TDEE Calculator
Calculate your daily calorie needs and macro breakdown in 30 seconds
Your Information
= 187 lbs
= 178 cm
Daily Calories
3157
calories/day
Basal Metabolic Rate (BMR)
1830
Activity Factor
1.725x (active)
Protein
253g (32%)
Fat
88g (25%)
Carbs
339g (43%)
Calorie Comparison
Protein (32%)
4 calories per gram. Essential for muscle repair and maintenance.
Fat (25%)
9 calories per gram. Important for hormone production and nutrient absorption.
Carbs (Remainder)
4 calories per gram. Primary energy source for your body.
Your Passive Calorie Burn Timeline
10:33 PM
0% of day
By the end of the day, your body will burn ~1830 kcal naturally.
6 AM
~250 kcal
12 PM
~500 kcal
6 PM
~1250 kcal
12 AM
~1830
What This Looks Like in Real Food
Big Mac
550 kcal per serving
≈ 6
burgers
Slice of pizza
285 kcal per serving
≈ 11
slices
Bowl of rice
200 kcal per serving
≈ 16
bowls
Chicken breast
165 kcal per serving
≈ 19
breasts
💡 Tip: These are approximate values. Actual calories vary based on preparation and brand.
Most of your daily burn comes from movement, not your resting metabolism. Your TDEE is highly sensitive to changes in activity — a rest day makes a real difference.
What changes if…
10 years from now
−87 kcal
estimated TDEE change with age alone
One more active
+320 kcal
moving up one activity tier
10 kg lighter
−173 kcal
estimated TDEE at 75 kg
A day of eating for your goal
Portions are calculated to hit your 3157 kcal target. Primary ingredients are capped at realistic serving sizes. Use ↻ to explore alternatives or ♥ to lock in a meal.
Daily Totals
Total Calories
0
kcal
Protein
0
grams
Carbs
0
grams
Fat
0
grams
Goal
0%
of target
How your numbers were calculated
Your BMR — 1,830 kcal — is the energy your body burns at complete rest. It was calculated using the Mifflin-St Jeor formula, which takes your weight, height, age, and sex as inputs. It represents what your body spends just to stay alive: breathing, circulation, cell repair, and temperature regulation.
That baseline was multiplied by your activity level to produce your TDEE of 3,157 kcal — what you actually burn across a full day. The largest variable here is movement: a sedentary day and an active day can differ by 600–800 kcal for the same person.
Your goal adjusts that number by 500 kcal in either direction. The ±500 figure targets roughly half a kilogram of change per week — the rate research consistently identifies as sustainable without significant muscle loss on the way down or excess fat gain on the way up.
Your macros are divided from that goal: 32% from protein, 25% from fat, and carbohydrates fill the remainder. Carbs are calculated last so rounding is absorbed there — your protein and fat gram targets are exact, and the three always sum precisely to your calorie goal.
What your body actually burns — and why most calorie advice gets it wrong
Somewhere between the fitness influencer telling you to eat 1200 calories and the bulk-phase bro insisting you need 4000, there's a number that's actually yours. It's not borrowed from a generic meal plan or reverse-engineered from someone else's transformation photo. It comes from your biology — specifically, from two numbers that most people have heard of but few actually understand: BMR and TDEE.
BMR: the cost of being alive
Your basal metabolic rate is the number of calories your body burns doing absolutely nothing. No walking, no working out, no fidgeting. Just existing — breathing, circulating blood, regulating temperature, repairing cells, running every quiet background process that keeps you alive while you sleep.
For most people, this number sits somewhere between 1400 and 2000 calories. It accounts for roughly 60–70% of everything you burn in a day. Which means the largest share of your daily energy expenditure has nothing to do with the gym.
BMR is shaped by four things: your weight, your height, your age, and your sex. Heavier bodies burn more at rest because there's simply more tissue to maintain. Taller people tend to have more surface area, which drives up energy expenditure. Age pulls it down — metabolism slows gradually from your late twenties onward, not dramatically, but consistently. And biological sex matters because of differences in muscle-to-fat ratios; muscle is metabolically expensive tissue, and men typically carry more of it.
