Converting a spreadsheet to PDF produces a fixed, paginated document that looks identical everywhere — useful for circulating figures that should be read rather than edited, and for attaching to anything that expects a document instead of a workbook. The conversion runs on our server, because laying out a spreadsheet for print requires a document engine: the file is streamed through and the PDF streamed back, with nothing stored, though the file does leave your device. The thing to understand before converting is that a spreadsheet has no natural page size. A wide sheet has to be broken across pages somewhere, and where that break falls is decided by the print settings inside the workbook rather than by the conversion. Setting the print area, orientation and scaling in Excel first is what separates a clean result from forty pages of stray columns.
Set the print area before converting
The single most common bad outcome is a document far longer than expected, with columns spilling onto pages of their own. It happens because the sheet is wider than a page and nothing told the layout engine what to do about it.
Fix it in the spreadsheet, where the controls are: define the print area so stray cells outside the data are excluded, choose landscape for wide tables, and use fit-to-width scaling so the columns are compressed onto one page rather than split. The conversion honours those settings.
Repeat the headers
A table running over several pages is unreadable from page two onward if the column headings only appear on page one. Excel's print titles setting repeats chosen rows at the top of every page, and it carries through into the PDF.
The same applies to the first column on very wide tables. Between repeated headers and sensible page breaks, a long table becomes a document someone can actually read rather than a stack of anonymous numbers.
What does not come across
Everything interactive is lost by design, which is usually the point: formulas become their computed values, filters and slicers disappear, and nothing recalculates. Anyone who needs to work with the data needs the workbook, not the PDF.
Hidden rows and columns stay hidden, which is worth verifying rather than assuming — a hidden column with a working formula still influences the values you are publishing. Charts and conditional formatting render as they appear on screen.