OpenRouter explains open-weight versus closed-weight models with usage and price data
AIOpenRouter defines open-weight models as models whose trained weights are published, and says they are available from many providers rather than only the model's maker. Its data shows open-weight models handled 71.7% of top-50 model tokens in the week of September 28, 2026, and cost about a quarter as much per token.
AIWhy it matters.
The post separates usage, price, and quality data from its own measurements, so readers can judge the open-weight trade-off against their own workload.
Source details
OpenRouter Blog · openrouter.aiPublished · added here
Original title: Open-Weight vs Closed-Weight Models: What's the Difference?