Try these fixes:
Tutorial:Fighting Lag
Method 1 of 5: Reducing the Graphics Quality in Roblox
The game lagging is generally a sign of a slow game. This can be caused by having too many high-power programs using your system resources. For the most optimal experience, it is recommended that when you run Roblox, you close those other programs. To do this, take these steps:
Sometimes your ISP-supplied DNS server might be slow or not properly configured for caching, which can slow your connection a little bit. And that might be the reason that your Roblox is so laggy. To save you time troubleshooting, you’re supposed to change your DNS settings.
Here are some steps: 1) Press the Windows logo key + R to open the Run box. 2) Type %appdata% and click OK. 3) On the address bar, click Appdata. 4) Click on the Local folder. 5) Click on the Roblox folder. (Folders are listed in alphabetical order.) 6) Click on the versions folder to open it.
But with the Pro version it takes just 2 clicks (and you get full support and a 30-day money back guarantee): 1) Download and install Driver Easy. 2) Run Driver Easy and click the Scan Now button. Driver Easy will then scan your computer and detect any problem drivers.
Here’s how you can do this: 1) On your keyboard, press the Windows logo key and R at the same time to invoke the Run box. 2) Type %temp% and then press Enter on your keyboard.
Roblox is a pretty popular creation platform where you can dive into a different world and run wild. But users report experiencing inconsistent frames and lag while playing Roblox. If you happened to be one of them, don’t worry. Here’re some simple fixes to reduce the lag and speed it up!