> For the complete documentation index, see [llms.txt](https://docs.rpcfast.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.rpcfast.com/rpc-fast-saas-evm/compute-units-cus/cups-rate-limit.md). # CUPS (Rate Limit) We count Compute Units per second instead of counting requests. It is our way to achieve a stable connection and keep costs low without affecting the client's UX ## How CUPS Works and Why We Use It as Rate Limit ### What Is CUPS? The way of measuring CUs we apply is called CUPS (Compute Unit Per Second). CUPS helps us to measure the rate limit and implement suitable algorithms. As we explained in the Compute Units article, each method costs a different number of CUs. It makes the CUPS limitation system more efficient than counting requests per second. There are various limitations to different pricing plans. ### Why Do We Apply Rate Limits? They allow us to ensure that clients use our services fairly and make connections stable and sustainable. We set speed limitations per second. For example, if the API returns the ‘rate limits error’ during retries, it will handle your request the next second. In general, it ultimately doesn’t affect the UX but makes the service accessible for everyone. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://docs.rpcfast.com/rpc-fast-saas-evm/compute-units-cus/cups-rate-limit.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.