Logical OR Operator (||) (JavaScript)

Performs a logical disjunction on two expressions.


result = expression1 || expression2  


Any variable.

Any expression.

Any expression.


If either or both expressions evaluate to True, result is True. The following table illustrates how result is determined:

If expression1 is And expression2 is The result is
True True True
True False True
False True True
False False False

JavaScript uses the following rules for converting non-Boolean values to Boolean values:

  • All objects are considered true.

  • Strings are considered false if and only if they are empty.

  • null and undefined are considered false.

  • Numbers are false if, and only if, they are 0.


Supported in the following document modes: Quirks, Internet Explorer 6 standards, Internet Explorer 7 standards, Internet Explorer 8 standards, Internet Explorer 9 standards, Internet Explorer 10 standards, Internet Explorer 11 standards. Also supported in Store apps (Windows 8 and Windows Phone 8.1). See Version Information.

See Also

Operator Precedence
Operator Summary (JavaScript)