AI Price War Accelerates: OpenAI Cuts Sol and Luna API Prices by 50%

OpenAI has cut API prices sharply with the launch of GPT-6 Sol and GPT-6 Luna. Sol now costs $2 per million input tokens and $10 per million output tokens, down from $4 and $20 for GPT-5.6 Sol. Luna falls even further to just $0.10 input and $0.50 output, compared with $0.20 and $1.20 previously. OpenAI says improvements in caching and inference helped make these prices possible. This comes just days after Anthropic introduced Claude Opus 5.5 at $4 input and $20 output, with Anthropic claiming around 40% lower cost on typical workloads than Opus 5. Importantly, Anthropic’s 40% figure is not a 40% cut in token prices. Its listed input and output prices fell 20%, while lower token usage and cheaper cache reads account for the larger claimed workload saving.

The price competition is now becoming clearer. Grok 4.7 costs $2 input / $6 output, while Google’s Gemini 3.1 Pro costs $2 / $12 for prompts up to 200,000 tokens. That puts GPT-6 Sol in the middle of the group on headline token price, while Luna targets a very different low-cost segment. For businesses, the important number is increasingly not just the price of one million tokens, but the cost of completing a useful task. A more expensive model can still be economical if it needs fewer tokens, fewer retries or less human correction. AI Wallet should therefore track both token prices and real workload efficiency as this price competition develops.