How ChatGPT Is Really Used - and Why It Matters for GEO & Marketing

When ChatGPT launched in late 2022, no one expected that within three years it would reach 700 million weekly users - nearly 10% of the world’s adult population. By July 2025, users were sending over 2.5 billion prompts per day, making ChatGPT one of the fastest adopted consumer technologies in history.

But the real story isn’t just about scale. It’s about how people actually use ChatGPT—and what that means for brands, marketers, and the emerging field of Generative Engine Optimization (GEO).

What People Use ChatGPT For

The study shows three dominant categories that account for nearly 80% of all conversations:

• Practical Guidance – tutoring, how-to advice, creative ideation

• Seeking Information – facts, current events, product info (a direct substitute for Google search)

• Writing – emails, documents, summaries, translations

A key insight: Writing dominates work-related tasks (40% of work queries). But two-thirds of these aren’t creating new text—they’re about improving user-generated content (editing, critiquing, summarizing).

For marketers, this means: the way AI quotes and refines existing brand content is critical. If your content isn’t structured, data-rich, and authoritative, it won’t make it into the “improvement loop” that LLMs rely on.

Asking vs. Doing: Why Decision Support Wins

The research introduces a simple taxonomy:

• Asking (49% of queries) – people seeking guidance to make better decisions

• Doing (40%) – tasks where AI produces output (emails, code, plans)

• Expressing (11%) – casual talk, opinions, self-expression

Interestingly, Asking queries are growing faster than Doing—and are rated higher in quality.

Implication for GEO: Brands that provide clear, data-driven answers to decision-making questions (e.g. “What’s the best savings plan for families?”) will have outsized visibility in AI answers compared to those that only push polished marketing copy.

The Marketing Shift: From SEO to GEO

Three data points marketers can’t ignore:

1. Non-work usage is now 73% of ChatGPT queries – meaning AI influences everyday decisions from health to shopping.

2. Citations with numbers are 3x more likely to appear in AI answers.

3. Schema matters – structured data like FAQ and Dataset markup boosts visibility likelihood by ~40%.

This means GEO isn’t just about showing up—it’s about engineering trust signals (E-E-A-T) into content: experience, expertise, authority, and trustworthiness.

Actionable Steps for Marketers

• Think in Prompts, Not Just Keywords: What questions will users actually ask ChatGPT about your product or category? Build content around those prompts.

• Data = Visibility: Publish original stats, benchmarks, and case studies. AI engines reward numbers.

• Structure Everything: Use schema markup and clear formats (FAQs, tables, datasets) to make your content machine-friendly.

• Measure GEO Like SEO: Track your brand’s AI Visibility Score across engines (ChatGPT, Gemini, Perplexity) and iterate weekly.

Why This Matters for GEO’s Future

The research confirms what we at VIZI see every day: generative engines aren’t just search replacements - they’re decision engines. And in a world where billions of prompts are exchanged daily, brands that master GEO will shape the answers people trust.