Hint: It's not 15%. And there are many reasons, such as not having to keep up-to-date billing details in 70 providers, and not wasting money because most providers want you to prepay a balance that gets stuck in there if you switch to another provider.

It also has way better uptime than the underlying platforms, even for proprietary models like Claude. When Claude APIs are having issues, OpenRouter Claude still keeps working because they can route to AWS Bedrock instead of Anthropic etc. This effect is even bigger with open-weight models because they typically have 5-10 providers.