Calorie Deficit Calculator
Calculate the daily calorie intake needed to reach your target weight loss goals.
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Result
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Formula
Finds your maintenance calories (TDEE) and subtracts the amount needed to lose fat (roughly 3,500 calories per pound).
Worked Example
How Calorie Deficits Drive Weight Loss
- Formula: Daily Target = TDEE - (Weekly Loss in lbs x 500). A 1 lb/week goal requires a 500 calorie daily deficit
- One pound of body fat stores approximately 3,500 calories of energy
- Safe weight loss rate: 0.5 to 2.0 lbs per week for most adults
- Minimum recommended intake: 1,200 calories/day for women, 1,500 for men, unless medically supervised
- Aggressive deficits above 1,000 calories/day risk muscle loss, nutrient deficiencies, and metabolic adaptation
Sustainable weight loss combines a moderate calorie deficit with adequate protein intake and regular physical activity. Consult a healthcare provider before starting any diet plan.
You can also calculate changes using our Ideal Weight Calculator or Waist-to-Height Ratio Calculator.
Frequently Asked Questions
Is a 500 calorie deficit good?
Yes. A 500-calorie daily deficit produces approximately 1 lb of fat loss per week (500 x 7 = 3,500 calories). This rate is widely considered safe and sustainable for most adults.
What is the minimum calories I should eat?
General guidelines suggest women should not go below 1,200 calories and men should not go below 1,500 calories per day without medical supervision. Going too low risks nutrient deficiencies and metabolic slowdown.
Does a calorie deficit guarantee weight loss?
Calories are the primary driver, but factors like water retention, hormonal changes, sleep quality, stress, and medication can temporarily mask fat loss on the scale. Consistency over weeks is what matters.
How many calories are in one pound of fat?
One pound of body fat stores approximately 3,500 calories. This means a cumulative deficit of 3,500 calories, spread over any timeframe, will result in roughly one pound of fat loss.
Will a large deficit help me lose weight faster?
Very large deficits (over 1,000 calories/day) can cause muscle loss, fatigue, nutrient deficiencies, and metabolic adaptation where your body slows its calorie burn. A moderate deficit of 500 to 750 calories/day is more effective long term.
Should I eat back exercise calories?
Partially. If your deficit is already moderate (500 cal/day), eating back 50% to 75% of exercise calories helps prevent excessive hunger and muscle loss while still maintaining progress.
Medical Disclaimer
This calculator is provided for informational and educational purposes only. It is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making any decisions based on these results. Do not disregard or delay seeking medical advice because of information obtained from this tool.
AI Assistant
Ask about this calculator
I can help you understand the calorie deficit calculator formula, interpret your results, and answer follow-up questions.
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Our AI assistant provides general estimates and advice only. Please consult a qualified healthcare professional before making any health-related decisions.
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