Free Calorie & TDEE Calculator — Daily Calories + Macro Split with AI

What Is TDEE — and Why It Matters More Than Calorie Counting

TDEE (Total Daily Energy Expenditure) is the number of calories your body burns in a full day — adding up everything from the basic work of staying alive (BMR) to the energy used walking, typing, chewing, and training. If you eat exactly your TDEE, your weight stays flat. Eat less, you lose. Eat more, you gain. Every weight- change goal ultimately sits on top of this one number.

Most fitness apps skip straight to “eat X calories” without teaching where the number comes from. The result is that users hit a plateau, assume the calculator was wrong, and add a new mystery variable. This calculator shows you each layer: BMR, TDEE maintenance, goal-adjusted target, and the macro split — so when something needs tweaking you know exactly which dial to turn.

The Mifflin-St Jeor Formula

Mifflin-St Jeor has been the gold standard since the mid-2000s, outperforming Harris- Benedict in every head-to-head validation study. It has about ±10% individual-level error, which means your calculated TDEE could sit 200–300 calories off from your true maintenance. The fix is not a different formula — it’s a 2-week check-in: eat at the calculated target, weigh weekly, and adjust ±100 kcal/day if the trendline isn’t moving the way you want.

From BMR to TDEE — Activity Multipliers

BMR is what you burn at complete rest. Real life adds movement. Activity multipliers scale BMR up to daily reality:

• 1.2 — Sedentary. Desk job, no structured exercise, most steps incidental. This is more common than users estimate.
• 1.375 — Light. 1–3 structured workouts per week, or a job with meaningful walking.
• 1.55 — Moderate. 3–5 workouts per week. The right default for most gym-going office workers.
• 1.725 — Very active. 6–7 structured workouts per week, or physical work plus some training.
• 1.9 — Extra active. A physical job plus serious training. Construction + powerlifting; farmwork + endurance running; etc.

Honesty tax.Overestimating activity is the single most common reason a “deficit” plan produces zero weight loss. If in doubt, drop one tier — the weight data will tell you within 2 weeks whether to move back up.

Goals & Their Calorie Deltas

• Maintain: eat your TDEE. Protein stays anchored at 1.8 g/kg — protecting lean mass matters at every goal.
• Lose (gentle −250): about 0.5 lb (0.25 kg) per week. Slowest but the easiest to stick with indefinitely.
• Lose (standard −500): about 1 lb (0.45 kg) per week. The widely- endorsed ceiling for sustainable fat loss.
• Lose (aggressive −750): 1.5 lb per week. Only sustainable for short periods (4–8 weeks), and only with strict resistance-training adherence to minimize muscle loss.
• Gain (+300): about 0.5 lb per week — a lean bulk. Protein bumps to 2.0 g/kg to fuel muscle-protein synthesis.
• Gain (aggressive +500): 1 lb per week. Faster strength and size gains, more fat comes along for the ride.

Why Protein Is Anchored to Bodyweight (Not Calories)

Most “30/40/30” macro splits distribute protein as a percentage of calories, which is backwards — what your body needs is a fixed amount per kilogram of lean mass, regardless of how many calories you happen to be eating that day. This matters most in a deficit: if protein scales down with calories, you’re guaranteed to lose muscle along with fat.

Our default of 1.8 g/kg(bumped to 2.0 g/kg for gaining phases) reflects current meta-analyses on muscle-protein synthesis. For a 75-kg adult that’s about 135 g/day — a scoop of whey, two palm-sized meat portions, a Greek-yogurt breakfast, and you’re there. Fat lands at a flat 25% of total calories (essential for hormone production and fat-soluble vitamin absorption). Carbs fill whatever remains — they aren’t “bad,” they’re the flexible variable.

