kb/data/developer.mozilla.org/en-US/docs/Glossary/Falsy-0.md

title	chunk	source	category	tags	date_saved	instance
Falsy - Glossary | MDN	1/3	https://developer.mozilla.org/en-US/docs/Glossary/Falsy	reference	web, html, css, javascript, documentation	2026-05-05T05:31:10.056372+00:00	kb-cron

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1. Glossary
2. Falsy

Falsy

A falsy (sometimes written falsey) value is a value that is considered false when encountered in a Boolean context. JavaScript uses type conversion to coerce any value to a Boolean in contexts that require it, such as conditionals and loops. The following table provides a complete list of JavaScript falsy values:

Value	Type	Description
null	Null	The keyword null — the absence of any value.
undefined	Undefined	undefined — the primitive value.
false	Boolean	The keyword false.
NaN	Number	NaN — not a number.
0	Number	The Number zero, also including 0.0, 0x0, etc.
-0	Number	The Number negative zero, also including -0.0, -0x0, etc.
0n	BigInt	The BigInt zero, also including 0x0n, etc. Note that there is no BigInt negative zero — the negation of 0n is 0n.
""	String	Empty string value, also including '' and ````.
document.all	Object	The only falsy object in JavaScript is the built-in document.all.
The values null and undefined are also nullish.

In this article

• Examples
• See also

Examples

Examples of falsy values in JavaScript (which are coerced to false in Boolean contexts, and thus bypass the if block):

The logical AND operator, &&

If the first object is falsy, it returns that object:

See also

• Related glossary terms:
  • Truthy
  • Coercion
  • Boolean
• Boolean coercion