Maintenance Calories Calculator
Find out how many calories you need each day to keep your weight steady, plus a plan to lose or gain, your macros and how long it will take.
Your details
Your result updates as you type.
Add it to see roughly how many weeks it will take.
Your result
Fill in the form and your daily calories will show up here.
| Goal | kcal/day |
|---|---|
| Lose about 0.5 kg (1 lb) a week | 0 |
| Maintain weight | 0 |
| Gain about 0.5 kg (1 lb) a week | 0 |
| Macros for your target | Grams/day |
|---|---|
| Protein | |
| Carbs | |
| Fat |
| Daily limits | Grams/day |
|---|---|
| Fibre (at least) | |
| Added sugar (up to) | |
| Saturated fat (up to) |
| Split your target across the day | kcal |
|---|
Estimated with the Mifflin–St Jeor formula multiplied by your activity level. BMI does not show muscle mass, so treat it as a rough guide. If you are pregnant, breastfeeding, under 18 or managing a medical condition, speak with a doctor or dietitian.
How to Figure Out Maintenance Calories
Most people who search for how to figure out maintenance calories end up with a number from a calculator and no idea whether to trust it. That is a fair worry. A maintenance figure is an estimate, and the good news is that you can test it yourself in a few weeks with nothing more than a bathroom scale and a food log.
This guide shows both halves of the job: how to get a solid first estimate with a formula, and how to turn it into your real number using your own results. If you only want the quick estimate, the calculator above does the first half for you in a few seconds.
Step 1: start with your resting energy
Your body spends most of its daily energy just keeping you alive: breathing, pumping blood, repairing tissue and holding your temperature steady. That cost is your basal metabolic rate, or BMR, and it depends mainly on your body size, your age and your sex. For healthy adults, the Mifflin–St Jeor equation is one of the most dependable ways to estimate it.
Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161
If you measure in pounds and inches, divide your weight by 2.2 to get kilograms and multiply your height by 2.54 to get centimetres. Round as you go; at this stage a few calories either way make no practical difference.
Step 2: choose an activity factor you can defend
BMR only describes a person lying still all day. To get from there to maintenance calories, you multiply by a factor that reflects how much you really move. This is where most estimates go wrong, because people judge themselves by their workouts instead of their whole day. A person who trains for an hour but sits for the other fifteen waking hours is usually closer to “lightly active” than “very active”.
| Your typical week | Factor |
|---|---|
| Desk job, hardly any workouts | 1.2 |
| 1–2 short workouts a week | 1.4 |
| About 3 workouts a week | 1.6 |
| Intense training 4–5 days a week | 1.75 |
| Manual work or hard training every day | 2.0 |
| Elite athlete in full training | 2.4 |
When you are torn between two levels, pick the lower one. It is easier to add food later than to wonder why a plan built on an inflated number is not working.
Step 3: multiply, and see it with real numbers
Your estimated maintenance calories are simply BMR multiplied by your activity factor. Here is how that looks for two different people.
Sara is 28, weighs 65 kg, is 165 cm tall and does light exercise twice a week. Her BMR is 650 + 1,031 − 140 − 161, which is about 1,380 calories. Multiplied by 1.4, her estimated maintenance is about 1,932 calories a day.
Ali is 30, weighs 80 kg, is 178 cm tall and trains three times a week. His BMR is 800 + 1,112 − 150 + 5, which is about 1,768 calories. Multiplied by 1.6, his estimated maintenance is about 2,828 calories a day.
These are starting points. Two people with identical measurements can still differ by a couple of hundred calories a day because of muscle mass, genetics and how much they fidget, walk and stand without realising it. That is why the next step matters.
Step 4: test your number against your own body
This is the part most guides skip, and it is what turns an estimate into your actual maintenance level. Eat your estimated calories every day for two to three weeks and record two things.
- Your morning weight. Weigh yourself first thing, after using the bathroom and before eating or drinking. Daily readings jump around because of water and salt, so compare the average of week one with the average of the final week.
- Your food. Log everything, including cooking oil, sauces, snacks and drinks. Weigh food on a kitchen scale for at least the first week, because portion guesses are usually too low.
If your average weight stayed within a few hundred grams, your estimate was right. If it moved, correct it. As a rough rule, 1 kg of body weight is worth about 7,700 calories, so a change over 14 days tells you how far off you were each day.
| Weight change over 14 days | What happened | Your maintenance is about |
|---|---|---|
| Down 1 kg | About 550 kcal/day below maintenance | Average intake + 550 |
| Down 0.5 kg | About 275 kcal/day below | Average intake + 275 |
| No change | Eating at maintenance | Average intake |
| Up 0.5 kg | About 275 kcal/day above | Average intake − 275 |
| Up 1 kg | About 550 kcal/day above | Average intake − 550 |
Suppose you ate an average of 2,000 calories and gained 0.5 kg in two weeks. You were roughly 275 calories over maintenance, so your true figure is close to 1,725. Run the test once more at the new level and you will have a number you can trust.
Why your first estimate can be off
- Formulas assume an average body. Mifflin–St Jeor can miss by 10% or more for individuals. If you know your body-fat percentage and you carry a lot of muscle, the Katch–McArdle formula (BMR = 370 + 21.6 × lean body mass in kg) can suit you better, because it works from lean mass instead of total weight.
- Everyday movement is hard to see. Steps, standing, housework and fidgeting can differ by several hundred calories between two people with the same job title. A step counter gives you a more honest picture than a guess.
- Logging errors add up. Under-reporting food by even 10% turns a perfectly accurate formula into a result that looks wrong. If your tracking says you are at maintenance but your weight keeps rising, check portions before blaming your metabolism.
- The scale is noisy. One heavy morning after a salty dinner means nothing. Judge by weekly averages, and give any new number at least two weeks before changing it.
Keeping your number up to date
Your maintenance calories are not permanent. They fall as you lose weight and rise as you gain it, they shift when your training or job changes, and they drift down slowly with age. Recalculate after every 5 kg (10 lb) change in body weight or any lasting change to your routine, then repeat the two-week check if accuracy matters to you. If you are pregnant, breastfeeding, under 18 or managing a medical condition, general formulas may not fit, so speak with a doctor or dietitian first.
Frequently asked questions
Use a calculator for a quick estimate, such as the one at the top of this page, then confirm it by tracking your weight and food for two to three weeks. The estimate gets you close, and the tracking makes it personal.
They are reliable enough to start with but they can be off by 10% or more for some people. That is why testing against your own weight trend is worth the effort.
Mifflin–St Jeor is a good default for most adults. Katch–McArdle can be a better fit if you know your body-fat percentage and have a lot of muscle.
Plan on two to three weeks of consistent eating and daily weigh-ins. A shorter test is too easily distorted by water weight.
Slightly, but you do not need to eat a different amount every day. What counts is your average across the whole week.
This article is for general information only and is not medical advice. Speak with a doctor or registered dietitian before making major changes to your diet or exercise routine.