JavaScript Comparison Operators

JavaScript comparison operators are used to compare two values and determine the relationship between them. They are an important part of JavaScript because programs constantly need to make decisions based on whether values are equal, different, greater, or smaller.

For example, you might want to check whether a user’s age is 18 or above, whether two passwords match, whether a product price is below a certain amount, or whether a score has reached a required value. Comparison operators make these checks possible.

The result of a comparison is always a Boolean value, which means JavaScript returns either true or false.

let age = 20;

console.log(age >= 18);

Output:

true

In this tutorial, you will learn all the commonly used JavaScript comparison operators:

• ==
• ===
• !=
• !==
• >
• <
• >=
• <=

You will also learn the important difference between loose equality (==) and strict equality (===), which is one of the most important concepts for JavaScript beginners.

What Are Comparison Operators in JavaScript?

Comparison operators compare two values and return a Boolean result.

For example:

let a = 10;
let b = 20;

console.log(a < b);

Output:

true

JavaScript checks whether 10 is less than 20. Because the statement is true, the result is true.

If the comparison is not correct:

console.log(a > b);

Output:

false

Comparison operators are commonly used inside:

• if statements
• else statements
• loops
• functions
• validation
• form checking
• filtering
• searching
• application logic
• games
• calculations

JavaScript Comparison Operators List

JavaScript provides several comparison operators for checking equality and relationships between values.

Operator	Name	Example	Result
==	Loose equality	5 == "5"	true
===	Strict equality	5 === "5"	false
!=	Loose inequality	5 != "5"	false
!==	Strict inequality	5 !== "5"	true
>	Greater than	10 > 5	true
<	Less than	5 < 10	true
>=	Greater than or equal to	10 >= 10	true
<=	Less than or equal to	10 <= 10	true

The first four operators are mainly concerned with equality and inequality, while the last four compare the relative size or ordering of values.

The == Loose Equality Operator

The == operator is called the loose equality operator.

It checks whether two values are equal after JavaScript performs certain type conversions when necessary.

For example:

let number = 10;

console.log(number == 10);

Output:

true

The values have the same number and type, so the comparison is true.

However, == can also return true when the two operands have different types.

console.log(10 == "10");

Output:

true

Here, one value is a number and the other is a string. JavaScript performs type coercion as part of the loose equality comparison.

Another Example of ==

console.log(5 == "5");

Output:

true

The string "5" is converted for the comparison, so JavaScript considers the values equal.

Why == Can Be Confusing

Consider:

console.log(0 == false);

Output:

true

And:

console.log("" == false);

Output:

true

These results happen because loose equality allows type coercion.

For beginners, this can sometimes make code harder to predict. That is one reason strict equality with === is commonly preferred when you want the comparison to include both value and type.

The === Strict Equality Operator

The === operator is called the strict equality operator.

It checks both the value and the data type of the operands.

console.log(10 === 10);

Output:

true

Both operands are numbers and have the same value.

Now consider:

console.log(10 === "10");

Output:

false

Although both values represent 10, their data types are different.

The first value is a number:

10

The second value is a string:

"10"

Because strict equality does not perform the same type coercion as ==, the result is false.

Comparing Strings with ===

let username = "John";

console.log(username === "John");

Output:

true

But:

console.log(username === "john");

Output:

false

String comparisons are case-sensitive.

Comparing Booleans with ===

let loggedIn = true;

console.log(loggedIn === true);

Output:

true

But:

console.log(loggedIn === "true");

Output:

false

The first value is a Boolean, while "true" is a string.

== vs ===

The difference between == and === is extremely important in JavaScript.

Feature	==	===
Name	Loose equality	Strict equality
Compares value	Yes	Yes
Checks type	Not in the same strict way	Yes
Performs type coercion	Yes, when required	No
10 == "10"	true	false
Common use	When coercion is intentionally desired	When exact equality is required

For example:

console.log(10 == "10");

Result:

true

But:

console.log(10 === "10");

Result:

false

For most application code, === is often easier to reason about because it does not silently treat different types as equal.

