Theo: Gemini is '50% more expensive than it should be' because its cache misses 27% of the time
First seen on X 32 hours ago@theo ♥ 2,4351 views
Developer and YouTuber Theo claimed Google's Gemini API prompt cache works so poorly that real costs run 50% higher than they should.
"Gemini is 50% more expensive than it should be because their cache doesn't work. 27% cache miss rate," he wrote on X on Oct. 17, adding that it was a very basic cache test simulating normal agentic work, run identically against three APIs. The post drew 2,400 likes and more than 70,000 views.
Not everyone agreed. Windsurf co-founder Varun Mohan replied, "Not what we're seeing on our workloads," saying the miss rate is very low, and asked what Theo was running. Prompt caching stores repeated input so later requests are billed at a discount; a miss means the full input is charged at list price.
“Gemini is 50% more expensive than it should be because their cache doesn't work. 27% cache miss rate. Insane.”
