Health

Calorie Deficit Calculator

Find your daily calorie target for weight loss by entering your TDEE and your desired weekly loss rate.

Don't know your TDEE? Use the TDEE Calculator first.

Enter your TDEE above to calculate your daily calorie target.

Advertisement

Calorie Deficit Formula

Daily Target

Target = TDEE − Deficit

Weekly Fat Loss

lbs/wk = (Deficit × 7) / 3500

What is a calorie deficit?

A calorie deficit is the gap between the energy your body burns each day (TDEE) and the energy you consume through food and drink. When you consistently eat less than you burn, your body draws on stored fat to make up the difference, resulting in gradual, sustainable weight loss.

The size of the deficit determines how quickly you lose weight. Larger deficits produce faster results but increase the risk of muscle loss and nutritional gaps. A moderate deficit of 300–500 kcal/day is widely recommended for most people as the best balance between speed and sustainability.

Frequently asked questions

What is a calorie deficit?
A calorie deficit occurs when you consume fewer calories than your body burns (TDEE) in a given day. Your body makes up the energy shortfall by burning stored fat, which leads to weight loss over time. A consistent daily deficit is the core mechanism behind all evidence-based fat loss strategies.
How many calories are in a pound of fat?
One pound of body fat contains approximately 3,500 calories. This means a cumulative deficit of 3,500 calories is needed to lose roughly one pound. A 500 kcal/day deficit produces a 3,500 kcal/week shortfall, which corresponds to about one pound of fat loss per week.
Is a 1,000 kcal/day deficit safe?
A 1,000 kcal deficit is at the upper limit of what most health professionals recommend. It may be appropriate for individuals with higher TDEE values, but it increases the risk of muscle loss, nutrient deficiencies, and fatigue. Going below 1,200 kcal/day is generally discouraged without medical supervision.
Why does this calculator enforce a 1,200 kcal minimum?
The 1,200 kcal/day floor is a widely cited minimum threshold for meeting basic nutrient needs for most adults. Eating below this level makes it very difficult to obtain adequate protein, vitamins, and minerals, which can impair health and cause muscle loss alongside fat loss.
How do I find my TDEE to use this calculator?
Use the TDEE Calculator on this site. It takes your age, weight, height, and activity level as inputs and applies the Mifflin-St Jeor equation multiplied by your activity factor to produce an accurate daily maintenance calorie estimate.
Will my calorie target need to change as I lose weight?
Yes. As you lose weight, your TDEE decreases because a lighter body requires fewer calories to move and maintain. Recalculate your TDEE and update your deficit target every 4–6 weeks or whenever your weight changes by more than 5 lbs to keep your progress on track.

Related calculators