TDEE Calculator: How Many Calories Should You Actually Eat?
I spent about three years half-heartedly tracking calories and wondering why nothing was changing. The problem was not willpower. It was that I was using a completely wrong starting number. I was eating at what I thought was a deficit, but I had no idea what my actual maintenance calories were. TDEE fixed that.
TDEE stands for Total Daily Energy Expenditure. It is the total number of calories your body burns in a full day, including your base metabolic rate, physical activity, and the energy cost of digesting food. It is the only number you actually need to know before deciding how much to eat.
Find your Total Daily Energy Expenditure and get personalized calorie and macro targets based on your goal.
How the Calculator Works
The calculator uses the Mifflin-St Jeor equation to estimate your Basal Metabolic Rate (BMR), which is how many calories your body burns at complete rest. BMR is then multiplied by an activity factor to get your TDEE. This is the most widely validated formula for estimating calorie needs in healthy adults. It is what most registered dietitians use as a starting point.
The key word is starting point. No formula can perfectly account for individual variation in metabolism, muscle mass, hormones, or sleep quality. Use the TDEE number as your baseline and track actual results for 2-3 weeks before adjusting.
What BMR vs TDEE Actually Means
BMR is the calories you burn lying perfectly still doing nothing. You will never actually be at BMR unless you are sedentary in a hospital bed. TDEE accounts for everything you do in a day, including walking to your car, fidgeting, digesting food, and any exercise. TDEE is always the number you want for food planning.
Why Activity Level Is the Variable Most People Get Wrong
Most people overestimate their activity level. If you work a desk job and go to the gym three times a week, you are probably in the “light” to “moderate” category, not “active.” Choosing “active” when you are moderate will add several hundred calories to your estimate and explain why you are not losing weight despite “eating at a deficit.”
When in doubt, pick the lower activity level. You can always eat a little more if you are losing weight faster than intended. The opposite is much harder to fix once you have already built the habit of eating at the wrong number.
Understanding Your Macro Targets
Macros are the three main nutrient categories: protein, carbohydrates, and fat. Each one has a calorie cost per gram: protein is 4 cal/g, carbs are 4 cal/g, fat is 9 cal/g. The calculator sets starting macro targets based on your goal. Here is what to actually prioritize:
- Protein is the most important macro to hit. It preserves muscle during a cut, supports recovery when building, and is the most satiating macro. If you only track one thing, track protein.
- Carbs and fat are flexible. Some people do better with more carbs and less fat. Some do the opposite. Neither is inherently better for most people. Total calories and protein matter more than the carb-to-fat split.
- Fiber is not tracked in the calculator but aim for 25-35g daily. It matters for satiety and gut health in ways that show up quickly when you ignore it.
Frequently Asked Questions
How accurate is the TDEE calculator?
The Mifflin-St Jeor formula is accurate within about 10% for most healthy adults. That means a calculated TDEE of 2,400 could be anywhere from 2,160 to 2,640 in reality. Treat it as a starting estimate and adjust based on 2-3 weeks of real results. If you are eating 300 below TDEE and not losing weight, your actual TDEE is lower than the estimate.
How much of a calorie deficit should I eat at?
300-500 calories below TDEE is the standard recommendation for steady fat loss without significant muscle loss. Larger deficits can work faster short-term but tend to reduce muscle retention and make the deficit harder to maintain. Aggressive restriction also tends to backfire hormonally after several weeks.
Should I eat back exercise calories?
If you used the appropriate activity multiplier in the calculator. Those calories are already included in your TDEE. If you used “sedentary” but exercise regularly, then your TDEE is understated and you should eat some of those calories back. This is one of the most common sources of confusion in calorie tracking.
Does TDEE change as I lose weight?
Yes. As your body weight decreases, your BMR decreases because you have less mass to maintain. Recalculate every 5-10 kg of weight change. This is why progress plateaus. The calorie target that worked at 90 kg will not work at 80 kg if you do not adjust.
What is the difference between TDEE and BMR?
BMR is calories burned at complete rest with no activity. TDEE is your total daily burn including all movement and digestion. For almost everyone, TDEE is 20% to 90% higher than BMR depending on activity level. BMR alone is not useful for planning food intake.
The Short Version: Calculate your TDEE, not just your BMR. Eat at TDEE to maintain, 300-500 below to lose fat, 200-300 above to build muscle. Hit your protein target first. Reassess after 2-3 weeks of actual results and adjust from there.