How Many Calories Should I Eat to Lose Weight?
How to find your daily calorie target for weight loss using TDEE and a calorie deficit, with realistic rates of loss and why crash diets backfire.
Weight loss comes down to a calorie deficit — eating fewer calories than your body burns in a day (your TDEE). The size of that deficit determines how fast you lose weight, and how sustainable the process feels.
The math behind a calorie deficit
One pound of body fat stores roughly 3,500 calories. A daily deficit of 500 calories below your TDEE produces about 1 lb (0.5 kg) of loss per week; a 250-calorie deficit produces roughly half that. Larger deficits work faster but are harder to sustain and risk muscle loss along with fat.
Typical deficit targets
| Daily deficit | Approx. weekly loss |
|---|---|
| 250 kcal (mild) | ~0.25 kg / 0.5 lb |
| 500 kcal (standard) | ~0.5 kg / 1 lb |
| 1,000 kcal (aggressive) | ~1 kg / 2 lb |
Why crash diets backfire
Very large deficits (1,000+ calories) are hard to sustain, often trigger muscle loss alongside fat loss, and can slow your metabolism over time as your body adapts. A moderate, protein-forward deficit you can maintain for months usually beats an aggressive one you abandon after two weeks.
Start with your TDEE from the TDEE & BMR Calculator, apply a 250-500 calorie deficit, and track your weight trend over 2-3 weeks to see how your body actually responds before adjusting further.