JavaScript query about ParseInt

Question

Could anyone explain why the result is 5?

console.log(parseInt('101', 2)); // 5

Because the second param is a radix, and the number 2 makes the parse interpret as binary number. More about that you can find here https://stackoverflow.com/questions/6611824/why-do-we-need-to-use-radix-parameter-when-calling-parseint https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt — Ion, Dec 11 '20 at 16:31

score 4 · Answer 1 · answered Dec 11 '20 at 14:32

4

The second argument to parseInt specifies the number base.

Base 2 is binary.

101 in binary is (1*4 + 0*2 + 1*1 =) 5 in decimal.

answered Dec 11 '20 at 14:32

Quentin

score 1 · Answer 2 · answered Dec 11 '20 at 14:42

1

The second argument you are passing to parseInt function is called Radix.

When you are passing 2 means that the string is in binary so the binary of 5 is 101.

5 (Decimal) = 101 (Binary)

That is why you are getting 5 as int.

answered Dec 11 '20 at 14:42

dev_mustafa

2 Answers2