OpenAI cuts GPT-5.6 Luna price 80% to $0.20 per million input tokens

OpenAI has cut the price of its GPT-5.6 Luna model by 80% to $0.20 per million input tokens and $1.20 per million output tokens, making it cheaper than Anthropic's Claude Haiku 4.5 for input. The price reduction is partly attributed to GPT-5.6 Sol autonomously optimizing serving kernels, cutting end-to-end serving costs by 20%, according to Simon Willison.

Simon Willison https://simonwillison.net/2026/Jul/30/luna-price-drop/ atom-everything OpenAI cuts GPT-5.6 Luna price 80% to $0.20 per million input tokens Which summary reads better? Pick one — models revealed after.Both summaries are AI-generated. GPT-5.6 Luna dropped 80% to $0.20 per million input tokens and $1.20 per million output tokens, making it cheap enough to replace budget models in production agent workloads. The notable operational signal is that OpenAI attributes part of this to GPT-5.6 Sol autonomously optimizing serving kernels and cutting end-to-end serving costs by 20%, so model-assisted inference optimization is now directly translating into lower API prices. GPT-5.6 Luna now costs $0.20 per million input tokens and $1.20 per million output tokens, an 80% drop that makes it 1/5th the price of Anthropic's Claude Haiku 4.5 for input, enabling cost-effective deployment of language models for production workloads, including agent-based applications.