What are GPT models?
Quick answer
GPT models are OpenAI's family of large language models. GPT stands for "generative pre-trained transformer": a model trained on a huge amount of text that generates new text one token at a time. Each new version, and each smaller or faster variant, gets its own name and number.
Last updated
Updated · By Robert Breen
Why it matters for a small business
The name shows up in two places. In ChatGPT, you mostly don't have to choose: OpenAI's help center says that, as of October 2026, paid plans are moving to GPT-6 while the Free and Go plans default to a GPT-5.6 model, and a Thinking setting decides how long the model reasons before answering. In tools that call the OpenAI API, you do choose, from a list of named models that differ in price, speed and ability.
For a small business, the useful rule is the same one that applies to every model family: pick the smallest, cheapest model that does the job well, and move up only when it doesn't. A "mini" model costs a fraction of the flagship per token, so for sorting emails or drafting short posts it is usually the better buy. Model names change several times a year, so check OpenAI's current models page instead of trusting an old tutorial.
In a real lesson: n8n AI Agent Tutorial: Save Social Media Ideas to Google Sheets
In the AI Social Media Idea Agent lesson, you add the OpenAI Chat Model to an n8n agent and open the Model dropdown. The list is the GPT family, and the lesson picks gpt-5-mini: "Fast, cheap, and plenty for generating social media ideas."
That is the right first pick for a job like this. The agent writes three post ideas for BrightPath Marketing, a made-up agency, and saves them to a Google Sheet. Nothing about it needs the biggest model. If the ideas came back weak, you would switch the dropdown to a larger GPT model and test again, without rebuilding anything else.
Try this lesson free or read the step-by-step guide.
Common confusions
GPT models vs ChatGPT
ChatGPT is the app. GPT models are the engines inside it. The app adds memory, projects, files, search and settings on top of the model.
GPT vs "a GPT"
OpenAI also used "GPTs" for custom chatbots people built in ChatGPT. Those are being retired in favor of Projects, and they are not models.
Tips
- In automations, start with a mini model and upgrade only if the output falls short.
- Write the model name into your workflow notes so you know what to retest when it changes.
- In ChatGPT, use more thinking time for multi-step problems, not for quick drafts.
Related terms
More AI basics terms
Where you use it: free lessons
- n8n AI Agent Tutorial: Save Social Media Ideas to Google Sheets (n8n, 12 min)
- AI Email Responder: Draft Gmail Replies Automatically with n8n (n8n, 12 min)
- Prompt Writing 101: Role, Context, Task, Format (ChatGPT, 8 min)
More free tutorials
Frequently asked questions
- What does GPT stand for?
- Generative pre-trained transformer. Generative means it produces text, pre-trained means it learned from a large body of text before being tuned, and transformer is the type of neural network it uses.
- Which GPT model is in ChatGPT right now?
- As of October 2026, OpenAI's help center says GPT-6 is rolling out to paid plans and the Free and Go plans default to a GPT-5.6 model. ChatGPT shows the current model in its model menu.
- Is a newer GPT model always better?
- Usually more capable, not always better for your job. A newer flagship can cost more and run slower. For simple, repeated tasks, a smaller model is often good enough and much cheaper.