JS number function adds up zeros at the end [duplicate]

Question

I am using the Number() JS function which is supposed to convert string value to numeric.

It's working fine for small numbers. For big ones - it is starting to substitude values with zeros as shown on the image:

Is there a work around for this problem?

Answer 1

In JS, the largest integral value is 9007199254740991 That is, all the positive and negative integers should not exceed the -9007199254740991 and 9007199254740991 respectively.

The same is defined as the 2⁵³-1.

console.log(Number.isSafeInteger(parseInt('1111111111')))
console.log(parseInt('1111111111'))
console.log(Number.isSafeInteger(parseInt('111111111111111111')))
console.log(parseInt('111111111111111111'))
//9007199254740991 - The largest JS Number
console.log(Number.isSafeInteger(parseInt('9007199254740991')))

Answer 2

This is because you're using numbers that are larger than Number.MAX_SAFE_INTEGER and Javascript does not guarantee to represent these numbers correctly

Use Number.isSafeInteger to check:

> Number.isSafeInteger(Number('111111111111111111'))
< false