Weight Loss Percentage Calculator

Calculate the percentage of body weight lost from a starting weight. Add an optional goal weight to see how much of the planned change is complete and how much remains.

Enter your weights

Your progress

Weight loss percentage8.9%You have lost 8 kg from your starting weight.
Weight lost8 kg
Current change−8.9%
Goal progress50%
Remaining to goal8 kg

50% of the planned weight change completed.

How weight loss percentage is calculated

Subtract current weight from starting weight, divide the difference by starting weight, then multiply by 100. For example, changing from 90 kg to 82 kg is a loss of 8 kg, or approximately 8.9% of the starting weight.

Understanding goal progress

When a goal is entered, progress is the weight already lost divided by the total planned loss. The progress indicator is capped visually at 100%, while the numeric result can show progress beyond the original goal.

Can the calculator show weight gain?

Yes. If current weight is higher than starting weight, the calculator reports the gain and a positive percentage change.

Which unit should I use?

Use kilograms or pounds consistently. Percentage results are identical because the calculation uses a ratio.

How often should I compare weight?

Body weight naturally fluctuates. Similar timing and conditions make comparisons more meaningful, and longer-term trends are usually more useful than daily changes.

Health notice: Rapid or unexplained weight changes can require professional evaluation. This calculator provides general information, not medical advice.