Updated
Maintenance Calorie Calculator
Your maintenance calories are the daily intake that holds your weight steady. This tool shows a range across three published equations, because they disagree.
Skip to the answerThese are example numbers — enter your own above.
Your maintenance calories, as a range across equations
Each equation's BMR × 1.2 for your activity level. Mean of the equations 2,157 kcal/day.
| Mifflin-St Jeor | 2,112 kcal |
|---|---|
| Revised Harris-Benedict | 2,202 kcal |
| Katch-McArdle | add body fat % to include it |
Is exercise already included? Yes. The “Sedentary” multiplier (×1.2) already covers your workouts and daily movement. Do not add calories burned in the gym on top of this number — double-counting exercise is the most common reason these estimates come out too high.
| Activity level | Factor | Maintenance |
|---|---|---|
| Sedentaryselected | ×1.2 | 2,112–2,202 kcal |
| Lightly active | ×1.375 | 2,420–2,523 kcal |
| Moderately active | ×1.55 | 2,728–2,844 kcal |
| Very active | ×1.725 | 3,036–3,165 kcal |
| Extra active | ×1.9 | 3,344–3,486 kcal |
Show the work
Each equation estimates your basal metabolic rate (BMR) — energy used at complete rest — from your sex, age, height and weight. Katch-McArdle instead uses lean body mass, which is why it needs a body fat percentage. Every BMR is then multiplied by your activity factor (×1.2) to reach maintenance calories. The range you see is the spread between equations, not a margin of error for your body.
Supported inputs: ages 18–80, height 130–230 cm (4 ft 3 in – 7 ft 7 in), weight 35–250 kg (77–551 lb), body fat 8–55% or blank. Imperial figures beside the fields are rounded; the exact limits are the metric ones. Results are shown in whole calories per day.
How maintenance calories are worked out
Every estimate starts with basal metabolic rate (BMR) — the energy your body spends at complete rest keeping your heart, brain, liver and kidneys running. For most adults this is roughly 60–70% of total daily energy use. BMR is then multiplied by an activity factor to account for everything else you do: walking, working, fidgeting and training.
The three equations here take different routes to BMR. Mifflin-St Jeor and the revised Harris-Benedict equation both work from sex, age, height and weight. Katch-McArdle ignores those and works from lean body mass instead, which is why it only appears when you supply a body fat percentage.
Why calculators disagree with each other
If you have tried three maintenance calorie calculators and got three different answers, nothing is broken. Two things drive the spread:
The equation. For a 30-year-old, 5′10″, 175 lb man, Mifflin-St Jeor and revised Harris-Benedict differ by roughly 90 calories a day before any activity adjustment — and that gap widens once a multiplier is applied.
The activity level. This is the bigger factor by far. Moving one step up the scale — from lightly active to moderately active — adds about 175 calories a day for a typical adult. Most people overestimate here. If your job is desk-based and you train three times a week, that is “lightly active” territory, not “very active”.
Picking your activity level honestly
A note on where these multipliers come from: the 1.2 to 1.9 scale is the conventional activity-factor scale associated with the Harris-Benedict tradition. Unlike the three BMR equations cited at the bottom of this page, these factors are a widely used convention rather than the product of a single validation study — which is part of why different calculators disagree. Each factor is meant to cover exercise and everyday movement together.
The descriptions on each option above are deliberately concrete. Read them as a description of your whole week, not of your best week. A useful check: if you cannot name the specific sessions or physical work that justify a level, pick the one below it. Starting low and adjusting upward from real weight data beats starting high and wondering why the scale is moving.
What this estimate can and cannot tell you
These equations were built to predict averages across groups of people. They describe a typical body with your sex, age, height and weight — not your body specifically, which can sit meaningfully above or below the prediction. That is the honest limit of any calculator on this subject, including this one.
One thing the arithmetic does say plainly: every equation here takes weight as an input, so the estimate changes when your weight changes. A number calculated at one weight does not describe you at another, so it is worth recalculating rather than holding on to an old figure.
For advice on how to act on any of this — what to eat, how to change intake, or how to interpret changes on the scale — talk to a clinician or a registered dietitian. This page deliberately stops at the estimate.
Who this calculator is for
These equations were developed and validated in healthy adults — the Mifflin-St Jeor study covered 498 people aged 19 to 78. This tool accepts ages 18 to 80 and is intended for healthy, non-pregnant, non-breastfeeding adults.
It is not appropriate during pregnancy or breastfeeding, for children or teenagers, for athletes with unusual training loads, or for anyone with a condition affecting metabolism, and it is not a tool for managing an eating disorder. If any of those apply, the right number comes from a clinician or registered dietitian, not from a web page.
Frequently asked questions
What are maintenance calories?
Maintenance calories are the number of calories that keep your weight steady — the energy your body uses in a day, including basic organ function, daily movement and exercise. Eat that number and your weight holds; eat consistently below or above it and your weight moves.
Is exercise already included in this number?
Yes. The activity multiplier is applied to your basal metabolic rate and is meant to cover both workouts and everyday movement. Adding calories burned during exercise on top of this estimate double-counts them, which is the most common reason people end up eating more than they intended.
Why do different maintenance calorie calculators give different answers?
Two reasons. First, they use different equations — Mifflin-St Jeor, Harris-Benedict and Katch-McArdle can differ by a few hundred calories for the same person. Second, activity multipliers are coarse: the gap between 'lightly active' and 'moderately active' is about 175 calories per day for a typical adult, and people routinely pick a level higher than their real week.
Which equation should I use?
Mifflin-St Jeor is generally the default for healthy adults and is the equation most dietitians reach for. If you know your body fat percentage from a reliable measurement, Katch-McArdle can suit lean or very muscular people better because it works from lean body mass. This page shows all of them so you can see the spread rather than trusting one number.
How accurate is a maintenance calorie estimate?
It is a starting point, not a measurement. These equations were built to predict averages for groups, so any individual can sit meaningfully above or below the estimate — which is why this page shows the spread between equations rather than a single figure. For guidance on what to do with the number, speak to a clinician or registered dietitian.
Do my maintenance calories change as I lose or gain weight?
Yes. Every equation on this page takes weight as an input, so the estimate moves when your weight moves — a lighter body needs fewer calories to maintain. Recalculate as your weight changes rather than holding on to your starting number.
How this page is made
Medical review: pending. The equations below are published, peer-reviewed academic formulas, and this implementation of them is verified by automated tests against independently hand-computed reference values. A credentialed reviewer has not yet checked the guidance on this page, and we say so here rather than implying a review that has not happened.
This calculator provides general information, not medical or nutritional advice. It does not diagnose or treat any condition. Talk to a qualified clinician or registered dietitian before making significant changes to what you eat.
Sources
- Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition, 1990;51(2):241–247. PubMed
- Roza AM, Shizgal HM. The Harris Benedict equation reevaluated: resting energy requirements and the body cell mass. American Journal of Clinical Nutrition, 1984;40(1):168–182. PubMed
- Katch-McArdle formula: BMR = 370 + 21.6 × lean body mass (kg). McArdle WD, Katch FI, Katch VL. Exercise Physiology: Nutrition, Energy, and Human Performance.
- Weight-loss calorie ranges referenced in the low-result note follow NHLBI guidance for adults with overweight or obesity. NHLBI