Open the PDF's document properties and look at the fonts tab. Every font should say embedded or embedded subset. Anything that does not will be substituted on machines that lack it.
The fix is at creation time: enable font embedding and export again. A finished PDF missing its fonts cannot be fully repaired, because the font data was never written into it.
You send a document that looks exactly right. The recipient opens it and the headings are in a different typeface, the line breaks have moved, and the two page document is now three. Nothing was corrupted in transit. Their computer simply drew the text with what it had.
Why substitution changes the layout
Every typeface has its own metrics: the precise width of each character, how much space sits between pairs of letters, how tall the lowercase letters are relative to the capitals.
Search for this and the usual phrase is pdf missing fonts, which names the cause exactly. Nothing is lost from the document. What is missing is the instruction to carry the typeface along with it, so the reader at the other end substitutes whatever it has.
When a font is missing, the reader picks something it does have and draws the text with that instead. The words are correct and every measurement behind them is different. Lines that fitted now wrap, paragraphs grow, and everything below moves down the page. A heading that sat comfortably at the top of page two ends up alone at the bottom of page one.
Embedded font data so no machine has to substitute anything.
Different character widths mean different line breaks and different pagination.
Font data has to be written when the PDF is made. It cannot be added convincingly later.
Checking whether fonts embedded
This is the single most useful thing to know. Desktop readers such as Adobe Acrobat Reader list it in document properties; the viewers built into browsers generally do not, so check in a desktop reader.
Open document properties
In Adobe Acrobat Reader it is File, then Properties. Other desktop readers keep it under a similar name in the File menu.
Find the fonts tab
It lists every font the document uses, with its type and its embedding status beside it.
Read the status for each entry
Embedded or Embedded Subset is what you want. A font listed with neither will be substituted anywhere it is not installed.
Why a font sometimes cannot embed
Usually a setting was off. Occasionally the font itself forbids it.
Font files carry licensing flags describing what is permitted, and some commercial fonts are marked as not embeddable. Software honours that and substitutes at export time, sometimes without saying anything. The result is a PDF that never contained the font you designed with, produced from a document that looked correct on the machine that made it.
- Embedding option was offTurn it on, re-export
- Font licence forbids itUse a different typeface
- Printed instead of exportedExport properly
- Standard fonts assumed presentEmbed them anyway
- Font substituted before exportFix in the source document
Fixing it
The reliable route is to go back to the source document and export again with embedding enabled. Word, Pages, Google Docs, InDesign and every serious design tool offer the option, usually in save or export settings.
If the source is gone and only the PDF remains, the options are worse. Converting the text to outlines makes the shapes permanent at the cost of all searchability and accessibility. Rasterising the pages does the same more bluntly and inflates the file. Both are salvage operations rather than fixes, and both should be a long way down the list behind finding the original.
If the original is a Word file and you have no copy of Word, PDFslime's Word to PDF converter embeds a font too, but it sets the text in Noto Sans rather than your document's typeface. That cures the substitution and not the look. Where the embedding setting lives in Word itself is covered in converting Word to PDF.
The proper repair
- Enable embedding and export again
- Text stays selectable and searchable
- Accessibility structure is preserved
- File size barely changes
- Needs the original document
When the source is gone
- Outlining text freezes the shapes
- Searchability and accessibility are lost
- Rasterising works and inflates the file
- Neither can be undone afterwards
- Last resort, not a first choice
Avoiding it in the first place
This is one of the easier PDF problems to design out, because the decisions all happen before the file is created.
Export rather than print. Both routes usually embed fonts, but only export keeps links, structure and tags.
Turn on font embedding once in the application's save options. It then applies to everything you export afterwards.
Before sending anything important, open document properties and read the fonts tab. It tells you whether the layout will survive the trip.
Convert a Word file with its font embedded
Word to PDF embeds its font in the file, so nothing is substituted. The text is set in Noto Sans rather than your original typeface.
Common questions
Checking and fixing embedding.
01Why do my fonts change on someone else's computer?
Because they were not embedded in the PDF, so the recipient's reader substituted whatever it had. Different fonts have different character widths, which is why the layout shifts as well as the appearance.
02How do I check whether fonts are embedded?
Open the PDF's document properties and look at the fonts tab. Each font should be listed as Embedded or Embedded Subset. Anything without that marking will be substituted on machines that do not have it installed.
03What does embedded subset mean?
Only the characters the document uses were included, rather than the entire typeface. This is normal and keeps the file small. It only matters if someone later edits the text and needs a character that was not included.
04Why did a font refuse to embed?
Usually the embedding option was switched off. Sometimes the font's licence explicitly forbids embedding, and software honours that flag by substituting at export time, occasionally without warning you.
05Can I embed fonts into a PDF that is already finished?
Not convincingly. The font data was never written into the file, and although some tools claim to add it, the pages were already laid out using substituted metrics. Re-exporting from the original document is the only proper fix.
06Does Print to PDF embed fonts?
Usually it embeds something, because the printer needs glyph shapes to draw with. What it does not preserve is the document structure, links and tagging. Exporting is better on every count where the application offers it.