OpenAI upgrading ChatGPT and Codex with two more GPT-6 models

Earlier this month, OpenAI released the first GPT-6 model with Astra. Now GPT-6 is expanding with new GPT-6 Sol and GPT-6 Luna models. Per the ChatGPT desktop app release notes, GPT-6 Sol and GPT-6 Luna will use fewer tokens to run than GPT-5.6 versions of the same class model. Note the absence of a GPT-6 Terra model. It’s expected that OpenAI is dropping the medium model in favor of just three: Terra (small), Sol (large), and Astra (extra large). The company describes its two newest models as more capable than the GPT-5.6 versions as well as more affordable than Astra (and the GPT-5.6 versions they replace). For instance, the GPT-6 versions of Sol and Luna are 50% cheaper than the GPT-5.6 versions.