TDEE Calculator
Estimate resting energy expenditure and TDEE using the Mifflin–St Jeor equation and an activity factor.
Open toolCalorie Deficit Calculator
Estimate adult maintenance calories and subtract your entered calorie deficit using body measurements and activity assumptions. This educational model is not a dietary prescription.
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How Calorie Deficit Calculator works
An activity-scaled adult energy estimate is reduced by the entered deficit.
The Mifflin–St Jeor form combines weight, height, age, and the chosen coefficient to estimate resting energy. The activity factor scales that estimate; the entered deficit is then subtracted from the estimated maintenance amount.
An educational adult estimate, not a weight-loss prescription. Activity multipliers and individual energy needs vary. The page does not calculate targets below 1,000 kcal/day. Not intended for pregnancy, children, or clinical nutrition decisions.
Reference: NIH/NIDDK Body Weight Planner.
How to use Calorie Deficit Calculator
The inputs define an educational adult energy estimate and a separately entered deficit.
Configure the adult model inputs
Enter weight in kilograms, height in centimetres, and adult age. Choose an equation coefficient and activity estimate, then enter the deficit to model. These are assumptions supplied to an educational calculation, not an individually recommended activity factor or deficit.
Weight
Calculate the entered-deficit estimate
Select Calculate and read the estimated intake target. The page estimates resting energy, scales it by activity, and subtracts the entered deficit. It does not choose a deficit or predict weight change for an individual.
1,641 kcal/day
Read both stages and the scope
Review Estimated maintenance, Resting estimate, and Entered deficit together. The page rejects outputs below 1,000 kcal/day; that software guard is not a personal safety threshold. The model is not intended for pregnancy, children, or clinical nutrition decisions.
Estimated maintenance
Compare resting energy, activity, and calorie deficit inputs
Use these comparisons to understand assumptions, without using the output as a weight loss prescription.
Understand the two calculation stages
Review the resting estimate and maintenance estimate to see the effect of the selected activity factor. Then identify the entered deficit as a separate subtraction. This keeps the population equation and the user's chosen deficit from being mistaken for the same assumption.
Compare activity assumptions
Hold the measurements, age, coefficient and deficit fixed while changing only the activity factor. The difference describes that modelling choice. It does not show which activity category accurately measures a particular person's day or establish an intake recommendation.
Investigate a result difference
If another educational calculator gives a different estimate, compare the entered units, equation coefficient, activity multiplier and deficit. Differences in those assumptions can explain the arithmetic. Neither matching numbers nor a permitted output establishes suitability for an individual.
Maintenance calories and the entered deficit
Keep resting, maintenance, and deficit stages separate when reading the result.
Estimated maintenance comes from the resting equation and selected activity factor. The main result subtracts the entered deficit and rounds for display. Each component remains an estimate; the page does not predict weight change or a timeline.
This is for educational adult use and is not intended for children, pregnancy or clinical nutrition decisions. Individual energy needs and activity vary. A professional assessment can consider circumstances absent from these fields.
Why the calculator rejects results below 1,000 kcal/day
Review adult scope and input assumptions without treating a guard as a recommendation.
The page refuses to calculate a result below one thousand kilocalories per day. That software limit does not mean a displayed value above it is suitable or safe for a particular person. Do not treat validation as clinical approval.
Check kilograms, centimetres and the selected coefficient when an estimate looks unexpected. Seek individual guidance for nutrition decisions instead of adjusting entries merely to make the form accept a lower number. This tool does not prescribe a plan.
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Open toolUse Calorie Deficit Calculator
Explore an educational adult energy estimate from body measurements, an activity factor, and an entered deficit.
Calorie Deficit Calculator: common questions
Answers about using Calorie Deficit Calculator and understanding its results.
Is this a precise calorie prescription?
No. It combines a population equation with a rough activity multiplier. A clinician or dietitian can assess personal needs.
What does the coefficient mean?
The original Mifflin–St Jeor equation uses different coefficients in its female and male forms. Choose the one appropriate for the estimate you want.
What happens below the page’s lower output limit?
The page does not calculate a target below 1,000 kcal/day. That software guard is not a statement that a value above it is suitable for a particular person.
Does this predict a weight change?
No. It shows an energy calculation under the entered assumptions. It does not predict an individual weight change or a safe dietary plan.