Load testing SPAs with JMeter can be challenging due to their asynchronous nature. SPAs use JavaScript to render HTML pages and send requests via the XMLHttpRequest object1. However, JMeter sends HTTP requests sequentially, affecting response times. For example, if a SPA button triggers three concurrent XMLHttpRequests, JMeter processes them sequentially, leading to inaccurate response times. Solutions include custom JSR223 Sampler, Custom AJAX Request Sampler, and WebDriver Sampler, but each has limitations. Performance test engineers must understand the application’s architecture for realistic load testing in JMeter