Weight Loss Percentage Calculator
Last updated October 20, 2026
Short answer: Divide the pounds you lose by your starting weight and multiply by 100. Losing 20 pounds from 200 is 10%, and losing 20 pounds from 300 is about 6.7%. The calculator below does the math for you, and the table shows how many pounds 5%, 10%, 15% and 20% are at common starting weights.
Weight loss percentage calculator
Enter your starting weight, then either a goal weight or the percent you want to lose.
Weight loss percentage
Enter a starting weight between 80 and 800 lbs, then either a goal weight or a percent.
The formula
Percent lost = (starting weight minus current weight) divided by starting weight, times 100. So going from 220 pounds to 198 pounds is 22 pounds lost, and 22 divided by 220 is 10%.
How many pounds is 5%, 10%, 15% and 20%?
| Starting weight | 5% | 10% | 15% | 20% |
|---|---|---|---|---|
| 160 lbs | 8 lbs | 16 lbs | 24 lbs | 32 lbs |
| 180 lbs | 9 lbs | 18 lbs | 27 lbs | 36 lbs |
| 200 lbs | 10 lbs | 20 lbs | 30 lbs | 40 lbs |
| 220 lbs | 11 lbs | 22 lbs | 33 lbs | 44 lbs |
| 250 lbs | 12.5 lbs | 25 lbs | 37.5 lbs | 50 lbs |
| 300 lbs | 15 lbs | 30 lbs | 45 lbs | 60 lbs |
| 350 lbs | 17.5 lbs | 35 lbs | 52.5 lbs | 70 lbs |
The same percentage is more pounds for someone who starts heavier, which is why a goal like "lose 30 pounds" means very different things at 160 pounds and at 350 pounds. Our timeline pages show this for GLP-1 medications.
Why the percentage matters
- The CDC says even modest weight loss can help improve blood pressure, cholesterol and blood sugar. Its example is that 5% of a 200-pound person is 10 pounds.
- Clinical trials report results as a percent of starting weight, so the percentage lets you compare your goal with them.
- Percent loss avoids the problem that a pound means different things at different body weights.
What the trials reported, as percentages
These are the average losses in the trials behind the prescribing labels. Both were in adults with obesity or overweight, with diet and activity counseling.
| Trial | Average loss | Placebo |
|---|---|---|
| Wegovy (2.4 mg), 68 weeks | 14.9% | 2.4% |
| Zepbound 15 mg, 72 weeks | 20.9% | 3.1% |
Individual results varied a lot. See do GLP-1s work? for the share of people who lost at least 5%, 10%, 15% and 20%, and how fast to lose weight for pace.
Sources
Want to see how long reaching a percentage goal could take on a GLP-1?
Try the Free GLP-1 CalculatorMedical Disclaimer
This calculator is for educational and informational purposes only and does not provide medical advice, diagnose any condition, recommend or prescribe treatment, or guarantee results. Estimates are based on information you provide and published clinical-trial averages. Individual results can vary significantly.
Estimates are based on average outcomes reported in the STEP 1 (semaglutide) and SURMOUNT-1 (tirzepatide) clinical trials. Individual results can vary significantly and are influenced by factors such as dosage, diet, and adherence.
Do not start, stop, or change any medication based on the results of this calculator. Always consult a qualified healthcare professional regarding medications, treatment options, risks, side effects, and your individual health needs.