isFinite()
Determines whether a value is a finite number after coercion.
Syntax
isFinite(value)
Returns
boolean — `true` if the coerced value is a finite number.
Examples
console.log(isFinite(42));
console.log(isFinite("100"));
Output
true
true
console.log(isFinite(Infinity));
console.log(isFinite(NaN));
Output
false
false
console.log(isFinite("abc"));
Output
false
Notes
- The global `isFinite()` coerces its argument to a number first.
- Prefer `Number.isFinite()`, which returns `true` only for actual
finite numbers without coercion.
Browser & runtime support
| Environment | Since version |
|---|---|
| chrome | 1.0 |
| firefox | 1.0 |
| safari | 1.0 |
| edge | 12 |
| node | 0.10 |