative values because devices can overestimate burn.
What is thermic effect?
Thermic effect is energy used to digest and process food. A common estimate is near 10% of intake, but diet composition can change it.
How often should I update the result?
Update the result when weight, activity, training, or body composition changes. For steady routines, review it every few weeks.
Can this calculator help with weight loss?
Yes. First find maintenance calories. Then create a modest deficit from that number. This page focuses on stable weight planning.
Is the result medically exact?
No. It is an estimate for planning. Medical conditions, medication, pregnancy, and growth can change calorie needs. Ask a professional for clinical advice.