JavaScript Comparison Operators
JavaScript comparison operators are essential tools for checking conditions and making decisions in your code.
1. Equality Operator (==)
The Equality operator is used to compare the equality of two operands.
// Illustration of (==) operator
let x = 5;
let y = '5';
// Checking of operands
console.log(x == 5);
console.log(y == 5);
console.log(x == y);
console.log();
// Check against special values
console.log(NaN == NaN);
console.log(0 == false);
console.log(0 == null);
Output
true true true false true false
2. Inequality Operator (!=)
The Inequality Operator is used to compare the inequality of two operands.
// Illustration of (!=) operator
let x = 5;
let y = '5';
// Checking of operands
console.log(x != 6);
console.log(y != '5');
console.log(x != y);
console.log();
// Check against special values
console.log(0 != false);
console.log(0 != null);
console.log(NaN != NaN);
Output
true false false false true true
3. Strict equality Operator (===)
The Strict equality Operator is used to compare the equality of two operands with type.
// Illustration of (===) operator
let x = 5;
let y = '5';
// Checking of operands
console.log(x === 6);
console.log(y === '5');
console.log(x === y);
console.log();
// Check against special values
console.log(NaN === NaN);
console.log(0 === false);
console.log(0 === null);
Output
false true false false false false
4. Strict inequality Operator (!==)
The Strict inequality Operator is used to compare the inequality of two operands with type.
// Illustration of (!==) operator
let x = 5;
let y = '5';
// Checking of operands
console.log(x !== 6);
console.log(y !== '5');
console.log(x !== y);
console.log();
// Check against null and boolean value
console.log(0 !== false);
console.log(0 !== null);
console.log(NaN !== NaN);
Output
true false true true true true
5. Greater than Operator (>)
The Greater than Operator is used to check whether the left-side value is greater than the right-side value.
// Illustration of (>) operator
let x = 5;
let y = "5";
// Checking of operands
console.log(x > 0);
console.log(y > "10");
console.log(x > "10");
console.log(y > 0);
Output
true true false true
6. Greater than or equal Operator (>=)
The Greater than or equal Operator is used to check whether the left side operand is greater than or equal to the right side operand.
// Illustration of (>=) operator
let x = 5;
let y = "5";
// Checking of operands
console.log(x >= 5);
console.log(y >= "15");
console.log(x >= "5");
console.log(y >= 15);
Output
true true true false
7. Less than Operator (<)
The Less than Operator is used to check whether the left-side value is less than the right-side value.
// Illustration of (<) operator
let x = 5;
let y = "5";
// Checking of operands
console.log(x < 15);
console.log(y < "0");
console.log(x < "0");
console.log(y < 15);
Output
true false false true
8. Less than or equal Operator (<=)
The Less than or equal Operator is used to check whether the left side operand value is less than or equal to the right side operand value.
// Illustration of (<=) operator
let val1 = 5;
let val2 = "5";
// Checking of operands
console.log(val1 <= 15);
console.log(val2 <= "0");
console.log(val1 <= "0");
console.log(val2 <= 15);
Output
true false false true
Comparison Operators List
There are many comparison operators as shown in the table with the description.
OPERATOR NAME | USAGE | OPERATION |
|---|---|---|
| Equality Operator | a == b | Compares the equality of two operators |
| Inequality Operator | a != b | Compares inequality of two operators |
| Strict Equality Operator | a === b | Compares both the value and type of the operand |
| Strict Inequality Operator | a !== b | Compares inequality with type |
| Greater than Operator | a > b | Checks if the left operator is greater than the right operator |
| Greater than or equal Operator | a >= b | Checks if the left operator is greater than or equal to the right operator |
| Less than Operator | a < b | Checks if the left operator is smaller than the right operator |
| Less than or equal Operator | a <= b | Checks if the left operator is smaller than or equal to the right operator |
Recommended Link
JavaScript Operators Complete Reference.
JavaScript Cheat Sheet-A Basic guide to JavaScript.
JavaScript Comparison Operators – FAQs
What is the difference between == and ===?
== compares values with type coercion, meaning it converts both values to a common type before comparing. === compares values without type coercion, ensuring both the value and type must match exactly.
When should I use == vs. ===?
Use === to avoid unexpected type coercion, ensuring both value and type are compared accurately. This makes your code more predictable and helps prevent potential bugs related to type conversion.
What is type coercion in JavaScript?
Type coercion is the automatic conversion of values to a common type during comparison. For example, in 5 == “5”, the string “5” is coerced to the number 5, resulting in true.
What are the differences between != and !==?
!= compares values with type coercion, converting both values to a common type before comparing. !== compares values without type coercion, ensuring both value and type differ, making it a stricter comparison.
How do the greater than and less than operators work?
> and < compare values directly to check if one is greater or less than the other, respectively. >= and <= compare values and also check for equality, ensuring one value is greater/less than or equal to the other.
What should I know about comparing different data types?
When comparing different data types, JavaScript may perform type coercion. To avoid unexpected results, use strict comparison operators (===, !==) and ensure the values being compared are of the same type before performing the comparison.
