Why is 308.22 + 297.93 = 606.1500000000001 and not only 606.15?

Question

console.log(308.22 + 297.93);

In chrome console output is 606.1500000000001 but it should be 606.15. Why?

Long and exact response: http://docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html — Maxime Lorant, Dec 29 '13 at 21:57

score 2 · Accepted Answer · answered Dec 29 '13 at 21:57

2

Real numbers can not be represented in javascript (and other languages which use a floating-point type) accurately.

They are just an approximation. See floating point for more information.

answered Dec 29 '13 at 21:57

vsz

score 0 · Answer 2 · answered Dec 29 '13 at 21:57

0

It is down to how computers store floating point numbers.

That is why it is also tricky for comparisons.

answered Dec 29 '13 at 21:57

Ed Heal

2 Answers2