JS Built-ins
NumberisNaNbeginner

Number.isNaN() β€” regular number returns false

πŸ“– Usage Example
// Check for NaN without coercion
Number.isNaN(NaN)    // β†’ true
Number.isNaN('NaN')  // β†’ false (no coercion)
Number.isNaN(42)     // β†’ false

Use Number.isNaN() instead of the global isNaN() to check for NaN without coercing the argument first.

Number.isNaN() β€” Regular Numbers

Any real number returns false.

πŸ’‘ Hints (1)
  • β€’ Only the special `NaN` value returns `true` from `Number.isNaN`.