The toolbox · Health
How many calories do you need?
Enter a few details and see the calories your body burns in a day — plus exactly how much to eat to lose, maintain or gain weight. Updates as you type.
- More than one number. Your BMR, daily maintenance calories, and targets for each goal.
- Metric or imperial. Switch between kg/cm and lb/ft-in with a tap.
- Instant & private. Worked out in your browser — nothing you enter is sent to us.
Maintain your weight
— kcal / day
Basal metabolic rate (BMR): — kcal
Mild weight loss
— kcal
Weight loss
— kcal
Mild weight gain
— kcal
Weight gain
— kcal
Worked out in your browser — nothing you enter is sent to us.
The science
How your daily calories are worked out
Two steps: estimate the energy your body burns at rest, then scale it up for how active you are.
Your BMR
Basal Metabolic Rate is the energy you'd burn doing nothing all day. We use the widely-trusted Harris–Benedict equation, which factors in your sex, weight, height and age.
Your activity
Multiply BMR by an activity factor — from 1.2 (sedentary) up to 1.9 (very hard exercise or a physical job) — to get your maintenance calories, or TDEE.
Your goal
To lose weight, eat below maintenance; to gain, eat above. Roughly 500 kcal a day maps to about half a kilo (one pound) a week.
A worked example
Take a 30-year-old man, 180 cm and 75 kg, who is moderately active. His BMR is about 1,787 kcal, and at an activity factor of 1.55 he burns roughly 2,769 kcal a day — his maintenance calories. To lose about half a kilo a week he'd eat near 2,269 kcal; to gain, about 3,269 kcal. Change the calculator above to see your own numbers.
The Calorie Calculator is one of DriveBird's free tools. If you like planning by the numbers, our EMI calculator does the same for a loan, and a fresh daily quote is never a bad way to start a healthy habit.
This calculator gives a general estimate and isn't medical or dietary advice. For a plan tailored to you, talk to a doctor or a registered dietitian.
Calorie calculator — frequently asked questions
How many calories should I eat a day?
It depends on your sex, age, size and activity. Enter them above to get your maintenance calories — the amount that keeps your weight steady — then eat below it to lose weight or above it to gain. As a rough guide, many adults sit somewhere between 1,600 and 3,000 kcal a day.
What is BMR and TDEE?
BMR (Basal Metabolic Rate) is the energy your body uses at complete rest. TDEE (Total Daily Energy Expenditure) is your BMR multiplied by an activity factor — it's the number of calories you actually burn in a typical day, which we label "maintain your weight".
How accurate is this calorie calculator?
It uses the well-established Harris–Benedict equation, which is a solid estimate for most people — but everyone's metabolism differs. Treat the result as a starting point, track your weight over a couple of weeks, and adjust up or down as needed.
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