# Does the specific ChatGPT model version a customer is using change whether we show up, and should that affect our playbook?

Reviewed by Martin Dejnicki, Director of SEO & AI Search · facts verified October 9, 2026 · canonical: https://deploi.ca/shopify/faq/chatgpt-model-version-visibility-impact

## Short answer

Yes: ChatGPT now gives shoppers different models by plan, so two shoppers asking the same question can see different brands. OpenAI's GPT-6 is rolling out as the default for eligible Plus, Pro, Business and Enterprise users, while Free and Go users get GPT-5.6 Luna ([OpenAI Help Center](https://help.openai.com/en/articles/20001354-gpt-6-and-other-models-in-chatgpt), October 2026). The version should change how you measure, not what you publish.

- **Default model, Plus to Enterprise:** GPT-6, rolling out. Rolling out as the default in ChatGPT for eligible Pro, Plus, Enterprise and Business users (OpenAI Help Center, October 2026). ([OpenAI Help Center, GPT-6 and other models in ChatGPT](https://help.openai.com/en/articles/20001354-gpt-6-and-other-models-in-chatgpt))
- **Default model, Free and Go plans:** GPT-5.6 Luna. Becoming the default for Free and Go users, who do not get GPT-5.6 Sol; logged-out users do not get GPT-5.6 Sol either (OpenAI Help Center, October 2026). ([OpenAI Help Center, GPT-6 and other models in ChatGPT](https://help.openai.com/en/articles/20001354-gpt-6-and-other-models-in-chatgpt))
- **Same brand list twice:** Under a 1 in 100 chance. ChatGPT and Google's AI, asked the same prompt 100 times; the same order came closer to 1 in 1,000 (SparkToro with Gumshoe.ai, 2,961 runs of 12 prompts, January 2026). ([SparkToro, NEW Research: AIs are highly inconsistent when recommending brands or products](https://sparktoro.com/blog/new-research-ais-are-highly-inconsistent-when-recommending-brands-or-products-marketers-should-take-care-when-tracking-ai-visibility/))
- **Web search in ChatGPT:** Runs when the question needs it. ChatGPT may search the web automatically when a question would benefit from current information, so some answers cite sources and some do not (OpenAI Help Center, October 2026). ([OpenAI Help Center, Searching the web with ChatGPT](https://help.openai.com/en/articles/9237897-searching-the-web-with-chatgpt))

## Deploi's call

The model version changes what a shopper sees, so it belongs in your measurement, not your content plan. Track the version or do not track. An AI-visibility number without a model, a date and a sample size is a screenshot with ambition.

**CUSTOMIZE: Make your visibility measurement version-aware when**

- You report AI visibility to leadership. Run a prompt panel, a fixed set of shopper questions asked on a schedule, and log the plan, model, date and cited sources for every run. Deploi's [AI answer engine visibility record](https://deploi.ca/shopify/build-vs-buy/ai-answer-engine-visibility-geo-aeo) builds model-version notes into that panel (October 2026).
- One screenshot is driving a decision. ChatGPT had under a 1 in 100 chance of repeating a brand list in [SparkToro's study](https://sparktoro.com/blog/new-research-ais-are-highly-inconsistent-when-recommending-brands-or-products-marketers-should-take-care-when-tracking-ai-visibility/) (January 2026), so report a visibility percentage.
- Your shoppers use free accounts. Free and Go users get GPT-5.6 Luna rather than GPT-6 ([OpenAI Help Center](https://help.openai.com/en/articles/20001354-gpt-6-and-other-models-in-chatgpt), October 2026), so run the panel on a free account too.

**WAIT: Leave your content alone while**

- OpenAI's list of what ChatGPT weighs for products names no model-specific rule ([OpenAI Help Center](https://help.openai.com/en/articles/11128490-shopping-with-chatgpt-search), October 2026), so no model has its own content playbook.
- A visibility swing lines up with a model change in [OpenAI's release notes](https://help.openai.com/en/articles/9624314-model-release-notes), such as GPT-5.6 Sol's arrival in July 2026.

## Which ChatGPT model answers a shopper today?

The ChatGPT model that answers a shopper depends on the shopper's plan, which means two shoppers can meet two different models. OpenAI's model guide sets a default for each plan and says when ChatGPT switches models by itself ([OpenAI Help Center](https://help.openai.com/en/articles/20001354-gpt-6-and-other-models-in-chatgpt), October 2026).

