Health & FitnessReviewed Methodology
Calorie Deficit Calculator
A calorie deficit calculator estimates daily calorie targets by combining BMR and activity assumptions, then applying a chosen deficit percentage.
Health & FitnessReviewed by Editorial Health Review
Quick answer
Uses Mifflin-St Jeor BMR estimate.
Estimate only. This tool does not provide personal medical advice.
What this tells you
- •Uses Mifflin-St Jeor BMR estimate.
- •Applies activity factor to estimate TDEE.
- •Calculates target calories using chosen deficit percentage.
How to Use
- 1Select sex and enter age, weight, and height.
- 2Choose an activity factor.
- 3Set your deficit percentage and calculate.
- 4Use the result as an estimate, not medical advice.
How It Works
Formula
BMR (male) = 10W + 6.25H - 5A + 5
BMR (female) = 10W + 6.25H - 5A - 161
TDEE = BMR x activity factor
Target = TDEE x (1 - deficit%)BMR is estimated from body metrics and multiplied by activity level to derive TDEE before deficit is applied.
Calculation note: values are processed in the order shown above, using the current input units.
Worked Examples
Moderate activity example
SexMale
Age30
Weight80 kg
Height180 cm
Activity1.55
Deficit20%
ResultEstimated daily target calories and deficit amount
Common mistakes
- Treating formula output as medical diagnosis
- Choosing aggressive deficit without supervision
- Ignoring adherence and recovery signals
Limitations
This calculator is estimate-only and does not account for medical history, medications, body composition details, endocrine conditions, or adaptive metabolic changes.
Frequently Asked Questions
No. It is an estimate tool and not personal medical advice.
Real-world energy expenditure varies by physiology, activity tracking error, and metabolic adaptation.