ChatGPT got GPT-6, but you can't use it in Chat — confused?

(Image credit: Shutterstock / Krakenimages.com) ChatGPT just got GPT-6, except there’s a catch: you can’t actually use it in Chat.If that sentence makes absolutely no sense to you, I don’t blame you. Until now, you could use ChatGPT quite happily without giving much thought to the distinction between Chat and Work functionalities. I certainly did. It was just that little slider at the top of the screen I never bothered with.I suspect most of you are the same. Chat was where I talked to ChatGPT, while Work was something sitting alongside it that I could largely ignore because the Chat setting let me do almost everything I wanted.GPT-6 changes that. OpenAI’s newest model has arrived in ChatGPT, but instead of appearing in the familiar model picker on the right hand side of the prompt bar, GPT-6 Astra, Sol and Luna are available in Work and Codex only. So, naturally, the first thing I did was go looking for them.And somewhere between opening Work, figuring out what OpenAI actually expects me to do there, and finally getting my hands on GPT-6, I realized this launch is about more than a new model. OpenAI has just made the difference between chatting with ChatGPT and asking it to work for you in a way it never really did before.When to Chat and when to WorkThe easiest way I’ve found to understand the difference is to think about how much of the job I want ChatGPT to take responsibility for. In a normal Chat conversation, I’m usually working alongside the AI. I ask something, look at the response, add more information and gradually steer it towards what I need.Work feels different because I’m handing over more of the process. I can give ChatGPT a larger task involving multiple steps and let it work out how to approach it, which might mean researching information, looking through files or using websites rather than waiting for me to tell it what to do at every stage.Sign up for breaking news, reviews, opinion, top tech deals, and more.If I’ve got a bigger job involving several files or lots of moving parts, I’ll often start there and let ChatGPT work out what it needs before I get involved again. Chat feels collaborative; Work feels much more like delegation.I wouldn’t nominate OpenAI for any interface design awards because one of the reasons that the distinction between Work and Chat is so confusing is that they both use exactly the same interface, with a prompt bar at the bottom of the screen.In fact, you can choose Work mode and then just start chatting to the AI as you normally would, although I've tried this, and it's not a particularly good experience. Responses can take considerably longer than they do in Chat, because Work is designed around longer, multi-step jobs rather than firing back quick conversational answers. If I just want to ask ChatGPT something, Chat remains the obvious place to do it.And once you understand that distinction, putting GPT-6 Astra, Sol and Luna in Work rather than Chat starts to look considerably less strange. (Image credit: Apple / OpenAI)So what exactly is GPT-6?OpenAI calls GPT-6 Astra “the most intelligent and aligned model in the world”. Think of it as the heavyweight of the family: OpenAI's most capable model, built for the really difficult jobs where you want maximum intelligence rather than maximum speed. OpenAI particularly emphasizes Astra's ability to operate software, browse, conduct research and complete multistep professional workflows.And because not every job requires the power of a burning sun to complete, OpenAI has also released two smaller versions called GPT-6 Sol and GPT-6 Luna. These models are more lightweight and less expensive to use. They’re trained using similar methods to GPT-6 Astra, but OpenAI say they “build on the advances behind GPT-6 Astra” and bring much of its strengths into faster and more affordable models.There is one wrinkle here. GPT-6 Astra has actually been around since earlier this month, and GPT-6 Pro, which is powered by Astra, is available in regular Chat on some higher-tier plans. I'm a ChatGPT Plus subscriber, however, which means my access to Astra — and now the new GPT-6 Sol and Luna models — is through Work and Codex.If I switch to the Work tab in my Plus account then in the model picker I get access to GPT-6 Luna High, GPT-6 Sol Light, GPT-6 Sol Medium, GPT-6 Astra Light and GPT-6 Astra Medium.Until now, I could happily spend all my time in Chat, using GPT-5.6 Sol, and largely ignore Work. GPT-6 changes that. OpenAI isn't just giving us smarter models; it's starting to separate the AI we talk to from the AI we give jobs to. If its most powerful new models are going to live on the Work side of that divide, then that little switch I've spent months ignoring suddenly matters a lot more. Follow TechRadar on Google News and add us as a preferred source to get our expert news, reviews, and opinion in your feeds. Graham is the Senior Editor for AI at TechRadar. With over 25 years of experience in both online and print journalism, Graham has worked for various market-leading tech brands including Computeractive, PC Pro, iMore, MacFormat, Mac|Life, Maximum PC, and more. He specializes in reporting on everything to do with AI and has appeared on BBC TV shows like BBC One Breakfast and on Radio 4 commenting on the latest trends in tech. Graham has an honors degree in Computer Science and spends his spare time podcasting and blogging.