The != Loose Inequality Operator

The != operator checks whether two values are not equal, using the loose equality rules.

For example:

console.log(10 != 20);

Output:

true

Because 10 and 20 are different.

Now consider:

console.log(10 != "10");

Output:

false

The values are treated as equal under loose equality, so the inequality comparison returns false.

The expression:

x != y

is related to:

!(x == y)

in terms of its loose equality semantics.

Example with Variables

let age = 25;

console.log(age != 18);

Output:

true

The value 25 is not equal to 18.

The !== Strict Inequality Operator

The !== operator is called the strict inequality operator.

It checks whether two values are different in value or type.

console.log(10 !== 20);

Output:

true

The values are different.

More importantly:

console.log(10 !== "10");

Output:

true

The values have different types, so strict inequality returns true.

!= vs !==

Expression	Result
10 != "10"	false
10 !== "10"	true
10 != 20	true
10 !== 20	true

The difference comes from type coercion.

!= uses loose comparison rules, while !== performs strict comparison.

The > Greater Than Operator

The > operator checks whether the value on the left is greater than the value on the right.

console.log(10 > 5);

Output:

true

Because 10 is greater than 5.

If the left value is smaller:

console.log(5 > 10);

Output:

false

Using > with Variables

let age = 25;

console.log(age > 18);

Output:

true

This type of comparison is useful when checking minimum requirements or limits.

For example:

let marks = 75;

if (marks > 40) {
    console.log("Pass");
}

Output:

Pass

Notice that 75 > 40 is true, so the code inside the if block runs.

The < Less Than Operator

The < operator checks whether the value on the left is less than the value on the right.

console.log(5 < 10);

Output:

true

Because 5 is less than 10.

If the left value is greater:

console.log(10 < 5);

Output:

false

Example with Variables

let price = 50;

console.log(price < 100);

Output:

true

This can be useful for checking whether a price is below a particular limit.

The >= Greater Than or Equal To Operator

The >= operator checks whether the left value is either greater than or equal to the right value.

console.log(10 >= 5);

Output:

true

It also returns true when both values are equal.

console.log(10 >= 10);

Output:

true

But:

console.log(5 >= 10);

Output:

false

Practical Example

Suppose a website requires users to be at least 18 years old.

let age = 18;

if (age >= 18) {
    console.log("Access allowed");
}

Output:

Access allowed

Using >= is appropriate because an age of exactly 18 should also satisfy the condition.

The <= Less Than or Equal To Operator

The <= operator checks whether the left value is less than or equal to the right value.

console.log(5 <= 10);

Output:

true

It also returns true when the values are equal.

console.log(10 <= 10);

Output:

true

But:

console.log(15 <= 10);

Output:

false

Practical Example

Suppose you want to check whether a product is within a budget of ₹1,000.

let price = 950;

if (price <= 1000) {
    console.log("Within budget");
}

Output:

Within budget

Comparison Operators Return Boolean Values

All comparison operators return either true or false.

console.log(10 > 5);
console.log(10 < 5);
console.log(10 === 10);
console.log(10 !== 20);

Output:

true
false
true
true

You can also check the type of the result:

let result = 10 > 5;

console.log(result);
console.log(typeof result);

Output:

true
boolean

This is because comparison expressions produce Boolean values.

Using Comparison Operators with if

Comparison operators are especially useful with conditional statements.

let age = 20;

if (age >= 18) {
    console.log("You are an adult.");
}

Output:

You are an adult.

The expression:

age >= 18

returns true, so JavaScript executes the code inside the if block.

Using else

let age = 16;

if (age >= 18) {
    console.log("You are an adult.");
} else {
    console.log("You are under 18.");
}

Output:

You are under 18.

Comparison operators therefore play an important role in controlling how a program behaves.

