Weight Loss Percentage Calculator
Weight change as a percentage of starting weight — the measure that makes progress comparable regardless of where you started.
Percentage change is (start − current) ÷ start.
How the weight loss percentage calculator works
Percentage change is (start − current) ÷ start. It matters because absolute numbers are not comparable: losing 5 kg from 60 kg is a far larger change than 5 kg from 130 kg.
The clinically meaningful thresholds are percentages too. A 5% loss produces measurable improvements in blood pressure and glucose control; 10% is the target most guidelines set for metabolic benefit.
Formula: % change = (start − current) / start × 100
Worked examples
| Inputs | Weight change | Note |
|---|---|---|
| 95 kg down to 88 kg | 7.37% | 7.4% — past the 5% milestone |
| A 10% loss | 10% | exactly 10% |
| Weight gained | -7.95% | negative percentage |
FAQFrequently asked questions
Why use a percentage rather than kilograms?
Because it makes progress comparable. Losing 5 kg means something very different at 60 kg than at 130 kg.
What percentage loss is clinically meaningful?
5% produces measurable improvements in blood pressure, blood glucose and lipids. 10% is the target most guidelines set.
How fast should weight come off?
Around 0.5 to 1% of body weight a week is the usual guideline. Faster loss tends to include more lean mass and is harder to sustain.
Why has my loss stalled?
A smaller body burns fewer calories, so the same intake that once produced a deficit eventually does not. It is arithmetic, not failure.
Does this account for body composition?
No — it tracks total weight. Losing fat while gaining muscle can show almost no change on the scale despite real progress.
Where these figures come from
- Mifflin MD et al., "A new predictive equation for resting energy expenditure in healthy individuals", Am J Clin Nutr 1990 — the BMR equation used here
- World Health Organization — Waist circumference and waist–hip ratio (2008 expert consultation) — waist-to-hip cut-offs
- Tanaka H, Monahan KD, Seals DR, "Age-predicted maximal heart rate revisited", J Am Coll Cardiol 2001 — 208 − 0.7 × age
- Nathan DM et al., "Translating the A1C assay into estimated average glucose values" (ADAG), Diabetes Care 2008 — eAG = 28.7 × A1c − 46.7
- Mosteller RD, "Simplified calculation of body-surface area", N Engl J Med 1987 — BSA = √(height × weight / 3600)
- Centers for Disease Control and Prevention — national health guidance
Last checked: September 2026. The equations are fixed by their published papers and do not change with tax years or regulations; the thresholds quoted in verdicts name the body that set them.