Font files aren't embedded in a PPTX: the file refers to a font by name, and the app on the computer that opens it does the drawing. So every font in your presentation takes one of three paths.
The font keeps its name
Montserrat, Roboto, Open Sans, PT Sans, Playfair Display, Lora and about twenty more fonts from the catalogue go into the file under their own name. The fonts themselves are not inside the file. If a font looks different, click “Enable Editing” in PowerPoint: cloud fonts don’t download in Protected View and usually load after it. Otherwise PowerPoint replaces the font, which changes the look and line breaks.
The font isn't in PowerPoint
Such a font is replaced in the file with a similar system font, so the text will look different:
| In the presentation | In the file |
|---|---|
| Inter, Manrope, Rubik, Golos Text | Arial |
| Unbounded, Russo One | Arial Black |
| Onest, Jost, Comfortaa | Century Gothic |
| Cormorant, Literata, Prata | Georgia |
| Caveat, Bad Script | Comic Sans MS |
| JetBrains Mono, PT Mono | Courier New |
Your own fonts and Google fonts
A font you uploaded to your account on Pro, or a Google font picked for a block, goes into the file under its own name. PowerPoint shows it only if it's installed on the computer; otherwise it substitutes a similar one.
How to check before downloading
On the presentation page, a “Fonts in the PPTX” line appears under the “Download” tiles. It lists the fonts that will be replaced or need installing. The “i” icon next to it shows what replaces what. The “i” next to the “Download” heading lists the fonts that keep their name.
If the exact look matters, pick a font in the editor that PowerPoint has, install the font on the computer you'll present from, or download a PDF: the browser prints it, so the fonts are the same as on the website.
PowerPoint 2019 and older, Keynote and LibreOffice may show fonts differently — open the file before you present.