How to Use This Calculator

1. Pick your unit system, biological sex, and fill in age, weight, height.
2. Choose the activity level that honestly describes a typical week — not your best week.
3. Pick a goal. For first-time users: “Lose (standard −500)” or “Maintain” are the safe starting points.
4. Read the BMR, TDEE, and target calories. The macro split is a starting point, not a rigid rule — the weekly protein total is what matters more than the daily target.
5. Eat the plan for 2 weeks, weigh daily, then adjust ±100 kcal/day based on trend, not day-to-day noise.

Three Worked Examples

Three specific people, three different goals — copy any of them into the calculator above to see the full breakdown. The numbers below round to the same values the tool produces.

Example 1 — 30-year-old male, maintaining

80 kg, 175 cm, moderate activity (3–5 workouts per week, multiplier 1.55), goal: maintain. BMR works out to ≈ 1,730 kcal (10 × 80 + 6.25 × 175 − 5 × 30 + 5). TDEE = 1,730 × 1.55 ≈ 2,682 kcal, and because the goal is maintenance, the daily target stays at 2,682 kcal. Macros: protein at 1.8 g/kg = 144 g (576 kcal), fat at 25% of calories ≈ 75 g (671 kcal), carbs fill the remainder at roughly 360 g (1,435 kcal). Notice how carbs become the flex variable — they absorb whatever calories protein and fat don’t claim.

Example 2 — 28-year-old female, steady fat loss

65 kg, 165 cm, light activity (1–3 workouts per week, multiplier 1.375), goal: lose 0.5 kg per week (−500 kcal). BMR ≈ 1,387 kcal (10 × 65 + 6.25 × 165 − 5 × 28 − 161). TDEE ≈ 1,907 kcal, target = 1,907 − 500 ≈ 1,407 kcal. Protein stays anchored to bodyweight at 1.8 g/kg = 117 g(468 kcal, ~33% of total) — in a deficit this is the single most important macro to lock in. Fat lands at ≈ 39 g (351 kcal); carbs fill ≈ 140 g (560 kcal). This is a lean, protein-forward plate, which is exactly what a fat-loss phase should look like.

Example 3 — 22-year-old male, lean bulk

70 kg, 178 cm, very active (6–7 workouts per week, multiplier 1.725), goal: gain 0.25 kg per week (+250 kcal surplus — we’ll use +250 here for a clean bulk; the calculator offers +300 and +500 presets). BMR ≈ 1,697 kcal, TDEE ≈ 2,927 kcal, target ≈ 3,177 kcal. Protein bumps to 2.0 g/kg = 140 g (560 kcal), fat ≈ 88 g (794 kcal), carbs fill the rest at ≈ 410 g (1,640 kcal). That’s a carb-heavy plate by design — high-volume training at this bodyweight demands glycogen replacement, and carbs are the cheapest fuel for that job.

When This Calculator Decides For You

TDEE math is rarely academic — the output usually maps to a real decision you’re about to make. The four most common:

1. Starting a cut or bulk. Day one is where most plans fail: users eyeball a number from a fitness magazine and end up either too aggressive (crashing in week three) or too timid (no visible progress in month two). Running your own numbers through Mifflin-St Jeor with honest activity gives you a defensible starting target — and a paper trail to adjust from when the scale data comes in.
2. Breaking through a plateau.Weight-loss math is not static: as you drop kilos, your BMR drops with them. A plateau at week 8 often just means your new bodyweight has a lower TDEE than your starting weight did. Re-run the calculator with today’s bodyweight — the target usually needs to come down 80–150 kcal to re-establish the deficit.
3. Changing training volume.Adding a fourth weekly session or picking up a sport shifts your activity multiplier up a tier. That can easily be a 300–400 kcal jump in TDEE. Recalculating prevents the “I’m training more but losing weight anyway” accidental deficit that eats into recovery and strength.
4. Transitioning to maintenance after a phase. Ending a cut or bulk cleanly means raising (or lowering) calories back to maintenance, not to whatever the last app told you. Recalculate from your current stats, then sit at that number for 4–6 weeks before the next phase. This reverse-diet discipline is what separates people who keep their results from people who bounce.

