About the Weight Loss Percentage Calculator
Pounds and kilograms tell you how much weight has gone, but a percentage tells you how big that change is for your body. Doctors and clinical studies describe weight loss as a share of starting weight, for example a loss of 5 percent already improves blood pressure and blood sugar for many people. This calculator takes your starting weight and your current weight and gives the percentage lost or gained. If you add a goal weight, it also shows how much of the journey you have completed and how much is left. It works in kilograms, pounds or stone.
Updated October 2026
How to use the Weight Loss Percentage Calculator
- 1Choose your weight unit.
- 2Enter the weight you started at.
- 3Enter your current weight.
- 4Optional: enter your goal weight to see progress toward it.
- 5Read the percentage, the weight change and the share of your goal reached.
Why percentages beat raw numbers
Eight kilograms means something very different to a 60 kg person and a 140 kg person. A percentage puts both on the same scale, which is why research papers and clinics use it. It also lets you compare your progress fairly with other people or with published results.
Tracking progress sensibly
- Weigh at the same time of day, ideally in the morning, on the same scale.
- Use a weekly average rather than a single reading, because daily weight swings by 1 to 2 kg.
- Record waist measurements too, since fat can fall while the scale stands still.
- Celebrate milestones at 5 and 10 percent, which are linked to health gains.
What to read next
Combine this with the Calorie Deficit Calculator to plan how long your goal will take, the BMI Calculator to see where your weight sits for your height and the Ideal Weight Calculator to choose a realistic target. Percentages also appear in the Percentage Calculator if you need a quick everyday sum.
Features
- Percent of body weight lost or gained
- Kilograms, pounds and stone
- Optional goal weight with percent of goal reached
- Shows the weight still to go
- Handles weight gain without errors
- Free and private
Frequently asked questions
How do I calculate the percentage of weight lost?
Subtract your current weight from your starting weight, divide by the starting weight and multiply by 100. Going from 90 kg to 82 kg is 8 kg lost, and 8 divided by 90 is 8.9 percent. The same method works in pounds or stone.
Is a 5 percent weight loss meaningful?
Yes. Clinical research shows that losing 5 to 10 percent of body weight can lower blood pressure, improve cholesterol and reduce the risk of type 2 diabetes in people with excess weight. Larger losses bring larger benefits for some conditions.
What is a healthy rate of weight loss?
Many health bodies suggest about 0.5 to 1 percent of your body weight a week. For an 80 kg person that is 400 to 800 grams. Faster losses happen early on, mostly from water, and are harder to keep up.
Is the percent of goal the same as percent of body weight?
No. Percent of body weight compares your loss with your starting weight. Percent of goal compares it with the total you planned to lose. Losing 8 kg of a planned 16 kg is 50 percent of your goal but only 8.9 percent of a 90 kg body weight.
Why does my percentage look small?
Percentages are based on your whole body weight, so even a large number of kilograms can look modest. Someone who starts at 120 kg and loses 12 kg has lost 10 percent. That is a strong result, even if the number looks small.
Can I use this for weight gain?
Yes. If your current weight is higher than your starting weight, the calculator reports the percentage gained instead. That is handy for athletes building up, for people recovering from illness or for tracking pregnancy gain.