The formula
Weight loss percentage = (starting weight − current weight) ÷ starting weight × 100.
If you started at 220 pounds and now weigh 198, you have lost 22 pounds, and 22 ÷ 220 × 100 = 10%.
Why 5% and 10% are useful milestones
Health guidance often talks about weight loss as a share of body weight rather than a number of pounds, because the same number means more for a smaller person. The CDC notes that even a modest loss can improve blood pressure, cholesterol and blood sugar, using 5% of a 200 pound person's weight, or 10 pounds, as an example. Medication trials and doctors also report results as a percentage, which is why you will often see figures like 10% or 15%.
Want to know when you'll reach the next milestone? The weight loss timeline calculator shows how long it takes to lose your first 5% and 10%.
Questions people ask
How do you calculate weight loss percentage?
Subtract your current weight from your starting weight, divide by your starting weight, and multiply by 100. For example, going from 200 to 180 pounds is 20 divided by 200, or 10%.
Why track weight loss as a percentage?
A percentage makes progress comparable between people of different sizes. Losing 10 pounds is 5% for someone who starts at 200 pounds but about 7% for someone who starts at 150. Doctors and research studies usually report weight loss this way.
What percentage of weight loss matters for health?
The CDC notes that even modest weight loss can improve blood pressure, cholesterol and blood sugar, giving the example that 5% of a 200 pound person's weight is 10 pounds.
Does the unit matter?
No. The percentage is the same in pounds or kilograms, as long as both weights use the same unit.
Sources
- Centers for Disease Control and Prevention. Losing Weight.