Why fonts and spacing change after PDF to Word conversion

Where the font went

A PDF can embed fonts, but it does not have to, and when it does the embed is often a subset: only the glyphs the document actually used. If a font is missing entirely, or licensed so the converter may not carry it over, Word has to pick a replacement. If only a subset arrived, any character you type that was not in the original falls back to something else, mid-word.

The tell is in the editor. Select the suspicious text and look at the font name. A font you have never installed is usually the substitute.

Why spacing drifts

Line breaks, justification, and vertical rhythm are all computed from letter widths. Change the widths and every line recomputes: paragraphs that fit on one line now wrap, pages that ended in the right place now run long, justified text develops rivers of space. None of the words changed. The arithmetic underneath them did.

Spacing rules can also be translated differently. A PDF stores the visual gap between lines; Word stores a spacing rule. When the rule is rebuilt from the visual gap, rounding moves everything a little, and the drift compounds over a long document.

What to check

Compare the first and last line of each page against the source — reflow shows up at page boundaries first. Check the font name on body text, on headings, and on anything that looks slightly wide or narrow. Look at justified paragraphs for stretched gaps. If the document is long, check the last page: drift accumulates forward.

How to fix it

Fix fonts at the style level, not by selecting lines. If you have the original font and the license allows it, install it and let Word re-resolve the text. If you do not, choose one deliberate substitute, set it in the styles, and accept the new line breaks — a document that is consistently one font is easier to work in than one with a substitute hiding every few paragraphs.

Resist nudging individual lines back into place. Hand-positioned fixes break again at the next edit. If the spacing drift is large, the underlying structure may be the real problem — check for text boxes before you fight the spacing.

Preventing the drift where you can

If you control the source, embed fonts fully when exporting the PDF instead of subsetting them, and prefer typefaces the people downstream actually have installed. If you receive PDFs regularly from the same tool, learn what that tool embeds — files from one exporter tend to substitute the same fonts in the same places, so the first file you diagnose teaches you the pattern for the rest.

Spacing fixes that survive the next edit

Most spacing complaints trace back to two settings: the spacing rules carried by styles, and the substitute font’s letter widths. Set line and paragraph spacing on the styles, never on selected lines, and change the font once at the style level. Then recheck. One of the two changes usually explains nearly all of the drift, and doing them one at a time tells you which.

What Papermeld does and does not promise

Papermeld converts the file in a conversation and notes what should be checked beside the output, fonts among them. It does not claim a pixel-perfect visual match, and it does not claim that every font survives the trip. You review the result against the source — the substitution arithmetic above is the reason that review exists.