Free online PPTX to MKV converter

Some televisions, media players, and video platforms accept MKV playback but cannot open PowerPoint presentations. Converting a PPTX creates a video version of the slides that can be played without presentation software.

What the PPTX format is

PPTX is the presentation format used by Microsoft PowerPoint and supported by programs such as LibreOffice Impress. It stores slides, text, images, charts, transitions, animations, and other presentation content in a package of XML files and media; it is commonly shared for editing or presenting.

What the MKV format is

MKV, or Matroska Video, is a container for video, audio, subtitles, and related tracks. It can hold streams encoded with different codecs, so compatibility depends on both the MKV container and the codecs used inside it. Choose MKV when the target player or archive workflow supports Matroska.

Online on 101convert.com

1. Upload the PPTX file on the converter page. Several files can be converted in one batch; check the page for its per-file size limit.
2. Before converting, set show each page for to the desired slide duration.
3. Start the conversion and download the resulting MKV file or files.

Offline with desktop software

LibreOffice Impress and OBS Studio are free programs available for Windows, macOS, and Linux. This method records the presentation as it plays rather than converting the PPTX package directly.

1. Open the PPTX in LibreOffice Impress and check that slides display correctly.
2. In OBS Studio, add a display or window capture source for the slideshow. Set the recording format to Matroska Video (.mkv) in Settings → Output → Recording.
3. Start the slideshow in Impress, start recording in OBS, and stop the recording after the final slide. Configure an audio capture source if the presentation’s narration or playback audio should be included.

Microsoft PowerPoint and FFmpeg provide another offline option on Windows. In PowerPoint, use File → Export → Create a Video and export the presentation as an MP4, selecting whether to use recorded timings and narrations. Then use FFmpeg to remux the MP4 into MKV without re-encoding: ffmpeg -i presentation.mp4 -c copy presentation.mkv.

Quality and compatibility

A recorded slideshow captures what appears during playback, while a PowerPoint video export can use the presentation’s recorded timings and narrations. The OBS method depends on real-time playback and capture settings; verify the finished video’s slide timing, audio, and resolution. Remuxing with -c copy preserves the MP4 streams without quality loss, but it does not change their codecs, so confirm that the target player supports them.