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Health and fitness formula

How to calculate calorie deficit

A calorie deficit estimate sets intake below maintenance to support weight loss.

See the formulaOpen calculator
Direct answer
Formula
daily intake = TDEE - daily deficit

Use the table below to match each symbol with the right input. Keep units consistent before you start.

Calorie deficit formula
Start here when you only need the equation and variable names.
Formula
daily intake = TDEE - daily deficit

A calorie deficit estimate sets intake below maintenance to support weight loss.

Variable meanings
Check each symbol, meaning, and unit before you calculate.
SymbolNameDescriptionUnit
TDEETotal daily energy expenditureEstimated calories burned per day.calories per day
daily deficitDaily deficitCalories below estimated maintenance.calories per day
When to use this formula
Check that your situation matches the formula before you trust the result.
  • Start with it for a calorie target, then adjust based on energy, hunger, training, and weight trend.
Step-by-step method
Follow these steps when you are solving it by hand.
  1. 1Estimate TDEE.
  2. 2Pick a weekly loss rate.
  3. 3Convert weekly pounds to a daily deficit with about 500 calories per pound per week.
  4. 4Subtract the deficit from TDEE.
Examples
These sample numbers show the order of operations and units.
One pound per week
TDEE
2,500
loss rate
1 lb/week
  1. 1.daily deficit = 1 * 500 = 500
  2. 2.daily intake = 2500 - 500
  3. 3.daily intake = 2000
Result
The target estimate is 2,000 calories per day.
Half pound per week
TDEE
2,100
loss rate
0.5 lb/week
  1. 1.daily deficit = 0.5 * 500 = 250
  2. 2.daily intake = 2100 - 250
  3. 3.daily intake = 1850
Result
The target estimate is 1,850 calories per day.
Mistakes to avoid
Small input or unit errors can change the answer a lot.
  • Treating the calorie deficit result as a diagnosis or a personal training plan.
  • Mixing inches, centimeters, pounds, and kilograms without converting first.
  • Using stale measurements after weight, activity, or training level changes.
  • Ignoring the method assumptions behind the estimate.
Open the Calorie Deficit Calculator
Open the calculator for the answer without rewriting the formula.

Enter your values in the related calculator, then compare the output with the hand method above.

Open Calorie Deficit Calculator
FAQs
Short answers for common formula questions.
Is the Calorie deficit formula a medical test?

No. It gives an estimate from a few inputs. Treat it as a planning or screening number, and ask a qualified clinician about symptoms, medication, pregnancy, eating disorders, or medical conditions.

Why can my Calorie deficit result differ from a wearable or lab test?

Different methods use different assumptions. Small measurement changes, activity estimates, and rounding can move the result.

Can I use the Calorie Deficit Calculator instead?

Yes. The Calorie Deficit Calculator handles the arithmetic and helps catch unit conversion mistakes.