Open-weight models are rapidly reshaping the market, according to a new report by OpenRouter and a16z, based on the analysis of over 100 trillion tokens of real LLM usage.
OpenRouter is a "unified API" for hundreds of AI models, allowing developers to access LLMs from different providers without setting up separate integrations.
While at the end of 2024, Chinese open-source models accounted for an average of just 1.2% of weekly tokens, by 2025 their share had risen to nearly 30%, thanks to releases from DeepSeek, Qwen, and other products.
Moreover, this growth hasn't been limited to a "hype wave": the share of open models has remained stable, indicating real-world adoption.
According to OpenRouter, open-weight models have become a true alternative to closed AI: they are cheaper, more flexible, customizable, and especially attractive for tasks where high stability isn't required, and openness is important.