Different between == and === in JavaScript examples

In this tutorial, We will have a look, at the difference between == and === in javascript with code examples.

This post covers examples and notes about the comparison of double equal signs(==) and triple equal signs(===) operators in JavaScript.

First, what do equal signs about?

Both operators are used to compare different values.

== is called an equality operator, which applies type coercion, what doe type coercion, It converts the values before comparison.

m==n returns true if m and n are the same values and types, else false.

=== is called identity operators, which do not apply type coercion, not converting the values before conversion.

m===n returns true, if m and n are the same values for strings and the same reference for objects, else false.

Javascript Equal operators(== and ===) Examples

Here are some examples of double equal and three equal operator examples

5 == "5" - true;
5 === "5" - false;

"0" == undefined; // true
"0" === undefined; // false

null == undefined; // true
null === undefined; // false

In the above examples,

5==“5”, Comparing number and string, and converted to the same type, i.e numbers, with == checks value(5==5) and type(numbers) are same, returns true. 5===“5” return false as both operands are different(integer and string)

javascript Comparision between == vs === operators

Both operators are applied to two operands or variables.

== operator=== operators
Called Comparison operatorStrict comparison operator
compared two operands or variables, the data type is ignoredcompared two operands or variables and data type
Returns true, if values are equal, false not equalReturns true, if values and types are equal, false both not equal
durationtime in milliseconds shown before disappearing from the page
type coercion before comparisontype coercion ignored before comparison