Is there any way to set column width exactly as Excel defines it?

I am editing spreadsheets in Libreoffice which I have to save in Excel format (.xlsx) and then send to someone (the boss). The person who receives them needs the column width to be exactly 25 for all but one column and 50 for the last one. For the column width Excel uses a formula that relates to character width (I am using 11pt Calibri font) and Libreoffice has no equivalent it seems.

Is there any way to set the column width as I need it without having a copy of Excel?

I don’t know what unit of measure you are using for “25” and “50” (you don’t say), but does

Format > Columns > Width not give you what you need?

For completeness: the description of Excel’s esoteric units is at

@BigRAI Libreoffice doesn’t offer the right units. I have added a link (which is also in the comments) that explains how Excel calculates it.

Sorry, I missed the link (old eyes).