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At the time this document has been written, each new ChatGPT account includes 3 months of free API usage. Following that, requests to ChatGPT API are charged on a pay-for-what-you-use basis.

Fees are currently based on the total tokens used for each request made to the API. Current fees are $0.002 per 1000 tokens used. A token can represent a single character or a whole word, depending on the language and context. As a rough guide, $5.00 worth of credit should be equal to approximately 1,875,000 words of text.

You can purchase ChatGPT API Credit from the Billing tab in your OpenAI Account Dashboard. This can be found at platform.openai.com/account/billing.

For up-to-date pricing, please see the OpenAI website.