Comparing Numbers

Number comparisons are straightforward.

let a = 25;
let b = 10;

console.log(a > b);
console.log(a < b);
console.log(a >= b);
console.log(a <= b);
console.log(a === b);
console.log(a !== b);

Output:

true
false
true
false
false
true

These comparisons can be used for calculations, validation, scores, prices, quantities, and many other situations.

Comparing Strings

JavaScript can also compare strings.

console.log("apple" === "apple");

Output:

true

But:

console.log("apple" === "Apple");

Output:

false

The comparison is case-sensitive.

JavaScript also supports relational comparisons between strings based on their Unicode code unit values.

console.log("apple" < "banana");

Output:

true

For simple alphabetic comparisons this may appear similar to dictionary ordering, but string comparison in JavaScript follows Unicode-based ordering rules rather than a language-aware dictionary comparison.

Comparing Strings and Numbers

This is an area where beginners should be careful.

With loose equality:

console.log(10 == "10");

Output:

true

With strict equality:

console.log(10 === "10");

Output:

false

Relational operators such as < and > can also convert values when appropriate.

console.log("10" > 5);

Output:

true

The string "10" is converted to a numeric value for this relational comparison.

When working with user input, it is often clearer to convert values explicitly before performing calculations or comparisons.

let age = Number("20");

console.log(age >= 18);

Output:

true

Comparing null and undefined

JavaScript has special values called null and undefined, and comparisons involving them can sometimes produce surprising results.

For example:

console.log(null == undefined);

Output:

true

But:

console.log(null === undefined);

Output:

false

This happens because loose equality has special rules for null and undefined, while strict equality requires the same type.

For exact checks, use strict equality:

value === null

or:

value === undefined

Comparing NaN

NaN means Not-a-Number.

An important JavaScript behavior is that NaN is not equal to itself.

console.log(NaN === NaN);

Output:

false

It also does not equal itself with loose equality:

console.log(NaN == NaN);

Output:

false

To check whether a value is specifically NaN, use:

Number.isNaN(value);

For example:

let result = Number("hello");

console.log(Number.isNaN(result));

Output:

true

Comparing Boolean Values

Boolean values can also be compared.

console.log(true === true);

Output:

true

And:

console.log(false === true);

Output:

false

It is important to remember that:

true

is a Boolean, while:

"true"

is a string.

Therefore:

console.log(true === "true");

Output:

false

Comparison Operators in Loops

Comparison operators are commonly used to control loops.

For example:

for (let i = 1; i <= 5; i++) {
    console.log(i);
}

Output:

1
2
3
4
5

The condition:

i <= 5

is checked before each iteration.

As long as the comparison returns true, the loop continues.

Comparison Operators in Form Validation

Comparison operators are frequently used when validating user input.

For example:

let age = 21;

if (age >= 18) {
    console.log("You can continue.");
} else {
    console.log("You must be at least 18.");
}

Another example can check a password length:

let password = "JavaScript123";

if (password.length >= 8) {
    console.log("Password length is valid.");
}

Comparison operators therefore help applications enforce rules and requirements.

Comparison Operators in Games

Games often use comparisons to determine whether a player has achieved a particular score.

let score = 1200;

if (score >= 1000) {
    console.log("New level unlocked!");
}

Another example:

let health = 0;

if (health <= 0) {
    console.log("Game Over");
}

These simple comparisons can control important game events.

Equality Operators vs Relational Operators

JavaScript comparison operators can be grouped into two broad categories.

Equality and Inequality

These operators check whether values are equal or different:

==
===
!=
!==

Relational Operators

These operators check the relationship between values:

>
<
>=
<=

Category	Operators	Purpose
Equality	==, ===	Check whether values are equal
Inequality	!=, !==	Check whether values are different
Greater/Less	>, <	Compare relative size
Inclusive comparison	>=, <=	Compare size including equality

Common Mistakes with Comparison Operators

Confusing = with ==

The = operator assigns a value.

let age = 20;

The == operator compares values.

age == 20;

The === operator performs a strict comparison.

age === 20;

These operators should not be treated as interchangeable.