**ChatGPT's default model differs by plan, and Business and Enterprise workspaces can add thinking automatically**

| Shopper's plan | Default model | When ChatGPT switches models by itself |
| --- | --- | --- |
| Free and Go | GPT-5.6 Luna, rolling out | Not stated for these plans |
| Plus and Pro | GPT-6, rolling out; the user picks a thinking level | For safety, after a usage limit on its thinking levels, or after the GPT-6 Pro weekly limit on Pro $200 |
| Business and Enterprise | GPT-6, rolling out; admins may limit which models members can use | When workspace settings allow it, such as the Higher intelligence setting on Business |
| Logged out | Not stated; no GPT-5.6 Sol | Not stated |

Sources: [OpenAI Help Center, GPT-6 and other models in ChatGPT](https://help.openai.com/en/articles/20001354-gpt-6-and-other-models-in-chatgpt). Verified October 9, 2026.

On Plus and Pro, Instant, OpenAI's setting for fast everyday answers, "doesn't automatically switch to a higher thinking level for complex requests". So the plan, the model menu and, on Business and Enterprise, a workspace setting decide the model. None of that changes the case for [one product page that serves every AI engine](https://deploi.ca/shopify/faq/product-page-structure-chatgpt-vs-perplexity-vs-gemini).

## What else changes ChatGPT's answer besides the model?

Three other things change ChatGPT's answer besides the model, and OpenAI or a named study documents each one:

1. **Whether ChatGPT searches.** ChatGPT "may search the web automatically when your question would benefit from current information" ([OpenAI Help Center](https://help.openai.com/en/articles/9237897-searching-the-web-with-chatgpt), October 2026). An answer that searched cites sources; in our reading, one that did not can name brands from training data alone.
1. **The shopper's context.** For product results, ChatGPT "considers your query and context (such as Memory or Custom instructions)" ([OpenAI Help Center](https://help.openai.com/en/articles/11128490-shopping-with-chatgpt-search), October 2026), and none of that context is visible to you.
1. **Chance.** A study ran 12 prompts 2,961 times across ChatGPT, Claude and Google's AI ([SparkToro](https://sparktoro.com/blog/new-research-ais-are-highly-inconsistent-when-recommending-brands-or-products-marketers-should-take-care-when-tracking-ai-visibility/), January 2026). ChatGPT and Google's AI had under a 1 in 100 chance of giving the same brand list twice in 100 runs. The chance of the same order was closer to 1 in 1,000. SparkToro ran it with Gumshoe.ai, which sells AI tracking tools.

So the model is one of four moving parts, which is why a single run cannot tell you whether your brand shows up.

## What should a ChatGPT visibility panel log?

A ChatGPT visibility panel should log the prompt, the plan tier, the model, the date, whether the answer searched the web and which sources it cited, for every run, because an unlogged answer cannot be repeated. The minimum:

- A fixed prompt set, written from how shoppers ask and refreshed each quarter.
- The model chosen in ChatGPT's model menu, because OpenAI's model guide describes no label showing which model wrote a response ([OpenAI Help Center](https://help.openai.com/en/articles/20001354-gpt-6-and-other-models-in-chatgpt), October 2026). On a Business or Enterprise workspace, also log whether the workspace switches to deeper thinking automatically.
- Repeated runs per prompt, reported as a visibility percentage rather than a rank. SparkToro suggests 60 to 100 runs per prompt and found visibility steadier than ranking ([SparkToro](https://sparktoro.com/blog/new-research-ais-are-highly-inconsistent-when-recommending-brands-or-products-marketers-should-take-care-when-tracking-ai-visibility/), January 2026).
- Application programming interface (API) runs kept apart from app runs, because Deploi's [AI answer engine visibility record](https://deploi.ca/shopify/build-vs-buy/ai-answer-engine-visibility-geo-aeo) treats API answers as a proxy for the consumer app (October 2026).

[What Shopify's own AI channel reports show that a prompt panel cannot](https://deploi.ca/shopify/faq/search-intelligence-vs-manual-chatgpt-testing) has its own answer.

