Strings

Uncapitalize

Lower-cases the first character and leaves the rest alone.

What it is

The inverse of `Capitalize`, and the one you need when going the other way: turning `getName` back into `name`, or an event type `Click` into the handler key `onClick`’s payload name. Less used than its mirror, and for exactly that reason more often forgotten to exist.

Examples

```
Uncapitalize<'Name'>
```
→"name"
```
Uncapitalize<'HELLO'>
```
→"hELLO"
```
Uncapitalize<Capitalize<'name'>>
```
→"name"
They compose back to where you started, for a first character that had a case to begin with.

Each resolved type above was printed by TypeScript 5.9.3, not written by hand.

What it does not do

It does not lower-case the whole string, which `Uncapitalize<"HELLO">` makes uncomfortably clear.
It is not a round trip in general. Only the first character is affected, so any information lost elsewhere stays lost.

Takeaway

Reach for it when deriving a property name back out of a method name — the inverse direction is where the missing key usually comes from.