Return Values

return sends a value back out of a function to whatever called it — a function without a return gives back undefined.

function add(a, b) {
    return a + b;
}

const result = add(2, 3);
console.log(result);

Expected output

5

Common mistakes

• Calling console.log() inside a function instead of returning the value — that only displays the result, it doesn't hand it back for the caller to store or use further.

Practice

Write a function square(n) that returns n * n, then log square(6).

function square(n) {
    return n * n;
}

console.log(square(6));