Why Mifflin-St Jeor Wins (And When It Doesn’t)

Mifflin-St Jeor was published in 1990, and the Frankenfield et al. 2005 meta-analysis(Journal of the American Dietetic Association) is what cemented it as the default for the general adult population. Frankenfield’s team compared every major BMR equation — Harris-Benedict, Owen, WHO/FAO, Mifflin — against indirect calorimetry measurements on 2,528 subjects. Mifflin hit within 10% of measured BMR for 82% of non-obese adults and 70% of obese adults, beating every competitor including the older and more widely-taught Harris-Benedict. That gap is why clinical dietitians, sports scientists, and modern fitness software all default to Mifflin.

The catch is that any single-equation approach gets shakier at the extremes. Very lean athletes (sub-10% body fat men, sub-18% women) have more lean mass per kilogram of bodyweight than the Mifflin sample, so the equation under-predicts their BMR — a 85 kg bodybuilder and a 85 kg sedentary office worker get the same Mifflin number despite hugely different metabolic rates. At the other end, very heavy or very sarcopenic older adults carry different lean-mass ratios too. The gold-standard fix is a DEXA scan to measure fat-free mass (FFM) directly, then plug it into the Katch-McArdle equation(BMR = 370 + 21.6 × FFM in kg), which is FFM-based and doesn’t care about your overall weight. DEXA access requires a lab and costs money in most regions, which is why FFM-based equations remain a specialist tool rather than the default.

This is also why we anchor protein to 1.8–2.0 g/kg bodyweightinstead of to a percentage of calories. Protein’s job — maintaining lean mass and driving muscle-protein synthesis — is tied to your tissue, not to how many carbs you happen to be eating that day. A 70 kg lifter needs roughly 126 g of protein whether they’re in a 2,000-kcal cut or a 3,200-kcal bulk. Scaling protein down with calories in a deficit is one of the most reliable ways to lose muscle along with fat — exactly the outcome a good plan is supposed to prevent.

Common Mistakes

• Treating the number as exact.It’s ±10% at the individual level. Measure, adjust, repeat — that’s the feedback loop.
• Ignoring muscle during a deficit. Without resistance training, 25–40% of the weight you lose comes from muscle. Lifting 3× per week flips that ratio dramatically in your favor.
• Underestimating liquid calories.Juices, alcohol, flavored coffee, smoothies routinely add 400–800 kcal per day without showing up in memory. Track honestly for a week and you’ll often find the problem right there.
• Raising activity multiplier to justify more food.If the weight data isn’t moving, the multiplier is wrong — drop it one tier before adding variables.
• Not recalculating after a significant weight change. Lose 8 kg and your BMR has dropped by roughly 80 kcal. Keep eating your old target and the deficit quietly disappears. Re-run the numbers every 5–8 kg of body-composition change.
• Skimping on sleep, then blaming the calories. Sleep debt raises ghrelin (hunger hormone) and lowers leptin (satiety) — making adherence feel impossible at any calorie target. Fix the upstream variable before touching the downstream one. Our sleep-cycle calculatoris a good starting point if you’re running on 6 hours and wondering why the plan isn’t sticking.

Pair It With

TDEE is the calories-in side. The BMI calculator is the weight-range side — it tells you whether your current weight sits inside the WHO healthy band for your height. Used together you get a full picture: where you are, where the healthy band starts, and what daily calorie target gets you there on a realistic timeline. Two Phase-2 tools round out the plan: the water-intake calculator pairs hydration to bodyweight and activity (under-drinking blunts training output and fogs hunger cues), and the protein-intake calculatorlets you fine-tune the 1.8–2.0 g/kg default for your specific goal, training age, and lean-mass status — especially useful when you’re near the extremes Mifflin-St Jeor handles least well. And if sleep keeps undermining your adherence, the sleep calculator is the fastest upstream fix.