Calorie Calculator (TDEE): How Many Calories Do I Need?
Free calorie calculator to find your BMR and TDEE (maintenance calories), plus daily targets for weight loss and muscle gain. Works in lb/ft or kg/cm.
How this calorie calculator works
Your body burns energy all day long, even while you sleep. The total is called your total daily energy expenditure (TDEE). It is made of four parts:
- Basal metabolic rate (BMR): the energy needed to keep you alive at rest. It is usually 60–70% of total burn.
- Thermic effect of food: about 10% of calories are used to digest food. Protein has the highest effect.
- Non-exercise activity (NEAT): walking, standing, fidgeting, chores. It varies hugely between people.
- Exercise: your workouts.
We calculate BMR with the Mifflin-St Jeor equation, which studies have found to be among the most accurate for healthy adults, then multiply it by an activity factor.
Activity levels explained
| Level | Multiplier | Description |
|---|---|---|
| Sedentary | 1.2 | Desk job, little exercise, under ~5,000 steps per day |
| Lightly active | 1.375 | Light exercise 1–3 days per week |
| Moderately active | 1.55 | Moderate exercise 3–5 days per week |
| Very active | 1.725 | Hard exercise 6–7 days per week |
| Extremely active | 1.9 | Physical job plus hard training |
Most people overestimate their activity. If you are unsure, choose one level lower.
Calories for weight loss
One pound of body fat holds roughly 3,500 calories (about 7,700 per kilogram). A deficit of about 500 calories per day therefore leads to roughly 1 lb (0.45 kg) of weight loss per week in the early stages, although real-life loss slows over time as your body adapts. A safe, sustainable target for most people is 0.5–1% of body weight per week. Very low-calorie diets (under about 1,200 calories for women or 1,500 for men) should only be followed under medical supervision.
Calories for muscle gain
To build muscle you need a small surplus, typically 5–15% above maintenance, together with progressive strength training and enough protein. Bigger surpluses mostly add fat.
Adjust based on real results
Every calculator gives an estimate. Track your morning weight for 2–3 weeks. If your weekly average is not moving in the right direction, adjust by 100–200 calories per day and reassess.
How to use your result
A calculator gives you a starting point, not a final answer. The most reliable way to use any fitness number is the measure → act → review loop:
- Measure: record your result today, along with your morning body weight, waist measurement and a few photos.
- Act: follow a matching plan for 2–4 weeks. Use the plan builder to get a workout program and a 7-day meal plan that fit your numbers.
- Review: compare your weekly averages and measurements. If things are moving in the right direction at a sustainable pace, keep going. If not, adjust by small amounts (100–200 calories, one extra workout, 2,000 extra steps) and review again.
US and metric units
Every HelloMyTrainer calculator works in both systems. Use the lb / ft or kg / cm switch at the top of the page; your choice is remembered on this device for all calculators and meal plans. Useful conversions: 1 kg = 2.2 lb, 1 inch = 2.54 cm, 1 foot = 30.48 cm, 1 liter = 33.8 US fluid ounces.
Who should be careful with these numbers
These calculators are designed for healthy adults aged 18 and over. They are not suitable for children or teenagers, pregnant or breastfeeding women, people with a history of eating disorders, competitive athletes with very high muscle mass, or people with medical conditions that affect weight, metabolism or fluid balance (such as heart failure, kidney disease or thyroid disorders). If any of these apply to you, please speak with your doctor or a registered dietitian before using the results.
Your privacy
We never ask for your name, email or any personal details to use our tools. The calculations run in your web browser and the numbers you type are not sent to our servers. See our Privacy Policy for details.
Frequently asked questions
How many calories should a woman eat to lose weight?
Many women lose weight steadily on 1,400–1,800 calories per day, depending on size and activity. Use the calculator for your personal number.
How many calories should a man eat to lose weight?
Many men lose weight on 1,800–2,400 calories per day. Taller and more active men need more.
Should I eat back exercise calories?
The activity multiplier already includes your planned exercise, so you do not need to add calories for normal workouts.
More free fitness calculators
- BMI Calculator
- Macro Calculator
- Body Fat Calculator
- One Rep Max Calculator
- Water Intake Calculator
- Build My Plan
Results are estimates for healthy adults and are not medical advice.