today I'm thinking about the "don't use floating point for money" advice I hear all the time. It obviously has a lot of truth to it.

But -- Excel/Google Sheets uses floating point for all of its calculations, people use spreadsheets for money calculations all the time, and it generally seems to work just fine -- the results get rounded for display.

So I'm trying to figure out if there's a more nuanced guideline than "never use floating point for money".

The Dangers of using Float or Real Datatypes | Redgate

Floating point datatypes accommodate very big numbers but sacrifice precision. They are handy for some types of scientific calculations, but are dangerous when used more widely, because they can introduce big rounding errors.

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