how to add up numbers in an array code example

Example 1: sum all elements in array javascript

arr.reduce((a, b) => a + b)

Example 2: js array sum

console.log(
  [1, 2, 3, 4].reduce((a, b) => a + b, 0)
)
console.log(
  [].reduce((a, b) => a + b, 0)
)