The formula used here — Mifflin-St Jeor — was developed in 1990 and remains the most accurate general-population estimate available. 1 It consistently outperforms the older Harris-Benedict equation in clinical validation studies. 2 It's the one most registered dietitians use today.
TDEE: what you actually burn
Total daily energy expenditure is your real number — BMR scaled up by how active your life actually is. A sedentary office worker and a construction laborer with identical height, weight, age, and sex can have TDEEs that differ by 800 calories or more. Same body, completely different energy demands.
Activity multipliers are blunt instruments. They have to be — there's no formula that can account for the specific mix of your commute, your job, your training, and how much you move between all of it. What the five tiers give you is a reasonable starting range. Treat your calculated TDEE as a hypothesis, not a prescription. Track for two to three weeks, observe what actually happens to your weight, and adjust from there. The calculation gets you close; your own data gets you accurate.
The ±500 rule
The standard recommendation for weight change is a 500 calorie daily adjustment from TDEE — a deficit for loss, a surplus for gain. This maps to roughly half a kilogram per week in either direction, which sits in the range that research consistently identifies as sustainable: 4 fast enough to be motivating, slow enough to preserve muscle on the way down and minimize fat gain on the way up.
Faster deficits are possible but come with tradeoffs. Below about 1200 calories for women and 1500 for men, the body starts defending itself — hunger hormones rise, energy expenditure drops, and adherence collapses. The math stops working because the body stops cooperating.
The ±500 figure is a starting point. Some people do better with a smaller deficit and more patience. Some handle a larger surplus in a gaining phase. The number gives you a framework; your experience over weeks and months tells you how to adjust it.
Why macros matter more than calories alone
Once you have a calorie target, the next question is what those calories are made of. Protein, fat, and carbohydrates all provide energy, but they do different things once they're inside you.
Protein is structurally irreplaceable. During a deficit especially, adequate protein — around 1.6 to 2.2 grams per kilogram of bodyweight 5 — is what separates losing fat from losing fat and muscle. It also has the highest thermic effect of any macronutrient, 3 meaning your body burns more calories just processing it. The 32% protein allocation used here is a reasonable default for active people; it may be worth pushing higher if you're training hard in a deficit.
Fat is not optional. Hormones are synthesized from it. 6 Fat-soluble vitamins — A, D, E, K — require it for absorption. Dropping fat below roughly 20% of total calories tends to cause problems that show up slowly and confusingly: hormonal disruption, mood changes, joint issues. The 25% allocation here keeps you well above that floor.
Carbohydrates absorb the remainder. They're the body's preferred fuel for high-intensity work, and they're the most flexible macro — easier to increase or decrease without the downstream effects that come from moving protein or fat significantly. If you're sedentary, the carb allocation will be lower; if you're training daily, it'll be higher. The calculator handles this automatically as activity level changes.
What this calculator won't tell you
It won't tell you what to eat. It won't account for medical conditions that affect metabolism — hypothyroidism, PCOS, insulin resistance — all of which can make real-world results diverge from calculated predictions. It won't replace a conversation with a registered dietitian if your situation is complex.
What it will give you is a defensible, evidence-based starting point. A number derived from the best available formula, adjusted for your activity level, split into macros that reflect what sports nutrition research actually supports. From there, the work is observational — watching what happens, adjusting what isn't working, and building an understanding of your own body that no calculator can substitute for.
The number is the beginning of the experiment, not the answer to it.
Sources
- Mifflin MD, et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990. PubMed
- Frankenfield D, et al. Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults. J Am Diet Assoc. 2005. PubMed
- Westerterp KR. Diet induced thermogenesis. Nutr Metab. 2004. PubMed
- Garthe I, et al. Effect of two different weight-loss rates on body composition and strength and power-related performance in elite athletes. Int J Sport Nutr Exerc Metab. 2011. PubMed
- Morton RW, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 2018. PubMed
- Hämäläinen E, et al. Diet and serum sex hormones in healthy men. J Steroid Biochem. 1984. PubMed
