When using boolean coercion, the following values are considered “falsy”:

• false
• 0
• "" (empty string)
• null
• undefined
• NaN (not a number, e.g. 0/0)
• document.all¹ (browser context)

Everything else is considered “truthy”.

Abstract equality inequality and type conversion

NaN Property of the Global Object

Short-circuiting in boolean operators

Double Negation (!!)

Abstract equality

Bitwise operators

Null and undefined

Automatic Type Conversions

Logic Operators with Non-boolean values boolean coercion

Empty Array