The official Kotlin API docs on the web are not very search friendly: https://kotlinlang.org/api/core/kotlin-stdlib Ctrl+F doesn't work well. It's hard to quickly find the method you're thinking of, especially if you don't remember exactly what it's called.

What works better? IDE autocomplete. So this is autocomplete but on the web.

The primary use case for this is coding interviews. I've been in many interviews where you have to code in whatever web tool the company uses (coderpad etc.) and there's no autocomplete. But you ARE allowed to use the browser for looking things up. So instead of wading through the kotlin docs for the method you're thinking of, you can use this site instead.