Transparent method
The formula
Worked example
Example inputs
How to interpret the result
The 3,500-calories-per-pound figure behind most calorie-goal math is a population average, not a fixed physical law that applies identically to every body, so a consistent daily deficit doesn't translate into weight loss on a perfectly linear schedule. Actual results vary with water retention, hormones and metabolic adaptation that the simple arithmetic doesn't model.
Before you rely on it
What to check
Use the goal as a starting plan and adjust based on actual weekly results over several weeks, not the calorie math projecting a specific date.
The common error
Where people go wrong with calorie goal calculator
Expecting the calculator's weekly-change estimate to land exactly on schedule every week. Short-term fluctuation is normal, and judging the plan by any single week's result rather than the multi-week trend leads to unnecessary second-guessing.
Sensitivity evidence
How weight changes the target daily calories
| Weight | Target daily calories | Estimated weekly weight change |
|---|---|---|
| 136 | 1,912.4 | -0.956 |
| 153 | 2,008 | -1 |
| 170worked example | 2,103.6 | -1.1 |
| 187 | 2,199.3 | -1.1 |
| 204 | 2,294.9 | -1.1 |
Every input, tested
Which input moves the target daily calories most
| Input | Tested from | To | Target daily calories at each end | Swing |
|---|---|---|---|---|
| Activity level | Sedentary | Very active | 1,628.6 to 2,578.7 | 950 (45%) |
| Goal | Cut, 20% deficit | Bulk, 20% surplus | 2,103.6 to 3,155.5 | 1,051.8 (50%) |
| Height | 62 | 76 | 1,965.8 to 2,241.4 | 275.6 (13%) |
| Sex | Male | Female | 2,103.6 to 1,897.8 | 205.8 (9.8%) |
| Weight | 153 | 187 | 2,008 to 2,199.3 | 191.2 (9.1%) |
| Age | 26.0 years | 44.0 years | 2,159.4 to 2,047.8 | 111.6 (5.3%) |
Two variables at once
Target daily calories by weight and height
| Weight \ Height | 55 | 69 | 83 |
|---|---|---|---|
| 136 | 1,636.8 | 1,912.4 | 2,188 |
| 153 | 1,732.4 | 2,008 | 2,283.6 |
| 170 | 1,828 | 2,103.6 | 2,379.2 |
| 187 | 1,923.7 | 2,199.3 | 2,474.8 |
| 204 | 2,019.3 | 2,294.9 | 2,570.5 |
Step by step
The worked example, input by input
| Input | Value used | What it means |
|---|---|---|
| Sex | Male | The underlying BMR formula uses a different constant by sex. |
| Weight | 170 | Body weight in pounds. |
| Height | 69 | Height in inches. |
| Age | 35.0 years | Age in years. |
| Activity level | Moderate | Typical weekly activity level. |
| Goal | Cut, 20% deficit | Percent below (cut) or above (bulk) maintenance calories. |
| Target daily calories | 2,103.6 | |
| Estimated weekly weight change | -1.1 | |
Inputs, definitions and assumptions
Sex
The underlying BMR formula uses a different constant by sex.
Weight
Body weight in pounds.
Height
Height in inches.
Age
Age in years.
Activity level
Typical weekly activity level.
Goal
Percent below (cut) or above (bulk) maintenance calories.
Where the inputs come from
Enter your sex, weight, height, age and activity level to estimate maintenance calories, then choose a goal as a percentage: a negative number for weight loss, such as minus 20 for a 20% deficit, and a positive number for gain. Modest changes of 10% to 20% are easier to sustain and preserve muscle better than crash diets. The tool converts the daily gap into an estimated weekly change using the approximation of 3,500 calories per pound.
When the result stops applying
The pound-per-3,500-calories rule overestimates long-term weight change because metabolism adapts and water shifts mask fat loss. Very low calorie intakes can cause muscle loss, nutrient deficiencies and gallstones and should be done only with medical supervision. Many guidelines advise not going below about 1,200 calories for women or 1,500 for men without a clinician's help. Pregnant and breastfeeding women have different needs.
What to compare it with
See maintenance on the TDEE calculator, protein and macronutrient targets on those pages, and the timeline on the weight loss time calculator. The BMI and healthy weight range pages set context for goals. Include strength training to preserve lean mass.
People also ask
Frequently asked questions
How many calories should I cut to lose weight?
A deficit of 10% to 20% of maintenance, roughly 300 to 500 calories a day for many people, is a common and sustainable starting point.
How fast is it safe to lose weight?
About 0.5 to 2 pounds a week for most people. Faster loss increases muscle loss and is best done only under medical supervision.
Why did my weight loss stall?
Your body burns fewer calories at a lower weight and adapts to reduced intake, so recalculate your needs and reassess your habits.