See exactly how much body weight you've lost — instantly.
Your Weights
Optional — for more detail
Results
Body Weight Lost
You lost 15.0 lbs from your starting weight of 200.0 lbs
Excellent — clinically significant weight loss!
Formula: Weight Loss % = ((Starting Weight − Current Weight) ÷ Starting Weight) × 100. This expresses how much of your original body weight you have lost. A loss of 5–10% of body weight is considered clinically significant and is associated with meaningful health improvements.
The Weight Loss Percentage Calculator tells you exactly what fraction of your starting body weight you have shed — a far more meaningful metric than raw pounds or kilograms alone. Enter your starting weight and current weight to get your percentage instantly. Optionally add your goal weight to track progress and your height to compare BMI before and after your journey.
Divide the amount of weight lost (starting weight minus current weight) by your starting weight, then multiply by 100. For example, losing 15 lbs from a starting weight of 200 lbs equals (15 ÷ 200) × 100 = 7.5%.
Research consistently shows that losing just 5–10% of your starting body weight is considered clinically significant. Even at this level, improvements in blood pressure, blood sugar, and cholesterol are commonly observed.
Percentage normalizes weight loss relative to your starting size, making it easier to compare progress with others, set realistic targets, and evaluate health impact — a 20 lb loss means very different things depending on whether you started at 150 lbs or 300 lbs.
No. All calculations happen entirely in your browser. No weight data is sent to any server or stored anywhere.