Excel Floating Point Arihmetic - What Type Does It Actually Use

Question

From a previous questions someone indicated that Excel uses a 64 bit (8 byte) double-precision floating.

Is that correct - Is there any material on this at all?

I am trying to tie off numbers and this is killing me!

Answer 1

According to this article yes, it uses 64 bit double precision floating point numbers. The article also describes the rounding errors etc associated with this format.

Answer 2

Have a look at

Floating-point arithmetic

Under the section Precision

A floating-point number is stored in binary in three parts within a 65-bit range: the sign, the exponent, and the mantissa.

Here is another article

Understanding Floating Point Precision, aka “Why does Excel Give Me Seemingly Wrong Answers?”

Have a look at the section Structure of a Floating Point Number