GPT-6 Luna Flex
Use it free in free-pi
slower, half price · ~1x usage
npx free-pi-cli
/model gpt-6-luna-flexAbout GPT-6 Luna Flex
GPT-6 Luna Flex is the same model as GPT-6 Luna, OpenAI's fast, smaller GPT-6 model, served on OpenAI's flex tier, which is slower and cheaper. The model is unchanged: the same context window of about 1,050,000 tokens, the same text, image, and file input, and the same reasoning, tool calling, and structured output support. The agent can still read and edit files, run commands, and use free-pi's web search and documentation tools.
The difference is speed and allowance. Responses are slower on the flex tier, and the model uses less of your daily allowance. In free-pi it counts as about 1x usage, compared with about 0.5x for the regular version, so your allowance lasts about twice as long. At 1x it uses the same amount of allowance as the default model. It is free with no API key and no card.
When to pick it
For GPT-6 Luna on work that is not urgent, where you want your allowance to last longer than on the regular tier, pick GPT-6 Luna Flex. It is the way to get an OpenAI model with image and file input at the same allowance rate as the default.
For faster replies, pick the regular GPT-6 Luna. For text-only work at the same rate, pick the default DeepSeek V4 Flash.