Calorie Deficit Calculator
Estimate a daily calorie target for gradual fat loss by subtracting a chosen deficit from your maintenance energy needs.
Calculate Calorie Deficit
Medical Disclaimer: This is for informational purposes only—not medical advice. Consult a healthcare professional.
How this is calculated
Formula: Mifflin-St Jeor TDEE minus selected daily calorie deficit
We first estimate BMR from sex, age, height, and weight with Mifflin-St Jeor, then multiply it by your activity factor to calculate maintenance calories.
Your selected deficit is subtracted from maintenance. A 250-calorie daily deficit corresponds to roughly 0.5 lb per week and 500 calories to roughly 1 lb, although real loss is not perfectly linear.
The result includes a safety caution when it approaches commonly cited lower intake levels. Do not routinely go below about 1,200 calories per day for women or 1,500 for men without professional guidance.
Common calorie deficit ranges
| Daily deficit | Approximate weekly pace | Best suited to |
|---|---|---|
| 250 kcal | ~0.5 lb / 0.2 kg | A gentle, easier-to-sustain approach |
| 500 kcal | ~1 lb / 0.45 kg | A common moderate starting point |
| 750+ kcal | Faster on paper | Higher hunger and recovery risk; seek guidance |
Build a deficit you can sustain
Consistency matters more than the largest possible deficit. Preserve room for protein, fiber, essential fats, training fuel, and foods you enjoy.
Tips
- •Aim for a pace near 0.5–1% of body weight per week at most.
- •Keep protein high and resistance train to help preserve lean mass.
- •Judge progress using three to four weeks of average weights.
- •Reduce the deficit if sleep, mood, menstrual function, or training performance deteriorates.
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Frequently asked questions
Many adults begin with 10–20% below maintenance or about 250–500 calories per day. The appropriate amount depends on body size, health, activity, and adherence.
This estimate is for education and is not medical advice. Do not go below about 1,200 calories daily for women or 1,500 for men without guidance from a doctor or registered dietitian. Seek professional care if pregnant, breastfeeding, under 18, managing illness, or living with an eating disorder.
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