Benchmark WebGL Application with old Monitor

I have written a small WebGL application that I would like to benchmark. My problem is that my monitor is only 60Hz, so even with the smallest instances I get max 60 FPS, but I know it could be more.

Is there a way to benchmark my program without buying a new monitor? Any changes in my Ubuntu settings (22.04) or my browser settings? Would it be possible to change something in my WebGL code? To create the animation I use

requestAnimationFrame()

I have already tried to set a higher frame rate in xandr. But with every setting I tried it just said that it is not available.

Any ideas?