## Should your content change when OpenAI changes the model?

Your content should not change when OpenAI changes the model, because OpenAI publishes no model-specific rules for what ChatGPT surfaces. OpenAI's list of what ChatGPT considers for products, from structured metadata to the shopper's context, carries no model condition ([OpenAI Help Center](https://help.openai.com/en/articles/11128490-shopping-with-chatgpt-search), October 2026). SparkToro's data suggests that brand visibility depends less on "the model itself" than on "how many potential recommendations the AI is choosing from" ([SparkToro](https://sparktoro.com/blog/new-research-ais-are-highly-inconsistent-when-recommending-brands-or-products-marketers-should-take-care-when-tracking-ai-visibility/), January 2026).

So a visibility drop after a model change is a measurement event first. OpenAI changes ChatGPT's models several times a year. GPT-5.4 Thinking arrived in March 2026 and GPT-5.6 Sol in July, and o3 was set to leave ChatGPT on 26 August ([OpenAI's release notes](https://help.openai.com/en/articles/9624314-model-release-notes), October 2026). GPT-6 is rolling out now ([OpenAI's model guide](https://help.openai.com/en/articles/20001354-gpt-6-and-other-models-in-chatgpt), October 2026). Check those dates before you rewrite a page.

## When is version-aware tracking the wrong investment?

Version-aware tracking is the wrong investment when the number it produces cannot change a decision you own, so skip it in these four cases.

> **When not to do this**
> - **When the brand is too small for engines to name.** Deploi's [AI answer engine visibility record](https://deploi.ca/shopify/build-vs-buy/ai-answer-engine-visibility-geo-aeo) says below $2M in revenue "A measurement layer isn't worth building until there's a brand for engines to mention" (October 2026).
> - **When the panel runs only through the application programming interface (API).** Shoppers ask in the ChatGPT app, so check a sample of API answers against the app each month.
> - **When one blended score covers every model and plan.** A single number hides the plan and model split that decides what each shopper sees.
> - **When no content work follows a swing.** A log that never changes a page only records bad news, so budget the writing before the logging.

## Deploi's point of view

**Where we disagree.** Vendor dashboards report a single AI visibility score. Aggregating across models, plan tiers and personalization states into one number hides the variance that is the whole story.

**What we tell clients to do first.** rewrite the panel's prompts from real shopper questions. In our judgment, prompt sets written by the marketing team rarely match how shoppers ask, so we refresh them from real query data each quarter before anyone changes content in response to a swing.

**What this page adds.** which ChatGPT model each plan gets as of October 2026, the four documented sources of answer variance (model, web search, shopper context and run-to-run chance), and what a defensible visibility panel has to log.

## When this answer changes

- OpenAI finishes the GPT-6 rollout, or changes which model Free and Go users get.
- ChatGPT starts labelling which model wrote each response.
- OpenAI publishes model-specific rules for which products or sources ChatGPT surfaces.
- SparkToro or another named study measures how much brand visibility differs by ChatGPT model or plan.
- OpenAI changes when ChatGPT searches the web automatically.
- OpenAI changes how Business and Enterprise workspaces switch models, or what the Higher intelligence setting does.

## Sources

1. [OpenAI Help Center, GPT-6 and other models in ChatGPT](https://help.openai.com/en/articles/20001354-gpt-6-and-other-models-in-chatgpt), checked October 9, 2026
2. [OpenAI Help Center, Model Release Notes](https://help.openai.com/en/articles/9624314-model-release-notes), checked October 8, 2026
3. [OpenAI Help Center, Searching the web with ChatGPT](https://help.openai.com/en/articles/9237897-searching-the-web-with-chatgpt), checked October 8, 2026
4. [OpenAI Help Center, Shopping with ChatGPT Search](https://help.openai.com/en/articles/11128490-shopping-with-chatgpt-search), checked October 8, 2026
5. [SparkToro, NEW Research: AIs are highly inconsistent when recommending brands or products](https://sparktoro.com/blog/new-research-ais-are-highly-inconsistent-when-recommending-brands-or-products-marketers-should-take-care-when-tracking-ai-visibility/), checked October 8, 2026
6. [Deploi Build vs. Buy, Build or Buy AI Answer Engine Visibility (GEO/AEO) on Shopify?](https://deploi.ca/shopify/build-vs-buy/ai-answer-engine-visibility-geo-aeo), checked October 8, 2026, Deploi research