Convert ODP to PPTX

This is not a filing decision. Somewhere there is a laptop wired into a projector, running whichever build of PowerPoint the venue installed, with whichever fonts came with it, and you will meet it about four minutes before you speak. Everything on this page follows from that.

The value of converting in advance is that it moves the risky step to a time when you can do something about it. A deck translated here can be opened, scrolled through and fixed this evening. The same translation performed by an unfamiliar program on unfamiliar hardware, in front of an audience, offers no such option. Everything that follows is therefore a checklist rather than a comparison of formats. What survives the conversion matters far less than what you can verify before you leave the house.

Recent versions of PowerPoint do read OpenDocument presentations, so in principle you could hand over the .odp and hope. Sometimes that works perfectly well, and if the room is friendly and the laptop is yours, it is a reasonable thing to do.

It stops being reasonable when any part of the chain is out of your hands. Upload forms validate extensions. AV technicians copy files onto a machine an hour before the session and will not debug an import. Corporate builds disable format support you assume is there. Converting first removes an entire category of thing that can go wrong at the worst possible moment. It also removes an argument. A technician handed a file extension they do not recognise, ten minutes before a session, will say no rather than experiment, and they are right to. A .pptx is not a discussion.

A deck names the typefaces it wants and does not contain them. On slides that is unforgiving: text is sized to fit its box, so a substitute with slightly different metrics pushes a title onto a second line and over whatever sits below it. Body text reflows, bullet lists grow, and a slide that was balanced is no longer balanced.

The conversion machine here carries metric-compatible replacements for Arial, Times New Roman, Courier New, Calibri and Cambria, so decks in those faces keep their spacing through the conversion. The venue machine is a separate problem entirely. If the design depends on something distinctive, either accept that it will be substituted or convert the affected headings to shapes before the talk. A quicker test than reasoning about it: open the converted deck on a machine that does not have your fonts installed — a colleague’s laptop, a spare account — and look at the title slides. Two minutes there tells you more than any list of which fonts are common.

The deck keeps its own proportions through the conversion; what changes is the display it eventually meets. A 4:3 deck on a widescreen projector gains bars down both sides, and a 16:9 deck on an older 4:3 system gains them top and bottom, with everything scaled down to fit.

Neither is a fault and both are worth knowing in advance, because the surprise is what costs you the first minute of the talk. If the venue has published what its projectors are, match it. If it has not, 16:9 is the safer default and a slide whose content sits well inside its margins survives either outcome. The thing to avoid is content that depends on the edges: a footer with the date in it, a logo in a corner, a diagram that fills the frame. Those are the first casualties when a projector scales a deck to fit.

The straightforward effects convert well — appear, fade, wipe, and the standard slide transitions. Both programs have them and they mean the same thing in each. What travels less predictably are motion paths, effects chained to triggers, and sequences timed against a media clip, because the two animation models diverge as soon as the timing becomes precise.

A static slide gives you no evidence either way, so run the deck through once after converting rather than clicking along the thumbnails. That rehearsal is the only thing that distinguishes an animation that survived from one that quietly did not, and it takes as long as the talk does. If a build has not come through, the fastest repair is to delete the effect rather than reconstruct it. A slide that shows everything at once is a slide you can talk over; a slide that advances unpredictably is one that talks over you.

Media is the least reliable part of any deck handover, and it fails for reasons that have nothing to do with the conversion. The clip has to be present, the venue machine has to hold a codec for it, and the audio has to reach a sound system somebody remembered to unmute.

Carry the media files separately on the same drive as the deck, know which slide each belongs to, and have an answer for the room if a clip refuses to play. A presenter who says what the video showed and moves on has lost fifteen seconds. A presenter who spends four minutes fighting a dialogue box has lost the room.

Notes are held per slide in both formats and come across attached to the slides they belong to, so presenter view on the venue machine shows them as expected. For anyone who scripts a talk rather than improvising it, this is the part of the conversion worth confirming first.

Open two or three slides in the converted file and check that the notes are the current ones rather than an earlier draft. It is also worth remembering that the notes travel inside the file you hand over: if a session is being recorded or the deck will be distributed afterwards, whatever you wrote to yourself goes with it. Notes written in the small hours have a way of being candid about a competitor, a colleague or the audience, and the deck that gets circulated to attendees is the same file you presented from unless somebody deliberately strips them first.

Convert to PDF alongside the PPTX and put both on the drive. A PDF opens on any machine in the building including a phone, needs no office suite, cannot reflow, cannot substitute a font, and will not ask about enabling anything. It is the cheapest insurance available for a talk.

It will not animate and it will not play video, which is exactly the trade you want at that moment: a deck that is definitely readable beats a deck that is ideally interactive. Present from the PPTX, and know the PDF is one folder away if the room turns out to be hostile. Put both files and any video clips in one folder named after the talk, on a drive that is not encrypted with software the venue will not have. The number of presentations delayed by a locked USB stick is not small.

Converting between two presentation formats requires a presentation program, so this runs on a server rather than in your browser. The deck goes over an encrypted connection to a container running LibreOffice headless and nothing else, which is stated here rather than left to assumption.

The container has no outbound internet route. Each job gets its own scratch directory and its own profile, and the directory is deleted the moment the job ends, whatever the outcome; anything still running after sixty seconds is stopped. The free ceiling is 25 MB per file — decks reach it through embedded video and photographs, so a media-heavy talk may need its clips carried separately in any case.

If the deck is being submitted to be read — a conference wanting slides for its proceedings, a committee circulating papers, a colleague catching up on a session they missed — a PowerPoint file is more than they need and gives them the ability to edit your work.

Send a PDF in that case and keep the ODP as your master. Convert to PPTX for the specific situation this page is about: a person standing in a room, driving your slides from software that is not yours, on a machine you did not choose.