What is a calorie deficit?

A calorie deficit means consuming fewer calories than your body burns each day. Over time, this causes your body to use stored energy (primarily body fat), which leads to weight loss.

What is a safe calorie deficit for weight loss?

A deficit of 10–25% below your TDEE is generally considered safe and sustainable. This typically results in 0.25–0.75 kg of weight loss per week. Larger deficits may cause muscle loss and nutrient deficiencies.

How many calories are in a kilogram of fat?

Approximately 7,700 kcal equates to 1 kg of body fat. A daily deficit of 550 kcal would theoretically result in approximately 0.5 kg of fat loss per week, though real-world results vary due to water retention and metabolic adaptation.

Should I exercise as well as eating in a deficit?

Yes. Combining a moderate calorie deficit with regular exercise helps preserve muscle mass, improves fitness and supports sustainable weight loss. Exercise can also increase your TDEE, giving you more flexibility in your calorie budget.

Free Calorie Deficit Calculator

A calorie deficit means consuming fewer calories than your body burns each day. This calculator helps you set a sustainable deficit based on your TDEE so you can lose weight steadily without extreme restriction.

Calculate Your Calorie Deficit

Enter your details and choose a deficit level to get your daily calorie target.

Choosing the Right Deficit

10% (Mild)

Very gradual. Best for those close to their goal weight or concerned about muscle loss.

Est. rate: ~0.1–0.2 kg/week

15% (Moderate)

Steady, comfortable pace. Good balance of sustainability and results.

Est. rate: ~0.2–0.3 kg/week

20% (Standard)

The most commonly recommended range for healthy weight loss. Still allows adequate nutrition.

Est. rate: ~0.3–0.5 kg/week

25% (Higher)

Faster progress but requires discipline and careful attention to protein intake to protect muscle mass.

Est. rate: ~0.4–0.7 kg/week

These are general estimates. Real weight change depends on many factors including water retention, hormones, and metabolic adaptation.

How the Calculation Works

1. Calculate your TDEE (BMR × activity multiplier)

2. Apply your chosen deficit percentage: Daily Target = TDEE × (1 − deficit%)

3. Your weekly deficit = Daily Deficit × 7

Example: TDEE of 2,500 kcal with 20% deficit → Daily Target = 2,500 × 0.80 = 2,000 kcal/day

TDEE Calculator

Calculate your total daily calorie needs based on activity level.

Macro Calculator

Calculate your ideal protein, carbohydrate and fat targets.

Protein Calculator

Find your daily protein requirements based on your training and goals.

Turn Your Deficit Into a Complete Plan

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Frequently Asked Questions

Medical Disclaimer: Calorie targets are estimates. Always eat enough to meet your nutritional needs. Do not follow extreme deficits without medical supervision. Full disclaimer →