OpenAI cuts GPT-5.6 prices by as much as 80 percent

The cheap tier of OpenAI's newest model family just got five times cheaper, three weeks after it shipped.

OpenAI dropped GPT-5.6 Luna from $1 to 20 cents per million input tokens and from $6 to $1.20 per million output tokens, an 80 percent cut. GPT-5.6 Terra falls about 20 percent, to $2 per million input tokens and $12 per million output tokens. Sol, the most capable model in the family, keeps its price. The company credited efficiency work done while building GPT-5.6, saying it reduced the end-to-end cost of serving the model by 20 percent and improved token-generation efficiency by more than 15 percent.