TRUTHY TOOLS

JavaScript Truthy and Falsy Values

A simple reference table of common JavaScript truthy and falsy values.

Truthy and falsy are about boolean conversion. In JavaScript, some values become false when converted to a boolean. Most other values become true.
Value Result Language Context Example
false Falsy JavaScript The boolean false value. Boolean(false) === false
0 Falsy JavaScript The number zero. Boolean(0) === false
-0 Falsy JavaScript Negative zero is also falsy. Boolean(-0) === false
0n Falsy JavaScript BigInt zero. Boolean(0n) === false
"" Falsy JavaScript An empty string. Boolean("") === false
null Falsy JavaScript A deliberate empty or missing value. Boolean(null) === false
undefined Falsy JavaScript A value that has not been assigned. Boolean(undefined) === false
NaN Falsy JavaScript Not-a-Number. Boolean(NaN) === false
"hello" Truthy JavaScript Any non-empty string is truthy. Boolean("hello") === true
"0" Truthy JavaScript A string containing zero is still a non-empty string. Boolean("0") === true
"false" Truthy JavaScript A string containing the word false is still a non-empty string. Boolean("false") === true
1 Truthy JavaScript Most non-zero numbers are truthy. Boolean(1) === true
-1 Truthy JavaScript Negative non-zero numbers are truthy. Boolean(-1) === true
[] Truthy JavaScript Arrays are objects, and objects are truthy, even when empty. Boolean([]) === true
{} Truthy JavaScript Objects are truthy, even when empty. Boolean({}) === true
function() {} Truthy JavaScript Functions are objects and are truthy. Boolean(function() {}) === true
new Date() Truthy JavaScript Date objects are truthy. Boolean(new Date()) === true
Infinity Truthy JavaScript Infinity is a number value and is truthy. Boolean(Infinity) === true
Useful for JavaScript conditionals, validation, API data checks, automations, and form logic.

About this tool

Truthy Falsy helps developers, QA engineers, technical writers, and support teams reference table of common JavaScript truthy and falsy values. Use it during debugging sessions, documentation updates, code reviews, and integration tests when you need a focused result you can read, copy, or share without opening a heavier application.

Use cases

  • Use Truthy Falsy during debugging when you need to reference table of common JavaScript truthy and falsy values without leaving the browser.
  • Copy Truthy Falsy output into tickets, docs, test notes, spreadsheets, or chat threads so teammates can verify the same result.
  • Keep Truthy Falsy open as a repeatable browser utility for quick checks instead of building a one-off spreadsheet or script.

FAQ

What is Truthy Falsy best used for?

Truthy Falsy is best used when you need to reference table of common JavaScript truthy and falsy values in a fast, copy-friendly browser workflow.

Who benefits most from the Truthy Falsy tool?

It is especially helpful for developers, QA engineers, technical writers, and support teams who handle debugging sessions, documentation updates, code reviews, and integration tests, and need clear output without extra setup.

Can I use Truthy Falsy results in documentation or bug reports?

Yes. The output is designed to be readable and easy to paste into issues, docs, QA notes, or team conversations.