What's the minimum calories I should eat?

Most guidelines suggest no less than 1,200 calories/day for women and 1,500 for men. Below these levels, it becomes very difficult to meet nutritional needs and muscle loss accelerates.

How many calories to gain muscle?

A surplus of 200–500 calories above TDEE supports lean muscle gain. Larger surpluses primarily add fat. Beginners can sometimes gain muscle even in a slight deficit (body recomposition).

Why does the 12-week projection slow down?

As you lose weight, your BMR decreases because there's less body to maintain. The projection accounts for this, which is why your weight loss rate may slow over time even with the same calorie target.

Is a 1,000 calorie deficit safe?

A 1,000 calorie deficit (2 lbs/week) is at the aggressive end and only appropriate for heavier individuals. For most people it risks muscle loss, fatigue, and metabolic adaptation. Aim for 500 cal/day max.

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Calorie Deficit Calculator

Calculate your daily calorie target for weight loss, muscle gain, or maintenance. Set your goal rate of change and see a 12-week weight projection.

Last updated: April 13, 2026

How to Use This Calculator

Enter your sex, age, height, weight, and activity level.
Select your goal: weight loss, maintenance, or muscle gain.
For weight loss or gain, choose your weekly rate of change (0.5–2 lbs/week).
Review your daily calorie target and the 12-week weight projection.

Real-World Examples

Moderate Weight Loss

40-year-old woman, 5'5", 180 lbs, lightly active. Goal: lose 1 lb/week.

Result: TDEE ≈ 2,011 kcal. Daily target: 1,511 kcal. 12-week projected loss: ~11.5 lbs.

Lean Bulk

24-year-old man, 6'0", 155 lbs, very active. Goal: gain 0.5 lbs/week.

Result: TDEE ≈ 3,285 kcal. Daily target: 3,535 kcal (+250 surplus). 12-week projected gain: ~5.5 lbs.

Common Mistakes to Avoid

Setting an overly aggressive deficit that leads to rapid muscle loss and metabolic slowdown.
Not adjusting the calorie target every 4–6 weeks as bodyweight changes.
Tracking calories inconsistently — even small errors (e.g., cooking oils, sauces) add up to 200–400 extra calories per day.
Relying on exercise to create the entire deficit instead of combining diet and activity changes.

The Formula

Weight loss: Daily calories = TDEE − (weekly rate × 500). Muscle gain: Daily calories = TDEE + surplus (capped at 500 cal/day). 1 lb of fat ≈ 3,500 calories, so a 500 cal/day deficit = 1 lb/week loss.

Learn More

Health

How to Calculate Calorie Deficit for Weight Loss (Step by Step)

Step-by-step: find your TDEE, subtract 500, and track progress.

April 13, 2026 Health

How Many Calories Should I Eat to Lose 1 Pound Per Week?

A 500 cal/day deficit = 1 lb/week. Here's how to make it work.

April 13, 2026

Frequently Asked Questions

A deficit of 250–500 calories/day is considered safe for most adults. This produces 0.5–1 lb of weight loss per week while minimizing muscle loss. Deficits larger than 1,000 cal/day are not recommended without medical supervision.