Resting energy
BMR / RMRCore processes such as breathing, circulation, temperature control and organ function.
BMR uses strict test conditions. RMR uses less strict resting conditions and is usually slightly higher.
Often roughly 60–70%
Nutrition
10 min read
A useful target starts with a clear goal
You do not need a perfect calorie number. You need a sensible starting point that matches what you want to achieve now, is realistic enough to follow, and can be refined using your own progress.
The short answer
Start with a useful range, not a supposedly perfect number.
Match the estimate to your current goal, follow it consistently, then let three weeks of average weight, hunger, training and recovery tell you whether anything needs to change.
The useful principleEstimate → test → adjust
The calculator gets you moving. Your real trend makes the estimate personal.
Where your daily energy estimate comes from
Total daily energy expenditure (TDEE) is an estimate of all the energy your body uses across a day. It gives you a practical place to start, not a number your body must match perfectly.
The breakdown below shows how resting needs, everyday movement, planned exercise and processing food contribute to that total. It also explains why basal metabolic rate (BMR) and resting metabolic rate (RMR) are useful reference points but are not the same as maintenance calories.
The calculator combines an estimated resting requirement with an activity factor to produce a starting TDEE. Use it for speed, then use your own trend for accuracy. About three reasonably consistent weeks of calorie intake, weekly-average body weight and training feedback will tell you whether the estimate fits your real life.
Choose your current direction
Choose the outcome that matters most now. The calculator will turn that direction into a practical starting range. You can change phase later when your priority changes.
Fat loss: use a controlled deficit
Begin around 250 to 600 calories below your current best maintenance estimate. Start at the highest intake that still creates a useful downward trend while allowing you to train, recover and live normally.
Maintenance or recomp: start near maintenance
Start around your current best maintenance estimate. For recomposition, judge progress using waist, photos, clothing fit and training performance as well as body weight.
Muscle gain: use a small surplus
Begin around 150 to 300 calories, or roughly 5–10%, above your current best maintenance estimate. Start near the lower end and look for a slow upward trend alongside progressive training.
Run a three-week experiment
Compare weekly-average body weight rather than one weigh-in. Review waist or other measurements, hunger, energy, training performance and recovery. Check consistency first, including weekends, oils, sauces, drinks, snacks and unlogged extras.
Adjust only when the trend justifies it
Change the daily target by around 100 to 200 calories, then hold the new intake for another three weeks. Do not automatically eat back exercise calories reported by watches or machines, and avoid reacting to a few unusual weigh-ins.
Common mistakes
Common mistakes
Open a card to see the correction before changing your calorie target.
01Treating a calculator estimate as exact
A calculator is a starting point. Your real intake, average weight trend and performance decide whether it fits.
02Choosing calories before choosing a goal
A deficit, maintenance target and surplus serve different outcomes. Choose one current priority first.
03Using the largest possible deficit or surplus
More aggressive is not automatically more effective. Use the smallest change that creates the intended trend while supporting training and adherence.
04Missing weekends and extras
Oils, sauces, drinks, snacks, larger portions and untracked weekends can erase the planned difference. Check consistency before reducing calories.
05Reacting to one weigh-in
Water, digestion, sodium and carbohydrate intake can move body weight quickly. Compare weekly averages.
06Eating back exercise calories
Watches and cardio machines can overestimate expenditure. Do not automatically add those calories to the target.
07Changing several things together
Make one adjustment at a time so you can tell what affected the result.
Practical checklist
Your three-week setup checklist
Three phases keep the test simple enough to learn from.
Set the direction
- Choose one current priority
- Estimate maintenance
- Choose the smallest useful calorie change
Track useful signals
- Track intake consistently
- Compare your weekly average
- Record hunger, energy, training and recovery
Review and adjust
- Review after at least three weeks
- Adjust by 100–200 calories if needed
- Make one adjustment at a time
PERSONALISED SUPPORT
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