AI Gateway Production Index — September 2026
Every month, AI Gateway routes tens of trillions of tokens between production applications and AI labs. That traffic gives us a view of what AI usage actually looks like in today's enterprise, and we publish it here monthly. See the Production Index reports from June, July, and August.
September 2026 summary
The September index reports on AI Gateway data collected through August 2026.
Open-weight models ran the majority of gateway tokens for the first time, up from 7% in December to 56% in August.
The average token costs less than half what it did five months ago. Price per token fell 23.2% in August, the third straight monthly drop, and the median team paid 7.6% less.
Fable 5, Anthropic's most capable model, lost two-thirds of its share of gateway spend in one month. Opus 5, at half the price, tripled its share. Anthropic kept 64% of all spend.
Gemini 3 Flash has lost 95% of its share of gateway tokens since May, and more than three-quarters of the volume it lost went to models from other labs.
Special report: OpenAI launches Astra on September 3
GPT-6 Astra took a third of OpenAI's spend within two days of launch and twice Fable 5.1's share of gateway spend. Introduced two days apart at the same price, Astra took 7.7% of all gateway spend in its first twelve days, while Fable 5.1 took 3.7%.
Open-weight models take a majority of token volume for the first time
In August, open-weight models ran 56% of all tokens on AI Gateway, marking the first month they took the majority of volume.
In December 2025, they processed fewer than one in ten tokens, and only eight months later, they ran more token volume than all closed-weight models combined.
Though the frontier kept the majority of spend, open-weight dollar share is accelerating. As open-weight models become more capable, customers are moving more production workloads over to them.
Growth in open-weight model adoption helped push the average price per token across the gateway down 23.2% in August, its third consecutive monthly drop and the steepest since April. Among teams running more than ten million tokens in both months, the median team paid 7.6% less per token, more than double July's 2.9% decline.