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The conditional (ternary) operator is the only JavaScript operator that takes three operands. This operator is frequently used as a shortcut for the if statement.

Syntax

condition ? exprT : exprF 

Parameters

condition
An expression whose value is used as a condition.
exprT, exprF
Expressions with values of any type.

Description

If condition can be converted to true (it is truthy), the operator returns the value of exprT; otherwise (when condition is falsy) it returns the value of exprF.

(In either case, the other alternative expression is left unevaluated.)

Besides false, possible falsy expressions are: nullNaN0, the empty string (""), and undefined. If condition is any of these, the result of the conditional expression will be exprF.

A simple example:

var age = 26;
var beverage = (age >= 21) ? "Beer" : "Juice";
console.log(beverage); // "Beer"

One common usage is to handle a value that may be null:

function greeting(person) {
    var name = person ? person.name : "stranger";
    return "Howdy, " + name;
}

console.log(greeting({name: 'Alice'}));  // "Howdy, Alice"
console.log(greeting(null));             // "Howdy, stranger"​​​​​

Conditional chains

The ternary operator is right-associative, which means it can be "chained" in the following way, similar to an if … else if … else if … else chain:

function example(…) {
    return condition1 ? value1
         : condition2 ? value2
         : condition3 ? value3
         : value4;
}

// Equivalent to:

function example(…) {
    if (condition1) { return value1; }
    else if (condition2) { return value2; }
    else if (condition3) { return value3; }
    else { return value4; }
}

Specifications

Specification Status Comment
ECMAScript Latest Draft (ECMA-262)
The definition of 'Conditional Operator' in that specification.
Draft  
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'Conditional Operator' in that specification.
Standard  
ECMAScript 5.1 (ECMA-262)
The definition of 'The conditional operator' in that specification.
Standard  
ECMAScript 1st Edition (ECMA-262)
The definition of 'The conditional operator' in that specification.
Standard Initial definition. Implemented in JavaScript 1.0.

Browser compatibility

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
Basic supportChrome Full support YesEdge Full support YesFirefox Full support 1IE Full support YesOpera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes

Legend

Full support  
Full support

See also

Document Tags and Contributors

Last updated by: AdrianSkar,