The 20% Club describes a milestone of losing one fifth of starting body weight. It is not a treatment target everybody needs to reach.
Understand the arithmetic
For a starting weight of 100 kg, 20% is 20 kg. That calculation says nothing by itself about the safest route, the time needed or whether the target suits you. Progress and health are broader than membership of a named milestone.
What you can do next
Use the percentage calculator for context. Pick a suitable goal without making a badge the reason to over-restrict food or change a prescription.
Sources and further reading
Your next step
Explore the relevant guide or tool →
Answer and listed sources checked 2 October 2026.