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Presentation Video Maker

Turn PowerPoint (PPTX) slides into narrated MP4 videos locally using speaker notes, recordings, or local audio files.

View on GitHub
Local processing
About your filesFiles and content selected in this tool are processed in your browser and are not uploaded to a Browser Kitty backend.
Operation demo See the basic workflow in a short video.

About this tool

Presentation Video Maker reads PowerPoint (PPTX) files in the browser and turns slides into narrated MP4 scenes. Speaker notes can become narration scripts, while slide text can provide a draft when notes are missing. PPTX files, speaker notes, audio assets, and generated videos are not uploaded to Browser Kitty.

On desktop, scenes can use device speech, your own microphone recording, or local audio files. On smartphones, microphone recordings or local audio can be used from PPTX import through MP4 export. Work can be saved as a local .pvm project, with 720p / 1080p output, subtitles, BGM, and fade options available.

Good for

  • Create narrated training, lecture, or instruction videos from PowerPoint speaker notes
  • Attach your own recordings or local audio to individual slides and export one MP4
  • Turn a presentation into video without uploading the deck or recordings to an external video service
  • Save a long editing session and resume later to revise narration or subtitles

What it can do

Key capabilities available in this tool.

How to use

  1. Open the tool and choose a PowerPoint (.pptx) file, or open a saved .pvm project to continue earlier work.
  2. Review the slide previews and narration scripts imported from speaker notes.
  3. Choose device speech, your own recording, or a local audio file for each scene and complete the needed narration. On mobile, use your own recording or local audio.
  4. Adjust scripts, lead-in / lead-out padding, and included scenes, and save a .pvm project when you want a resume point.
  5. Choose 720p / 1080p, cut / fade, subtitles, BGM, volume, and looping options.
  6. Create the video and preview the generated MP4.
  7. Save the MP4 with your chosen file name, and optionally export the script as TXT or subtitles as SRT / VTT.

Supported

  • Input: PPTX files (current UI limit 150 MB) and .pvm projects for resuming work. Narration can use microphone recordings or local audio files.
  • Narration modes: device speech / your own recording / local audio on desktop; your own recording / local audio on smartphones.
  • Output: H.264/AAC MP4 at 720p or 1080p with cut / fade, burned-in subtitles, and local BGM. TXT, SRT, and VTT can also be saved.
  • Video generation: supported environments use an accelerated WebCodecs path, with a MediaRecorder + FFmpeg WASM fallback when needed.
  • Projects: .pvm stores the source PPTX, scripts, recordings, BGM, and output settings for resuming later; generated MP4 files are not duplicated into the project.
  • Runtime networking: required runtimes are embedded in the standalone HTML, with connect-src 'none', no runtime CDN, analytics, telemetry, or cloud TTS API.

Limitations and notes

  • This is not PowerPoint itself, so complex layouts, fonts, shapes, or effects can render differently from the original PPTX.
  • Smartphones cannot capture device TTS output as narration material; use a microphone recording or local audio file instead.
  • 1080p and long decks can use substantial device memory, so 720p is recommended especially on smartphones.
  • Capturing device speech on desktop depends on the browser and operating system's screen-sharing and system-audio capture capabilities.
  • Export speed and the available accelerated path depend on WebCodecs support, codecs, browser behavior, and device performance.

Frequently asked questions

Are PPTX files or recordings uploaded to a server?

No. PPTX parsing, speaker-note extraction, script editing, audio processing, and video creation run in the browser, and selected files are not uploaded to Browser Kitty.

Can I create the video using only a smartphone?

Yes. You can import a PPTX, edit scripts, use microphone recordings or local audio, configure subtitles and BGM, and save the MP4. Device TTS capture is not available on smartphones.

Can speaker notes be used as narration scripts?

Yes. Speaker notes are imported as the script when present. If a slide has no notes, slide text can be used as a draft.

Can I save unfinished work and continue later?

Yes. A local .pvm project stores the source PPTX, scripts, recordings, BGM, and output settings so work can be resumed later. Generated MP4 files are not duplicated into the project.

Offline version and source code

Save the standalone HTML build to parse PPTX files, edit scripts, record or attach audio, save projects, configure subtitles/BGM, and generate MP4 without runtime external connections. Recording and screen-sharing features still depend on browser and OS permissions.

View source on GitHub

Use together

Useful next steps and companion tools, organized around the workflow.

Compress the finished video Video Compressor If the generated MP4 is still too large, reduce resolution or bitrate with Video Compressor. Inspect the finished video Media Inspector Inspect codec, resolution, duration, bitrate, and other details of the generated MP4.