Binary search (to find index of number in sorted array) - Javascript

function binarysearch(sorted,number) {
var start = 0
var end = sorted.length - 1
var mid
while(start <= end) {
mid = Math.floor((start+end)/2)
        if(sorted[mid] == number) {
        console.log("index is " + mid)
return mid
}
else if(number < sorted[mid]) {
end = mid-1
   }
else {
start = mid + 1
}
}
console.log("Not found")
}
var sorted = [1,2,3,4,5,6,7,8,9,10]
binarysearch(sorted, 3)
binarysearch(sorted, 90)