In ChatGPT there's no price per image at all: you pay for the plan, and the images come out of that plan's limit. OpenAI's pricing page lists Free at $0, Go at $8 and Plus at $20 a month as of October 31, 2026, and it doesn't put a number on how many images each one gets. If you go through OpenAI's API instead, which is the developer version a programmer hooks into their own app, it's billed by tokens, little chunks of data, not by the picture. Its API pricing page lists the GPT Image 2.5 models at $30 per million image output tokens and points you to a calculator for what one image works out to.
So for one owner making a few ads a week, I'd skip the API and just use ChatGPT, because you're not paying per image and you don't need a developer to set anything up. The real cost per image is your time checking it. I read every word and digit off the picture and call the phone number on it from another phone before anything posts, because one wrong digit and you're paying to send calls to a stranger. That check and the three prompts are in my guide to turning one photo into three ads.
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