Using == When You Need an Exact Comparison

Consider:

console.log(10 == "10");

This returns:

true

If you need both the value and type to match, use:

console.log(10 === "10");

which returns:

false

Confusing != with !==

These operators have different comparison behavior.

console.log(10 != "10");

returns:

false

while:

console.log(10 !== "10");

returns:

true

Using the Wrong Inclusive Operator

If a condition should include the boundary value, use >= or <=.

For example, if a person must be at least 18:

age >= 18

is different from:

age > 18

With >, an age of exactly 18 would not satisfy the condition.

Best Practices for JavaScript Comparison Operators

Use === when you want a strict equality comparison.

if (userRole === "admin") {
    console.log("Admin access");
}

Use !== when you want strict inequality.

if (status !== "active") {
    console.log("Account is not active.");
}

Use >= and <= when boundary values should also be accepted.

if (marks >= 40) {
    console.log("Pass");
}

Be careful when comparing values that come from forms or other external sources because they may be strings.

Instead of relying on implicit conversion:

let age = "20";

consider explicitly converting the value:

let age = Number("20");

if (age >= 18) {
    console.log("Eligible");
}

Choose comparison operators based on the exact rule your program needs to implement.

JavaScript Comparison Operators Cheat Sheet

Operator	Meaning	Example	Result
==	Equal after type coercion when applicable	5 == "5"	true
===	Strictly equal	5 === "5"	false
!=	Not equal using loose comparison	5 != "5"	false
!==	Strictly not equal	5 !== "5"	true
>	Greater than	10 > 5	true
<	Less than	5 < 10	true
>=	Greater than or equal to	10 >= 10	true
<=	Less than or equal to	10 <= 10	true

A Practical Example Using Comparison Operators

The following example uses several comparison operators in a simple student result program.

let marks = 75;

if (marks >= 90) {
    console.log("Grade A");
} else if (marks >= 75) {
    console.log("Grade B");
} else if (marks >= 40) {
    console.log("Pass");
} else {
    console.log("Fail");
}

Output:

Grade B

The program checks the student’s marks against different values and executes the appropriate block.

Another example can check a user’s age and account status:

let age = 22;
let accountStatus = "active";

if (age >= 18 && accountStatus === "active") {
    console.log("Access granted");
} else {
    console.log("Access denied");
}

Here, comparison operators are combined with a logical operator to create a more complete condition.

Frequently Asked Questions

What are comparison operators in JavaScript?

Comparison operators are used to compare two values. They return either true or false.

Common comparison operators include ==, ===, !=, !==, >, <, >=, and <=.

What is the difference between == and ===?

== performs loose equality comparison and can perform type coercion.

10 == "10"

returns true.

=== performs strict equality comparison and requires the values to have the same type as well.

10 === "10"

returns false.

What is the difference between != and !==?

!= performs loose inequality comparison, while !== performs strict inequality comparison.

10 != "10";   // false
10 !== "10";  // true

What does > mean in JavaScript?

The > operator checks whether the left value is greater than the right value.

10 > 5

returns true.

What does < mean in JavaScript?

The < operator checks whether the left value is less than the right value.

5 < 10

returns true.

What does >= mean in JavaScript?

The >= operator checks whether the left value is greater than or equal to the right value.

10 >= 10

returns true.

What does <= mean in JavaScript?

The <= operator checks whether the left value is less than or equal to the right value.

10 <= 10

returns true.

Do comparison operators return Boolean values?

Yes. Comparison expressions return either true or false.

let result = 10 > 5;

console.log(result);

Output:

true

Which equality operator is commonly preferred in JavaScript?

When you want an exact equality comparison without type coercion, === is commonly preferred.

if (age === 18) {
    console.log("Age is exactly 18");
}

Can comparison operators compare strings?

Yes. JavaScript can compare strings for equality and relational relationships. String equality is case-sensitive.

console.log("JavaScript" === "JavaScript");

returns true, while:

console.log("JavaScript" === "javascript");

returns false.