Compare the speed of two functions

compare.js

var iterations = 1000000;

console.time('Function 1');
for (let i = 0; i < iterations; i++ ){
    functionOne();
};
console.timeEnd('Function 1')

console.time('Function 2');
for (let i = 0; i < iterations; i++ ){
    functionTwo();
};
console.timeEnd('Function 2')