OPF vs other presentation formats
An honest comparison of OPF with PPTX, the Google Slides API, Marp, Slidev, and reveal.js — and when each one is the right choice.
At a glance
These tools solve different problems. PPTX is the universal exchange format for office software. Marp, Slidev, and reveal.js are excellent authoring tools for humans who write Markdown or HTML. OPF is an interchange format for software: structured JSON with a schema, built so programs and language models can produce, validate, and transform decks. The comparison below is about format properties, not tool quality.
| Format | Source | Git-diffable | LLM-authorable | Schema validation | Rendering |
|---|---|---|---|---|---|
| OPF | Plain JSON | Yes | Yes — fits structured output | Yes — JSON Schema | Any OPF-compatible renderer |
| PPTX (OOXML) | Zipped XML bundle | No — binary archive | No — too complex to emit reliably | OOXML schemas (very large) | PowerPoint and compatible apps |
| Google Slides API | API resources (JSON over REST) | No — lives in Google's cloud | Partially — via API calls, not documents | API types, not a document schema | Google Slides only |
| Marp | Markdown + directives | Yes | Mostly — loose structure, no validation | No | Marp CLI / VS Code to HTML, PDF, PPTX |
| Slidev | Markdown + Vue components | Yes | Mostly — loose structure, no validation | No | Built-in dev server and exporter |
| reveal.js | HTML (or Markdown) | Yes | Mostly — free-form HTML, no validation | No | Browser framework |
PPTX / OOXML
PPTX is the most compatible presentation format in existence, and the right output target when decks must open in PowerPoint. As a source format it is hard to work with: a .pptx file is a zip archive of interlinked XML parts, so version control sees opaque binary changes, code review is impossible, and LLMs cannot reliably emit it. A common pipeline is to author or generate decks as OPF JSON, validate them, and convert to PPTX at the end.
Google Slides API
The Slides API is a capable way to drive Google Slides programmatically, but the deck lives in Google's cloud rather than in your repository. There is no portable document you can check in, diff, or validate offline, and the API's request/response types are not a document schema. If your decks must live in Google Workspace, it is the right tool; if you want decks as reviewable source files, it isn't designed for that.
Marp & Slidev
Marp and Slidev are first-class tools for developers who writeslides. Markdown source is diffable and pleasant to author, and both render beautifully. The trade-off is structure: Markdown has no schema, so a generated deck can't be validated before rendering, and slide semantics (audience, narrative beats, layout intent, chart data) live in loosely defined front matter or comments. For human-authored talks they are a great choice; for machine pipelines the lack of a contract shows quickly.
reveal.js
reveal.js is a mature HTML presentation framework with a rich plugin ecosystem. Like the Markdown tools, the source is diffable, but it is presentation code rather than presentation data: content, styling, and behavior mix in free-form HTML. Generating it with an LLM works for simple decks but there is no way to validate the output, and extracting structured content back out is hard.
When to use OPF
OPF is the right choice when decks are produced or consumed by software:
- LLMs or agents generate decks via structured output and you need to validate before rendering.
- Decks live in git and changes go through code review like any other source file.
- You are building a renderer, converter, or analyzer and want a stable, open document contract.
- One source document must target multiple outputs (PPTX, HTML, images).
It is the wrong choice when a human just wants to write a talk — use Marp or Slidev — or when decks must be edited collaboratively in office software, where PPTX or Google Slides remain the destination. Start with the developer docs or the format spec.