Is it normal to have grey hair at 20?
Unusual.Less common, but harmless
Gray hair at 20 is less common, but it can happen and is often just down to genetics. A few gray strands on their own usually aren’t a sign that anything is wrong.
It can be surprising to spot gray hair that young, but plenty of people start going gray in their teens or twenties—often because it runs in the family. You might get a few strands, or notice more over time; there’s a wide range of normal.
If the change happens very suddenly or comes with other concerning symptoms, it’s reasonable to ask a healthcare professional about it. Otherwise, it’s usually just one of those personal-timeline things.