JavaScript Loops and Iteration

Last updated: August 27, 2026.

JavaScript loops repeat a block of work. Choose the loop form that makes the stopping condition and the value being processed easy to understand.

Loop through array values with for…of

const products = ["Keyboard", "Mouse", "Monitor"];

for (const product of products) {
  console.log(product);
}

for...of is usually the clearest choice when you need each value from an array or another iterable.

Use a counter with for

const quantities = [2, 5, 3];
let total = 0;

for (let index = 0; index < quantities.length; index += 1) {
  total += quantities[index];
}

console.log(total);

A traditional for loop is useful when the index matters or when you need precise control over the counter.

Repeat while a condition is true

let attempts = 0;
let connected = false;

while (!connected && attempts < 3) {
  attempts += 1;
  connected = tryConnection(attempts);
}

function tryConnection(attempt) {
  return attempt === 3;
}

break and continue

for (const value of [4, -1, 7, 0, 9]) {
  if (value < 0) continue;
  if (value === 0) break;
  console.log(value);
}

continue skips the rest of the current iteration. break exits the nearest loop.

See MDN’s loops and iteration guide for every loop statement.