Skip to content
GlobalCalculator

Weight Loss Percentage Calculator

Percentage of body weight lost, weekly rate and progress toward a goal weight.

Your details

How the weight loss percentage calculator works

Percentage is the fairer progress measure because the same 5 kg means far more at 60 kg than at 120 kg. Losing 5-10% of body weight already brings measurable health benefits.

Formula

% lost = (start weight − current weight) ÷ start weight × 100

Worked example

Dropping from 92 kg to 84.5 kg is an 8.15% loss, averaging 0.63 kg a week.

Frequently asked questions

What is a safe rate?

Around 0.5-1% of body weight per week is the usual guidance for sustainable loss.

Does the unit matter?

No — the percentage is identical whether you enter kilograms or pounds, as long as both figures use the same unit.

Weight Loss Percentage: The Fairest Way to Measure Progress

Percentage of body weight lost equals weight lost divided by starting weight, times 100. It is a fairer measure than kilograms because the same loss represents very different effort and physiological change at different body sizes.

The calculations

  • Percent lost = (start − current) ÷ start × 100.
  • Weekly rate = total lost ÷ weeks elapsed.
  • Progress to goal = lost ÷ (start − goal) × 100.
  • The unit cancels — kilograms and pounds give an identical percentage.

What 5% and 10% actually deliver

Clinical guidance repeatedly identifies 5-10% of body weight as the threshold where measurable benefits appear: improved blood pressure, better insulin sensitivity, lower triglycerides and reduced sleep apnoea severity. That makes a modest, sustained percentage a more useful target than a round number on the scale.

Reading the trend, not the reading

  • Weigh at the same time of day under the same conditions.
  • Track a seven-day rolling average; daily fluctuation is mostly water and food volume.
  • A stall of one to two weeks is normal, especially around hormonal cycles.
  • 0.5-1% of body weight per week is the usual guidance for sustainable loss.

Key takeaways — Weight Loss Percentage Calculator

  • % lost = (start − current) ÷ start × 100, unit-independent.
  • 5-10% loss produces measurable health improvements.
  • Judge progress on a weekly average, not a single morning's reading.

More health calculators