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---
title: If-Else Statement
---
## Introduction
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The `if` statement executes a statement if a specified condition is `true` . If the condition is `false` , then the statement inside `else` block gets executed.
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**Note:** The `else` statement is optional.
```javascript
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if (condition) {
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/* do this if condition is TRUE */
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} else {
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/* do this if condition is FALSE (or not TRUE) */
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}
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```
Multiple `if...else` statements can be chained to create an `else if` clause. This specifies a new condition to test and can be repeated to test multiple conditions, checking until a true statement is presented to execute.
```javascript
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if (condition1) {
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/* do something */
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} else if (condition2) {
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/* do something else */
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} else if (condition3) {
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/* do something else */
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} else {
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/* final statement */
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}
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```
**Note:** If you want to execute more than one statement in the `if` , `else` or `else if` part, curly braces are required around the statements:
```javascript
if (condition) {
/* do */
/* something */
/* with multiple statements */
} else {
/* do something */
/* else */
}
```
< a href = 'https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/if...else' target = '_blank' rel = 'nofollow' > MDN link< / a > | < a href = 'https://msdn.microsoft.com/en-us/library/85yyde5c.aspx' target = '_blank' rel = 'nofollow' > MSDN link< / a >
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### Additional ternary operator
For a simple operation like assigning a value to a variable conditionally you can use a ternary operator, which is a shorthand syntax for an `if...else` clause in JavaScript
```javascript
// Normal if...else
let num = 1;
if (someCondition){
num = 1;
} else {
num = 0;
}
// Using ternary operator
const num = someCondition ? 1 : 2;
// condition ? true case : false case
```
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## Examples
**Using** `if...else` :
```javascript
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// If x is equal to 5, then the condition is TRUE. This results in z being set to 7 and q being set to 42.
// If x does not equal to 5, then the condition is FALSE. This results in z being set to 19.
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if (x == 5) {
z = 7;
q = 42
} else {
z = 19;
}
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```
**Using** `else if` :
```javascript
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if (x < 10 ) {
return "Small number";
} else if (x < 50 ) {
return "Medium number";
} else if (x < 100 ) {
return "Large number";
} else {
flag = 1;
return "Invalid number";
}
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```
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**Using** `if` **alone** :
```javascript
// This function can also act as a Boolean
if (x < 30 ) {
return "true";
}