Calorie Deficit Calculator

Calculate your personalized calorie deficit for effective weight loss. This free calculator uses the scientifically-validated Mifflin-St Jeor equation to determine your BMR (Basal Metabolic Rate), TDEE (Total Daily Energy Expenditure), and optimal calorie target.

Understanding Your Results

Your calorie deficit is the difference between your TDEE (the calories you burn) and your daily calorie target. This creates the energy imbalance needed for weight loss.

BMR (Basal Metabolic Rate)

Your BMR is the number of calories your body burns at complete rest to maintain vital functions like breathing, circulation, and cell production. This calculator uses the Mifflin-St Jeor equation, which is more accurate than older formulas.

TDEE (Total Daily Energy Expenditure)

Your TDEE represents your total calorie burn including all physical activity. It's calculated by multiplying your BMR by an activity factor. Learn more about how TDEE works.

Daily Calorie Target

This is how many calories you should eat daily to achieve your weight loss goal. The calculator ensures you don't go below safe minimums: 1,200 calories for women and 1,500 for men, as recommended by health authorities.

Important: Very aggressive deficits (1000+ calories) should only be pursued under medical supervision. According to the NIH, sustainable weight loss is typically 0.5-1 kg (1-2 lbs) per week.

How to Use Your Calorie Deficit

Now that you know your target calories, follow these steps:

  1. Track your food intake: Use a food diary or app to log everything you eat
  2. Hit your protein target: Aim for the protein grams shown above to preserve muscle
  3. Choose filling foods: Focus on high-volume, low-calorie foods
  4. Stay consistent: Follow your calorie target 6-7 days per week
  5. Adjust as needed: Recalculate every 10-15 lbs of weight loss

Next Steps

Create a Meal Plan

Get sample meal plans that fit your calorie target.

View Meal Plans

Learn the Basics

Understand how calorie deficits work for weight loss.

Read Guide

Best Foods to Eat

Discover foods that keep you full on fewer calories.

Food List

Frequently Asked Questions

How accurate is this calorie deficit calculator?

This calculator uses the Mifflin-St Jeor equation, which is considered the gold standard for BMR estimation with an accuracy of ±10%. Individual variations exist due to factors like muscle mass, genetics, and metabolic health.

Should I eat the same calories every day?

Yes, consistency is key. However, having 1-2 days per week at maintenance calories can help with adherence and may benefit hormone levels during long-term dieting.

What if I'm not losing weight with my calculated deficit?

Weight loss isn't always linear. If you're not seeing results after 2-3 weeks, double-check your food tracking accuracy, consider hidden calories in cooking oils and condiments, and ensure you're tracking everything including drinks and snacks.

For more questions, visit our complete FAQ.