Error when length keyword is used to push lengths to an array.

I am trying to create an array called lengths which will have all the lengths of the elements in the array new_str.
The problem is when I am trying to push each length to the lengths array it says
‘Cannot read property ‘length’ of undefined’.
PS : My plan is to use Math.max() inorder to find the maximum length of the string in the array.

function findLongestWordLength(str) {
var new_str = str.trim().split(" ");
var lengths = [];
for(var i=0; i <= new_str.length; i++){
lengths.push(new_str[i].length);
}
console.log(lengths);
}

findLongestWordLength("The quick brown fox jumped over the lazy dog");