Parameters and Arguments (JavaScript)

A parameter is defined by the function to specify what input is required to call the…

What is the difference between a parameter and an argument?

A parameter is defined by the function to specify what input is required to call the function.

function add(first, second) {
    return first + second;
}

An argument is a value that is passed into a function when calling the function

let costOfChocolate = 3.49;
let costOfMilk = 3.99;
// *costOfChocolate* and *costOfMilk* are arguments on line 4
let sum = add(costOfChocolate, costOfMilk);

Level: Apprentice · More JavaScript terms at this level

Updated September 19, 2026