TL;DR
The best formats for feeding web data to an AI are markdown and plain text for reading tasks, and JSON for structured fields. Markdown keeps headings and lists that help an LLM understand structure while staying token-efficient; JSON is ideal when you need typed fields. Raw HTML is the worst choice: it wastes tokens on markup the model does not need.
Match the Format to the Task
There is no single best format; there is a best format per use.
Markdown, for reading and RAG. When the AI needs to read and reason over page content (summarization, question answering, RAG), markdown is the sweet spot. It preserves the structure that carries meaning (headings, lists, links, emphasis) while stripping the tags, scripts, and styles that carry none. See markdown conversion.
JSON, for structured fields. When you want specific values (price, SKU, author, date), give the model, or receive from it, JSON. It is unambiguous, typed, and drops straight into a database or pipeline without further parsing. See structured data.
Plain text, for simple bulk content. When structure does not matter and you just need the words (sentiment, keyword analysis), stripped plain text is the most token-efficient of all.
Why Not Raw HTML
Feeding raw HTML to an LLM is the common mistake. A typical page is mostly markup: nav, scripts, inline styles, tracking, and deeply nested divs. That noise inflates token count (and cost), buries the actual content, and can confuse the model. The same page as markdown is often a fraction of the tokens and far clearer.
Raw HTML: ~8,000 tokens, most of it tags and boilerplate
Markdown: ~1,200 tokens, just the readable contentA Practical Rule
If a human would read it, feed markdown. If a database will store it, feed or request JSON. Never feed raw HTML unless the task is specifically about the markup itself.
Key Takeaways
- Markdown for reading and RAG, JSON for structured fields, plain text for bulk content.
- Raw HTML wastes tokens and buries content; avoid it as model input.
- Choose by task: readable content vs typed fields vs plain words.
How ScrapeGraphAI Handles This
ScrapeGraphAI returns AI-ready formats directly: scrape produces clean markdown, and extract produces structured JSON against your schema, so you feed the model the right format without converting raw HTML yourself.