Anthropic vs OpenAI: Identical Headline Prices, 4x Gap in Cache Read Costs

julsimon · x · 2026-09-26

Julien Simon notes Anthropic and OpenAI published the same two headline prices within 48 hours, yet their cache read rates differ 4x. On agentic workloads that one column decides whether routing down to a cheaper model pays — the price list is not the price. His Substack offers sourced analysis for free.

Related event: Anthropic and OpenAI Match Headline Prices, But Cache Read Costs Differ 4x(2 posts)→

Original post →

More from Models

Models channel →