Techniques for improving scrolling performance in a web-based data grid. In one set of embodiments, when a user scrolls through a data grid rendered in a viewport of the user's web browser, client-side code executing in the web browser can detect whether a scroll event has occurred that requires a portion of the viewport to be filled/refreshed with data from a server. The client-side code can further determine whether the scroll event is a short scroll or a long scroll, and can send a request to the server that indicates the type of scroll event. If the scroll event is a short scroll, the server can determine a first amount of data to fetch based on one or more first parameters. If the scroll event is a long scroll, the server can determine a second amount of data to fetch based on one or more second parameters.