Weight Loss Percentage Calculator
Work out what percentage of your body weight you've lost, and your progress towards a goal.
About the Weight Loss Percentage Calculator
Enter your starting weight, current weight and, if you have one, a goal, in kilograms, pounds or stone. The calculator shows the percentage lost and how far you are towards your goal.
Percentage weight loss lets people of different sizes compare progress and is how clinical trials report results. Health guidance from the NHS and CDC notes that losing 5–10% of body weight can improve blood pressure, cholesterol and blood sugar. A steady rate of about 0.5–1 kg (1–2 lb) a week is commonly recommended.
The formula
Weight loss % = (start − current) ÷ start × 100
Worked example
Started at 100 kg, now 93 kg, aiming for 82 kg
- Lost: 100 − 93 = 7 kg
- 7 ÷ 100 = 7% of starting weight
- Progress to goal: 7 ÷ 18 = 39%
Things to keep in mind
- Weigh at the same time of day in similar clothes; daily swings of 1–2 kg are normal.
- Weight doesn't show changes in muscle and fat; waist measurement adds useful context.
Questions people ask
Is 1% a week too fast?
Around 0.5–1% a week is a common safe range for most adults.
Why do I weigh more some days?
Water, salt and food in the gut shift weight by 1–2 kg day to day.
How much is 5% for me?
Multiply your starting weight by 0.05: from 90 kg, 5% is 4.5 kg.