Internal Precision of HP41 Series


Maybe this is common knowledge, maybe not. I think I once knew this a long time ago but I frankly can't remember.

Does anyone know how many digits the HP41CV (or CX) maintains internally during intermediate computations? I know that anything after 10-digits is lost to rounding once the result is placed on the stack, but I mean before that. I am advised that the HP42S carries 15-digits internally and rounds results to 12. Does the 41 series carry three extra digits too?

many thanks,



Yes, In the HP-41C and Voyager series, internal calculations use 13 mantissa digits.

I think this is also the case on the 91, 92, 67/97, 19C/29C, and Spice series.

On models before those (Classic series, 65, and Woodstock other than 29C), internal calculations only used 10 mantissa digits.

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