CalcVitalsTDEE Calculator — Total Daily Energy Expenditure
TDEE is BMR multiplied by an activity factor. A man with a BMR of 1,649 who is moderately active (×1.55) has a TDEE of 2,556 kcal a day — eat that much and, on average, his weight stays where it is.
How it works
TDEE answers the most practical question in nutrition: how much can I eat without my weight changing? It builds the answer in two parts — your basal metabolic rate, the cost of simply existing, multiplied by a factor that bundles in everything else: work, walking, training, fidgeting, even the energy cost of digesting food itself.
The five multipliers are conventions, not measurements, and the jump between levels is large — one level is worth roughly 250–330 kcal a day for an average adult, easily the difference between slow loss and slow gain. This is why the page prints all five figures rather than just yours: if the number you picked feels generous, look at the one below it before blaming the arithmetic.
Even a well-chosen TDEE is an estimate with a real error bar, commonly ±200 kcal. The professional way to use it is as a starting hypothesis: eat at the figure for two to three weeks, watch the trend of your average weight, and adjust by 100–200 kcal toward your goal. Your own data, once you have it, outranks any formula — including this one.
The method
TDEE = BMR (Mifflin-St Jeor) × activity factor: 1.2 sedentary, 1.375 light, 1.55 moderate, 1.725 very active, 1.9 athlete. Maintenance calories ≈ TDEE by construction.
Frequently asked questions
How do I know my real activity level?
Anchor it in steps and job type, not intentions. Under 5,000 steps with a desk job is sedentary (×1.2) even with three gym sessions a week; 8,000–10,000 steps plus regular training is genuinely moderate (×1.55).
Why is my weight changing when I eat at my TDEE?
Either the activity level is optimistic, the intake tracking is (the usual suspect — oils, drinks and weekends), or three weeks is too short a window and water weight is masking the trend. Adjust by small steps, 100–200 kcal, and re-judge monthly.
Does TDEE change as I lose weight?
Yes — a smaller body costs less to run and to carry, typically 20–30 kcal less per kilogram lost. Recalculate every 5 kg or so, or weight loss will quietly stall.