Conditional (ternary) operator

BaselineWidely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

Theconditional (ternary) operator is the only JavaScript operator that takes three operands:a condition followed by a question mark (?), then an expression to execute if the condition istruthy followed by a colon (:), and finally the expression to execute if the condition isfalsy.This operator is frequently used as an alternative to anif...else statement.

Try it

function getFee(isMember) {  return isMember ? "$2.00" : "$10.00";}console.log(getFee(true));// Expected output: "$2.00"console.log(getFee(false));// Expected output: "$10.00"console.log(getFee(null));// Expected output: "$10.00"

Syntax

condition ? exprIfTrue : exprIfFalse

Parameters

condition: An expression whose value is used as a condition.
exprIfTrue: An expression which is executed if thecondition evaluates to atruthy value (one which equals or can be converted totrue).
exprIfFalse: An expression which is executed if thecondition isfalsy (that is, has a value which can be converted tofalse).

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

Handling null values

One common usage is to handle a value that may benull:

const greeting = (person) => {  const 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 anif … else if … else if … else chain:

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

This is equivalent to the followingif...else chain.

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