OpenAI appears to be responding to the threat of cheaper Chinese open-source models with some price cuts of its own. Sam Altman announced on Thursday that OpenAI is slashing the price of GPT-5.6 Luna, the fastest and cheapest model in its GPT-5.6 lineup, by 80%. Luna now costs 20 cents per million input tokens and $1.20 per million output tokens, down from its launch pricing of $1 and $6. Terra, the mid-tier model in the family, gets a smaller but still meaningful cut, dropping 20% to $2 per million input tokens and $12 per million output tokens. Chinese labs have been undercutting Western frontier models on price by wide margins, and enterprises have noticed.