OpenAI Cuts GPT-5.6 Sol API and Credit Prices by Over 20%
OpenAI has announced a price reduction of over 20% for its GPT-5.6 Sol API and Credit calls, lowering input costs to $4 and output costs to $20 per million tokens. The price cuts also apply to cached inputs and long-context tokens, and are currently rolling out to ChatGPT Work and Codex credits. This price reduction lowers the barrier to entry for developers and enterprises deploying advanced AI applications using OpenAI's most capable GPT-5.6 variant. It intensifies the price competition among frontier LLM providers, making high-performance AI integration more cost-effective. Specifically, input token prices dropped by 20% (from $5 to $4 per million) and output token prices decreased by 33% (from $30 to $20 per million). However, the usage rules and benefits for Pro, Plus, and Business subscription plans remain unchanged.
## BACKGROUND
GPT-5.6 is a family of large language models released by OpenAI in July 2026, consisting of three variants: Luna, Terra, and Sol, with Sol being the most capable. Prompt caching is a technique that stores previously processed prompt prefixes to reduce latency and API costs for subsequent requests.