How to Work Out Your Maintenance Calories Properly
Your maintenance calories are the amount of energy you eat in a typical day when your body weight holds steady over a few weeks. The proper way to find the number has two stages. First, estimate it with a recognised equation and an honest activity multiplier. Second, test that estimate against reality: eat a consistent amount for two to three weeks, log your weight every morning, and adjust based on the trend. The calculator gives you a guess. Your own scale weight, averaged over time, gives you the answer. Everything below explains how to do both stages without fooling yourself.
What “maintenance” actually includes
Maintenance is often called TDEE, total daily energy expenditure. It is the sum of four things, and knowing them explains why two people of the same height and weight can have quite different numbers.
- Basal metabolic rate (BMR). The energy needed to keep you alive at rest. For most people it is the largest single part.
- The thermic effect of food. Digesting food costs energy. Protein costs more to process than carbohydrate or fat.
- Exercise. Your training sessions. Usually smaller than people assume, even for those who train four times a week.
- Non-exercise activity. Walking to the station, standing, fidgeting, carrying shopping. This varies enormously between people and from week to week. We cover it in more detail in NEAT explained.
The practical point: a desk-bound week of working from home and a week of walking between meetings in the City can differ by several hundred calories a day, with identical gym sessions.
Stage one: estimate it
For a population average, the NHS gives round figures of around 2,500kcal a day for men and 2,000kcal a day for women, while noting that individual needs vary with age, size and activity (NHS: understanding calories). That is fine for a food label. It is too blunt for planning your own intake.
A better starting point is the Mifflin-St Jeor equation, which is the one most dietitians and decent online calculators use for BMR:
- Men: (10 x weight in kg) + (6.25 x height in cm) - (5 x age in years) + 5
- Women: (10 x weight in kg) + (6.25 x height in cm) - (5 x age in years) - 161
Then multiply BMR by an activity factor:
| Your typical week | Multiplier |
|---|---|
| Desk job, little walking, no structured training | 1.2 |
| Desk job, some walking, training 1-3 times a week | 1.375 |
| On your feet a fair amount, training 3-5 times a week | 1.55 |
| Physical job or hard training most days | 1.725 |
A worked example: a 42-year-old man, 82kg, 180cm. BMR is 820 + 1,125 - 210 + 5 = 1,740kcal. He sits at a desk, walks to Highgate station and back, and trains twice a week, so 1.375 is honest. His estimate is about 2,390kcal.
The most common mistake at this stage is choosing the multiplier you would like rather than the one you live. Two hard sessions a week do not make a “very active” person if the other 166 hours are spent sitting. When in doubt, pick the lower band. Equations also carry real error for any individual, often a couple of hundred calories either way, which is why stage two exists.
What about a body composition scan?
An InBody report includes an estimated BMR based on your measured lean mass. For someone carrying a lot of muscle, or a lot of fat, that can be a more sensible starting point than a height-and-weight formula. It is still an estimate of resting energy, not maintenance, so you still apply a multiplier and still test it. If you have a scan, read how to read your InBody results for what the other numbers mean.
Stage two: test it against your own weight
This is where most people skip ahead, and where the useful information is. The method is simple but asks for some discipline.
- Eat your estimated number every day for 14 to 21 days. Not exactly, but within about 100kcal on average. Weekends count. A Friday dinner in Crouch End and a Sunday roast are part of the data, not a holiday from it.
- Weigh yourself every morning after the loo, before food or drink, wearing the same thing. Write it down.
- Ignore individual days. Daily weight can swing by a kilo or more from salt, carbohydrate, alcohol, sleep and, for many women, the menstrual cycle. Our post on water weight fluctuations covers why.
- Compare weekly averages. Week three’s average against week one’s is the number that matters. Week one often contains noise from changing how you eat.
- Adjust. If the average is stable (within roughly 0.2kg), you have found maintenance. If it is moving, adjust using the rule below and run another fortnight.
The adjustment rule of thumb
A commonly used approximation is that a kilogram of body fat holds around 7,700kcal. It is not exact, because early weight change includes water and glycogen, but it is good enough for a sensible correction. If your weekly average drifts down by 0.3kg a week while eating your estimate, your true maintenance is roughly 300kcal a day higher (0.3 x 7,700, divided by 7). If it drifts up by the same amount, it is roughly 300kcal lower.
Make the change, then test again. Two rounds is usually enough to get within a useful margin.
The mistakes that make the number wrong
- Tracking accurately on weekdays and estimating at weekends. The weekend is where most of the missing calories live. See weekend overeating if this sounds familiar.
- Not counting cooking oil, milk in coffee and drinks. A generous pour of olive oil is easily 100kcal. Three flat whites are a small meal.
- Testing during an unusual fortnight. A week away, a heavy work deadline or a cold will distort both intake and activity. Pick an ordinary stretch.
- Changing training at the same time. Starting a new programme in the same fortnight muddies the data. Keep your activity roughly constant while you test.
- Treating the result as permanent. Maintenance moves when your weight, activity or job changes. Retest after any meaningful change, and after a fat loss phase.
Why bother finding it at all?
Because every other nutrition decision is relative to it. A fat loss phase is a planned amount below maintenance, which is what our guide to what a calorie deficit is builds on. A muscle-building phase is a modest amount above. Without a tested maintenance figure, you are setting targets relative to a guess, and when progress stalls you cannot tell whether the plan is wrong or the starting number was.
It also matters at the end of a diet. People who have just lost weight often have no idea what they can eat to stay there, so they drift back up. A known maintenance number, retested at the new weight, gives you a landing point.
How we handle this in the studio
When someone starts private 1-1 training in Highgate, we usually take an InBody reading in the first session, run the equation, and agree a two to three week testing period before setting any deficit. It feels slower than jumping straight to a diet. In practice it saves months, because the targets are built on your numbers rather than a calculator’s.
If you have a medical condition, are pregnant, take medication that affects appetite or weight, or have a history of difficult eating, check with your GP before changing how much you eat.
Questions we get asked
Should I eat back the calories my watch says I burned?
No. Fitness trackers often overestimate exercise energy. Set a fixed daily target that already includes your typical training, and let the weight trend tell you if it is right.
Is maintenance the same on training and rest days?
Not quite, but averaging across the week is simpler and works just as well for most people. Some prefer a little more food on training days; the weekly total is what counts.
How accurate does my tracking need to be?
Consistent matters more than perfect. Weigh foods you eat often for the testing period, use the same app entries, and be honest about extras. Small errors that repeat every day are fine because the weight trend absorbs them.
Can a personal trainer work this out for me?
A good one will help you estimate and test it, then use it to plan your eating around your training. See our personal training page for how coaching at the studio works.
Book with The Highgate House
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