What is the PPSX file format?
The .ppsx file extension is used with slide show files created with Microsoft PowerPoint or other similar software. A .ppsx file contains a collection of slides ready for presentation, and can also hold images, audio files, text, and other media.
.ppsx is rather unique in that it does not allow editing of its contents - only viewing is possible. This makes the format suitable for situations that require conducting a presentation without necessarily editing its contents. The counterpart that allows full editing is .pptx.
.ppsx combines an XML structure with ZIP compression. Benefits of this approach include reduced file size, improved data management, and a more reliable data recovery process. The format is an upgraded version of its predecessor, the .pps format - the added X in the extension name relates to the underlying XML structure, which offers a significant advantage: it allows programs other than the MS Office suite to open the file. .ppsx was introduced alongside PowerPoint 2007 as part of the Office Open XML standard.
When a .ppsx file is opened, it launches directly into full-screen slideshow mode. To edit the underlying slides, the file must be converted to .pptx first - for example, via PowerPoint's Save As function or an application such as LibreOffice Impress.
Security & safety
RISK: MEDIUMPPSX can embed macros only in its macro-enabled sibling .ppsm - a plain .ppsx cannot run VBA, so the format itself is low-risk. The practical danger is social-engineering: a slideshow that auto-plays may contain hyperlinks to phishing/malware sites, and attackers sometimes mail "invoice"/"photos" decks. Treat unexpected PPSX attachments with caution and don't click embedded links you weren't expecting. The rename-to-.pptx / unzip trick lets you inspect contents safely before viewing.
Format details
in a nutshellPrograms that open PPSX files
Windows3 apps
Microsoft PowerPoint
Paid Double-click to play; press Esc then open in PowerPoint to edit, or Save As .pptx. 
WPS Presentation (Kingsoft)
Freemium Opens and edits PPSX; free tier covers viewing and basic editing. 
macOS3 apps
Apple Keynote
Free Open the .ppsx; Keynote imports it (some formatting may shift), then edit/export. 
Linux1 app
LibreOffice Impress
Open-source The standard way to open/edit PPSX on Linux; exports to PDF/PPTX/ODP. 
Android1 app
Microsoft PowerPoint (mobile)
Free Open the PPSX to view; sign in with a Microsoft account for editing.
Microsoft PowerPoint (mobile)
Free Tap the PPSX in Files or Mail to view; edit with a Microsoft account. 
Technical details
deep spec| MIME type | application/vnd.openxmlformats-officedocument.presentationml.slideshow |
| Container | ZIP archive - each logical component (slides, media, themes) stored as a separate file inside the package |
| Magic bytes | 50 4B 03 04 (PK ZIP signature); distinguished from .pptx by [Content_Types].xml declaring the slideshow content type |
| Opens in | Full-screen slideshow mode by default; cannot be opened for editing without converting to .pptx |
| Editable counterpart | .pptx - shares the same internal XML structure; slideshow vs. edit mode is controlled by a flag in the package manifest |
| Macro support | None - macro-enabled presentations use the .ppsm extension instead |
| Predecessor format | .pps - the older binary PowerPoint Show format, superseded by .ppsx in PowerPoint 2007 |
| XML schemas used | DrawingML (dml) and PresentationML (pml) namespaces define slide content, layouts, animations, and transitions |
| Font embedding | Optional; embedded fonts stored as binary font parts inside the ZIP package |
| Media storage | Images, audio, and video stored as discrete files within the /ppt/media/ folder of the package |
| Encryption | Supports password-based AES-256 encryption via the OOXML EncryptionInfo structure |
| Animations & transitions | Stored in individual slide XML files as timing and transition elements; fully preserved on open |
| Cross-application support | Readable by LibreOffice Impress, Apple Keynote, Google Slides, and WPS Presentation without conversion |
| Compression | Individual XML parts compressed with DEFLATE; binary parts such as images may be stored uncompressed |
| Released | 2007 (Office 2007, Office Open XML) |
| Open standard | Yes · royalty-free |
| Specification | learn.microsoft.com |
PPSX conversions
Community Q&A
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