[macrolime]

What is "it". Gpt-5 auto? Gpt-5 pro? Deep research? These have wildly different hallucination rates.

[crazygringo]

I use all of the current versions of ChatGPT, Gemini, and Claude.

The hallucination rates are about the same as far as I can tell. It depends mostly on how niche the area is, not which model. They do seem to train on somewhat different sets of academic sources, so it's good to use them all.

I'm not talking about deep research or advanced thinking modes -- those are great for some tasks but don't really add anything when you're just looking for all the sources on a subject, as opposed to a research report.

[astrange]

ChatGPT thinking mode is definitely the best search engine (wrapper) I've ever used, and you should be using it to find sources.

[bathtub365]

If these rates are known it would be great for OpenAI to be open about them so customers can make an informed decision

[Maxatar]

OpenAI has published a great deal of information about hallucination rates, as have the other major LLM providers.

You can't just give one single global hallucination rate since the rates depend on the different use cases and despite the abundant amount of information available to people on how to pick the appropriate tool for a given task, it seems very few people care to take the time to actually first recognize that these LLMs are tools, and that you do need to learn how to use these tools in order to be productive with them.

[clbrmbr]

OpenAI goes into great detail on hallucination rates of GPT5 models versus o3 in the GPT5 System Card [1], section 3.7.

[1] https://cdn.openai.com/gpt-5-system-card.pdf#page12

[malfist]

"Known" implies that these rates are consistent and measurable. It seems to me, that this is highly unlikely to be the case