Qt, as long as you back the view with a model with O(1) lookup, can handle up to INT_MAX rows perfectly fast. I expect other cross-platform GUI toolkits work si

Qt, as long as you back the view with a model with O(1) lookup, can handle up to INT_MAX rows perfectly fast. I expect other cross-platform GUI toolkits work similarly. Most native table/list views work on an assumption of uniform row height and thus handle huge lists with no trouble. The problem browser based apps run into is rendering the entire list into the DOM and thus the browser has to lay out the whole thing in order to compute scroll bars and scroll positions. You can work around this using requestAnimationFrame, large empty padding divs, and inspecting the scroll position to create DOM elements for only things that you compute are visible. At my last job I implemented a web based table that could do 60fps scrolling on 100,000 items that were all dynamically updating using js_of_ocaml and https://github.com/janestreet/incr_dom https://github.com/janestreet/incr_dom.