Open a PowerPoint deck without PowerPoint

What it shows

• Every slide, in the order the deck shows them (the order in ppt/presentation.xml, not the slide file numbers, which drift when slides are moved). Each slide has its title, its text with bullet levels, its tables as real tables, and its pictures where they sit. On a phone a wide table scrolls sideways inside its own box.
• The speaker notes under each slide, as the presenter wrote them.
• Hidden slides, marked Hidden and listed at the top. PowerPoint skips a hidden slide in a slideshow, but the slide is still in the file for anyone who opens it, often with the backup numbers or an older draft.
• Video and audio clips embedded in the deck play here when the browser can play them (MP4, MOV with H.264, WebM, MP3, M4A, WAV). A clip that is only linked is listed with its address and never fetched.

What you can take out of it

• Every picture, video and audio file, one by one or all at once as a ZIP. Each is saved exactly as stored in the deck, usually at a higher resolution than the slide shows, and files used only on a layout, or left over from a deleted slide, are listed too.
• All the slide text and speaker notes as one plain-text file. Slide by slide: the title, the bullets indented by level, table rows with cells separated by |, and the notes after Notes:. It pastes cleanly into an e-mail, a document or a chat.
• The numbers behind each chart, as CSV. A PowerPoint chart keeps a copy of its data in ppt/charts/chartN.xml: the category labels and every series' values. viewhack reads that copy and saves it as a CSV that Excel, Numbers or Google Sheets open, so a bar chart becomes a table you can check or reuse.
• The fonts the deck uses, each marked as embedded in the deck or as one that must be installed on the computer that shows it. A missing font is replaced by a look-alike, which moves line breaks and can push text out of its box on the day of the talk.

What it cannot do

• The slide layout is not reproduced. Text, tables and pictures are shown one after another, not where they sit on the slide. Positions, sizes, colours, the theme and its background, and exact fonts are not drawn. Text boxes are read in the order they are stored, which is usually, but not always, the order you would read them.
• Animations and transitions are not played, and a slide's build steps are all shown at once. SmartArt and shapes are not drawn: a SmartArt diagram is marked in its place, with the text of its boxes listed in the order the deck stores them; the arrows, levels and layout that connect those boxes are lost. Charts are not drawn either; their data is shown as a table and saved as CSV.
• Password-protected decks cannot be opened. A .pptx with a password to open it is encrypted, and viewhack names it as a password-protected Office file. A password-protected .odp is detected from its manifest and reported as password-protected. A deck marked only as final, or protected against editing, is not encrypted and opens normally.
• PowerPoint 97–2003 .ppt files are not read yet. They are a binary compound file, a different format from .pptx, and viewhack names them without opening them. Open one in PowerPoint, LibreOffice Impress, Keynote or Google Slides and save it as .pptx, then drop that here.
• Bullet characters come from the slide master, which is not read. Text in a body placeholder is shown with a bullet unless the paragraph turns bullets off itself, so a master that removes bullets can make plain text look bulleted here.
• Macros never run. A .pptm's VBA project is not even read; the page says when a deck has one.
• The whole deck is read into memory. A deck of 100 MB of video works on a desktop; on a phone, a very large deck can take a while or make the browser close the tab.

Useful to know about .pptx and .odp files

A .pptx is a ZIP of XML files

Each slide is ppt/slides/slideN.xml, its notes ppt/notesSlides/notesSlideN.xml, and the pictures, clips and sounds sit in ppt/media/. Rename a copy to .zip and any unzip tool shows the parts. A .pptm is the same plus ppt/vbaProject.bin, which holds the macros; a .potx is a template.

An .odp works the same way

LibreOffice Impress keeps every slide in content.xml as a draw:page, with the notes inside it as presentation:notes, and pictures in Pictures/. A chart is a small document of its own (Object 1/content.xml) with its data in a table, which is what the CSV export reads.

A hidden slide is one attribute

In a .pptx, <p:sld show="0"> hides a slide; in an .odp, the page's style says presentation:visibility="hidden". Nothing else changes, so the slide keeps all its text, notes and pictures.

Chart data can outlive the spreadsheet

A chart pasted from Excel keeps the values it was last drawn from, even when the workbook it came from is gone. That cached copy is what PowerPoint redraws the chart from, and what is exported here. It may be older than the workbook if the link was never refreshed.

Embedded fonts

PowerPoint can embed fonts (File › Options › Save › Embed fonts in the file); they are listed in presentation.xml under embeddedFontLst and stored as ppt/fonts/fontN.fntdata. Some fonts forbid embedding in their licence, so PowerPoint leaves them out even with the option on.