GPT-4o guides
Get more from GPT-4o
Start with the question you have: where to use GPT-4o, what Fouro includes, or how to get a more useful answer.
Last updated September 29, 2026
Where to chat with GPT-4o
See how GPT-4o access works in Fouro, what you can try without an account, and how Free and Pro differ. Fouro is an independent service that requests GPT-4o through OpenRouter.
Choosing a ChatGPT GPT-4o alternative
Compare model access with the surrounding product experience. Learn what Fouro provides and what it does not reproduce from ChatGPT, including account history and tool availability.
Practical GPT-4o prompt examples
Try concrete prompts for drafting, learning, making a plan, and reviewing code. Each example explains the context to add and a useful follow-up question.
Getting a more useful answer
Improve a conversation by giving context, choosing an output format, and reviewing the result. Learn how saved conversations, Memory, and Pro instructions support repeat tasks.
Try it on something real
Guest access needs no account and includes up to 5 chats per UTC day and 10 per UTC month per signed browser. Guest chats are not saved to history or Memory. For saved conversations or regular use, compare Free and Pro.