Find what percentage of weight you've lost or gained, your target weight for a percentage goal, or your starting weight — pick what you're solving for below.
Quick answers to the questions people ask most about weight loss percentage.
Subtract your current weight from your starting weight, divide that by your starting weight, then multiply by 100. Going from 200 to 180 is (20 ÷ 200) × 100 = 10% lost.
Multiply your starting weight by the target percentage as a decimal to find the amount, then subtract that from your starting weight. A 10% target on 200 is 20, for a target weight of 180.
Divide your current weight by (1 minus the percentage lost as a decimal). A current weight of 180 after a 10% loss means the starting weight was 180 ÷ 0.90 = 200.
Both measure the same underlying change, just differently. Percentage accounts for body size, so the same 10-pound change is a bigger percentage for a smaller starting weight than a larger one — which is why percentage is often used to compare progress across different people or different starting points.