When working with generative AI tools like ChatGPT, Gemini, or Claude, the way you format your documents can significantly impact how well the AI understands your content. Whether you’re feeding it PDFs, PowerPoint slides, or text files, not all formats are created equal. Let’s explore the best document formats for AI — and why plain text often wins the AI game!
Why Document Format Matters for AI?
Generative AI models process text-based data at their core. While some advanced systems can read images or PDFs, these formats often introduce unnecessary complexity.
If your goal is to train a model, generate insights, or summarize information, the format you use can affect:
- How accurately the AI reads your data
- How much time it takes to process the file
- How “clean” and interpretable the input is
In short: the simpler, the better.
🥇 The Gold Standard: Plain Text (.txt)
Plain text is the most AI-friendly format available. It’s small, fast, and free from hidden code or binary data that can confuse a model.
Every computer since the 1980s can read .txt files, and so can every AI model. There’s no formatting fluff, no embedded images, and no compatibility issues — just pure, readable data.
When to use it:
- ✅ Converting documents for AI training or prompting
- ✅ Feeding long text content (like reports, essays, or transcripts) into an AI tool
- ✅ Creating structured datasets for analysis
🧾 PDFs: Readable, but Heavy
PDFs are widely used for sharing documents — and thankfully, modern AI models handle them quite well.
However, PDFs come with baggage:
- Larger file sizes
- Complex internal structures
- Occasional embedded code or formatting quirks
AI can read text-based PDFs without issues, but scanned or image-heavy PDFs are harder to interpret. In those cases, you’ll need an OCR (Optical Character Recognition) or visual language model to extract the text accurately.
Conversion Tip: Use tools like PDF to TXT to convert PDFs into plain text for cleaner AI processing!
🖼️ Slides and PowerPoints: Convert Before You Share
Slides and PowerPoint decks are great for presentations — but not for AI.
Most slides contain text fragments, images, and layout data, which don’t translate well when read by AI tools. If your slides are mostly text, convert them before uploading or prompting.
Best practice:
- Export slides to text or markdown
- Remove unnecessary visual elements
- Combine slide text into a cohesive document
🧩 Markdown (.md): The Sweet Spot for AI
Markdown is like plain text — but smarter. It uses simple syntax (like # for headers and * for lists) to structure content without adding complexity.
AI models love markdown because it provides clarity and context while remaining lightweight.
You can even export Google Docs to markdown directly: File → Download → Markdown (.md)
When to use it:
- ✅ Technical writing or structured documents
- ✅ Feeding formatted content (lists, headings, tables) into AI
- ✅ Creating readable prompts for AI workflows
In Summary
| Format | AI Compatibility | Best Use Case |
|---|---|---|
| Plain Text (.txt) | ⭐⭐⭐⭐⭐ | Clean data, prompt input |
| Markdown (.md) | ⭐⭐⭐⭐ | Structured text, formatting |
| PDF (.pdf) | ⭐⭐⭐ | General documents, reports |
| PowerPoint (.pptx) | ⭐⭐ | Convert to text first |
| Images (.jpg, .png) | ⭐ | Use visual AI models only |
⚙️ Keep It Simple
For the best AI results, simplify your content. Convert complex files and keep your formatting minimal.
If your computer needs extra software to open a file, AI will likely struggle too. Stick to formats that are open, simple, and transparent — like .txt or .md.