Choose how you want to chat

Guest access: free, no account

Send up to 5 chat requests per UTC day and 10 per UTC month per signed browser installation. Guest conversations are not saved to history or Memory. Refreshing or closing the page clears the current guest conversation.

Try GPT-4o free

Free account: $0

A signed-in Free account can send up to 10 chat requests per UTC day and 100 per UTC month. Signed-in conversations are saved to your account, and you can manage user controlled Memory. There is no card requirement for the Free plan.

Create a free account

Pro: $25 USD per month

Pro removes Fouro's product chat-count limits and includes account-scoped AI name and custom instruction settings. Provider and service safety limits still apply. Eligible accounts can receive one 7-day introductory trial that requires a payment method. The amount due at trial signup is $0; after the trial, the subscription renews at $25 USD per month unless canceled before it ends.

Create account & review Pro trial

Already have an account? Sign in and open Billing & subscription to check trial eligibility or upgrade.

Manage or cancel Pro in Billing & subscription. Cancellation stops the next renewal; access continues through the current trial or paid period. See the Termsand support guide for more details.

When is Pro worth considering?

Start with a guest conversation to see whether GPT-4o suits how you write and think. A Free account is a good next step if you want saved conversations and occasional use. Consider Pro when the Free chat limits interrupt regular work, or when you want an AI name and instructions that apply to your signed-in chats. Pro keeps the same GPT-4o model; paying does not make answers inherently more accurate.

Try a real task from our GPT-4o prompt examples, or read what GPT-4o access in Fouro includes before choosing a plan.

What every plan uses

Fouro is configured to request GPT-4o through OpenRouter. It does not offer a model selector or intentionally switch to another model when GPT-4o is unavailable. Fouro is an independent service, not affiliated with or endorsed by OpenAI. Learn how Fouro works, read our practical GPT-4o chat guide, or start a chat.