## DEV Community # use `console.time()` and `console.timeEnd()` to measure the time taken to execute a piece of code, in JS

``````console.time('time')
console.log('Hello World')
console.timeEnd('time')
// Hello World
// time: 7.991ms
``````

Here in JavaScript we are having cool method called as `console.time` and `console.timeEnd` which is used to measure the time taken to execute a piece of code.

1. start with writing the code in `console.time('time')`, here are "time" is the name of the variable which we will use to store the time taken to execute the code
2. Start writing your complex code in `console.log('Hello World')`
3. Now I'll end the code with `console.timeEnd('time')` and we will get the time taken to execute the code

Note: `console.time` and `console.timeEnd()` must have same "string" name, which is `time` here.

It is really handy when you are learning Algorithums and you want to measure the time taken to execute the code.

# Let's try it out.

``````let nums = [];
// it's empty array.
for (let i = 0; i < 1000000; i++) {
// making a loop over 1 million times; and pushing it.
nums.push(Math.floor(Math.random() * 1000000));
}
// sorting the arrray
nums.sort(function (a, b) { return a - b });
``````

### Solving by Linear Search Algo:

``````let LinearSearch = function (nums, target) {
console.time("linear")
for (let i = 0; i < nums.length; i++) {
if (nums[i] === target) {
console.timeEnd("linear")
return i;
}
}
console.timeEnd("linear")
return -1;
}
// find million and 1
LinearSearch(nums, 1000001);
console.log(LinearSearch(nums, 1000001));
// linear: 10.044ms
// -1
``````

### Example with Binary Search Algo:

``````// Make a function of binary search
let nums = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
let target = 5;

let BinarySearch = function (nums, target) {
console.time("binary")
let start = 0;
let end = nums.length - 1;
while (start <= end) {
let mid = Math.floor((start + end) / 2);
if (nums[mid] === target) {
console.timeEnd("binary")
return mid;
}
else if (nums[mid] < target) {
start = mid + 1;
}
else {
end = mid - 1;
}
}
console.timeEnd("binary")
return -1;
}
console.log(BinarySearch(nums, 1000001))
// binary: 0.129ms
// -1
``````