Client-side throttling is an essential technique for managing API calls effectively and ensuring system resilience by controlling consumption logic and lowering costs. While server-side rate limiting prevents overload and maintains service quality, client-side throttling allows API consumers to proactively manage their usage according to specific business needs, preventing unexpected rate limit breaches. By implementing client-side throttling, companies can tailor API call priorities, delay non-urgent requests, and adopt algorithms like leaky bucket or sliding window to smooth traffic bursts. This approach not only prevents resource starvation and reduces client-side errors but also helps in adhering to service-level agreements and optimizing costs by avoiding unnecessary tier upgrades. Additionally, client-side throttling enhances user experience by minimizing retry rates and processing times while maintaining fair resource distribution among clients.