What is a calorie deficit?
Eating fewer calories than you burn forces the body to use stored fat for energy, causing weight loss.
Health calculators
Calorie Deficit Calculator
Calculate how many calories to eat daily to reach your goal weight.
Complete guide
How to use Calorie Deficit Calculator
Enter your current weight, goal weight, weekly loss rate, and daily calories burned (TDEE). The calculator shows your daily calorie target, total deficit needed, and estimated date to reach your goal.
1 kg of fat = approximately 7,700 calories. Losing 0.5 kg/week requires a 3,850 calorie weekly deficit — about 550 calories per day.
Safe deficit range
500–750 kcal/day deficit is generally considered safe and sustainable. Above 1,000 kcal/day risks muscle loss.
TDEE (calories burned)
Total Daily Energy Expenditure — the total calories your body burns per day including activity. Use the TDEE Calculator to find yours.
Answers
Calorie Deficit Calculator FAQs
What is a calorie deficit?
A calorie deficit occurs when you eat fewer calories than your body burns. The gap forces your body to burn stored fat.
How many calories is a calorie deficit?
A 500 calorie/day deficit typically produces about 0.5 kg (1 lb) of fat loss per week.
Is 1000 calorie deficit safe?
A 1,000 calorie deficit can lead to muscle loss and nutritional deficiencies. 500–750 kcal/day is generally safer.
How do I find my TDEE?
Use the TDEE Calculator on FormatNest — it estimates daily calorie burn from your age, weight, height, and activity level.
How many calories should I eat to lose 1 kg per week?
1 kg per week requires a 7,700 calorie weekly deficit — approximately 1,100 calories less per day than your TDEE.
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