OpenAI released a new family of AI models today called GPT-5.6, and it comes with three options instead of one. They're named Sol, Terra, and Luna — after the sun, the earth, and the moon — which is a shorthand for how powerful each one is.
Sol is the flagship. It's built for tasks that take serious thinking: complex research, writing long reports, coding projects, and multi-step problems where the AI has to plan ahead. If you've heard the phrase "deep reasoning," this is the model that does that. There's even a stronger version called Sol Ultra for the most demanding work. Most everyday users won't need this one for routine tasks.
Terra is the middle option. OpenAI describes it as balanced — roughly as capable as what ChatGPT used for last year, but at half the running cost. The most important thing for regular users: Terra is now the default model for Free and Go accounts. That means if you use ChatGPT without paying, you're getting a better AI starting today, automatically, with no action required on your part.
Luna is the smallest and fastest of the three. It replies almost instantly and costs the least to run. It's well suited for simple questions, quick lookups, and back-and-forth chat where speed matters more than depth.
If you're on a paid plan (Plus, Pro, Business, or Enterprise), you get to choose. A model picker in the chat interface lets you switch between Sol, Terra, and Luna, and you can also adjust how much thinking time the model takes. A setting called "max reasoning effort" lets Sol go deeper on hard problems — useful when you want thorough answers and don't mind waiting a few extra seconds. Want a plain-English explanation of what these three models mean in practice? Read our guide on ChatGPT Sol, Terra, and Luna explained.
OpenAI also replaced the old Advanced Voice Mode with something called GPT-Live-1. The biggest practical difference is that it works like a real phone call: you and the AI can speak at the same time, and it handles interruptions naturally instead of waiting for you to finish. There's also built-in live translation — it can interpret between languages in real time as you speak, which opens up some genuinely useful possibilities for travel or calling a family member who speaks a different language. Free accounts get the smaller GPT-Live-1 mini; paid accounts get the full version. Read more in our guide to ChatGPT voice mode.
The one thing you need to do right now: be careful about fake "upgrade" links. Every time OpenAI makes a big announcement, scammers flood social media with posts and ads that say things like "Download GPT-5.6 now — limited time!" or "Upgrade your ChatGPT to Sol here." These links lead to fake websites that either charge you money for something that's free, steal your login details, or install software you don't want on your device.
The real update happens automatically inside the official ChatGPT app and at chatgpt.com. You do not need to download anything new. You do not need to pay anyone outside of OpenAI's own website to access the new models. If a link or post is telling you otherwise, it's a scam. Our guide on how to spot fake AI apps walks you through the warning signs.
The short version: if you use ChatGPT for free, it got better today without you lifting a finger. If you pay for it, you now have more control over which model handles your requests. And the voice feature works more like a real conversation. Everything else stays the same — same app, same login, same website.