Mac users have three reasonable options for PowerPoint-to-PDF. Which one is best depends on what you have installed and what you're trying to do.
PowerPoint for Mac
If you have PowerPoint installed: File > Save As > PDF. Same options as Windows PowerPoint. Best quality, fastest path, full feature support including handout layouts.
For people who already use PowerPoint daily, no need to look elsewhere.
Keynote as a substitute
Keynote opens PPTX files (File > Open > select .pptx). After import, File > Export To > PDF. Excellent quality output, but be aware: the PPTX-to-Keynote import may substitute fonts or shift some layouts.
For critical pixel-fidelity, use PowerPoint. For occasional conversion when you don't have Office, Keynote works well.
The browser route
Flint's PowerPoint to PDF in Safari handles PPTX directly. No app, no Office, no signup. Server-side conversion preserves fonts and layouts.
Good for one-offs, files you don't want to open in any local app, or when you're on a Mac without Office or Keynote installed (e.g. a borrowed machine).
macOS Print to PDF
From PowerPoint or Keynote: Cmd+P, then PDF dropdown > Save as PDF. Works but quality is slightly lower than the dedicated export options — fonts may not embed as completely. Use as a fallback when the proper Export to PDF isn't available.
FAQ
Which path is best quality?
PowerPoint for Mac's File > Save As PDF is the benchmark. Flint's online flow matches it.
Does Apple Silicon affect this?
No — all methods work on M-series Macs.
Can I batch convert?
Automator on Mac can batch-convert if PowerPoint is installed. For online, one file at a time on the free flow.
What if my PPTX uses Windows-only fonts?
Fonts substitute on macOS if not installed locally. Install the fonts on the Mac, or convert via Flint (server-side has broader font availability).
Three paths, comparable quality. Convert your PowerPoint to PDF in whichever fits your setup.