Clear your cookies and cache regularly! This is the most common fix for any issues of slowness on your computer. See the steps to clear your internet cache here. After you’ve done this, close all browser windows (not just a few tabs, the whole browser!) and re-open chess.com.

Pause any downloads or uploads on your computer. If you are downloading a large file, this takes up bandwidth and can cause lag.

Close any other browser tabs that are streaming content. Streaming video or music uses bandwidth just like downloading a large file does. If you’re having connection problems, try pausing your streaming while you play chess.

Disable browser extensions. Sometimes these use a lot of memory, or alter the JavaScript or other files used by chess.com, or alter your connection in some way. It's best to disable them while playing!

Check Task Manager to see if any programs are using up a lot of memory, and close them while you play chess.

If you have a high number of browser tabs open, try closing all tabs except chess.com. Even if you aren’t streaming or downloading, each tab takes up some of your computer’s memory.

Make sure your browser is updated to the most current version. If you are using Internet Explorer, try using Chrome or Firefox instead. Internet Explorer is no longer updated by Microsoft and many modern websites do not function correctly on Internet Explorer

Try using a Wired Connection. Sometimes it is an unstable WiFi connection causing the issue. Try being closer to your router, or even using a wired connection.