OpenAI retakes OpenRouter weekly spend lead after 2.5 years

In the week of September 7 through 13, 2026, OpenRouter users spent more on OpenAI models than on Anthropic's for the first time in more than two and a half years. "This hasn't happened for more than 2.5 years," OpenRouter wrote on X, pointing to the week of February 26, 2024 as the previous crossing.

The breakdown is where the story lives. GPT-6 Astra accounted for 19% of the combined dollar spend between the two labs. Claude Opus 5 came in at 16%. GPT-5.6 Sol and Luna each held 10%, Claude Sonnet 5 took 7%, and Claude Fable 5.1 took 6%.

Astra lists at $10 per million input tokens and $50 per million output tokens. Luna, by contrast, runs $0.20 per million input and $1.20 per million output after OpenAI cut its API rates by 80% on July 30. Luna "processed the most tokens by a wide margin" even as Astra pulled the dollar lead, per Runtimewire's writeup of the OpenRouter numbers.

The Wall Street Journal frames this as part of a wider price war. Anthropic had held 75% to 80% of combined OpenRouter spend across most of 2024 and 2025, then slipped into the high 50s by mid-August 2026 before OpenAI edged past. Our tracker has logged 405 OpenAI stories and 337 Anthropic ones in the last ninety days.

One weekly snapshot is one weekly snapshot. Neither OpenRouter nor the outlets citing its data break out how much of Astra's 19% came from net-new usage versus routing changes toward the newer model.