G
Jul 20, 2026GPT-5.6 Prompt Caching: The 24-Hour Cache Is Gone
GPT-5.6 added explicit prompt cache controls and quietly took the 24-hour cache away. We ran the API and measured what that swap costs.
Jul 20, 202610 min read0 reactions0 comments
Back to articles
Tag archive
#apicost
O
Jul 3, 2026OpenAI's 24h Prompt Cache: We Measured the Real Discount
OpenAI now keeps prompt caches for 24h by default on GPT-5.5. We ran the API to see when the 90% discount actually shows up, and when it doesn't.
Jul 3, 20269 min read0 reactions0 comments